cpp conversion: move source files in apps/ iso19111/ conversions/ projections/ transformations/ tests/ subdirectories

12 files changed, 43116 insertions, 0 deletions

diff --git a/src/iso19111/c_api.cpp b/src/iso19111/c_api.cpp
new file mode 100644
index 00000000..d0b5d720
--- /dev/null
+++ b/src/iso19111/c_api.cpp
@@ -0,0 +1,6540 @@
+/******************************************************************************
+ *
+ * Project:  PROJ
+ * Purpose:  C API wraper of C++ API
+ * Author:   Even Rouault <even dot rouault at spatialys dot com>
+ *
+ ******************************************************************************
+ * Copyright (c) 2018, Even Rouault <even dot rouault at spatialys dot com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ ****************************************************************************/
+
+#ifndef FROM_PROJ_CPP
+#define FROM_PROJ_CPP
+#endif
+
+#include <cassert>
+#include <cstdarg>
+#include <cstring>
+#include <map>
+#include <utility>
+#include <vector>
+
+#include "proj/common.hpp"
+#include "proj/coordinateoperation.hpp"
+#include "proj/coordinatesystem.hpp"
+#include "proj/crs.hpp"
+#include "proj/datum.hpp"
+#include "proj/io.hpp"
+#include "proj/metadata.hpp"
+#include "proj/util.hpp"
+
+#include "proj/internal/internal.hpp"
+
+// PROJ include order is sensitive
+// clang-format off
+#include "proj_internal.h"
+#include "proj.h"
+#include "proj_experimental.h"
+#include "projects.h"
+// clang-format on
+#include "proj_constants.h"
+
+using namespace NS_PROJ::common;
+using namespace NS_PROJ::crs;
+using namespace NS_PROJ::cs;
+using namespace NS_PROJ::datum;
+using namespace NS_PROJ::io;
+using namespace NS_PROJ::internal;
+using namespace NS_PROJ::metadata;
+using namespace NS_PROJ::operation;
+using namespace NS_PROJ::util;
+using namespace NS_PROJ;
+
+// ---------------------------------------------------------------------------
+
+static void PROJ_NO_INLINE proj_log_error(PJ_CONTEXT *ctx, const char *function,
+                                          const char *text) {
+    std::string msg(function);
+    msg += ": ";
+    msg += text;
+    ctx->logger(ctx->app_data, PJ_LOG_ERROR, msg.c_str());
+}
+
+// ---------------------------------------------------------------------------
+
+static void PROJ_NO_INLINE proj_log_debug(PJ_CONTEXT *ctx, const char *function,
+                                          const char *text) {
+    std::string msg(function);
+    msg += ": ";
+    msg += text;
+    ctx->logger(ctx->app_data, PJ_LOG_DEBUG, msg.c_str());
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Opaque object representing a Ellipsoid, Datum, CRS or Coordinate
+ * Operation. Should be used by at most one thread at a time. */
+struct PJ_OBJ {
+    //! @cond Doxygen_Suppress
+    IdentifiedObjectNNPtr obj;
+
+    // cached results
+    mutable std::string lastWKT{};
+    mutable std::string lastPROJString{};
+    mutable bool gridsNeededAsked = false;
+    mutable std::vector<GridDescription> gridsNeeded{};
+
+    explicit PJ_OBJ(const IdentifiedObjectNNPtr &objIn) : obj(objIn) {}
+    static PJ_OBJ *create(const IdentifiedObjectNNPtr &objIn);
+
+    PJ_OBJ(const PJ_OBJ &) = delete;
+    PJ_OBJ &operator=(const PJ_OBJ &) = delete;
+    //! @endcond
+};
+
+//! @cond Doxygen_Suppress
+PJ_OBJ *PJ_OBJ::create(const IdentifiedObjectNNPtr &objIn) {
+    return new PJ_OBJ(objIn);
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Opaque object representing a set of operation results. */
+struct PJ_OBJ_LIST {
+    //! @cond Doxygen_Suppress
+    std::vector<IdentifiedObjectNNPtr> objects;
+
+    explicit PJ_OBJ_LIST(std::vector<IdentifiedObjectNNPtr> &&objectsIn)
+        : objects(std::move(objectsIn)) {}
+
+    PJ_OBJ_LIST(const PJ_OBJ_LIST &) = delete;
+    PJ_OBJ_LIST &operator=(const PJ_OBJ_LIST &) = delete;
+    //! @endcond
+};
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+/** Auxiliary structure to PJ_CONTEXT storing C++ context stuff. */
+struct projCppContext {
+    DatabaseContextNNPtr databaseContext;
+    std::string lastUOMName_{};
+
+    explicit projCppContext(PJ_CONTEXT *ctx, const char *dbPath = nullptr,
+                            const char *const *auxDbPaths = nullptr)
+        : databaseContext(DatabaseContext::create(
+              dbPath ? dbPath : std::string(), toVector(auxDbPaths))) {
+        databaseContext->attachPJContext(ctx);
+    }
+
+    static std::vector<std::string> toVector(const char *const *auxDbPaths) {
+        std::vector<std::string> res;
+        for (auto iter = auxDbPaths; iter && *iter; ++iter) {
+            res.emplace_back(std::string(*iter));
+        }
+        return res;
+    }
+};
+
+// ---------------------------------------------------------------------------
+
+void proj_context_delete_cpp_context(struct projCppContext *cppContext) {
+    delete cppContext;
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+#define SANITIZE_CTX(ctx)                                                      \
+    do {                                                                       \
+        if (ctx == nullptr) {                                                  \
+            ctx = pj_get_default_ctx();                                        \
+        }                                                                      \
+    } while (0)
+
+// ---------------------------------------------------------------------------
+
+static PROJ_NO_INLINE const DatabaseContextNNPtr &
+getDBcontext(PJ_CONTEXT *ctx) {
+    if (ctx->cpp_context == nullptr) {
+        ctx->cpp_context = new projCppContext(ctx);
+    }
+    return ctx->cpp_context->databaseContext;
+}
+
+// ---------------------------------------------------------------------------
+
+static PROJ_NO_INLINE DatabaseContextPtr
+getDBcontextNoException(PJ_CONTEXT *ctx, const char *function) {
+    try {
+        return getDBcontext(ctx).as_nullable();
+    } catch (const std::exception &e) {
+        proj_log_debug(ctx, function, e.what());
+        return nullptr;
+    }
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Explicitly point to the main PROJ CRS and coordinate operation
+ * definition database ("proj.db"), and potentially auxiliary databases with
+ * same structure.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param dbPath Path to main database, or NULL for default.
+ * @param auxDbPaths NULL-terminated list of auxiliary database filenames, or
+ * NULL.
+ * @param options should be set to NULL for now
+ * @return TRUE in case of success
+ */
+int proj_context_set_database_path(PJ_CONTEXT *ctx, const char *dbPath,
+                                   const char *const *auxDbPaths,
+                                   const char *const *options) {
+    SANITIZE_CTX(ctx);
+    (void)options;
+    delete ctx->cpp_context;
+    ctx->cpp_context = nullptr;
+    try {
+        ctx->cpp_context = new projCppContext(ctx, dbPath, auxDbPaths);
+        return true;
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+        return false;
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns the path to the database.
+ *
+ * The returned pointer remains valid while ctx is valid, and until
+ * proj_context_set_database_path() is called.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @return path, or nullptr
+ */
+const char *proj_context_get_database_path(PJ_CONTEXT *ctx) {
+    SANITIZE_CTX(ctx);
+    try {
+        return getDBcontext(ctx)->getPath().c_str();
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+        return nullptr;
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return a metadata from the database.
+ *
+ * The returned pointer remains valid while ctx is valid, and until
+ * proj_context_get_database_metadata() is called.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param key Metadata key. Must not be NULL
+ * @return value, or nullptr
+ */
+const char *proj_context_get_database_metadata(PJ_CONTEXT *ctx,
+                                               const char *key) {
+    SANITIZE_CTX(ctx);
+    try {
+        return getDBcontext(ctx)->getMetadata(key);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+        return nullptr;
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Guess the "dialect" of the WKT string.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param wkt String (must not be NULL)
+ */
+PJ_GUESSED_WKT_DIALECT proj_context_guess_wkt_dialect(PJ_CONTEXT *ctx,
+                                                      const char *wkt) {
+    (void)ctx;
+    assert(wkt);
+    switch (WKTParser().guessDialect(wkt)) {
+    case WKTParser::WKTGuessedDialect::WKT2_2018:
+        return PJ_GUESSED_WKT2_2018;
+    case WKTParser::WKTGuessedDialect::WKT2_2015:
+        return PJ_GUESSED_WKT2_2015;
+    case WKTParser::WKTGuessedDialect::WKT1_GDAL:
+        return PJ_GUESSED_WKT1_GDAL;
+    case WKTParser::WKTGuessedDialect::WKT1_ESRI:
+        return PJ_GUESSED_WKT1_ESRI;
+    case WKTParser::WKTGuessedDialect::NOT_WKT:
+        break;
+    }
+    return PJ_GUESSED_NOT_WKT;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static const char *getOptionValue(const char *option,
+                                  const char *keyWithEqual) noexcept {
+    if (ci_starts_with(option, keyWithEqual)) {
+        return option + strlen(keyWithEqual);
+    }
+    return nullptr;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief "Clone" an object.
+ *
+ * Technically this just increases the reference counter on the object, since
+ * PJ_OBJ objects are immutable.
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param obj Object to clone. Must not be NULL.
+ * @return Object that must be unreferenced with proj_obj_destroy(), or NULL in
+ * case of error.
+ */
+PJ_OBJ *proj_obj_clone(PJ_CONTEXT *ctx, const PJ_OBJ *obj) {
+    SANITIZE_CTX(ctx);
+    try {
+        return PJ_OBJ::create(obj->obj);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate an object from a WKT string, PROJ string or object code
+ * (like "EPSG:4326", "urn:ogc:def:crs:EPSG::4326",
+ * "urn:ogc:def:coordinateOperation:EPSG::1671").
+ *
+ * This function calls osgeo::proj::io::createFromUserInput()
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param text String (must not be NULL)
+ * @param options null-terminated list of options, or NULL. Currently
+ * supported options are:
+ * <ul>
+ * <li>USE_PROJ4_INIT_RULES=YES/NO. Defaults to NO. When set to YES,
+ * init=epsg:XXXX syntax will be allowed and will be interpreted according to
+ * PROJ.4 and PROJ.5 rules, that is geodeticCRS will have longitude, latitude
+ * order and will expect/output coordinates in radians. ProjectedCRS will have
+ * easting, northing axis order (except the ones with Transverse Mercator South
+ * Orientated projection). In that mode, the epsg:XXXX syntax will be also
+ * interprated the same way.</li>
+ * </ul>
+ * @return Object that must be unreferenced with proj_obj_destroy(), or NULL in
+ * case of error.
+ */
+PJ_OBJ *proj_obj_create_from_user_input(PJ_CONTEXT *ctx, const char *text,
+                                        const char *const *options) {
+    SANITIZE_CTX(ctx);
+    assert(text);
+    (void)options;
+    auto dbContext = getDBcontextNoException(ctx, __FUNCTION__);
+    try {
+        bool usePROJ4InitRules = false;
+        for (auto iter = options; iter && iter[0]; ++iter) {
+            const char *value;
+            if ((value = getOptionValue(*iter, "USE_PROJ4_INIT_RULES="))) {
+                usePROJ4InitRules = ci_equal(value, "YES");
+            } else {
+                std::string msg("Unknown option :");
+                msg += *iter;
+                proj_log_error(ctx, __FUNCTION__, msg.c_str());
+                return nullptr;
+            }
+        }
+        auto identifiedObject = nn_dynamic_pointer_cast<IdentifiedObject>(
+            createFromUserInput(text, dbContext, usePROJ4InitRules));
+        if (identifiedObject) {
+            return PJ_OBJ::create(NN_NO_CHECK(identifiedObject));
+        }
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+template <class T> static PROJ_STRING_LIST to_string_list(T &&set) {
+    auto ret = new char *[set.size() + 1];
+    size_t i = 0;
+    for (const auto &str : set) {
+        try {
+            ret[i] = new char[str.size() + 1];
+        } catch (const std::exception &) {
+            while (--i > 0) {
+                delete[] ret[i];
+            }
+            delete[] ret;
+            throw;
+        }
+        std::memcpy(ret[i], str.c_str(), str.size() + 1);
+        i++;
+    }
+    ret[i] = nullptr;
+    return ret;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate an object from a WKT string.
+ *
+ * This function calls osgeo::proj::io::WKTParser::createFromWKT()
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param wkt WKT string (must not be NULL)
+ * @param options null-terminated list of options, or NULL. Currently
+ * supported options are:
+ * <ul>
+ * <li>STRICT=YES/NO. Defaults to NO. When set to YES, strict validation will
+ * be enabled.</li>
+ * </ul>
+ * @param out_warnings Pointer to a PROJ_STRING_LIST object, or NULL.
+ * If provided, *out_warnings will contain a list of warnings, typically for
+ * non recognized projection method or parameters. It must be freed with
+ * proj_string_list_destroy().
+ * @param out_grammar_errors Pointer to a PROJ_STRING_LIST object, or NULL.
+ * If provided, *out_grammar_errors will contain a list of errors regarding the
+ * WKT grammaer. It must be freed with proj_string_list_destroy().
+ * @return Object that must be unreferenced with proj_obj_destroy(), or NULL in
+ * case of error.
+ */
+PJ_OBJ *proj_obj_create_from_wkt(PJ_CONTEXT *ctx, const char *wkt,
+                                 const char *const *options,
+                                 PROJ_STRING_LIST *out_warnings,
+                                 PROJ_STRING_LIST *out_grammar_errors) {
+    SANITIZE_CTX(ctx);
+    assert(wkt);
+
+    if (out_warnings) {
+        *out_warnings = nullptr;
+    }
+    if (out_grammar_errors) {
+        *out_grammar_errors = nullptr;
+    }
+
+    try {
+        WKTParser parser;
+        auto dbContext = getDBcontextNoException(ctx, __FUNCTION__);
+        if (dbContext) {
+            parser.attachDatabaseContext(NN_NO_CHECK(dbContext));
+        }
+        for (auto iter = options; iter && iter[0]; ++iter) {
+            const char *value;
+            if ((value = getOptionValue(*iter, "STRICT="))) {
+                parser.setStrict(ci_equal(value, "YES"));
+            } else {
+                std::string msg("Unknown option :");
+                msg += *iter;
+                proj_log_error(ctx, __FUNCTION__, msg.c_str());
+                return nullptr;
+            }
+        }
+        auto obj = nn_dynamic_pointer_cast<IdentifiedObject>(
+            parser.createFromWKT(wkt));
+
+        if (out_grammar_errors) {
+            auto warnings = parser.warningList();
+            if (!warnings.empty()) {
+                *out_grammar_errors = to_string_list(warnings);
+            }
+        }
+
+        if (obj && out_warnings) {
+            auto derivedCRS = dynamic_cast<const crs::DerivedCRS *>(obj.get());
+            if (derivedCRS) {
+                auto warnings =
+                    derivedCRS->derivingConversionRef()->validateParameters();
+                if (!warnings.empty()) {
+                    *out_warnings = to_string_list(warnings);
+                }
+            } else {
+                auto singleOp =
+                    dynamic_cast<const operation::SingleOperation *>(obj.get());
+                if (singleOp) {
+                    auto warnings = singleOp->validateParameters();
+                    if (!warnings.empty()) {
+                        *out_warnings = to_string_list(warnings);
+                    }
+                }
+            }
+        }
+
+        if (obj) {
+            return PJ_OBJ::create(NN_NO_CHECK(obj));
+        }
+    } catch (const std::exception &e) {
+        if (out_grammar_errors) {
+            std::list<std::string> exc{e.what()};
+            try {
+                *out_grammar_errors = to_string_list(exc);
+            } catch (const std::exception &) {
+                proj_log_error(ctx, __FUNCTION__, e.what());
+            }
+        } else {
+            proj_log_error(ctx, __FUNCTION__, e.what());
+        }
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate an object from a PROJ string.
+ *
+ * This function calls osgeo::proj::io::PROJStringParser::createFromPROJString()
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param proj_string PROJ string (must not be NULL)
+ * @param options should be set to NULL for now
+ * @return Object that must be unreferenced with proj_obj_destroy(), or NULL in
+ * case of error.
+ */
+PJ_OBJ *proj_obj_create_from_proj_string(PJ_CONTEXT *ctx,
+                                         const char *proj_string,
+                                         const char *const *options) {
+    SANITIZE_CTX(ctx);
+    (void)options;
+    assert(proj_string);
+    try {
+        PROJStringParser parser;
+        auto dbContext = getDBcontextNoException(ctx, __FUNCTION__);
+        if (dbContext) {
+            parser.attachDatabaseContext(NN_NO_CHECK(dbContext));
+        }
+        auto identifiedObject = nn_dynamic_pointer_cast<IdentifiedObject>(
+            parser.createFromPROJString(proj_string));
+        if (identifiedObject) {
+            return PJ_OBJ::create(NN_NO_CHECK(identifiedObject));
+        }
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate an object from a database lookup.
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx Context, or NULL for default context.
+ * @param auth_name Authority name (must not be NULL)
+ * @param code Object code (must not be NULL)
+ * @param category Object category
+ * @param usePROJAlternativeGridNames Whether PROJ alternative grid names
+ * should be substituted to the official grid names. Only used on
+ * transformations
+ * @param options should be set to NULL for now
+ * @return Object that must be unreferenced with proj_obj_destroy(), or NULL in
+ * case of error.
+ */
+PJ_OBJ *proj_obj_create_from_database(PJ_CONTEXT *ctx, const char *auth_name,
+                                      const char *code,
+                                      PJ_OBJ_CATEGORY category,
+                                      int usePROJAlternativeGridNames,
+                                      const char *const *options) {
+    assert(auth_name);
+    assert(code);
+    (void)options;
+    SANITIZE_CTX(ctx);
+    try {
+        const std::string codeStr(code);
+        auto factory = AuthorityFactory::create(getDBcontext(ctx), auth_name);
+        IdentifiedObjectPtr obj;
+        switch (category) {
+        case PJ_OBJ_CATEGORY_ELLIPSOID:
+            obj = factory->createEllipsoid(codeStr).as_nullable();
+            break;
+        case PJ_OBJ_CATEGORY_PRIME_MERIDIAN:
+            obj = factory->createPrimeMeridian(codeStr).as_nullable();
+            break;
+        case PJ_OBJ_CATEGORY_DATUM:
+            obj = factory->createDatum(codeStr).as_nullable();
+            break;
+        case PJ_OBJ_CATEGORY_CRS:
+            obj =
+                factory->createCoordinateReferenceSystem(codeStr).as_nullable();
+            break;
+        case PJ_OBJ_CATEGORY_COORDINATE_OPERATION:
+            obj = factory
+                      ->createCoordinateOperation(
+                          codeStr, usePROJAlternativeGridNames != 0)
+                      .as_nullable();
+            break;
+        }
+        return PJ_OBJ::create(NN_NO_CHECK(obj));
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static const char *get_unit_category(UnitOfMeasure::Type type) {
+    const char *ret = nullptr;
+    switch (type) {
+    case UnitOfMeasure::Type::UNKNOWN:
+        ret = "unknown";
+        break;
+    case UnitOfMeasure::Type::NONE:
+        ret = "none";
+        break;
+    case UnitOfMeasure::Type::ANGULAR:
+        ret = "angular";
+        break;
+    case UnitOfMeasure::Type::LINEAR:
+        ret = "linear";
+        break;
+    case UnitOfMeasure::Type::SCALE:
+        ret = "scale";
+        break;
+    case UnitOfMeasure::Type::TIME:
+        ret = "time";
+        break;
+    case UnitOfMeasure::Type::PARAMETRIC:
+        ret = "parametric";
+        break;
+    }
+    return ret;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Get information for a unit of measure from a database lookup.
+ *
+ * @param ctx Context, or NULL for default context.
+ * @param auth_name Authority name (must not be NULL)
+ * @param code Unit of measure code (must not be NULL)
+ * @param out_name Pointer to a string value to store the parameter name. or
+ * NULL. This value remains valid until the next call to
+ * proj_uom_get_info_from_database() or the context destruction.
+ * @param out_conv_factor Pointer to a value to store the conversion
+ * factor of the prime meridian longitude unit to radian. or NULL
+ * @param out_category Pointer to a string value to store the parameter name. or
+ * NULL. This value might be "unknown", "none", "linear", "angular", "scale",
+ * "time" or "parametric";
+ * @return TRUE in case of success
+ */
+int proj_uom_get_info_from_database(PJ_CONTEXT *ctx, const char *auth_name,
+                                    const char *code, const char **out_name,
+                                    double *out_conv_factor,
+                                    const char **out_category) {
+    assert(auth_name);
+    assert(code);
+    SANITIZE_CTX(ctx);
+    try {
+        auto factory = AuthorityFactory::create(getDBcontext(ctx), auth_name);
+        auto obj = factory->createUnitOfMeasure(code);
+        if (out_name) {
+            ctx->cpp_context->lastUOMName_ = obj->name();
+            *out_name = ctx->cpp_context->lastUOMName_.c_str();
+        }
+        if (out_conv_factor) {
+            *out_conv_factor = obj->conversionToSI();
+        }
+        if (out_category) {
+            *out_category = get_unit_category(obj->type());
+        }
+        return true;
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return false;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return GeodeticCRS that use the specified datum.
+ *
+ * @param ctx Context, or NULL for default context.
+ * @param crs_auth_name CRS authority name, or NULL.
+ * @param datum_auth_name Datum authority name (must not be NULL)
+ * @param datum_code Datum code (must not be NULL)
+ * @param crs_type "geographic 2D", "geographic 3D", "geocentric" or NULL
+ * @return a result set that must be unreferenced with
+ * proj_obj_list_destroy(), or NULL in case of error.
+ */
+PJ_OBJ_LIST *proj_obj_query_geodetic_crs_from_datum(PJ_CONTEXT *ctx,
+                                                    const char *crs_auth_name,
+                                                    const char *datum_auth_name,
+                                                    const char *datum_code,
+                                                    const char *crs_type) {
+    assert(datum_auth_name);
+    assert(datum_code);
+    SANITIZE_CTX(ctx);
+    try {
+        auto factory = AuthorityFactory::create(
+            getDBcontext(ctx), crs_auth_name ? crs_auth_name : "");
+        auto res = factory->createGeodeticCRSFromDatum(
+            datum_auth_name, datum_code, crs_type ? crs_type : "");
+        std::vector<IdentifiedObjectNNPtr> objects;
+        for (const auto &obj : res) {
+            objects.push_back(obj);
+        }
+        return new PJ_OBJ_LIST(std::move(objects));
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Drops a reference on an object.
+ *
+ * This method should be called one and exactly one for each function
+ * returning a PJ_OBJ*
+ *
+ * @param obj Object, or NULL.
+ */
+void proj_obj_destroy(PJ_OBJ *obj) { delete obj; }
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static AuthorityFactory::ObjectType
+convertPJObjectTypeToObjectType(PJ_OBJ_TYPE type, bool &valid) {
+    valid = true;
+    AuthorityFactory::ObjectType cppType = AuthorityFactory::ObjectType::CRS;
+    switch (type) {
+    case PJ_OBJ_TYPE_ELLIPSOID:
+        cppType = AuthorityFactory::ObjectType::ELLIPSOID;
+        break;
+
+    case PJ_OBJ_TYPE_PRIME_MERIDIAN:
+        cppType = AuthorityFactory::ObjectType::PRIME_MERIDIAN;
+        break;
+
+    case PJ_OBJ_TYPE_GEODETIC_REFERENCE_FRAME:
+    case PJ_OBJ_TYPE_DYNAMIC_GEODETIC_REFERENCE_FRAME:
+        cppType = AuthorityFactory::ObjectType::GEODETIC_REFERENCE_FRAME;
+        break;
+
+    case PJ_OBJ_TYPE_VERTICAL_REFERENCE_FRAME:
+    case PJ_OBJ_TYPE_DYNAMIC_VERTICAL_REFERENCE_FRAME:
+        cppType = AuthorityFactory::ObjectType::VERTICAL_REFERENCE_FRAME;
+        break;
+
+    case PJ_OBJ_TYPE_DATUM_ENSEMBLE:
+        cppType = AuthorityFactory::ObjectType::DATUM;
+        break;
+
+    case PJ_OBJ_TYPE_CRS:
+        cppType = AuthorityFactory::ObjectType::CRS;
+        break;
+
+    case PJ_OBJ_TYPE_GEODETIC_CRS:
+        cppType = AuthorityFactory::ObjectType::GEODETIC_CRS;
+        break;
+
+    case PJ_OBJ_TYPE_GEOCENTRIC_CRS:
+        cppType = AuthorityFactory::ObjectType::GEOCENTRIC_CRS;
+        break;
+
+    case PJ_OBJ_TYPE_GEOGRAPHIC_CRS:
+        cppType = AuthorityFactory::ObjectType::GEOGRAPHIC_CRS;
+        break;
+
+    case PJ_OBJ_TYPE_GEOGRAPHIC_2D_CRS:
+        cppType = AuthorityFactory::ObjectType::GEOGRAPHIC_2D_CRS;
+        break;
+
+    case PJ_OBJ_TYPE_GEOGRAPHIC_3D_CRS:
+        cppType = AuthorityFactory::ObjectType::GEOGRAPHIC_3D_CRS;
+        break;
+
+    case PJ_OBJ_TYPE_VERTICAL_CRS:
+        cppType = AuthorityFactory::ObjectType::VERTICAL_CRS;
+        break;
+
+    case PJ_OBJ_TYPE_PROJECTED_CRS:
+        cppType = AuthorityFactory::ObjectType::PROJECTED_CRS;
+        break;
+
+    case PJ_OBJ_TYPE_COMPOUND_CRS:
+        cppType = AuthorityFactory::ObjectType::COMPOUND_CRS;
+        break;
+
+    case PJ_OBJ_TYPE_ENGINEERING_CRS:
+        valid = false;
+        break;
+
+    case PJ_OBJ_TYPE_TEMPORAL_CRS:
+        valid = false;
+        break;
+
+    case PJ_OBJ_TYPE_BOUND_CRS:
+        valid = false;
+        break;
+
+    case PJ_OBJ_TYPE_OTHER_CRS:
+        cppType = AuthorityFactory::ObjectType::CRS;
+        break;
+
+    case PJ_OBJ_TYPE_CONVERSION:
+        cppType = AuthorityFactory::ObjectType::CONVERSION;
+        break;
+
+    case PJ_OBJ_TYPE_TRANSFORMATION:
+        cppType = AuthorityFactory::ObjectType::TRANSFORMATION;
+        break;
+
+    case PJ_OBJ_TYPE_CONCATENATED_OPERATION:
+        cppType = AuthorityFactory::ObjectType::CONCATENATED_OPERATION;
+        break;
+
+    case PJ_OBJ_TYPE_OTHER_COORDINATE_OPERATION:
+        cppType = AuthorityFactory::ObjectType::COORDINATE_OPERATION;
+        break;
+
+    case PJ_OBJ_TYPE_UNKNOWN:
+        valid = false;
+        break;
+    }
+    return cppType;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return a list of objects by their name.
+ *
+ * @param ctx Context, or NULL for default context.
+ * @param auth_name Authority name, used to restrict the search.
+ * Or NULL for all authorities.
+ * @param searchedName Searched name. Must be at least 2 character long.
+ * @param types List of object types into which to search. If
+ * NULL, all object types will be searched.
+ * @param typesCount Number of elements in types, or 0 if types is NULL
+ * @param approximateMatch Whether approximate name identification is allowed.
+ * @param limitResultCount Maximum number of results to return.
+ * Or 0 for unlimited.
+ * @param options should be set to NULL for now
+ * @return a result set that must be unreferenced with
+ * proj_obj_list_destroy(), or NULL in case of error.
+ */
+PJ_OBJ_LIST *proj_obj_create_from_name(PJ_CONTEXT *ctx, const char *auth_name,
+                                       const char *searchedName,
+                                       const PJ_OBJ_TYPE *types,
+                                       size_t typesCount, int approximateMatch,
+                                       size_t limitResultCount,
+                                       const char *const *options) {
+    assert(searchedName);
+    assert((types != nullptr && typesCount > 0) ||
+           (types == nullptr && typesCount == 0));
+    (void)options;
+    SANITIZE_CTX(ctx);
+    try {
+        auto factory = AuthorityFactory::create(getDBcontext(ctx),
+                                                auth_name ? auth_name : "");
+        std::vector<AuthorityFactory::ObjectType> allowedTypes;
+        for (size_t i = 0; i < typesCount; ++i) {
+            bool valid = false;
+            auto type = convertPJObjectTypeToObjectType(types[i], valid);
+            if (valid) {
+                allowedTypes.push_back(type);
+            }
+        }
+        auto res = factory->createObjectsFromName(searchedName, allowedTypes,
+                                                  approximateMatch != 0,
+                                                  limitResultCount);
+        std::vector<IdentifiedObjectNNPtr> objects;
+        for (const auto &obj : res) {
+            objects.push_back(obj);
+        }
+        return new PJ_OBJ_LIST(std::move(objects));
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the type of an object.
+ *
+ * @param obj Object (must not be NULL)
+ * @return its type.
+ */
+PJ_OBJ_TYPE proj_obj_get_type(const PJ_OBJ *obj) {
+    assert(obj);
+    auto ptr = obj->obj.get();
+    if (dynamic_cast<Ellipsoid *>(ptr)) {
+        return PJ_OBJ_TYPE_ELLIPSOID;
+    }
+
+    if (dynamic_cast<PrimeMeridian *>(ptr)) {
+        return PJ_OBJ_TYPE_PRIME_MERIDIAN;
+    }
+
+    if (dynamic_cast<DynamicGeodeticReferenceFrame *>(ptr)) {
+        return PJ_OBJ_TYPE_DYNAMIC_GEODETIC_REFERENCE_FRAME;
+    }
+    if (dynamic_cast<GeodeticReferenceFrame *>(ptr)) {
+        return PJ_OBJ_TYPE_GEODETIC_REFERENCE_FRAME;
+    }
+    if (dynamic_cast<DynamicVerticalReferenceFrame *>(ptr)) {
+        return PJ_OBJ_TYPE_DYNAMIC_VERTICAL_REFERENCE_FRAME;
+    }
+    if (dynamic_cast<VerticalReferenceFrame *>(ptr)) {
+        return PJ_OBJ_TYPE_VERTICAL_REFERENCE_FRAME;
+    }
+    if (dynamic_cast<DatumEnsemble *>(ptr)) {
+        return PJ_OBJ_TYPE_DATUM_ENSEMBLE;
+    }
+
+    {
+        auto crs = dynamic_cast<GeographicCRS *>(ptr);
+        if (crs) {
+            if (crs->coordinateSystem()->axisList().size() == 2) {
+                return PJ_OBJ_TYPE_GEOGRAPHIC_2D_CRS;
+            } else {
+                return PJ_OBJ_TYPE_GEOGRAPHIC_3D_CRS;
+            }
+        }
+    }
+
+    {
+        auto crs = dynamic_cast<GeodeticCRS *>(ptr);
+        if (crs) {
+            if (crs->isGeocentric()) {
+                return PJ_OBJ_TYPE_GEOCENTRIC_CRS;
+            } else {
+                return PJ_OBJ_TYPE_GEODETIC_CRS;
+            }
+        }
+    }
+
+    if (dynamic_cast<VerticalCRS *>(ptr)) {
+        return PJ_OBJ_TYPE_VERTICAL_CRS;
+    }
+    if (dynamic_cast<ProjectedCRS *>(ptr)) {
+        return PJ_OBJ_TYPE_PROJECTED_CRS;
+    }
+    if (dynamic_cast<CompoundCRS *>(ptr)) {
+        return PJ_OBJ_TYPE_COMPOUND_CRS;
+    }
+    if (dynamic_cast<TemporalCRS *>(ptr)) {
+        return PJ_OBJ_TYPE_TEMPORAL_CRS;
+    }
+    if (dynamic_cast<EngineeringCRS *>(ptr)) {
+        return PJ_OBJ_TYPE_ENGINEERING_CRS;
+    }
+    if (dynamic_cast<BoundCRS *>(ptr)) {
+        return PJ_OBJ_TYPE_BOUND_CRS;
+    }
+    if (dynamic_cast<CRS *>(ptr)) {
+        return PJ_OBJ_TYPE_OTHER_CRS;
+    }
+
+    if (dynamic_cast<Conversion *>(ptr)) {
+        return PJ_OBJ_TYPE_CONVERSION;
+    }
+    if (dynamic_cast<Transformation *>(ptr)) {
+        return PJ_OBJ_TYPE_TRANSFORMATION;
+    }
+    if (dynamic_cast<ConcatenatedOperation *>(ptr)) {
+        return PJ_OBJ_TYPE_CONCATENATED_OPERATION;
+    }
+    if (dynamic_cast<CoordinateOperation *>(ptr)) {
+        return PJ_OBJ_TYPE_OTHER_COORDINATE_OPERATION;
+    }
+
+    return PJ_OBJ_TYPE_UNKNOWN;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return whether an object is deprecated.
+ *
+ * @param obj Object (must not be NULL)
+ * @return TRUE if it is deprecated, FALSE otherwise
+ */
+int proj_obj_is_deprecated(const PJ_OBJ *obj) {
+    assert(obj);
+    return obj->obj->isDeprecated();
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return a list of non-deprecated objects related to the passed one
+ *
+ * @param ctx Context, or NULL for default context.
+ * @param obj Object (of type CRS for now) for which non-deprecated objects
+ * must be searched. Must not be NULL
+ * @return a result set that must be unreferenced with
+ * proj_obj_list_destroy(), or NULL in case of error.
+ */
+PJ_OBJ_LIST *proj_obj_get_non_deprecated(PJ_CONTEXT *ctx, const PJ_OBJ *obj) {
+    assert(obj);
+    SANITIZE_CTX(ctx);
+    auto crs = dynamic_cast<const CRS *>(obj->obj.get());
+    if (!crs) {
+        return nullptr;
+    }
+    try {
+        std::vector<IdentifiedObjectNNPtr> objects;
+        auto res = crs->getNonDeprecated(getDBcontext(ctx));
+        for (const auto &resObj : res) {
+            objects.push_back(resObj);
+        }
+        return new PJ_OBJ_LIST(std::move(objects));
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return whether two objects are equivalent.
+ *
+ * @param obj Object (must not be NULL)
+ * @param other Other object (must not be NULL)
+ * @param criterion Comparison criterion
+ * @return TRUE if they are equivalent
+ */
+int proj_obj_is_equivalent_to(const PJ_OBJ *obj, const PJ_OBJ *other,
+                              PJ_COMPARISON_CRITERION criterion) {
+    assert(obj);
+    assert(other);
+
+    // Make sure that the C and C++ enumerations match
+    static_assert(static_cast<int>(PJ_COMP_STRICT) ==
+                      static_cast<int>(IComparable::Criterion::STRICT),
+                  "");
+    static_assert(static_cast<int>(PJ_COMP_EQUIVALENT) ==
+                      static_cast<int>(IComparable::Criterion::EQUIVALENT),
+                  "");
+    static_assert(
+        static_cast<int>(PJ_COMP_EQUIVALENT_EXCEPT_AXIS_ORDER_GEOGCRS) ==
+            static_cast<int>(
+                IComparable::Criterion::EQUIVALENT_EXCEPT_AXIS_ORDER_GEOGCRS),
+        "");
+
+    // Make sure we enumerate all values. If adding a new value, as we
+    // don't have a default clause, the compiler will warn.
+    switch (criterion) {
+    case PJ_COMP_STRICT:
+    case PJ_COMP_EQUIVALENT:
+    case PJ_COMP_EQUIVALENT_EXCEPT_AXIS_ORDER_GEOGCRS:
+        break;
+    }
+    const IComparable::Criterion cppCriterion =
+        static_cast<IComparable::Criterion>(criterion);
+    return obj->obj->isEquivalentTo(other->obj.get(), cppCriterion);
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return whether an object is a CRS
+ *
+ * @param obj Object (must not be NULL)
+ */
+int proj_obj_is_crs(const PJ_OBJ *obj) {
+    assert(obj);
+    return dynamic_cast<CRS *>(obj->obj.get()) != nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Get the name of an object.
+ *
+ * The lifetime of the returned string is the same as the input obj parameter.
+ *
+ * @param obj Object (must not be NULL)
+ * @return a string, or NULL in case of error or missing name.
+ */
+const char *proj_obj_get_name(const PJ_OBJ *obj) {
+    assert(obj);
+    const auto &desc = obj->obj->name()->description();
+    if (!desc.has_value()) {
+        return nullptr;
+    }
+    // The object will still be alived after the function call.
+    // cppcheck-suppress stlcstr
+    return desc->c_str();
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Get the authority name / codespace of an identifier of an object.
+ *
+ * The lifetime of the returned string is the same as the input obj parameter.
+ *
+ * @param obj Object (must not be NULL)
+ * @param index Index of the identifier. 0 = first identifier
+ * @return a string, or NULL in case of error or missing name.
+ */
+const char *proj_obj_get_id_auth_name(const PJ_OBJ *obj, int index) {
+    assert(obj);
+    const auto &ids = obj->obj->identifiers();
+    if (static_cast<size_t>(index) >= ids.size()) {
+        return nullptr;
+    }
+    const auto &codeSpace = ids[index]->codeSpace();
+    if (!codeSpace.has_value()) {
+        return nullptr;
+    }
+    // The object will still be alived after the function call.
+    // cppcheck-suppress stlcstr
+    return codeSpace->c_str();
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Get the code of an identifier of an object.
+ *
+ * The lifetime of the returned string is the same as the input obj parameter.
+ *
+ * @param obj Object (must not be NULL)
+ * @param index Index of the identifier. 0 = first identifier
+ * @return a string, or NULL in case of error or missing name.
+ */
+const char *proj_obj_get_id_code(const PJ_OBJ *obj, int index) {
+    assert(obj);
+    const auto &ids = obj->obj->identifiers();
+    if (static_cast<size_t>(index) >= ids.size()) {
+        return nullptr;
+    }
+    return ids[index]->code().c_str();
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Get a WKT representation of an object.
+ *
+ * The returned string is valid while the input obj parameter is valid,
+ * and until a next call to proj_obj_as_wkt() with the same input object.
+ *
+ * This function calls osgeo::proj::io::IWKTExportable::exportToWKT().
+ *
+ * This function may return NULL if the object is not compatible with an
+ * export to the requested type.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param obj Object (must not be NULL)
+ * @param type WKT version.
+ * @param options null-terminated list of options, or NULL. Currently
+ * supported options are:
+ * <ul>
+ * <li>MULTILINE=YES/NO. Defaults to YES, except for WKT1_ESRI</li>
+ * <li>INDENTATION_WIDTH=number. Defauls to 4 (when multiline output is
+ * on).</li>
+ * <li>OUTPUT_AXIS=AUTO/YES/NO. In AUTO mode, axis will be output for WKT2
+ * variants, for WKT1_GDAL for ProjectedCRS with easting/northing ordering
+ * (otherwise stripped), but not for WKT1_ESRI. Setting to YES will output
+ * them unconditionaly, and to NO will omit them unconditionaly.</li>
+ * </ul>
+ * @return a string, or NULL in case of error.
+ */
+const char *proj_obj_as_wkt(PJ_CONTEXT *ctx, const PJ_OBJ *obj,
+                            PJ_WKT_TYPE type, const char *const *options) {
+    SANITIZE_CTX(ctx);
+    assert(obj);
+
+    // Make sure that the C and C++ enumerations match
+    static_assert(static_cast<int>(PJ_WKT2_2015) ==
+                      static_cast<int>(WKTFormatter::Convention::WKT2_2015),
+                  "");
+    static_assert(
+        static_cast<int>(PJ_WKT2_2015_SIMPLIFIED) ==
+            static_cast<int>(WKTFormatter::Convention::WKT2_2015_SIMPLIFIED),
+        "");
+    static_assert(static_cast<int>(PJ_WKT2_2018) ==
+                      static_cast<int>(WKTFormatter::Convention::WKT2_2018),
+                  "");
+    static_assert(
+        static_cast<int>(PJ_WKT2_2018_SIMPLIFIED) ==
+            static_cast<int>(WKTFormatter::Convention::WKT2_2018_SIMPLIFIED),
+        "");
+    static_assert(static_cast<int>(PJ_WKT1_GDAL) ==
+                      static_cast<int>(WKTFormatter::Convention::WKT1_GDAL),
+                  "");
+    static_assert(static_cast<int>(PJ_WKT1_ESRI) ==
+                      static_cast<int>(WKTFormatter::Convention::WKT1_ESRI),
+                  "");
+    // Make sure we enumerate all values. If adding a new value, as we
+    // don't have a default clause, the compiler will warn.
+    switch (type) {
+    case PJ_WKT2_2015:
+    case PJ_WKT2_2015_SIMPLIFIED:
+    case PJ_WKT2_2018:
+    case PJ_WKT2_2018_SIMPLIFIED:
+    case PJ_WKT1_GDAL:
+    case PJ_WKT1_ESRI:
+        break;
+    }
+    const WKTFormatter::Convention convention =
+        static_cast<WKTFormatter::Convention>(type);
+    try {
+        auto dbContext = getDBcontextNoException(ctx, __FUNCTION__);
+        auto formatter = WKTFormatter::create(convention, dbContext);
+        for (auto iter = options; iter && iter[0]; ++iter) {
+            const char *value;
+            if ((value = getOptionValue(*iter, "MULTILINE="))) {
+                formatter->setMultiLine(ci_equal(value, "YES"));
+            } else if ((value = getOptionValue(*iter, "INDENTATION_WIDTH="))) {
+                formatter->setIndentationWidth(std::atoi(value));
+            } else if ((value = getOptionValue(*iter, "OUTPUT_AXIS="))) {
+                if (!ci_equal(value, "AUTO")) {
+                    formatter->setOutputAxis(
+                        ci_equal(value, "YES")
+                            ? WKTFormatter::OutputAxisRule::YES
+                            : WKTFormatter::OutputAxisRule::NO);
+                }
+            } else {
+                std::string msg("Unknown option :");
+                msg += *iter;
+                proj_log_error(ctx, __FUNCTION__, msg.c_str());
+                return nullptr;
+            }
+        }
+        obj->lastWKT = obj->obj->exportToWKT(formatter.get());
+        return obj->lastWKT.c_str();
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+        return nullptr;
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Get a PROJ string representation of an object.
+ *
+ * The returned string is valid while the input obj parameter is valid,
+ * and until a next call to proj_obj_as_proj_string() with the same input
+ * object.
+ *
+ * This function calls
+ * osgeo::proj::io::IPROJStringExportable::exportToPROJString().
+ *
+ * This function may return NULL if the object is not compatible with an
+ * export to the requested type.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param obj Object (must not be NULL)
+ * @param type PROJ String version.
+ * @param options NULL-terminated list of strings with "KEY=VALUE" format. or
+ * NULL.
+ * The currently recognized option is USE_ETMERC=YES to use
+ * +proj=etmerc instead of +proj=tmerc (or USE_ETMERC=NO to disable implicit
+ * use of etmerc by utm conversions)
+ * @return a string, or NULL in case of error.
+ */
+const char *proj_obj_as_proj_string(PJ_CONTEXT *ctx, const PJ_OBJ *obj,
+                                    PJ_PROJ_STRING_TYPE type,
+                                    const char *const *options) {
+    SANITIZE_CTX(ctx);
+    assert(obj);
+    auto exportable =
+        dynamic_cast<const IPROJStringExportable *>(obj->obj.get());
+    if (!exportable) {
+        proj_log_error(ctx, __FUNCTION__, "Object type not exportable to PROJ");
+        return nullptr;
+    }
+    // Make sure that the C and C++ enumeration match
+    static_assert(static_cast<int>(PJ_PROJ_5) ==
+                      static_cast<int>(PROJStringFormatter::Convention::PROJ_5),
+                  "");
+    static_assert(static_cast<int>(PJ_PROJ_4) ==
+                      static_cast<int>(PROJStringFormatter::Convention::PROJ_4),
+                  "");
+    // Make sure we enumerate all values. If adding a new value, as we
+    // don't have a default clause, the compiler will warn.
+    switch (type) {
+    case PJ_PROJ_5:
+    case PJ_PROJ_4:
+        break;
+    }
+    const PROJStringFormatter::Convention convention =
+        static_cast<PROJStringFormatter::Convention>(type);
+    auto dbContext = getDBcontextNoException(ctx, __FUNCTION__);
+    try {
+        auto formatter = PROJStringFormatter::create(convention, dbContext);
+        if (options != nullptr && options[0] != nullptr) {
+            if (ci_equal(options[0], "USE_ETMERC=YES")) {
+                formatter->setUseETMercForTMerc(true);
+            } else if (ci_equal(options[0], "USE_ETMERC=NO")) {
+                formatter->setUseETMercForTMerc(false);
+            }
+        }
+        obj->lastPROJString = exportable->exportToPROJString(formatter.get());
+        return obj->lastPROJString.c_str();
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+        return nullptr;
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the area of use of an object.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param obj Object (must not be NULL)
+ * @param out_west_lon_degree Pointer to a double to receive the west longitude
+ * (in degrees). Or NULL. If the returned value is -1000, the bounding box is
+ * unknown.
+ * @param out_south_lat_degree Pointer to a double to receive the south latitude
+ * (in degrees). Or NULL. If the returned value is -1000, the bounding box is
+ * unknown.
+ * @param out_east_lon_degree Pointer to a double to receive the east longitude
+ * (in degrees). Or NULL. If the returned value is -1000, the bounding box is
+ * unknown.
+ * @param out_north_lat_degree Pointer to a double to receive the north latitude
+ * (in degrees). Or NULL. If the returned value is -1000, the bounding box is
+ * unknown.
+ * @param out_area_name Pointer to a string to receive the name of the area of
+ * use. Or NULL. *p_area_name is valid while obj is valid itself.
+ * @return TRUE in case of success, FALSE in case of error or if the area
+ * of use is unknown.
+ */
+int proj_obj_get_area_of_use(PJ_CONTEXT *ctx, const PJ_OBJ *obj,
+                             double *out_west_lon_degree,
+                             double *out_south_lat_degree,
+                             double *out_east_lon_degree,
+                             double *out_north_lat_degree,
+                             const char **out_area_name) {
+    (void)ctx;
+    if (out_area_name) {
+        *out_area_name = nullptr;
+    }
+    auto objectUsage = dynamic_cast<const ObjectUsage *>(obj->obj.get());
+    if (!objectUsage) {
+        return false;
+    }
+    const auto &domains = objectUsage->domains();
+    if (domains.empty()) {
+        return false;
+    }
+    const auto &extent = domains[0]->domainOfValidity();
+    if (!extent) {
+        return false;
+    }
+    const auto &desc = extent->description();
+    if (desc.has_value() && out_area_name) {
+        *out_area_name = desc->c_str();
+    }
+
+    const auto &geogElements = extent->geographicElements();
+    if (!geogElements.empty()) {
+        auto bbox =
+            dynamic_cast<const GeographicBoundingBox *>(geogElements[0].get());
+        if (bbox) {
+            if (out_west_lon_degree) {
+                *out_west_lon_degree = bbox->westBoundLongitude();
+            }
+            if (out_south_lat_degree) {
+                *out_south_lat_degree = bbox->southBoundLatitude();
+            }
+            if (out_east_lon_degree) {
+                *out_east_lon_degree = bbox->eastBoundLongitude();
+            }
+            if (out_north_lat_degree) {
+                *out_north_lat_degree = bbox->northBoundLatitude();
+            }
+            return true;
+        }
+    }
+    if (out_west_lon_degree) {
+        *out_west_lon_degree = -1000;
+    }
+    if (out_south_lat_degree) {
+        *out_south_lat_degree = -1000;
+    }
+    if (out_east_lon_degree) {
+        *out_east_lon_degree = -1000;
+    }
+    if (out_north_lat_degree) {
+        *out_north_lat_degree = -1000;
+    }
+    return true;
+}
+
+// ---------------------------------------------------------------------------
+
+static const GeodeticCRS *extractGeodeticCRS(PJ_CONTEXT *ctx, const PJ_OBJ *crs,
+                                             const char *fname) {
+    assert(crs);
+    auto l_crs = dynamic_cast<const CRS *>(crs->obj.get());
+    if (!l_crs) {
+        proj_log_error(ctx, fname, "Object is not a CRS");
+        return nullptr;
+    }
+    auto geodCRS = l_crs->extractGeodeticCRSRaw();
+    if (!geodCRS) {
+        proj_log_error(ctx, fname, "CRS has no geodetic CRS");
+    }
+    return geodCRS;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Get the geodeticCRS / geographicCRS from a CRS
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after
+ * use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param crs Objet of type CRS (must not be NULL)
+ * @return Object that must be unreferenced with proj_obj_destroy(), or NULL
+ * in case of error.
+ */
+PJ_OBJ *proj_obj_crs_get_geodetic_crs(PJ_CONTEXT *ctx, const PJ_OBJ *crs) {
+    SANITIZE_CTX(ctx);
+    auto geodCRS = extractGeodeticCRS(ctx, crs, __FUNCTION__);
+    if (!geodCRS) {
+        return nullptr;
+    }
+    return PJ_OBJ::create(NN_NO_CHECK(nn_dynamic_pointer_cast<IdentifiedObject>(
+        geodCRS->shared_from_this())));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Get a CRS component from a CompoundCRS
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after
+ * use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param crs Objet of type CRS (must not be NULL)
+ * @param index Index of the CRS component (typically 0 = horizontal, 1 =
+ * vertical)
+ * @return Object that must be unreferenced with proj_obj_destroy(), or NULL
+ * in case of error.
+ */
+PJ_OBJ *proj_obj_crs_get_sub_crs(PJ_CONTEXT *ctx, const PJ_OBJ *crs,
+                                 int index) {
+    SANITIZE_CTX(ctx);
+    assert(crs);
+    auto l_crs = dynamic_cast<CompoundCRS *>(crs->obj.get());
+    if (!l_crs) {
+        proj_log_error(ctx, __FUNCTION__, "Object is not a CompoundCRS");
+        return nullptr;
+    }
+    const auto &components = l_crs->componentReferenceSystems();
+    if (static_cast<size_t>(index) >= components.size()) {
+        return nullptr;
+    }
+    return PJ_OBJ::create(components[index]);
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns a BoundCRS
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after
+ * use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param base_crs Base CRS (must not be NULL)
+ * @param hub_crs Hub CRS (must not be NULL)
+ * @param transformation Transformation (must not be NULL)
+ * @return Object that must be unreferenced with proj_obj_destroy(), or NULL
+ * in case of error.
+ */
+PJ_OBJ *proj_obj_crs_create_bound_crs(PJ_CONTEXT *ctx, const PJ_OBJ *base_crs,
+                                      const PJ_OBJ *hub_crs,
+                                      const PJ_OBJ *transformation) {
+    SANITIZE_CTX(ctx);
+    assert(base_crs);
+    assert(hub_crs);
+    assert(transformation);
+    auto l_base_crs = util::nn_dynamic_pointer_cast<CRS>(base_crs->obj);
+    if (!l_base_crs) {
+        proj_log_error(ctx, __FUNCTION__, "base_crs is not a CRS");
+        return nullptr;
+    }
+    auto l_hub_crs = util::nn_dynamic_pointer_cast<CRS>(hub_crs->obj);
+    if (!l_hub_crs) {
+        proj_log_error(ctx, __FUNCTION__, "hub_crs is not a CRS");
+        return nullptr;
+    }
+    auto l_transformation =
+        util::nn_dynamic_pointer_cast<Transformation>(transformation->obj);
+    if (!l_transformation) {
+        proj_log_error(ctx, __FUNCTION__, "transformation is not a CRS");
+        return nullptr;
+    }
+    try {
+        return PJ_OBJ::create(BoundCRS::create(NN_NO_CHECK(l_base_crs),
+                                               NN_NO_CHECK(l_hub_crs),
+                                               NN_NO_CHECK(l_transformation)));
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+        return nullptr;
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns potentially
+ * a BoundCRS, with a transformation to EPSG:4326, wrapping this CRS
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after
+ * use.
+ * It should be used by at most one thread at a time.
+ *
+ * This is the same as method
+ * osgeo::proj::crs::CRS::createBoundCRSToWGS84IfPossible()
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param crs Objet of type CRS (must not be NULL)
+ * @param options null-terminated list of options, or NULL. Currently
+ * supported options are:
+ * <ul>
+ * <li>ALLOW_INTERMEDIATE_CRS=YES/NO. Defaults to NO. When set to YES,
+ * intermediate CRS may be considered when computing the possible
+ * tranformations. Slower.</li>
+ * </ul>
+ * @return Object that must be unreferenced with proj_obj_destroy(), or NULL
+ * in case of error.
+ */
+PJ_OBJ *proj_obj_crs_create_bound_crs_to_WGS84(PJ_CONTEXT *ctx,
+                                               const PJ_OBJ *crs,
+                                               const char *const *options) {
+    SANITIZE_CTX(ctx);
+    assert(crs);
+    auto l_crs = dynamic_cast<const CRS *>(crs->obj.get());
+    if (!l_crs) {
+        proj_log_error(ctx, __FUNCTION__, "Object is not a CRS");
+        return nullptr;
+    }
+    auto dbContext = getDBcontextNoException(ctx, __FUNCTION__);
+    try {
+        bool allowIntermediateCRS = false;
+        for (auto iter = options; iter && iter[0]; ++iter) {
+            const char *value;
+            if ((value = getOptionValue(*iter, "ALLOW_INTERMEDIATE_CRS="))) {
+                allowIntermediateCRS = ci_equal(value, "YES");
+            } else {
+                std::string msg("Unknown option :");
+                msg += *iter;
+                proj_log_error(ctx, __FUNCTION__, msg.c_str());
+                return nullptr;
+            }
+        }
+        return PJ_OBJ::create(l_crs->createBoundCRSToWGS84IfPossible(
+            dbContext, allowIntermediateCRS));
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+        return nullptr;
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Get the ellipsoid from a CRS or a GeodeticReferenceFrame.
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after
+ * use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param obj Objet of type CRS or GeodeticReferenceFrame (must not be NULL)
+ * @return Object that must be unreferenced with proj_obj_destroy(), or NULL
+ * in case of error.
+ */
+PJ_OBJ *proj_obj_get_ellipsoid(PJ_CONTEXT *ctx, const PJ_OBJ *obj) {
+    SANITIZE_CTX(ctx);
+    auto ptr = obj->obj.get();
+    if (dynamic_cast<const CRS *>(ptr)) {
+        auto geodCRS = extractGeodeticCRS(ctx, obj, __FUNCTION__);
+        if (geodCRS) {
+            return PJ_OBJ::create(geodCRS->ellipsoid());
+        }
+    } else {
+        auto datum = dynamic_cast<const GeodeticReferenceFrame *>(ptr);
+        if (datum) {
+            return PJ_OBJ::create(datum->ellipsoid());
+        }
+    }
+    proj_log_error(ctx, __FUNCTION__,
+                   "Object is not a CRS or GeodeticReferenceFrame");
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Get the horizontal datum from a CRS
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after
+ * use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param crs Objet of type CRS (must not be NULL)
+ * @return Object that must be unreferenced with proj_obj_destroy(), or NULL
+ * in case of error.
+ */
+PJ_OBJ *proj_obj_crs_get_horizontal_datum(PJ_CONTEXT *ctx, const PJ_OBJ *crs) {
+    SANITIZE_CTX(ctx);
+    auto geodCRS = extractGeodeticCRS(ctx, crs, __FUNCTION__);
+    if (!geodCRS) {
+        return nullptr;
+    }
+    const auto &datum = geodCRS->datum();
+    if (datum) {
+        return PJ_OBJ::create(NN_NO_CHECK(datum));
+    }
+
+    const auto &datumEnsemble = geodCRS->datumEnsemble();
+    if (datumEnsemble) {
+        return PJ_OBJ::create(NN_NO_CHECK(datumEnsemble));
+    }
+    proj_log_error(ctx, __FUNCTION__, "CRS has no datum");
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return ellipsoid parameters.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param ellipsoid Object of type Ellipsoid (must not be NULL)
+ * @param out_semi_major_metre Pointer to a value to store the semi-major axis
+ * in
+ * metre. or NULL
+ * @param out_semi_minor_metre Pointer to a value to store the semi-minor axis
+ * in
+ * metre. or NULL
+ * @param out_is_semi_minor_computed Pointer to a boolean value to indicate if
+ * the
+ * semi-minor value was computed. If FALSE, its value comes from the
+ * definition. or NULL
+ * @param out_inv_flattening Pointer to a value to store the inverse
+ * flattening. or NULL
+ * @return TRUE in case of success.
+ */
+int proj_obj_ellipsoid_get_parameters(PJ_CONTEXT *ctx, const PJ_OBJ *ellipsoid,
+                                      double *out_semi_major_metre,
+                                      double *out_semi_minor_metre,
+                                      int *out_is_semi_minor_computed,
+                                      double *out_inv_flattening) {
+    SANITIZE_CTX(ctx);
+    assert(ellipsoid);
+    auto l_ellipsoid = dynamic_cast<const Ellipsoid *>(ellipsoid->obj.get());
+    if (!l_ellipsoid) {
+        proj_log_error(ctx, __FUNCTION__, "Object is not a Ellipsoid");
+        return FALSE;
+    }
+
+    if (out_semi_major_metre) {
+        *out_semi_major_metre = l_ellipsoid->semiMajorAxis().getSIValue();
+    }
+    if (out_semi_minor_metre) {
+        *out_semi_minor_metre =
+            l_ellipsoid->computeSemiMinorAxis().getSIValue();
+    }
+    if (out_is_semi_minor_computed) {
+        *out_is_semi_minor_computed =
+            !(l_ellipsoid->semiMinorAxis().has_value());
+    }
+    if (out_inv_flattening) {
+        *out_inv_flattening = l_ellipsoid->computedInverseFlattening();
+    }
+    return TRUE;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Get the prime meridian of a CRS or a GeodeticReferenceFrame.
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after
+ * use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param obj Objet of type CRS or GeodeticReferenceFrame (must not be NULL)
+ * @return Object that must be unreferenced with proj_obj_destroy(), or NULL
+ * in case of error.
+ */
+
+PJ_OBJ *proj_obj_get_prime_meridian(PJ_CONTEXT *ctx, const PJ_OBJ *obj) {
+    SANITIZE_CTX(ctx);
+    auto ptr = obj->obj.get();
+    if (dynamic_cast<CRS *>(ptr)) {
+        auto geodCRS = extractGeodeticCRS(ctx, obj, __FUNCTION__);
+        if (geodCRS) {
+            return PJ_OBJ::create(geodCRS->primeMeridian());
+        }
+    } else {
+        auto datum = dynamic_cast<const GeodeticReferenceFrame *>(ptr);
+        if (datum) {
+            return PJ_OBJ::create(datum->primeMeridian());
+        }
+    }
+    proj_log_error(ctx, __FUNCTION__,
+                   "Object is not a CRS or GeodeticReferenceFrame");
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return prime meridian parameters.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param prime_meridian Object of type PrimeMeridian (must not be NULL)
+ * @param out_longitude Pointer to a value to store the longitude of the prime
+ * meridian, in its native unit. or NULL
+ * @param out_unit_conv_factor Pointer to a value to store the conversion
+ * factor of the prime meridian longitude unit to radian. or NULL
+ * @param out_unit_name Pointer to a string value to store the unit name.
+ * or NULL
+ * @return TRUE in case of success.
+ */
+int proj_obj_prime_meridian_get_parameters(PJ_CONTEXT *ctx,
+                                           const PJ_OBJ *prime_meridian,
+                                           double *out_longitude,
+                                           double *out_unit_conv_factor,
+                                           const char **out_unit_name) {
+    SANITIZE_CTX(ctx);
+    assert(prime_meridian);
+    auto l_pm = dynamic_cast<const PrimeMeridian *>(prime_meridian->obj.get());
+    if (!l_pm) {
+        proj_log_error(ctx, __FUNCTION__, "Object is not a PrimeMeridian");
+        return false;
+    }
+    const auto &longitude = l_pm->longitude();
+    if (out_longitude) {
+        *out_longitude = longitude.value();
+    }
+    const auto &unit = longitude.unit();
+    if (out_unit_conv_factor) {
+        *out_unit_conv_factor = unit.conversionToSI();
+    }
+    if (out_unit_name) {
+        *out_unit_name = unit.name().c_str();
+    }
+    return true;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the base CRS of a BoundCRS or a DerivedCRS/ProjectedCRS, or
+ * the source CRS of a CoordinateOperation.
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after
+ * use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param obj Objet of type BoundCRS or CoordinateOperation (must not be NULL)
+ * @return Object that must be unreferenced with proj_obj_destroy(), or NULL
+ * in case of error, or missing source CRS.
+ */
+PJ_OBJ *proj_obj_get_source_crs(PJ_CONTEXT *ctx, const PJ_OBJ *obj) {
+    SANITIZE_CTX(ctx);
+    assert(obj);
+    auto ptr = obj->obj.get();
+    auto boundCRS = dynamic_cast<const BoundCRS *>(ptr);
+    if (boundCRS) {
+        return PJ_OBJ::create(boundCRS->baseCRS());
+    }
+    auto derivedCRS = dynamic_cast<const DerivedCRS *>(ptr);
+    if (derivedCRS) {
+        return PJ_OBJ::create(derivedCRS->baseCRS());
+    }
+    auto co = dynamic_cast<const CoordinateOperation *>(ptr);
+    if (co) {
+        auto sourceCRS = co->sourceCRS();
+        if (sourceCRS) {
+            return PJ_OBJ::create(NN_NO_CHECK(sourceCRS));
+        }
+        return nullptr;
+    }
+    proj_log_error(ctx, __FUNCTION__,
+                   "Object is not a BoundCRS or a CoordinateOperation");
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the hub CRS of a BoundCRS or the target CRS of a
+ * CoordinateOperation.
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after
+ * use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param obj Objet of type BoundCRS or CoordinateOperation (must not be NULL)
+ * @return Object that must be unreferenced with proj_obj_destroy(), or NULL
+ * in case of error, or missing target CRS.
+ */
+PJ_OBJ *proj_obj_get_target_crs(PJ_CONTEXT *ctx, const PJ_OBJ *obj) {
+    SANITIZE_CTX(ctx);
+    assert(obj);
+    auto ptr = obj->obj.get();
+    auto boundCRS = dynamic_cast<const BoundCRS *>(ptr);
+    if (boundCRS) {
+        return PJ_OBJ::create(boundCRS->hubCRS());
+    }
+    auto co = dynamic_cast<const CoordinateOperation *>(ptr);
+    if (co) {
+        auto targetCRS = co->targetCRS();
+        if (targetCRS) {
+            return PJ_OBJ::create(NN_NO_CHECK(targetCRS));
+        }
+        return nullptr;
+    }
+    proj_log_error(ctx, __FUNCTION__,
+                   "Object is not a BoundCRS or a CoordinateOperation");
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Identify the CRS with reference CRSs.
+ *
+ * The candidate CRSs are either hard-coded, or looked in the database when
+ * authorityFactory is not null.
+ *
+ * The method returns a list of matching reference CRS, and the percentage
+ * (0-100) of confidence in the match. The list is sorted by decreasing
+ * confidence.
+ *
+ * 100% means that the name of the reference entry
+ * perfectly matches the CRS name, and both are equivalent. In which case a
+ * single result is returned.
+ * 90% means that CRS are equivalent, but the names are not exactly the same.
+ * 70% means that CRS are equivalent), but the names do not match at all.
+ * 25% means that the CRS are not equivalent, but there is some similarity in
+ * the names.
+ * Other confidence values may be returned by some specialized implementations.
+ *
+ * This is implemented for GeodeticCRS, ProjectedCRS, VerticalCRS and
+ * CompoundCRS.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param obj Object of type CRS. Must not be NULL
+ * @param auth_name Authority name, or NULL for all authorities
+ * @param options Placeholder for future options. Should be set to NULL.
+ * @param out_confidence Output parameter. Pointer to an array of integers that
+ * will be allocated by the function and filled with the confidence values
+ * (0-100). There are as many elements in this array as
+ * proj_obj_list_get_count()
+ * returns on the return value of this function. *confidence should be
+ * released with proj_int_list_destroy().
+ * @return a list of matching reference CRS, or nullptr in case of error.
+ */
+PJ_OBJ_LIST *proj_obj_identify(PJ_CONTEXT *ctx, const PJ_OBJ *obj,
+                               const char *auth_name,
+                               const char *const *options,
+                               int **out_confidence) {
+    SANITIZE_CTX(ctx);
+    assert(obj);
+    (void)options;
+    if (out_confidence) {
+        *out_confidence = nullptr;
+    }
+    auto ptr = obj->obj.get();
+    auto crs = dynamic_cast<const CRS *>(ptr);
+    if (!crs) {
+        proj_log_error(ctx, __FUNCTION__, "Object is not a CRS");
+    } else {
+        int *confidenceTemp = nullptr;
+        try {
+            auto factory = AuthorityFactory::create(getDBcontext(ctx),
+                                                    auth_name ? auth_name : "");
+            auto res = crs->identify(factory);
+            std::vector<IdentifiedObjectNNPtr> objects;
+            confidenceTemp = out_confidence ? new int[res.size()] : nullptr;
+            size_t i = 0;
+            for (const auto &pair : res) {
+                objects.push_back(pair.first);
+                if (confidenceTemp) {
+                    confidenceTemp[i] = pair.second;
+                    ++i;
+                }
+            }
+            auto ret = internal::make_unique<PJ_OBJ_LIST>(std::move(objects));
+            if (out_confidence) {
+                *out_confidence = confidenceTemp;
+                confidenceTemp = nullptr;
+            }
+            return ret.release();
+        } catch (const std::exception &e) {
+            delete[] confidenceTemp;
+            proj_log_error(ctx, __FUNCTION__, e.what());
+        }
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Free an array of integer. */
+void proj_int_list_destroy(int *list) { delete[] list; }
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the list of authorities used in the database.
+ *
+ * The returned list is NULL terminated and must be freed with
+ * proj_string_list_destroy().
+ *
+ * @param ctx PROJ context, or NULL for default context
+ *
+ * @return a NULL terminated list of NUL-terminated strings that must be
+ * freed with proj_string_list_destroy(), or NULL in case of error.
+ */
+PROJ_STRING_LIST proj_get_authorities_from_database(PJ_CONTEXT *ctx) {
+    SANITIZE_CTX(ctx);
+    try {
+        return to_string_list(getDBcontext(ctx)->getAuthorities());
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns the set of authority codes of the given object type.
+ *
+ * The returned list is NULL terminated and must be freed with
+ * proj_string_list_destroy().
+ *
+ * @param ctx PROJ context, or NULL for default context.
+ * @param auth_name Authority name (must not be NULL)
+ * @param type Object type.
+ * @param allow_deprecated whether we should return deprecated objects as well.
+ *
+ * @return a NULL terminated list of NUL-terminated strings that must be
+ * freed with proj_string_list_destroy(), or NULL in case of error.
+ */
+PROJ_STRING_LIST proj_get_codes_from_database(PJ_CONTEXT *ctx,
+                                              const char *auth_name,
+                                              PJ_OBJ_TYPE type,
+                                              int allow_deprecated) {
+    assert(auth_name);
+    SANITIZE_CTX(ctx);
+    try {
+        auto factory = AuthorityFactory::create(getDBcontext(ctx), auth_name);
+        bool valid = false;
+        auto typeInternal = convertPJObjectTypeToObjectType(type, valid);
+        if (!valid) {
+            return nullptr;
+        }
+        return to_string_list(
+            factory->getAuthorityCodes(typeInternal, allow_deprecated != 0));
+
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+/** Free a list of NULL terminated strings. */
+void proj_string_list_destroy(PROJ_STRING_LIST list) {
+    if (list) {
+        for (size_t i = 0; list[i] != nullptr; i++) {
+            delete[] list[i];
+        }
+        delete[] list;
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the Conversion of a DerivedCRS (such as a ProjectedCRS),
+ * or the Transformation from the baseCRS to the hubCRS of a BoundCRS
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after
+ * use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param crs Objet of type DerivedCRS or BoundCRSs (must not be NULL)
+ * @return Object of type SingleOperation that must be unreferenced with
+ * proj_obj_destroy(), or NULL in case of error.
+ */
+PJ_OBJ *proj_obj_crs_get_coordoperation(PJ_CONTEXT *ctx, const PJ_OBJ *crs) {
+    SANITIZE_CTX(ctx);
+    assert(crs);
+    SingleOperationPtr co;
+
+    auto derivedCRS = dynamic_cast<const DerivedCRS *>(crs->obj.get());
+    if (derivedCRS) {
+        co = derivedCRS->derivingConversion().as_nullable();
+    } else {
+        auto boundCRS = dynamic_cast<const BoundCRS *>(crs->obj.get());
+        if (boundCRS) {
+            co = boundCRS->transformation().as_nullable();
+        } else {
+            proj_log_error(ctx, __FUNCTION__,
+                           "Object is not a DerivedCRS or BoundCRS");
+            return nullptr;
+        }
+    }
+
+    return PJ_OBJ::create(NN_NO_CHECK(co));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return informatin on the operation method of the SingleOperation.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param coordoperation Objet of type SingleOperation (typically a Conversion
+ * or Transformation) (must not be NULL)
+ * @param out_method_name Pointer to a string value to store the method
+ * (projection) name. or NULL
+ * @param out_method_auth_name Pointer to a string value to store the method
+ * authority name. or NULL
+ * @param out_method_code Pointer to a string value to store the method
+ * code. or NULL
+ * @return TRUE in case of success.
+ */
+int proj_coordoperation_get_method_info(PJ_CONTEXT *ctx,
+                                        const PJ_OBJ *coordoperation,
+                                        const char **out_method_name,
+                                        const char **out_method_auth_name,
+                                        const char **out_method_code) {
+    SANITIZE_CTX(ctx);
+    assert(coordoperation);
+
+    auto singleOp =
+        dynamic_cast<const SingleOperation *>(coordoperation->obj.get());
+    if (!singleOp) {
+        proj_log_error(ctx, __FUNCTION__,
+                       "Object is not a DerivedCRS or BoundCRS");
+        return false;
+    }
+
+    const auto &method = singleOp->method();
+    const auto &method_ids = method->identifiers();
+    if (out_method_name) {
+        *out_method_name = method->name()->description()->c_str();
+    }
+    if (out_method_auth_name) {
+        if (!method_ids.empty()) {
+            *out_method_auth_name = method_ids[0]->codeSpace()->c_str();
+        } else {
+            *out_method_auth_name = nullptr;
+        }
+    }
+    if (out_method_code) {
+        if (!method_ids.empty()) {
+            *out_method_code = method_ids[0]->code().c_str();
+        } else {
+            *out_method_code = nullptr;
+        }
+    }
+    return true;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static PropertyMap createPropertyMapName(const char *c_name) {
+    std::string name(c_name ? c_name : "unnamed");
+    PropertyMap properties;
+    if (ends_with(name, " (deprecated)")) {
+        name.resize(name.size() - strlen(" (deprecated)"));
+        properties.set(common::IdentifiedObject::DEPRECATED_KEY, true);
+    }
+    return properties.set(common::IdentifiedObject::NAME_KEY, name);
+}
+
+// ---------------------------------------------------------------------------
+
+static UnitOfMeasure createLinearUnit(const char *name, double convFactor,
+                                      const char *unit_auth_name = nullptr,
+                                      const char *unit_code = nullptr) {
+    return name == nullptr
+               ? UnitOfMeasure::METRE
+               : UnitOfMeasure(name, convFactor, UnitOfMeasure::Type::LINEAR,
+                               unit_auth_name ? unit_auth_name : "",
+                               unit_code ? unit_code : "");
+}
+
+// ---------------------------------------------------------------------------
+
+static UnitOfMeasure createAngularUnit(const char *name, double convFactor,
+                                       const char *unit_auth_name = nullptr,
+                                       const char *unit_code = nullptr) {
+    return name ? (ci_equal(name, "degree")
+                       ? UnitOfMeasure::DEGREE
+                       : ci_equal(name, "grad")
+                             ? UnitOfMeasure::GRAD
+                             : UnitOfMeasure(name, convFactor,
+                                             UnitOfMeasure::Type::ANGULAR,
+                                             unit_auth_name ? unit_auth_name
+                                                            : "",
+                                             unit_code ? unit_code : ""))
+                : UnitOfMeasure::DEGREE;
+}
+
+// ---------------------------------------------------------------------------
+
+static GeodeticReferenceFrameNNPtr createGeodeticReferenceFrame(
+    PJ_CONTEXT *ctx, const char *datum_name, const char *ellps_name,
+    double semi_major_metre, double inv_flattening,
+    const char *prime_meridian_name, double prime_meridian_offset,
+    const char *angular_units, double angular_units_conv) {
+    const UnitOfMeasure angUnit(
+        createAngularUnit(angular_units, angular_units_conv));
+    auto dbContext = getDBcontextNoException(ctx, __FUNCTION__);
+    auto body = Ellipsoid::guessBodyName(dbContext, semi_major_metre);
+    auto ellpsName = createPropertyMapName(ellps_name);
+    auto ellps = inv_flattening != 0.0
+                     ? Ellipsoid::createFlattenedSphere(
+                           ellpsName, Length(semi_major_metre),
+                           Scale(inv_flattening), body)
+                     : Ellipsoid::createSphere(ellpsName,
+                                               Length(semi_major_metre), body);
+    auto pm = PrimeMeridian::create(
+        PropertyMap().set(
+            common::IdentifiedObject::NAME_KEY,
+            prime_meridian_name
+                ? prime_meridian_name
+                : prime_meridian_offset == 0.0
+                      ? (ellps->celestialBody() == Ellipsoid::EARTH
+                             ? PrimeMeridian::GREENWICH->nameStr().c_str()
+                             : PrimeMeridian::REFERENCE_MERIDIAN->nameStr()
+                                   .c_str())
+                      : "unnamed"),
+        Angle(prime_meridian_offset, angUnit));
+
+    std::string datumName(datum_name ? datum_name : "unnamed");
+    if (datumName == "WGS_1984") {
+        datumName = GeodeticReferenceFrame::EPSG_6326->nameStr();
+    } else if (datumName.find('_') != std::string::npos) {
+        // Likely coming from WKT1
+        if (dbContext) {
+            auto authFactory =
+                AuthorityFactory::create(NN_NO_CHECK(dbContext), std::string());
+            auto res = authFactory->createObjectsFromName(
+                datumName,
+                {AuthorityFactory::ObjectType::GEODETIC_REFERENCE_FRAME}, true,
+                1);
+            if (!res.empty()) {
+                const auto &refDatum = res.front();
+                if (metadata::Identifier::isEquivalentName(
+                        datumName.c_str(), refDatum->nameStr().c_str())) {
+                    datumName = refDatum->nameStr();
+                }
+            } else {
+                std::string outTableName;
+                std::string authNameFromAlias;
+                std::string codeFromAlias;
+                auto officialName = authFactory->getOfficialNameFromAlias(
+                    datumName, "geodetic_datum", std::string(), true,
+                    outTableName, authNameFromAlias, codeFromAlias);
+                if (!officialName.empty()) {
+                    datumName = officialName;
+                }
+            }
+        }
+    }
+
+    return GeodeticReferenceFrame::create(
+        createPropertyMapName(datumName.c_str()), ellps,
+        util::optional<std::string>(), pm);
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Create a GeographicCRS.
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after
+ * use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param crs_name Name of the GeographicCRS. Or NULL
+ * @param datum_name Name of the GeodeticReferenceFrame. Or NULL
+ * @param ellps_name Name of the Ellipsoid. Or NULL
+ * @param semi_major_metre Ellipsoid semi-major axis, in metres.
+ * @param inv_flattening Ellipsoid inverse flattening. Or 0 for a sphere.
+ * @param prime_meridian_name Name of the PrimeMeridian. Or NULL
+ * @param prime_meridian_offset Offset of the prime meridian, expressed in the
+ * specified angular units.
+ * @param pm_angular_units Name of the angular units. Or NULL for Degree
+ * @param pm_angular_units_conv Conversion factor from the angular unit to
+ * radian.
+ * Or
+ * 0 for Degree if pm_angular_units == NULL. Otherwise should be not NULL
+ * @param ellipsoidal_cs Coordinate system. Must not be NULL.
+ *
+ * @return Object of type GeographicCRS that must be unreferenced with
+ * proj_obj_destroy(), or NULL in case of error.
+ */
+PJ_OBJ *proj_obj_create_geographic_crs(
+    PJ_CONTEXT *ctx, const char *crs_name, const char *datum_name,
+    const char *ellps_name, double semi_major_metre, double inv_flattening,
+    const char *prime_meridian_name, double prime_meridian_offset,
+    const char *pm_angular_units, double pm_angular_units_conv,
+    PJ_OBJ *ellipsoidal_cs) {
+
+    SANITIZE_CTX(ctx);
+    auto cs = util::nn_dynamic_pointer_cast<EllipsoidalCS>(ellipsoidal_cs->obj);
+    if (!cs) {
+        return nullptr;
+    }
+    try {
+        auto datum = createGeodeticReferenceFrame(
+            ctx, datum_name, ellps_name, semi_major_metre, inv_flattening,
+            prime_meridian_name, prime_meridian_offset, pm_angular_units,
+            pm_angular_units_conv);
+        auto geogCRS = GeographicCRS::create(createPropertyMapName(crs_name),
+                                             datum, NN_NO_CHECK(cs));
+        return PJ_OBJ::create(geogCRS);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Create a GeographicCRS.
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after
+ * use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param crs_name Name of the GeographicCRS. Or NULL
+ * @param datum Datum. Must not be NULL.
+ * @param ellipsoidal_cs Coordinate system. Must not be NULL.
+ *
+ * @return Object of type GeographicCRS that must be unreferenced with
+ * proj_obj_destroy(), or NULL in case of error.
+ */
+PJ_OBJ *proj_obj_create_geographic_crs_from_datum(PJ_CONTEXT *ctx,
+                                                  const char *crs_name,
+                                                  PJ_OBJ *datum,
+                                                  PJ_OBJ *ellipsoidal_cs) {
+
+    SANITIZE_CTX(ctx);
+    auto l_datum =
+        util::nn_dynamic_pointer_cast<GeodeticReferenceFrame>(datum->obj);
+    if (!l_datum) {
+        proj_log_error(ctx, __FUNCTION__,
+                       "datum is not a GeodeticReferenceFrame");
+        return nullptr;
+    }
+    auto cs = util::nn_dynamic_pointer_cast<EllipsoidalCS>(ellipsoidal_cs->obj);
+    if (!cs) {
+        return nullptr;
+    }
+    try {
+        auto geogCRS =
+            GeographicCRS::create(createPropertyMapName(crs_name),
+                                  NN_NO_CHECK(l_datum), NN_NO_CHECK(cs));
+        return PJ_OBJ::create(geogCRS);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Create a GeodeticCRS of geocentric type.
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after
+ * use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param crs_name Name of the GeographicCRS. Or NULL
+ * @param datum_name Name of the GeodeticReferenceFrame. Or NULL
+ * @param ellps_name Name of the Ellipsoid. Or NULL
+ * @param semi_major_metre Ellipsoid semi-major axis, in metres.
+ * @param inv_flattening Ellipsoid inverse flattening. Or 0 for a sphere.
+ * @param prime_meridian_name Name of the PrimeMeridian. Or NULL
+ * @param prime_meridian_offset Offset of the prime meridian, expressed in the
+ * specified angular units.
+ * @param angular_units Name of the angular units. Or NULL for Degree
+ * @param angular_units_conv Conversion factor from the angular unit to radian.
+ * Or
+ * 0 for Degree if angular_units == NULL. Otherwise should be not NULL
+ * @param linear_units Name of the linear units. Or NULL for Metre
+ * @param linear_units_conv Conversion factor from the linear unit to metre. Or
+ * 0 for Metre if linear_units == NULL. Otherwise should be not NULL
+ *
+ * @return Object of type GeodeticCRS that must be unreferenced with
+ * proj_obj_destroy(), or NULL in case of error.
+ */
+PJ_OBJ *proj_obj_create_geocentric_crs(
+    PJ_CONTEXT *ctx, const char *crs_name, const char *datum_name,
+    const char *ellps_name, double semi_major_metre, double inv_flattening,
+    const char *prime_meridian_name, double prime_meridian_offset,
+    const char *angular_units, double angular_units_conv,
+    const char *linear_units, double linear_units_conv) {
+
+    SANITIZE_CTX(ctx);
+    try {
+        const UnitOfMeasure linearUnit(
+            createLinearUnit(linear_units, linear_units_conv));
+        auto datum = createGeodeticReferenceFrame(
+            ctx, datum_name, ellps_name, semi_major_metre, inv_flattening,
+            prime_meridian_name, prime_meridian_offset, angular_units,
+            angular_units_conv);
+
+        auto geodCRS =
+            GeodeticCRS::create(createPropertyMapName(crs_name), datum,
+                                cs::CartesianCS::createGeocentric(linearUnit));
+        return PJ_OBJ::create(geodCRS);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Create a GeodeticCRS of geocentric type.
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after
+ * use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param crs_name Name of the GeographicCRS. Or NULL
+ * @param datum Datum. Must not be NULL.
+ * @param linear_units Name of the linear units. Or NULL for Metre
+ * @param linear_units_conv Conversion factor from the linear unit to metre. Or
+ * 0 for Metre if linear_units == NULL. Otherwise should be not NULL
+ *
+ * @return Object of type GeodeticCRS that must be unreferenced with
+ * proj_obj_destroy(), or NULL in case of error.
+ */
+PJ_OBJ *proj_obj_create_geocentric_crs_from_datum(PJ_CONTEXT *ctx,
+                                                  const char *crs_name,
+                                                  const PJ_OBJ *datum,
+                                                  const char *linear_units,
+                                                  double linear_units_conv) {
+    SANITIZE_CTX(ctx);
+    try {
+        const UnitOfMeasure linearUnit(
+            createLinearUnit(linear_units, linear_units_conv));
+        auto l_datum =
+            util::nn_dynamic_pointer_cast<GeodeticReferenceFrame>(datum->obj);
+        if (!l_datum) {
+            proj_log_error(ctx, __FUNCTION__,
+                           "datum is not a GeodeticReferenceFrame");
+            return nullptr;
+        }
+        auto geodCRS = GeodeticCRS::create(
+            createPropertyMapName(crs_name), NN_NO_CHECK(l_datum),
+            cs::CartesianCS::createGeocentric(linearUnit));
+        return PJ_OBJ::create(geodCRS);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Create a VerticalCRS
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after
+ * use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param crs_name Name of the GeographicCRS. Or NULL
+ * @param datum_name Name of the VerticalReferenceFrame. Or NULL
+ * @param linear_units Name of the linear units. Or NULL for Metre
+ * @param linear_units_conv Conversion factor from the linear unit to metre. Or
+ * 0 for Metre if linear_units == NULL. Otherwise should be not NULL
+ *
+ * @return Object of type VerticalCRS that must be unreferenced with
+ * proj_obj_destroy(), or NULL in case of error.
+ */
+PJ_OBJ *proj_obj_create_vertical_crs(PJ_CONTEXT *ctx, const char *crs_name,
+                                     const char *datum_name,
+                                     const char *linear_units,
+                                     double linear_units_conv) {
+
+    SANITIZE_CTX(ctx);
+    try {
+        const UnitOfMeasure linearUnit(
+            createLinearUnit(linear_units, linear_units_conv));
+        auto datum =
+            VerticalReferenceFrame::create(createPropertyMapName(datum_name));
+        auto vertCRS = VerticalCRS::create(
+            createPropertyMapName(crs_name), datum,
+            cs::VerticalCS::createGravityRelatedHeight(linearUnit));
+        return PJ_OBJ::create(vertCRS);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Create a CompoundCRS
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after
+ * use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param crs_name Name of the GeographicCRS. Or NULL
+ * @param horiz_crs Horizontal CRS. must not be NULL.
+ * @param vert_crs Vertical CRS. must not be NULL.
+ *
+ * @return Object of type CompoundCRS that must be unreferenced with
+ * proj_obj_destroy(), or NULL in case of error.
+ */
+PJ_OBJ *proj_obj_create_compound_crs(PJ_CONTEXT *ctx, const char *crs_name,
+                                     PJ_OBJ *horiz_crs, PJ_OBJ *vert_crs) {
+
+    assert(horiz_crs);
+    assert(vert_crs);
+    SANITIZE_CTX(ctx);
+    auto l_horiz_crs = util::nn_dynamic_pointer_cast<CRS>(horiz_crs->obj);
+    if (!l_horiz_crs) {
+        return nullptr;
+    }
+    auto l_vert_crs = util::nn_dynamic_pointer_cast<CRS>(vert_crs->obj);
+    if (!l_vert_crs) {
+        return nullptr;
+    }
+    try {
+        auto compoundCRS = CompoundCRS::create(
+            createPropertyMapName(crs_name),
+            {NN_NO_CHECK(l_horiz_crs), NN_NO_CHECK(l_vert_crs)});
+        return PJ_OBJ::create(compoundCRS);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return a copy of the object with its name changed
+ *
+ * Currently, only implemented on CRS objects.
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after
+ * use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param obj Object of type CRS. Must not be NULL
+ * @param name New name. Must not be NULL
+ *
+ * @return Object that must be unreferenced with
+ * proj_obj_destroy(), or NULL in case of error.
+ */
+PJ_OBJ PROJ_DLL *proj_obj_alter_name(PJ_CONTEXT *ctx, const PJ_OBJ *obj,
+                                     const char *name) {
+    SANITIZE_CTX(ctx);
+    auto crs = dynamic_cast<const CRS *>(obj->obj.get());
+    if (!crs) {
+        return nullptr;
+    }
+    try {
+        return PJ_OBJ::create(crs->alterName(name));
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return a copy of the object with its identifier changed/set
+ *
+ * Currently, only implemented on CRS objects.
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after
+ * use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param obj Object of type CRS. Must not be NULL
+ * @param auth_name Authority name. Must not be NULL
+ * @param code Code. Must not be NULL
+ *
+ * @return Object that must be unreferenced with
+ * proj_obj_destroy(), or NULL in case of error.
+ */
+PJ_OBJ PROJ_DLL *proj_obj_alter_id(PJ_CONTEXT *ctx, const PJ_OBJ *obj,
+                                   const char *auth_name, const char *code) {
+    SANITIZE_CTX(ctx);
+    auto crs = dynamic_cast<const CRS *>(obj->obj.get());
+    if (!crs) {
+        return nullptr;
+    }
+    try {
+        return PJ_OBJ::create(crs->alterId(auth_name, code));
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return a copy of the CRS with its geodetic CRS changed
+ *
+ * Currently, when obj is a GeodeticCRS, it returns a clone of new_geod_crs
+ * When obj is a ProjectedCRS, it replaces its base CRS with new_geod_crs.
+ * When obj is a CompoundCRS, it replaces the GeodeticCRS part of the horizontal
+ * CRS with new_geod_crs.
+ * In other cases, it returns a clone of obj.
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after
+ * use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param obj Object of type CRS. Must not be NULL
+ * @param new_geod_crs Object of type GeodeticCRS. Must not be NULL
+ *
+ * @return Object that must be unreferenced with
+ * proj_obj_destroy(), or NULL in case of error.
+ */
+PJ_OBJ *proj_obj_crs_alter_geodetic_crs(PJ_CONTEXT *ctx, const PJ_OBJ *obj,
+                                        const PJ_OBJ *new_geod_crs) {
+    SANITIZE_CTX(ctx);
+    auto l_new_geod_crs =
+        util::nn_dynamic_pointer_cast<GeodeticCRS>(new_geod_crs->obj);
+    if (!l_new_geod_crs) {
+        proj_log_error(ctx, __FUNCTION__, "new_geod_crs is not a GeodeticCRS");
+        return nullptr;
+    }
+
+    auto crs = dynamic_cast<const CRS *>(obj->obj.get());
+    if (!crs) {
+        proj_log_error(ctx, __FUNCTION__, "obj is not a CRS");
+        return nullptr;
+    }
+
+    try {
+        return PJ_OBJ::create(
+            crs->alterGeodeticCRS(NN_NO_CHECK(l_new_geod_crs)));
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+        return nullptr;
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return a copy of the CRS with its angular units changed
+ *
+ * The CRS must be or contain a GeographicCRS.
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after
+ * use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param obj Object of type CRS. Must not be NULL
+ * @param angular_units Name of the angular units. Or NULL for Degree
+ * @param angular_units_conv Conversion factor from the angular unit to radian.
+ * Or 0 for Degree if angular_units == NULL. Otherwise should be not NULL
+ * @param unit_auth_name Unit authority name. Or NULL.
+ * @param unit_code Unit code. Or NULL.
+ *
+ * @return Object that must be unreferenced with
+ * proj_obj_destroy(), or NULL in case of error.
+ */
+PJ_OBJ *proj_obj_crs_alter_cs_angular_unit(PJ_CONTEXT *ctx, const PJ_OBJ *obj,
+                                           const char *angular_units,
+                                           double angular_units_conv,
+                                           const char *unit_auth_name,
+                                           const char *unit_code) {
+
+    SANITIZE_CTX(ctx);
+    auto geodCRS = proj_obj_crs_get_geodetic_crs(ctx, obj);
+    if (!geodCRS) {
+        return nullptr;
+    }
+    auto geogCRS = dynamic_cast<const GeographicCRS *>(geodCRS->obj.get());
+    if (!geogCRS) {
+        proj_obj_destroy(geodCRS);
+        return nullptr;
+    }
+
+    PJ_OBJ *geogCRSAltered = nullptr;
+    try {
+        const UnitOfMeasure angUnit(createAngularUnit(
+            angular_units, angular_units_conv, unit_auth_name, unit_code));
+        geogCRSAltered = PJ_OBJ::create(GeographicCRS::create(
+            createPropertyMapName(proj_obj_get_name(geodCRS)), geogCRS->datum(),
+            geogCRS->datumEnsemble(),
+            geogCRS->coordinateSystem()->alterAngularUnit(angUnit)));
+        proj_obj_destroy(geodCRS);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+        proj_obj_destroy(geodCRS);
+        return nullptr;
+    }
+
+    auto ret = proj_obj_crs_alter_geodetic_crs(ctx, obj, geogCRSAltered);
+    proj_obj_destroy(geogCRSAltered);
+    return ret;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return a copy of the CRS with the linear units of its coordinate
+ * system changed
+ *
+ * The CRS must be or contain a ProjectedCRS, VerticalCRS or a GeocentricCRS.
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after
+ * use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param obj Object of type CRS. Must not be NULL
+ * @param linear_units Name of the linear units. Or NULL for Metre
+ * @param linear_units_conv Conversion factor from the linear unit to metre. Or
+ * 0 for Metre if linear_units == NULL. Otherwise should be not NULL
+ * @param unit_auth_name Unit authority name. Or NULL.
+ * @param unit_code Unit code. Or NULL.
+ *
+ * @return Object that must be unreferenced with
+ * proj_obj_destroy(), or NULL in case of error.
+ */
+PJ_OBJ *proj_obj_crs_alter_cs_linear_unit(PJ_CONTEXT *ctx, const PJ_OBJ *obj,
+                                          const char *linear_units,
+                                          double linear_units_conv,
+                                          const char *unit_auth_name,
+                                          const char *unit_code) {
+    SANITIZE_CTX(ctx);
+    auto crs = dynamic_cast<const CRS *>(obj->obj.get());
+    if (!crs) {
+        return nullptr;
+    }
+
+    try {
+        const UnitOfMeasure linearUnit(createLinearUnit(
+            linear_units, linear_units_conv, unit_auth_name, unit_code));
+        return PJ_OBJ::create(crs->alterCSLinearUnit(linearUnit));
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+        return nullptr;
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return a copy of the CRS with the lineaer units of the parameters
+ * of its conversion modified.
+ *
+ * The CRS must be or contain a ProjectedCRS, VerticalCRS or a GeocentricCRS.
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after
+ * use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param obj Object of type ProjectedCRS. Must not be NULL
+ * @param linear_units Name of the linear units. Or NULL for Metre
+ * @param linear_units_conv Conversion factor from the linear unit to metre. Or
+ * 0 for Metre if linear_units == NULL. Otherwise should be not NULL
+ * @param unit_auth_name Unit authority name. Or NULL.
+ * @param unit_code Unit code. Or NULL.
+ * @param convert_to_new_unit TRUE if exisiting values should be converted from
+ * their current unit to the new unit. If FALSE, their value will be left
+ * unchanged and the unit overriden (so the resulting CRS will not be
+ * equivalent to the original one for reprojection purposes).
+ *
+ * @return Object that must be unreferenced with
+ * proj_obj_destroy(), or NULL in case of error.
+ */
+PJ_OBJ *proj_obj_crs_alter_parameters_linear_unit(
+    PJ_CONTEXT *ctx, const PJ_OBJ *obj, const char *linear_units,
+    double linear_units_conv, const char *unit_auth_name, const char *unit_code,
+    int convert_to_new_unit) {
+    SANITIZE_CTX(ctx);
+    auto crs = dynamic_cast<const ProjectedCRS *>(obj->obj.get());
+    if (!crs) {
+        return nullptr;
+    }
+
+    try {
+        const UnitOfMeasure linearUnit(createLinearUnit(
+            linear_units, linear_units_conv, unit_auth_name, unit_code));
+        return PJ_OBJ::create(crs->alterParametersLinearUnit(
+            linearUnit, convert_to_new_unit == TRUE));
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+        return nullptr;
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a EngineeringCRS with just a name
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after
+ * use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param crs_name CRS name. Or NULL.
+ *
+ * @return Object that must be unreferenced with
+ * proj_obj_destroy(), or NULL in case of error.
+ */
+PJ_OBJ PROJ_DLL *proj_obj_create_engineering_crs(PJ_CONTEXT *ctx,
+                                                 const char *crs_name) {
+    SANITIZE_CTX(ctx);
+    try {
+        return PJ_OBJ::create(EngineeringCRS::create(
+            createPropertyMapName(crs_name),
+            EngineeringDatum::create(PropertyMap()),
+            CartesianCS::createEastingNorthing(UnitOfMeasure::METRE)));
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+        return nullptr;
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+static void setSingleOperationElements(
+    const char *name, const char *auth_name, const char *code,
+    const char *method_name, const char *method_auth_name,
+    const char *method_code, int param_count,
+    const PJ_PARAM_DESCRIPTION *params, PropertyMap &propSingleOp,
+    PropertyMap &propMethod, std::vector<OperationParameterNNPtr> &parameters,
+    std::vector<ParameterValueNNPtr> &values) {
+    propSingleOp.set(common::IdentifiedObject::NAME_KEY,
+                     name ? name : "unnamed");
+    if (auth_name && code) {
+        propSingleOp.set(metadata::Identifier::CODESPACE_KEY, auth_name)
+            .set(metadata::Identifier::CODE_KEY, code);
+    }
+
+    propMethod.set(common::IdentifiedObject::NAME_KEY,
+                   method_name ? method_name : "unnamed");
+    if (method_auth_name && method_code) {
+        propMethod.set(metadata::Identifier::CODESPACE_KEY, method_auth_name)
+            .set(metadata::Identifier::CODE_KEY, method_code);
+    }
+
+    for (int i = 0; i < param_count; i++) {
+        PropertyMap propParam;
+        propParam.set(common::IdentifiedObject::NAME_KEY,
+                      params[i].name ? params[i].name : "unnamed");
+        if (params[i].auth_name && params[i].code) {
+            propParam
+                .set(metadata::Identifier::CODESPACE_KEY, params[i].auth_name)
+                .set(metadata::Identifier::CODE_KEY, params[i].code);
+        }
+        parameters.emplace_back(OperationParameter::create(propParam));
+        auto unit_type = UnitOfMeasure::Type::UNKNOWN;
+        switch (params[i].unit_type) {
+        case PJ_UT_ANGULAR:
+            unit_type = UnitOfMeasure::Type::ANGULAR;
+            break;
+        case PJ_UT_LINEAR:
+            unit_type = UnitOfMeasure::Type::LINEAR;
+            break;
+        case PJ_UT_SCALE:
+            unit_type = UnitOfMeasure::Type::SCALE;
+            break;
+        case PJ_UT_TIME:
+            unit_type = UnitOfMeasure::Type::TIME;
+            break;
+        case PJ_UT_PARAMETRIC:
+            unit_type = UnitOfMeasure::Type::PARAMETRIC;
+            break;
+        }
+
+        Measure measure(
+            params[i].value,
+            params[i].unit_type == PJ_UT_ANGULAR
+                ? createAngularUnit(params[i].unit_name,
+                                    params[i].unit_conv_factor)
+                : params[i].unit_type == PJ_UT_LINEAR
+                      ? createLinearUnit(params[i].unit_name,
+                                         params[i].unit_conv_factor)
+                      : UnitOfMeasure(params[i].unit_name ? params[i].unit_name
+                                                          : "unnamed",
+                                      params[i].unit_conv_factor, unit_type));
+        values.emplace_back(ParameterValue::create(measure));
+    }
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a Conversion
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after
+ * use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param name Conversion name. Or NULL.
+ * @param auth_name Conversion authority name. Or NULL.
+ * @param code Conversion code. Or NULL.
+ * @param method_name Method name. Or NULL.
+ * @param method_auth_name Method authority name. Or NULL.
+ * @param method_code Method code. Or NULL.
+ * @param param_count Number of parameters (size of params argument)
+ * @param params Parameter descriptions (array of size param_count)
+ *
+ * @return Object that must be unreferenced with
+ * proj_obj_destroy(), or NULL in case of error.
+ */
+
+PJ_OBJ *proj_obj_create_conversion(PJ_CONTEXT *ctx, const char *name,
+                                   const char *auth_name, const char *code,
+                                   const char *method_name,
+                                   const char *method_auth_name,
+                                   const char *method_code, int param_count,
+                                   const PJ_PARAM_DESCRIPTION *params) {
+    SANITIZE_CTX(ctx);
+    try {
+        PropertyMap propSingleOp;
+        PropertyMap propMethod;
+        std::vector<OperationParameterNNPtr> parameters;
+        std::vector<ParameterValueNNPtr> values;
+
+        setSingleOperationElements(
+            name, auth_name, code, method_name, method_auth_name, method_code,
+            param_count, params, propSingleOp, propMethod, parameters, values);
+
+        return PJ_OBJ::create(
+            Conversion::create(propSingleOp, propMethod, parameters, values));
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+        return nullptr;
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a Transformation
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after
+ * use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param name Transformation name. Or NULL.
+ * @param auth_name Transformation authority name. Or NULL.
+ * @param code Transformation code. Or NULL.
+ * @param source_crs Object of type CRS representing the source CRS.
+ * Must not be NULL.
+ * @param target_crs Object of type CRS representing the target CRS.
+ * Must not be NULL.
+ * @param interpolation_crs Object of type CRS representing the interpolation
+ * CRS. Or NULL.
+ * @param method_name Method name. Or NULL.
+ * @param method_auth_name Method authority name. Or NULL.
+ * @param method_code Method code. Or NULL.
+ * @param param_count Number of parameters (size of params argument)
+ * @param params Parameter descriptions (array of size param_count)
+ * @param accuracy Accuracy of the transformation in meters. A negative
+ * values means unknown.
+ *
+ * @return Object that must be unreferenced with
+ * proj_obj_destroy(), or NULL in case of error.
+ */
+
+PJ_OBJ *proj_obj_create_transformation(
+    PJ_CONTEXT *ctx, const char *name, const char *auth_name, const char *code,
+    PJ_OBJ *source_crs, PJ_OBJ *target_crs, PJ_OBJ *interpolation_crs,
+    const char *method_name, const char *method_auth_name,
+    const char *method_code, int param_count,
+    const PJ_PARAM_DESCRIPTION *params, double accuracy) {
+    SANITIZE_CTX(ctx);
+    assert(source_crs);
+    assert(target_crs);
+
+    auto l_sourceCRS = util::nn_dynamic_pointer_cast<CRS>(source_crs->obj);
+    if (!l_sourceCRS) {
+        proj_log_error(ctx, __FUNCTION__, "source_crs is not a CRS");
+        return nullptr;
+    }
+
+    auto l_targetCRS = util::nn_dynamic_pointer_cast<CRS>(target_crs->obj);
+    if (!l_targetCRS) {
+        proj_log_error(ctx, __FUNCTION__, "target_crs is not a CRS");
+        return nullptr;
+    }
+
+    CRSPtr l_interpolationCRS;
+    if (interpolation_crs) {
+        l_interpolationCRS =
+            util::nn_dynamic_pointer_cast<CRS>(interpolation_crs->obj);
+        if (!l_interpolationCRS) {
+            proj_log_error(ctx, __FUNCTION__, "interpolation_crs is not a CRS");
+            return nullptr;
+        }
+    }
+
+    try {
+        PropertyMap propSingleOp;
+        PropertyMap propMethod;
+        std::vector<OperationParameterNNPtr> parameters;
+        std::vector<ParameterValueNNPtr> values;
+
+        setSingleOperationElements(
+            name, auth_name, code, method_name, method_auth_name, method_code,
+            param_count, params, propSingleOp, propMethod, parameters, values);
+
+        std::vector<metadata::PositionalAccuracyNNPtr> accuracies;
+        if (accuracy >= 0.0) {
+            accuracies.emplace_back(
+                PositionalAccuracy::create(toString(accuracy)));
+        }
+
+        return PJ_OBJ::create(Transformation::create(
+            propSingleOp, NN_NO_CHECK(l_sourceCRS), NN_NO_CHECK(l_targetCRS),
+            l_interpolationCRS, propMethod, parameters, values, accuracies));
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+        return nullptr;
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/**
+ * \brief Return an equivalent projection.
+ *
+ * Currently implemented:
+ * <ul>
+ * <li>EPSG_CODE_METHOD_MERCATOR_VARIANT_A (1SP) to
+ * EPSG_CODE_METHOD_MERCATOR_VARIANT_B (2SP)</li>
+ * <li>EPSG_CODE_METHOD_MERCATOR_VARIANT_B (2SP) to
+ * EPSG_CODE_METHOD_MERCATOR_VARIANT_A (1SP)</li>
+ * <li>EPSG_CODE_METHOD_LAMBERT_CONIC_CONFORMAL_1SP to
+ * EPSG_CODE_METHOD_LAMBERT_CONIC_CONFORMAL_2SP</li>
+ * <li>EPSG_CODE_METHOD_LAMBERT_CONIC_CONFORMAL_2SP to
+ * EPSG_CODE_METHOD_LAMBERT_CONIC_CONFORMAL_1SP</li>
+ * </ul>
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param conversion Object of type Conversion. Must not be NULL.
+ * @param new_method_epsg_code EPSG code of the target method. Or 0 (in which
+ * case new_method_name must be specified).
+ * @param new_method_name EPSG or PROJ target method name. Or nullptr  (in which
+ * case new_method_epsg_code must be specified).
+ * @return new conversion that must be unreferenced with
+ * proj_obj_destroy(), or NULL in case of error.
+ */
+PJ_OBJ *proj_obj_convert_conversion_to_other_method(
+    PJ_CONTEXT *ctx, const PJ_OBJ *conversion, int new_method_epsg_code,
+    const char *new_method_name) {
+    SANITIZE_CTX(ctx);
+    auto conv = dynamic_cast<const Conversion *>(conversion->obj.get());
+    if (!conv) {
+        proj_log_error(ctx, __FUNCTION__, "not a Conversion");
+        return nullptr;
+    }
+    if (new_method_epsg_code == 0) {
+        if (!new_method_name) {
+            return nullptr;
+        }
+        if (metadata::Identifier::isEquivalentName(
+                new_method_name, EPSG_NAME_METHOD_MERCATOR_VARIANT_A)) {
+            new_method_epsg_code = EPSG_CODE_METHOD_MERCATOR_VARIANT_A;
+        } else if (metadata::Identifier::isEquivalentName(
+                       new_method_name, EPSG_NAME_METHOD_MERCATOR_VARIANT_B)) {
+            new_method_epsg_code = EPSG_CODE_METHOD_MERCATOR_VARIANT_B;
+        } else if (metadata::Identifier::isEquivalentName(
+                       new_method_name,
+                       EPSG_NAME_METHOD_LAMBERT_CONIC_CONFORMAL_1SP)) {
+            new_method_epsg_code = EPSG_CODE_METHOD_LAMBERT_CONIC_CONFORMAL_1SP;
+        } else if (metadata::Identifier::isEquivalentName(
+                       new_method_name,
+                       EPSG_NAME_METHOD_LAMBERT_CONIC_CONFORMAL_2SP)) {
+            new_method_epsg_code = EPSG_CODE_METHOD_LAMBERT_CONIC_CONFORMAL_2SP;
+        }
+    }
+    try {
+        auto new_conv = conv->convertToOtherMethod(new_method_epsg_code);
+        if (!new_conv)
+            return nullptr;
+        return PJ_OBJ::create(NN_NO_CHECK(new_conv));
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+        return nullptr;
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+static CoordinateSystemAxisNNPtr createAxis(const PJ_AXIS_DESCRIPTION &axis) {
+    const auto dir =
+        axis.direction ? AxisDirection::valueOf(axis.direction) : nullptr;
+    if (dir == nullptr)
+        throw Exception("invalid value for axis direction");
+    auto unit_type = UnitOfMeasure::Type::UNKNOWN;
+    switch (axis.unit_type) {
+    case PJ_UT_ANGULAR:
+        unit_type = UnitOfMeasure::Type::ANGULAR;
+        break;
+    case PJ_UT_LINEAR:
+        unit_type = UnitOfMeasure::Type::LINEAR;
+        break;
+    case PJ_UT_SCALE:
+        unit_type = UnitOfMeasure::Type::SCALE;
+        break;
+    case PJ_UT_TIME:
+        unit_type = UnitOfMeasure::Type::TIME;
+        break;
+    case PJ_UT_PARAMETRIC:
+        unit_type = UnitOfMeasure::Type::PARAMETRIC;
+        break;
+    }
+    auto unit =
+        axis.unit_type == PJ_UT_ANGULAR
+            ? createAngularUnit(axis.unit_name, axis.unit_conv_factor)
+            : axis.unit_type == PJ_UT_LINEAR
+                  ? createLinearUnit(axis.unit_name, axis.unit_conv_factor)
+                  : UnitOfMeasure(axis.unit_name ? axis.unit_name : "unnamed",
+                                  axis.unit_conv_factor, unit_type);
+
+    return CoordinateSystemAxis::create(
+        createPropertyMapName(axis.name),
+        axis.abbreviation ? axis.abbreviation : std::string(), *dir, unit);
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a CoordinateSystem.
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after
+ * use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param type Coordinate system type.
+ * @param axis_count Number of axis
+ * @param axis Axis description (array of size axis_count)
+ *
+ * @return Object that must be unreferenced with
+ * proj_obj_destroy(), or NULL in case of error.
+ */
+
+PJ_OBJ *proj_obj_create_cs(PJ_CONTEXT *ctx, PJ_COORDINATE_SYSTEM_TYPE type,
+                           int axis_count, const PJ_AXIS_DESCRIPTION *axis) {
+    try {
+        switch (type) {
+        case PJ_CS_TYPE_UNKNOWN:
+            return nullptr;
+
+        case PJ_CS_TYPE_CARTESIAN: {
+            if (axis_count == 2) {
+                return PJ_OBJ::create(CartesianCS::create(
+                    PropertyMap(), createAxis(axis[0]), createAxis(axis[1])));
+            } else if (axis_count == 3) {
+                return PJ_OBJ::create(CartesianCS::create(
+                    PropertyMap(), createAxis(axis[0]), createAxis(axis[1]),
+                    createAxis(axis[2])));
+            }
+            break;
+        }
+
+        case PJ_CS_TYPE_ELLIPSOIDAL: {
+            if (axis_count == 2) {
+                return PJ_OBJ::create(EllipsoidalCS::create(
+                    PropertyMap(), createAxis(axis[0]), createAxis(axis[1])));
+            } else if (axis_count == 3) {
+                return PJ_OBJ::create(EllipsoidalCS::create(
+                    PropertyMap(), createAxis(axis[0]), createAxis(axis[1]),
+                    createAxis(axis[2])));
+            }
+            break;
+        }
+
+        case PJ_CS_TYPE_VERTICAL: {
+            if (axis_count == 1) {
+                return PJ_OBJ::create(
+                    VerticalCS::create(PropertyMap(), createAxis(axis[0])));
+            }
+            break;
+        }
+
+        case PJ_CS_TYPE_SPHERICAL: {
+            if (axis_count == 3) {
+                return PJ_OBJ::create(EllipsoidalCS::create(
+                    PropertyMap(), createAxis(axis[0]), createAxis(axis[1]),
+                    createAxis(axis[2])));
+            }
+            break;
+        }
+
+        case PJ_CS_TYPE_PARAMETRIC: {
+            if (axis_count == 1) {
+                return PJ_OBJ::create(
+                    ParametricCS::create(PropertyMap(), createAxis(axis[0])));
+            }
+            break;
+        }
+
+        case PJ_CS_TYPE_ORDINAL: {
+            std::vector<CoordinateSystemAxisNNPtr> axisVector;
+            for (int i = 0; i < axis_count; i++) {
+                axisVector.emplace_back(createAxis(axis[i]));
+            }
+
+            return PJ_OBJ::create(OrdinalCS::create(PropertyMap(), axisVector));
+        }
+
+        case PJ_CS_TYPE_DATETIMETEMPORAL: {
+            if (axis_count == 1) {
+                return PJ_OBJ::create(DateTimeTemporalCS::create(
+                    PropertyMap(), createAxis(axis[0])));
+            }
+            break;
+        }
+
+        case PJ_CS_TYPE_TEMPORALCOUNT: {
+            if (axis_count == 1) {
+                return PJ_OBJ::create(TemporalCountCS::create(
+                    PropertyMap(), createAxis(axis[0])));
+            }
+            break;
+        }
+
+        case PJ_CS_TYPE_TEMPORALMEASURE: {
+            if (axis_count == 1) {
+                return PJ_OBJ::create(TemporalMeasureCS::create(
+                    PropertyMap(), createAxis(axis[0])));
+            }
+            break;
+        }
+        }
+
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+        return nullptr;
+    }
+    proj_log_error(ctx, __FUNCTION__, "Wrong value for axis_count");
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a CartesiansCS 2D
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after
+ * use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param type Coordinate system type.
+ * @param unit_name Unit name.
+ * @param unit_conv_factor Unit conversion factor to SI.
+ *
+ * @return Object that must be unreferenced with
+ * proj_obj_destroy(), or NULL in case of error.
+ */
+
+PJ_OBJ *proj_obj_create_cartesian_2D_cs(PJ_CONTEXT *ctx,
+                                        PJ_CARTESIAN_CS_2D_TYPE type,
+                                        const char *unit_name,
+                                        double unit_conv_factor) {
+    try {
+        switch (type) {
+        case PJ_CART2D_EASTING_NORTHING:
+            return PJ_OBJ::create(CartesianCS::createEastingNorthing(
+                createLinearUnit(unit_name, unit_conv_factor)));
+
+        case PJ_CART2D_NORTHING_EASTING:
+            return PJ_OBJ::create(CartesianCS::createNorthingEasting(
+                createLinearUnit(unit_name, unit_conv_factor)));
+
+        case PJ_CART2D_NORTH_POLE_EASTING_SOUTH_NORTHING_SOUTH:
+            return PJ_OBJ::create(
+                CartesianCS::createNorthPoleEastingSouthNorthingSouth(
+                    createLinearUnit(unit_name, unit_conv_factor)));
+
+        case PJ_CART2D_SOUTH_POLE_EASTING_NORTH_NORTHING_NORTH:
+            return PJ_OBJ::create(
+                CartesianCS::createSouthPoleEastingNorthNorthingNorth(
+                    createLinearUnit(unit_name, unit_conv_factor)));
+
+        case PJ_CART2D_WESTING_SOUTHING:
+            return PJ_OBJ::create(CartesianCS::createWestingSouthing(
+                createLinearUnit(unit_name, unit_conv_factor)));
+        }
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a Ellipsoidal 2D
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after
+ * use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param type Coordinate system type.
+ * @param unit_name Unit name.
+ * @param unit_conv_factor Unit conversion factor to SI.
+ *
+ * @return Object that must be unreferenced with
+ * proj_obj_destroy(), or NULL in case of error.
+ */
+
+PJ_OBJ *proj_obj_create_ellipsoidal_2D_cs(PJ_CONTEXT *ctx,
+                                          PJ_ELLIPSOIDAL_CS_2D_TYPE type,
+                                          const char *unit_name,
+                                          double unit_conv_factor) {
+    try {
+        switch (type) {
+        case PJ_ELLPS2D_LONGITUDE_LATITUDE:
+            return PJ_OBJ::create(EllipsoidalCS::createLongitudeLatitude(
+                createAngularUnit(unit_name, unit_conv_factor)));
+
+        case PJ_ELLPS2D_LATITUDE_LONGITUDE:
+            return PJ_OBJ::create(EllipsoidalCS::createLatitudeLongitude(
+                createAngularUnit(unit_name, unit_conv_factor)));
+        }
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after
+ * use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param crs_name CRS name. Or NULL
+ * @param geodetic_crs Base GeodeticCRS. Must not be NULL.
+ * @param conversion Conversion. Must not be NULL.
+ * @param coordinate_system Cartesian coordinate system. Must not be NULL.
+ *
+ * @return Object that must be unreferenced with
+ * proj_obj_destroy(), or NULL in case of error.
+ */
+
+PJ_OBJ *proj_obj_create_projected_crs(PJ_CONTEXT *ctx, const char *crs_name,
+                                      const PJ_OBJ *geodetic_crs,
+                                      const PJ_OBJ *conversion,
+                                      const PJ_OBJ *coordinate_system) {
+    SANITIZE_CTX(ctx);
+    auto geodCRS =
+        util::nn_dynamic_pointer_cast<GeodeticCRS>(geodetic_crs->obj);
+    if (!geodCRS) {
+        return nullptr;
+    }
+    auto conv = util::nn_dynamic_pointer_cast<Conversion>(conversion->obj);
+    if (!conv) {
+        return nullptr;
+    }
+    auto cs =
+        util::nn_dynamic_pointer_cast<CartesianCS>(coordinate_system->obj);
+    if (!cs) {
+        return nullptr;
+    }
+    try {
+        return PJ_OBJ::create(ProjectedCRS::create(
+            createPropertyMapName(crs_name), NN_NO_CHECK(geodCRS),
+            NN_NO_CHECK(conv), NN_NO_CHECK(cs)));
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+static PJ_OBJ *proj_obj_create_conversion(const ConversionNNPtr &conv) {
+    return PJ_OBJ::create(conv);
+}
+
+//! @endcond
+
+/* BEGIN: Generated by scripts/create_c_api_projections.py*/
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a Universal Transverse Mercator
+ * conversion.
+ *
+ * See osgeo::proj::operation::Conversion::createUTM().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_utm(PJ_CONTEXT *ctx, int zone, int north) {
+    SANITIZE_CTX(ctx);
+    try {
+        auto conv = Conversion::createUTM(PropertyMap(), zone, north != 0);
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Transverse
+ * Mercator projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createTransverseMercator().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_transverse_mercator(
+    PJ_CONTEXT *ctx, double center_lat, double center_long, double scale,
+    double false_easting, double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createTransverseMercator(
+            PropertyMap(), Angle(center_lat, angUnit),
+            Angle(center_long, angUnit), Scale(scale),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Gauss
+ * Schreiber Transverse Mercator projection method.
+ *
+ * See
+ * osgeo::proj::operation::Conversion::createGaussSchreiberTransverseMercator().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_gauss_schreiber_transverse_mercator(
+    PJ_CONTEXT *ctx, double center_lat, double center_long, double scale,
+    double false_easting, double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createGaussSchreiberTransverseMercator(
+            PropertyMap(), Angle(center_lat, angUnit),
+            Angle(center_long, angUnit), Scale(scale),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Transverse
+ * Mercator South Orientated projection method.
+ *
+ * See
+ * osgeo::proj::operation::Conversion::createTransverseMercatorSouthOriented().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_transverse_mercator_south_oriented(
+    PJ_CONTEXT *ctx, double center_lat, double center_long, double scale,
+    double false_easting, double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createTransverseMercatorSouthOriented(
+            PropertyMap(), Angle(center_lat, angUnit),
+            Angle(center_long, angUnit), Scale(scale),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Two Point
+ * Equidistant projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createTwoPointEquidistant().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_two_point_equidistant(
+    PJ_CONTEXT *ctx, double latitude_first_point, double longitude_first_point,
+    double latitude_second_point, double longitude_secon_point,
+    double false_easting, double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createTwoPointEquidistant(
+            PropertyMap(), Angle(latitude_first_point, angUnit),
+            Angle(longitude_first_point, angUnit),
+            Angle(latitude_second_point, angUnit),
+            Angle(longitude_secon_point, angUnit),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Tunisia
+ * Mapping Grid projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createTunisiaMappingGrid().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_tunisia_mapping_grid(
+    PJ_CONTEXT *ctx, double center_lat, double center_long,
+    double false_easting, double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createTunisiaMappingGrid(
+            PropertyMap(), Angle(center_lat, angUnit),
+            Angle(center_long, angUnit), Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Albers
+ * Conic Equal Area projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createAlbersEqualArea().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_albers_equal_area(
+    PJ_CONTEXT *ctx, double latitude_false_origin,
+    double longitude_false_origin, double latitude_first_parallel,
+    double latitude_second_parallel, double easting_false_origin,
+    double northing_false_origin, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createAlbersEqualArea(
+            PropertyMap(), Angle(latitude_false_origin, angUnit),
+            Angle(longitude_false_origin, angUnit),
+            Angle(latitude_first_parallel, angUnit),
+            Angle(latitude_second_parallel, angUnit),
+            Length(easting_false_origin, linearUnit),
+            Length(northing_false_origin, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Lambert
+ * Conic Conformal 1SP projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createLambertConicConformal_1SP().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_lambert_conic_conformal_1sp(
+    PJ_CONTEXT *ctx, double center_lat, double center_long, double scale,
+    double false_easting, double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createLambertConicConformal_1SP(
+            PropertyMap(), Angle(center_lat, angUnit),
+            Angle(center_long, angUnit), Scale(scale),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Lambert
+ * Conic Conformal (2SP) projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createLambertConicConformal_2SP().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_lambert_conic_conformal_2sp(
+    PJ_CONTEXT *ctx, double latitude_false_origin,
+    double longitude_false_origin, double latitude_first_parallel,
+    double latitude_second_parallel, double easting_false_origin,
+    double northing_false_origin, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createLambertConicConformal_2SP(
+            PropertyMap(), Angle(latitude_false_origin, angUnit),
+            Angle(longitude_false_origin, angUnit),
+            Angle(latitude_first_parallel, angUnit),
+            Angle(latitude_second_parallel, angUnit),
+            Length(easting_false_origin, linearUnit),
+            Length(northing_false_origin, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Lambert
+ * Conic Conformal (2SP Michigan) projection method.
+ *
+ * See
+ * osgeo::proj::operation::Conversion::createLambertConicConformal_2SP_Michigan().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_lambert_conic_conformal_2sp_michigan(
+    PJ_CONTEXT *ctx, double latitude_false_origin,
+    double longitude_false_origin, double latitude_first_parallel,
+    double latitude_second_parallel, double easting_false_origin,
+    double northing_false_origin, double ellipsoid_scaling_factor,
+    const char *ang_unit_name, double ang_unit_conv_factor,
+    const char *linear_unit_name, double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createLambertConicConformal_2SP_Michigan(
+            PropertyMap(), Angle(latitude_false_origin, angUnit),
+            Angle(longitude_false_origin, angUnit),
+            Angle(latitude_first_parallel, angUnit),
+            Angle(latitude_second_parallel, angUnit),
+            Length(easting_false_origin, linearUnit),
+            Length(northing_false_origin, linearUnit),
+            Scale(ellipsoid_scaling_factor));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Lambert
+ * Conic Conformal (2SP Belgium) projection method.
+ *
+ * See
+ * osgeo::proj::operation::Conversion::createLambertConicConformal_2SP_Belgium().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_lambert_conic_conformal_2sp_belgium(
+    PJ_CONTEXT *ctx, double latitude_false_origin,
+    double longitude_false_origin, double latitude_first_parallel,
+    double latitude_second_parallel, double easting_false_origin,
+    double northing_false_origin, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createLambertConicConformal_2SP_Belgium(
+            PropertyMap(), Angle(latitude_false_origin, angUnit),
+            Angle(longitude_false_origin, angUnit),
+            Angle(latitude_first_parallel, angUnit),
+            Angle(latitude_second_parallel, angUnit),
+            Length(easting_false_origin, linearUnit),
+            Length(northing_false_origin, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Modified
+ * Azimuthal Equidistant projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createAzimuthalEquidistant().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_azimuthal_equidistant(
+    PJ_CONTEXT *ctx, double latitude_nat_origin, double longitude_nat_origin,
+    double false_easting, double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createAzimuthalEquidistant(
+            PropertyMap(), Angle(latitude_nat_origin, angUnit),
+            Angle(longitude_nat_origin, angUnit),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Guam
+ * Projection projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createGuamProjection().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_guam_projection(
+    PJ_CONTEXT *ctx, double latitude_nat_origin, double longitude_nat_origin,
+    double false_easting, double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createGuamProjection(
+            PropertyMap(), Angle(latitude_nat_origin, angUnit),
+            Angle(longitude_nat_origin, angUnit),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Bonne
+ * projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createBonne().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_bonne(
+    PJ_CONTEXT *ctx, double latitude_nat_origin, double longitude_nat_origin,
+    double false_easting, double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createBonne(
+            PropertyMap(), Angle(latitude_nat_origin, angUnit),
+            Angle(longitude_nat_origin, angUnit),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Lambert
+ * Cylindrical Equal Area (Spherical) projection method.
+ *
+ * See
+ * osgeo::proj::operation::Conversion::createLambertCylindricalEqualAreaSpherical().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_lambert_cylindrical_equal_area_spherical(
+    PJ_CONTEXT *ctx, double latitude_first_parallel,
+    double longitude_nat_origin, double false_easting, double false_northing,
+    const char *ang_unit_name, double ang_unit_conv_factor,
+    const char *linear_unit_name, double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createLambertCylindricalEqualAreaSpherical(
+            PropertyMap(), Angle(latitude_first_parallel, angUnit),
+            Angle(longitude_nat_origin, angUnit),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Lambert
+ * Cylindrical Equal Area (ellipsoidal form) projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createLambertCylindricalEqualArea().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_lambert_cylindrical_equal_area(
+    PJ_CONTEXT *ctx, double latitude_first_parallel,
+    double longitude_nat_origin, double false_easting, double false_northing,
+    const char *ang_unit_name, double ang_unit_conv_factor,
+    const char *linear_unit_name, double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createLambertCylindricalEqualArea(
+            PropertyMap(), Angle(latitude_first_parallel, angUnit),
+            Angle(longitude_nat_origin, angUnit),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the
+ * Cassini-Soldner projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createCassiniSoldner().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_cassini_soldner(
+    PJ_CONTEXT *ctx, double center_lat, double center_long,
+    double false_easting, double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createCassiniSoldner(
+            PropertyMap(), Angle(center_lat, angUnit),
+            Angle(center_long, angUnit), Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Equidistant
+ * Conic projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createEquidistantConic().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_equidistant_conic(
+    PJ_CONTEXT *ctx, double center_lat, double center_long,
+    double latitude_first_parallel, double latitude_second_parallel,
+    double false_easting, double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createEquidistantConic(
+            PropertyMap(), Angle(center_lat, angUnit),
+            Angle(center_long, angUnit),
+            Angle(latitude_first_parallel, angUnit),
+            Angle(latitude_second_parallel, angUnit),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Eckert I
+ * projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createEckertI().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_eckert_i(PJ_CONTEXT *ctx, double center_long,
+                                            double false_easting,
+                                            double false_northing,
+                                            const char *ang_unit_name,
+                                            double ang_unit_conv_factor,
+                                            const char *linear_unit_name,
+                                            double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createEckertI(
+            PropertyMap(), Angle(center_long, angUnit),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Eckert II
+ * projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createEckertII().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_eckert_ii(
+    PJ_CONTEXT *ctx, double center_long, double false_easting,
+    double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createEckertII(
+            PropertyMap(), Angle(center_long, angUnit),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Eckert III
+ * projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createEckertIII().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_eckert_iii(
+    PJ_CONTEXT *ctx, double center_long, double false_easting,
+    double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createEckertIII(
+            PropertyMap(), Angle(center_long, angUnit),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Eckert IV
+ * projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createEckertIV().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_eckert_iv(
+    PJ_CONTEXT *ctx, double center_long, double false_easting,
+    double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createEckertIV(
+            PropertyMap(), Angle(center_long, angUnit),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Eckert V
+ * projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createEckertV().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_eckert_v(PJ_CONTEXT *ctx, double center_long,
+                                            double false_easting,
+                                            double false_northing,
+                                            const char *ang_unit_name,
+                                            double ang_unit_conv_factor,
+                                            const char *linear_unit_name,
+                                            double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createEckertV(
+            PropertyMap(), Angle(center_long, angUnit),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Eckert VI
+ * projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createEckertVI().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_eckert_vi(
+    PJ_CONTEXT *ctx, double center_long, double false_easting,
+    double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createEckertVI(
+            PropertyMap(), Angle(center_long, angUnit),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Equidistant
+ * Cylindrical projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createEquidistantCylindrical().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_equidistant_cylindrical(
+    PJ_CONTEXT *ctx, double latitude_first_parallel,
+    double longitude_nat_origin, double false_easting, double false_northing,
+    const char *ang_unit_name, double ang_unit_conv_factor,
+    const char *linear_unit_name, double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createEquidistantCylindrical(
+            PropertyMap(), Angle(latitude_first_parallel, angUnit),
+            Angle(longitude_nat_origin, angUnit),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Equidistant
+ * Cylindrical (Spherical) projection method.
+ *
+ * See
+ * osgeo::proj::operation::Conversion::createEquidistantCylindricalSpherical().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_equidistant_cylindrical_spherical(
+    PJ_CONTEXT *ctx, double latitude_first_parallel,
+    double longitude_nat_origin, double false_easting, double false_northing,
+    const char *ang_unit_name, double ang_unit_conv_factor,
+    const char *linear_unit_name, double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createEquidistantCylindricalSpherical(
+            PropertyMap(), Angle(latitude_first_parallel, angUnit),
+            Angle(longitude_nat_origin, angUnit),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Gall
+ * (Stereographic) projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createGall().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_gall(PJ_CONTEXT *ctx, double center_long,
+                                        double false_easting,
+                                        double false_northing,
+                                        const char *ang_unit_name,
+                                        double ang_unit_conv_factor,
+                                        const char *linear_unit_name,
+                                        double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv =
+            Conversion::createGall(PropertyMap(), Angle(center_long, angUnit),
+                                   Length(false_easting, linearUnit),
+                                   Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Goode
+ * Homolosine projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createGoodeHomolosine().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_goode_homolosine(
+    PJ_CONTEXT *ctx, double center_long, double false_easting,
+    double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createGoodeHomolosine(
+            PropertyMap(), Angle(center_long, angUnit),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Interrupted
+ * Goode Homolosine projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createInterruptedGoodeHomolosine().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_interrupted_goode_homolosine(
+    PJ_CONTEXT *ctx, double center_long, double false_easting,
+    double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createInterruptedGoodeHomolosine(
+            PropertyMap(), Angle(center_long, angUnit),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the
+ * Geostationary Satellite View projection method, with the sweep angle axis of
+ * the viewing instrument being x.
+ *
+ * See osgeo::proj::operation::Conversion::createGeostationarySatelliteSweepX().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_geostationary_satellite_sweep_x(
+    PJ_CONTEXT *ctx, double center_long, double height, double false_easting,
+    double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createGeostationarySatelliteSweepX(
+            PropertyMap(), Angle(center_long, angUnit),
+            Length(height, linearUnit), Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the
+ * Geostationary Satellite View projection method, with the sweep angle axis of
+ * the viewing instrument being y.
+ *
+ * See osgeo::proj::operation::Conversion::createGeostationarySatelliteSweepY().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_geostationary_satellite_sweep_y(
+    PJ_CONTEXT *ctx, double center_long, double height, double false_easting,
+    double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createGeostationarySatelliteSweepY(
+            PropertyMap(), Angle(center_long, angUnit),
+            Length(height, linearUnit), Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Gnomonic
+ * projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createGnomonic().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_gnomonic(
+    PJ_CONTEXT *ctx, double center_lat, double center_long,
+    double false_easting, double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createGnomonic(
+            PropertyMap(), Angle(center_lat, angUnit),
+            Angle(center_long, angUnit), Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Hotine
+ * Oblique Mercator (Variant A) projection method.
+ *
+ * See
+ * osgeo::proj::operation::Conversion::createHotineObliqueMercatorVariantA().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_hotine_oblique_mercator_variant_a(
+    PJ_CONTEXT *ctx, double latitude_projection_centre,
+    double longitude_projection_centre, double azimuth_initial_line,
+    double angle_from_rectified_to_skrew_grid, double scale,
+    double false_easting, double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createHotineObliqueMercatorVariantA(
+            PropertyMap(), Angle(latitude_projection_centre, angUnit),
+            Angle(longitude_projection_centre, angUnit),
+            Angle(azimuth_initial_line, angUnit),
+            Angle(angle_from_rectified_to_skrew_grid, angUnit), Scale(scale),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Hotine
+ * Oblique Mercator (Variant B) projection method.
+ *
+ * See
+ * osgeo::proj::operation::Conversion::createHotineObliqueMercatorVariantB().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_hotine_oblique_mercator_variant_b(
+    PJ_CONTEXT *ctx, double latitude_projection_centre,
+    double longitude_projection_centre, double azimuth_initial_line,
+    double angle_from_rectified_to_skrew_grid, double scale,
+    double easting_projection_centre, double northing_projection_centre,
+    const char *ang_unit_name, double ang_unit_conv_factor,
+    const char *linear_unit_name, double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createHotineObliqueMercatorVariantB(
+            PropertyMap(), Angle(latitude_projection_centre, angUnit),
+            Angle(longitude_projection_centre, angUnit),
+            Angle(azimuth_initial_line, angUnit),
+            Angle(angle_from_rectified_to_skrew_grid, angUnit), Scale(scale),
+            Length(easting_projection_centre, linearUnit),
+            Length(northing_projection_centre, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Hotine
+ * Oblique Mercator Two Point Natural Origin projection method.
+ *
+ * See
+ * osgeo::proj::operation::Conversion::createHotineObliqueMercatorTwoPointNaturalOrigin().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *
+proj_obj_create_conversion_hotine_oblique_mercator_two_point_natural_origin(
+    PJ_CONTEXT *ctx, double latitude_projection_centre, double latitude_point1,
+    double longitude_point1, double latitude_point2, double longitude_point2,
+    double scale, double easting_projection_centre,
+    double northing_projection_centre, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv =
+            Conversion::createHotineObliqueMercatorTwoPointNaturalOrigin(
+                PropertyMap(), Angle(latitude_projection_centre, angUnit),
+                Angle(latitude_point1, angUnit),
+                Angle(longitude_point1, angUnit),
+                Angle(latitude_point2, angUnit),
+                Angle(longitude_point2, angUnit), Scale(scale),
+                Length(easting_projection_centre, linearUnit),
+                Length(northing_projection_centre, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Laborde
+ * Oblique Mercator projection method.
+ *
+ * See
+ * osgeo::proj::operation::Conversion::createLabordeObliqueMercator().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_laborde_oblique_mercator(
+    PJ_CONTEXT *ctx, double latitude_projection_centre,
+    double longitude_projection_centre, double azimuth_initial_line,
+    double scale, double false_easting, double false_northing,
+    const char *ang_unit_name, double ang_unit_conv_factor,
+    const char *linear_unit_name, double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createLabordeObliqueMercator(
+            PropertyMap(), Angle(latitude_projection_centre, angUnit),
+            Angle(longitude_projection_centre, angUnit),
+            Angle(azimuth_initial_line, angUnit), Scale(scale),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the
+ * International Map of the World Polyconic projection method.
+ *
+ * See
+ * osgeo::proj::operation::Conversion::createInternationalMapWorldPolyconic().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_international_map_world_polyconic(
+    PJ_CONTEXT *ctx, double center_long, double latitude_first_parallel,
+    double latitude_second_parallel, double false_easting,
+    double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createInternationalMapWorldPolyconic(
+            PropertyMap(), Angle(center_long, angUnit),
+            Angle(latitude_first_parallel, angUnit),
+            Angle(latitude_second_parallel, angUnit),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Krovak
+ * (north oriented) projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createKrovakNorthOriented().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_krovak_north_oriented(
+    PJ_CONTEXT *ctx, double latitude_projection_centre,
+    double longitude_of_origin, double colatitude_cone_axis,
+    double latitude_pseudo_standard_parallel,
+    double scale_factor_pseudo_standard_parallel, double false_easting,
+    double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createKrovakNorthOriented(
+            PropertyMap(), Angle(latitude_projection_centre, angUnit),
+            Angle(longitude_of_origin, angUnit),
+            Angle(colatitude_cone_axis, angUnit),
+            Angle(latitude_pseudo_standard_parallel, angUnit),
+            Scale(scale_factor_pseudo_standard_parallel),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Krovak
+ * projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createKrovak().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_krovak(
+    PJ_CONTEXT *ctx, double latitude_projection_centre,
+    double longitude_of_origin, double colatitude_cone_axis,
+    double latitude_pseudo_standard_parallel,
+    double scale_factor_pseudo_standard_parallel, double false_easting,
+    double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createKrovak(
+            PropertyMap(), Angle(latitude_projection_centre, angUnit),
+            Angle(longitude_of_origin, angUnit),
+            Angle(colatitude_cone_axis, angUnit),
+            Angle(latitude_pseudo_standard_parallel, angUnit),
+            Scale(scale_factor_pseudo_standard_parallel),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Lambert
+ * Azimuthal Equal Area projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createLambertAzimuthalEqualArea().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_lambert_azimuthal_equal_area(
+    PJ_CONTEXT *ctx, double latitude_nat_origin, double longitude_nat_origin,
+    double false_easting, double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createLambertAzimuthalEqualArea(
+            PropertyMap(), Angle(latitude_nat_origin, angUnit),
+            Angle(longitude_nat_origin, angUnit),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Miller
+ * Cylindrical projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createMillerCylindrical().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_miller_cylindrical(
+    PJ_CONTEXT *ctx, double center_long, double false_easting,
+    double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createMillerCylindrical(
+            PropertyMap(), Angle(center_long, angUnit),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Mercator
+ * projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createMercatorVariantA().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_mercator_variant_a(
+    PJ_CONTEXT *ctx, double center_lat, double center_long, double scale,
+    double false_easting, double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createMercatorVariantA(
+            PropertyMap(), Angle(center_lat, angUnit),
+            Angle(center_long, angUnit), Scale(scale),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Mercator
+ * projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createMercatorVariantB().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_mercator_variant_b(
+    PJ_CONTEXT *ctx, double latitude_first_parallel, double center_long,
+    double false_easting, double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createMercatorVariantB(
+            PropertyMap(), Angle(latitude_first_parallel, angUnit),
+            Angle(center_long, angUnit), Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Popular
+ * Visualisation Pseudo Mercator projection method.
+ *
+ * See
+ * osgeo::proj::operation::Conversion::createPopularVisualisationPseudoMercator().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_popular_visualisation_pseudo_mercator(
+    PJ_CONTEXT *ctx, double center_lat, double center_long,
+    double false_easting, double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createPopularVisualisationPseudoMercator(
+            PropertyMap(), Angle(center_lat, angUnit),
+            Angle(center_long, angUnit), Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Mollweide
+ * projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createMollweide().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_mollweide(
+    PJ_CONTEXT *ctx, double center_long, double false_easting,
+    double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createMollweide(
+            PropertyMap(), Angle(center_long, angUnit),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the New Zealand
+ * Map Grid projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createNewZealandMappingGrid().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_new_zealand_mapping_grid(
+    PJ_CONTEXT *ctx, double center_lat, double center_long,
+    double false_easting, double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createNewZealandMappingGrid(
+            PropertyMap(), Angle(center_lat, angUnit),
+            Angle(center_long, angUnit), Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Oblique
+ * Stereographic (Alternative) projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createObliqueStereographic().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_oblique_stereographic(
+    PJ_CONTEXT *ctx, double center_lat, double center_long, double scale,
+    double false_easting, double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createObliqueStereographic(
+            PropertyMap(), Angle(center_lat, angUnit),
+            Angle(center_long, angUnit), Scale(scale),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the
+ * Orthographic projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createOrthographic().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_orthographic(
+    PJ_CONTEXT *ctx, double center_lat, double center_long,
+    double false_easting, double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createOrthographic(
+            PropertyMap(), Angle(center_lat, angUnit),
+            Angle(center_long, angUnit), Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the American
+ * Polyconic projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createAmericanPolyconic().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_american_polyconic(
+    PJ_CONTEXT *ctx, double center_lat, double center_long,
+    double false_easting, double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createAmericanPolyconic(
+            PropertyMap(), Angle(center_lat, angUnit),
+            Angle(center_long, angUnit), Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Polar
+ * Stereographic (Variant A) projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createPolarStereographicVariantA().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_polar_stereographic_variant_a(
+    PJ_CONTEXT *ctx, double center_lat, double center_long, double scale,
+    double false_easting, double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createPolarStereographicVariantA(
+            PropertyMap(), Angle(center_lat, angUnit),
+            Angle(center_long, angUnit), Scale(scale),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Polar
+ * Stereographic (Variant B) projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createPolarStereographicVariantB().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_polar_stereographic_variant_b(
+    PJ_CONTEXT *ctx, double latitude_standard_parallel,
+    double longitude_of_origin, double false_easting, double false_northing,
+    const char *ang_unit_name, double ang_unit_conv_factor,
+    const char *linear_unit_name, double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createPolarStereographicVariantB(
+            PropertyMap(), Angle(latitude_standard_parallel, angUnit),
+            Angle(longitude_of_origin, angUnit),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Robinson
+ * projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createRobinson().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_robinson(PJ_CONTEXT *ctx, double center_long,
+                                            double false_easting,
+                                            double false_northing,
+                                            const char *ang_unit_name,
+                                            double ang_unit_conv_factor,
+                                            const char *linear_unit_name,
+                                            double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createRobinson(
+            PropertyMap(), Angle(center_long, angUnit),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Sinusoidal
+ * projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createSinusoidal().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_sinusoidal(
+    PJ_CONTEXT *ctx, double center_long, double false_easting,
+    double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createSinusoidal(
+            PropertyMap(), Angle(center_long, angUnit),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the
+ * Stereographic projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createStereographic().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_stereographic(
+    PJ_CONTEXT *ctx, double center_lat, double center_long, double scale,
+    double false_easting, double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createStereographic(
+            PropertyMap(), Angle(center_lat, angUnit),
+            Angle(center_long, angUnit), Scale(scale),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Van der
+ * Grinten projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createVanDerGrinten().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_van_der_grinten(
+    PJ_CONTEXT *ctx, double center_long, double false_easting,
+    double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createVanDerGrinten(
+            PropertyMap(), Angle(center_long, angUnit),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Wagner I
+ * projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createWagnerI().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_wagner_i(PJ_CONTEXT *ctx, double center_long,
+                                            double false_easting,
+                                            double false_northing,
+                                            const char *ang_unit_name,
+                                            double ang_unit_conv_factor,
+                                            const char *linear_unit_name,
+                                            double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createWagnerI(
+            PropertyMap(), Angle(center_long, angUnit),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Wagner II
+ * projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createWagnerII().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_wagner_ii(
+    PJ_CONTEXT *ctx, double center_long, double false_easting,
+    double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createWagnerII(
+            PropertyMap(), Angle(center_long, angUnit),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Wagner III
+ * projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createWagnerIII().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_wagner_iii(
+    PJ_CONTEXT *ctx, double latitude_true_scale, double center_long,
+    double false_easting, double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createWagnerIII(
+            PropertyMap(), Angle(latitude_true_scale, angUnit),
+            Angle(center_long, angUnit), Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Wagner IV
+ * projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createWagnerIV().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_wagner_iv(
+    PJ_CONTEXT *ctx, double center_long, double false_easting,
+    double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createWagnerIV(
+            PropertyMap(), Angle(center_long, angUnit),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Wagner V
+ * projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createWagnerV().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_wagner_v(PJ_CONTEXT *ctx, double center_long,
+                                            double false_easting,
+                                            double false_northing,
+                                            const char *ang_unit_name,
+                                            double ang_unit_conv_factor,
+                                            const char *linear_unit_name,
+                                            double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createWagnerV(
+            PropertyMap(), Angle(center_long, angUnit),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Wagner VI
+ * projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createWagnerVI().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_wagner_vi(
+    PJ_CONTEXT *ctx, double center_long, double false_easting,
+    double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createWagnerVI(
+            PropertyMap(), Angle(center_long, angUnit),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Wagner VII
+ * projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createWagnerVII().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_wagner_vii(
+    PJ_CONTEXT *ctx, double center_long, double false_easting,
+    double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createWagnerVII(
+            PropertyMap(), Angle(center_long, angUnit),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the
+ * Quadrilateralized Spherical Cube projection method.
+ *
+ * See
+ * osgeo::proj::operation::Conversion::createQuadrilateralizedSphericalCube().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_quadrilateralized_spherical_cube(
+    PJ_CONTEXT *ctx, double center_lat, double center_long,
+    double false_easting, double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createQuadrilateralizedSphericalCube(
+            PropertyMap(), Angle(center_lat, angUnit),
+            Angle(center_long, angUnit), Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Spherical
+ * Cross-Track Height projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createSphericalCrossTrackHeight().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_spherical_cross_track_height(
+    PJ_CONTEXT *ctx, double peg_point_lat, double peg_point_long,
+    double peg_point_heading, double peg_point_height,
+    const char *ang_unit_name, double ang_unit_conv_factor,
+    const char *linear_unit_name, double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createSphericalCrossTrackHeight(
+            PropertyMap(), Angle(peg_point_lat, angUnit),
+            Angle(peg_point_long, angUnit), Angle(peg_point_heading, angUnit),
+            Length(peg_point_height, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS with a conversion based on the Equal Earth
+ * projection method.
+ *
+ * See osgeo::proj::operation::Conversion::createEqualEarth().
+ *
+ * Linear parameters are expressed in (linear_unit_name,
+ * linear_unit_conv_factor).
+ * Angular parameters are expressed in (ang_unit_name, ang_unit_conv_factor).
+ */
+PJ_OBJ *proj_obj_create_conversion_equal_earth(
+    PJ_CONTEXT *ctx, double center_long, double false_easting,
+    double false_northing, const char *ang_unit_name,
+    double ang_unit_conv_factor, const char *linear_unit_name,
+    double linear_unit_conv_factor) {
+    SANITIZE_CTX(ctx);
+    try {
+        UnitOfMeasure linearUnit(
+            createLinearUnit(linear_unit_name, linear_unit_conv_factor));
+        UnitOfMeasure angUnit(
+            createAngularUnit(ang_unit_name, ang_unit_conv_factor));
+        auto conv = Conversion::createEqualEarth(
+            PropertyMap(), Angle(center_long, angUnit),
+            Length(false_easting, linearUnit),
+            Length(false_northing, linearUnit));
+        return proj_obj_create_conversion(conv);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+/* END: Generated by scripts/create_c_api_projections.py*/
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return whether a coordinate operation can be instanciated as
+ * a PROJ pipeline, checking in particular that referenced grids are
+ * available.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param coordoperation Objet of type CoordinateOperation or derived classes
+ * (must not be NULL)
+ * @return TRUE or FALSE.
+ */
+
+int proj_coordoperation_is_instanciable(PJ_CONTEXT *ctx,
+                                        const PJ_OBJ *coordoperation) {
+    assert(coordoperation);
+    auto op =
+        dynamic_cast<const CoordinateOperation *>(coordoperation->obj.get());
+    if (!op) {
+        proj_log_error(ctx, __FUNCTION__,
+                       "Object is not a CoordinateOperation");
+        return 0;
+    }
+    auto dbContext = getDBcontextNoException(ctx, __FUNCTION__);
+    try {
+        return op->isPROJInstanciable(dbContext) ? 1 : 0;
+    } catch (const std::exception &) {
+        return 0;
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the number of parameters of a SingleOperation
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param coordoperation Objet of type SingleOperation or derived classes
+ * (must not be NULL)
+ */
+
+int proj_coordoperation_get_param_count(PJ_CONTEXT *ctx,
+                                        const PJ_OBJ *coordoperation) {
+    SANITIZE_CTX(ctx);
+    assert(coordoperation);
+    auto op = dynamic_cast<const SingleOperation *>(coordoperation->obj.get());
+    if (!op) {
+        proj_log_error(ctx, __FUNCTION__, "Object is not a SingleOperation");
+        return 0;
+    }
+    return static_cast<int>(op->parameterValues().size());
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the index of a parameter of a SingleOperation
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param coordoperation Objet of type SingleOperation or derived classes
+ * (must not be NULL)
+ * @param name Parameter name. Must not be NULL
+ * @return index (>=0), or -1 in case of error.
+ */
+
+int proj_coordoperation_get_param_index(PJ_CONTEXT *ctx,
+                                        const PJ_OBJ *coordoperation,
+                                        const char *name) {
+    SANITIZE_CTX(ctx);
+    assert(coordoperation);
+    assert(name);
+    auto op = dynamic_cast<const SingleOperation *>(coordoperation->obj.get());
+    if (!op) {
+        proj_log_error(ctx, __FUNCTION__, "Object is not a SingleOperation");
+        return -1;
+    }
+    int index = 0;
+    for (const auto &genParam : op->method()->parameters()) {
+        if (Identifier::isEquivalentName(genParam->nameStr().c_str(), name)) {
+            return index;
+        }
+        index++;
+    }
+    return -1;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return a parameter of a SingleOperation
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param coordoperation Objet of type SingleOperation or derived classes
+ * (must not be NULL)
+ * @param index Parameter index.
+ * @param out_name Pointer to a string value to store the parameter name. or
+ * NULL
+ * @param out_auth_name Pointer to a string value to store the parameter
+ * authority name. or NULL
+ * @param out_code Pointer to a string value to store the parameter
+ * code. or NULL
+ * @param out_value Pointer to a double value to store the parameter
+ * value (if numeric). or NULL
+ * @param out_value_string Pointer to a string value to store the parameter
+ * value (if of type string). or NULL
+ * @param out_unit_conv_factor Pointer to a double value to store the parameter
+ * unit conversion factor. or NULL
+ * @param out_unit_name Pointer to a string value to store the parameter
+ * unit name. or NULL
+ * @param out_unit_auth_name Pointer to a string value to store the
+ * unit authority name. or NULL
+ * @param out_unit_code Pointer to a string value to store the
+ * unit code. or NULL
+ * @param out_unit_category Pointer to a string value to store the parameter
+ * name. or
+ * NULL. This value might be "unknown", "none", "linear", "angular", "scale",
+ * "time" or "parametric";
+ * @return TRUE in case of success.
+ */
+
+int proj_coordoperation_get_param(
+    PJ_CONTEXT *ctx, const PJ_OBJ *coordoperation, int index,
+    const char **out_name, const char **out_auth_name, const char **out_code,
+    double *out_value, const char **out_value_string,
+    double *out_unit_conv_factor, const char **out_unit_name,
+    const char **out_unit_auth_name, const char **out_unit_code,
+    const char **out_unit_category) {
+    SANITIZE_CTX(ctx);
+    assert(coordoperation);
+    auto op = dynamic_cast<const SingleOperation *>(coordoperation->obj.get());
+    if (!op) {
+        proj_log_error(ctx, __FUNCTION__, "Object is not a SingleOperation");
+        return false;
+    }
+    const auto &parameters = op->method()->parameters();
+    const auto &values = op->parameterValues();
+    if (static_cast<size_t>(index) >= parameters.size() ||
+        static_cast<size_t>(index) >= values.size()) {
+        proj_log_error(ctx, __FUNCTION__, "Invalid index");
+        return false;
+    }
+
+    const auto &param = parameters[index];
+    const auto &param_ids = param->identifiers();
+    if (out_name) {
+        *out_name = param->name()->description()->c_str();
+    }
+    if (out_auth_name) {
+        if (!param_ids.empty()) {
+            *out_auth_name = param_ids[0]->codeSpace()->c_str();
+        } else {
+            *out_auth_name = nullptr;
+        }
+    }
+    if (out_code) {
+        if (!param_ids.empty()) {
+            *out_code = param_ids[0]->code().c_str();
+        } else {
+            *out_code = nullptr;
+        }
+    }
+
+    const auto &value = values[index];
+    ParameterValuePtr paramValue = nullptr;
+    auto opParamValue =
+        dynamic_cast<const OperationParameterValue *>(value.get());
+    if (opParamValue) {
+        paramValue = opParamValue->parameterValue().as_nullable();
+    }
+    if (out_value) {
+        *out_value = 0;
+        if (paramValue) {
+            if (paramValue->type() == ParameterValue::Type::MEASURE) {
+                *out_value = paramValue->value().value();
+            }
+        }
+    }
+    if (out_value_string) {
+        *out_value_string = nullptr;
+        if (paramValue) {
+            if (paramValue->type() == ParameterValue::Type::FILENAME) {
+                *out_value_string = paramValue->valueFile().c_str();
+            } else if (paramValue->type() == ParameterValue::Type::STRING) {
+                *out_value_string = paramValue->stringValue().c_str();
+            }
+        }
+    }
+    if (out_unit_conv_factor) {
+        *out_unit_conv_factor = 0;
+    }
+    if (out_unit_name) {
+        *out_unit_name = nullptr;
+    }
+    if (out_unit_auth_name) {
+        *out_unit_auth_name = nullptr;
+    }
+    if (out_unit_code) {
+        *out_unit_code = nullptr;
+    }
+    if (out_unit_category) {
+        *out_unit_category = nullptr;
+    }
+    if (paramValue) {
+        if (paramValue->type() == ParameterValue::Type::MEASURE) {
+            const auto &unit = paramValue->value().unit();
+            if (out_unit_conv_factor) {
+                *out_unit_conv_factor = unit.conversionToSI();
+            }
+            if (out_unit_name) {
+                *out_unit_name = unit.name().c_str();
+            }
+            if (out_unit_auth_name) {
+                *out_unit_auth_name = unit.codeSpace().c_str();
+            }
+            if (out_unit_code) {
+                *out_unit_code = unit.code().c_str();
+            }
+            if (out_unit_category) {
+                *out_unit_category = get_unit_category(unit.type());
+            }
+        }
+    }
+
+    return true;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the parameters of a Helmert transformation as WKT1 TOWGS84
+ * values.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param coordoperation Objet of type Transformation, that can be represented
+ * as a WKT1 TOWGS84 node (must not be NULL)
+ * @param out_values Pointer to an array of value_count double values.
+ * @param value_count Size of out_values array.
+ * @param emit_error_if_incompatible Boolean to inicate if an error must be
+ * logged if coordoperation is not compatible with a WKT1 TOWGS84
+ * representation.
+ * @return TRUE in case of success, or FALSE if coordoperation is not
+ * compatible with a WKT1 TOWGS84 representation.
+ */
+
+int proj_coordoperation_get_towgs84_values(PJ_CONTEXT *ctx,
+                                           const PJ_OBJ *coordoperation,
+                                           double *out_values, int value_count,
+                                           int emit_error_if_incompatible) {
+    SANITIZE_CTX(ctx);
+    assert(coordoperation);
+    auto transf =
+        dynamic_cast<const Transformation *>(coordoperation->obj.get());
+    if (!transf) {
+        if (emit_error_if_incompatible) {
+            proj_log_error(ctx, __FUNCTION__, "Object is not a Transformation");
+        }
+        return FALSE;
+    }
+    try {
+        auto values = transf->getTOWGS84Parameters();
+        for (int i = 0;
+             i < value_count && static_cast<size_t>(i) < values.size(); i++) {
+            out_values[i] = values[i];
+        }
+        return TRUE;
+    } catch (const std::exception &e) {
+        if (emit_error_if_incompatible) {
+            proj_log_error(ctx, __FUNCTION__, e.what());
+        }
+        return FALSE;
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the number of grids used by a CoordinateOperation
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param coordoperation Objet of type CoordinateOperation or derived classes
+ * (must not be NULL)
+ */
+
+int proj_coordoperation_get_grid_used_count(PJ_CONTEXT *ctx,
+                                            const PJ_OBJ *coordoperation) {
+    SANITIZE_CTX(ctx);
+    assert(coordoperation);
+    auto co =
+        dynamic_cast<const CoordinateOperation *>(coordoperation->obj.get());
+    if (!co) {
+        proj_log_error(ctx, __FUNCTION__,
+                       "Object is not a CoordinateOperation");
+        return 0;
+    }
+    auto dbContext = getDBcontextNoException(ctx, __FUNCTION__);
+    try {
+        if (!coordoperation->gridsNeededAsked) {
+            coordoperation->gridsNeededAsked = true;
+            const auto gridsNeeded = co->gridsNeeded(dbContext);
+            for (const auto &gridDesc : gridsNeeded) {
+                coordoperation->gridsNeeded.emplace_back(gridDesc);
+            }
+        }
+        return static_cast<int>(coordoperation->gridsNeeded.size());
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+        return 0;
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return a parameter of a SingleOperation
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param coordoperation Objet of type SingleOperation or derived classes
+ * (must not be NULL)
+ * @param index Parameter index.
+ * @param out_short_name Pointer to a string value to store the grid short name.
+ * or NULL
+ * @param out_full_name Pointer to a string value to store the grid full
+ * filename. or NULL
+ * @param out_package_name Pointer to a string value to store the package name
+ * where
+ * the grid might be found. or NULL
+ * @param out_url Pointer to a string value to store the grid URL or the
+ * package URL where the grid might be found. or NULL
+ * @param out_direct_download Pointer to a int (boolean) value to store whether
+ * *out_url can be downloaded directly. or NULL
+ * @param out_open_license Pointer to a int (boolean) value to store whether
+ * the grid is released with an open license. or NULL
+ * @param out_available Pointer to a int (boolean) value to store whether the
+ * grid is available at runtime. or NULL
+ * @return TRUE in case of success.
+ */
+
+int proj_coordoperation_get_grid_used(
+    PJ_CONTEXT *ctx, const PJ_OBJ *coordoperation, int index,
+    const char **out_short_name, const char **out_full_name,
+    const char **out_package_name, const char **out_url,
+    int *out_direct_download, int *out_open_license, int *out_available) {
+    SANITIZE_CTX(ctx);
+    const int count =
+        proj_coordoperation_get_grid_used_count(ctx, coordoperation);
+    if (index < 0 || index >= count) {
+        proj_log_error(ctx, __FUNCTION__, "Invalid index");
+        return false;
+    }
+
+    const auto &gridDesc = coordoperation->gridsNeeded[index];
+    if (out_short_name) {
+        *out_short_name = gridDesc.shortName.c_str();
+    }
+
+    if (out_full_name) {
+        *out_full_name = gridDesc.fullName.c_str();
+    }
+
+    if (out_package_name) {
+        *out_package_name = gridDesc.packageName.c_str();
+    }
+
+    if (out_url) {
+        *out_url = gridDesc.url.c_str();
+    }
+
+    if (out_direct_download) {
+        *out_direct_download = gridDesc.directDownload;
+    }
+
+    if (out_open_license) {
+        *out_open_license = gridDesc.openLicense;
+    }
+
+    if (out_available) {
+        *out_available = gridDesc.available;
+    }
+
+    return true;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Opaque object representing an operation factory context. */
+struct PJ_OPERATION_FACTORY_CONTEXT {
+    //! @cond Doxygen_Suppress
+    CoordinateOperationContextNNPtr operationContext;
+
+    explicit PJ_OPERATION_FACTORY_CONTEXT(
+        CoordinateOperationContextNNPtr &&operationContextIn)
+        : operationContext(std::move(operationContextIn)) {}
+
+    PJ_OPERATION_FACTORY_CONTEXT(const PJ_OPERATION_FACTORY_CONTEXT &) = delete;
+    PJ_OPERATION_FACTORY_CONTEXT &
+    operator=(const PJ_OPERATION_FACTORY_CONTEXT &) = delete;
+    //! @endcond
+};
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a context for building coordinate operations between
+ * two CRS.
+ *
+ * The returned object must be unreferenced with
+ * proj_operation_factory_context_destroy() after use.
+ *
+ * If authority is NULL or the empty string, then coordinate
+ * operations from any authority will be searched, with the restrictions set
+ * in the authority_to_authority_preference database table.
+ * If authority is set to "any", then coordinate
+ * operations from any authority will be searched
+ * If authority is a non-empty string different of "any",
+ * then coordinate operatiosn will be searched only in that authority namespace.
+ *
+ * @param ctx Context, or NULL for default context.
+ * @param authority Name of authority to which to restrict the search of
+ *                  candidate operations.
+ * @return Object that must be unreferenced with
+ * proj_operation_factory_context_destroy(), or NULL in
+ * case of error.
+ */
+PJ_OPERATION_FACTORY_CONTEXT *
+proj_create_operation_factory_context(PJ_CONTEXT *ctx, const char *authority) {
+    SANITIZE_CTX(ctx);
+    auto dbContext = getDBcontextNoException(ctx, __FUNCTION__);
+    try {
+        if (dbContext) {
+            auto factory = CoordinateOperationFactory::create();
+            auto authFactory = AuthorityFactory::create(
+                NN_NO_CHECK(dbContext),
+                std::string(authority ? authority : ""));
+            auto operationContext =
+                CoordinateOperationContext::create(authFactory, nullptr, 0.0);
+            return new PJ_OPERATION_FACTORY_CONTEXT(
+                std::move(operationContext));
+        } else {
+            auto operationContext =
+                CoordinateOperationContext::create(nullptr, nullptr, 0.0);
+            return new PJ_OPERATION_FACTORY_CONTEXT(
+                std::move(operationContext));
+        }
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Drops a reference on an object.
+ *
+ * This method should be called one and exactly one for each function
+ * returning a PJ_OPERATION_FACTORY_CONTEXT*
+ *
+ * @param ctx Object, or NULL.
+ */
+void proj_operation_factory_context_destroy(PJ_OPERATION_FACTORY_CONTEXT *ctx) {
+    delete ctx;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Set the desired accuracy of the resulting coordinate transformations.
+ * @param ctx PROJ context, or NULL for default context
+ * @param factory_ctx Operation factory context. must not be NULL
+ * @param accuracy Accuracy in meter (or 0 to disable the filter).
+ */
+void proj_operation_factory_context_set_desired_accuracy(
+    PJ_CONTEXT *ctx, PJ_OPERATION_FACTORY_CONTEXT *factory_ctx,
+    double accuracy) {
+    SANITIZE_CTX(ctx);
+    assert(factory_ctx);
+    try {
+        factory_ctx->operationContext->setDesiredAccuracy(accuracy);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Set the desired area of interest for the resulting coordinate
+ * transformations.
+ *
+ * For an area of interest crossing the anti-meridian, west_lon_degree will be
+ * greater than east_lon_degree.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param factory_ctx Operation factory context. must not be NULL
+ * @param west_lon_degree West longitude (in degrees).
+ * @param south_lat_degree South latitude (in degrees).
+ * @param east_lon_degree East longitude (in degrees).
+ * @param north_lat_degree North latitude (in degrees).
+ */
+void proj_operation_factory_context_set_area_of_interest(
+    PJ_CONTEXT *ctx, PJ_OPERATION_FACTORY_CONTEXT *factory_ctx,
+    double west_lon_degree, double south_lat_degree, double east_lon_degree,
+    double north_lat_degree) {
+    SANITIZE_CTX(ctx);
+    assert(factory_ctx);
+    try {
+        factory_ctx->operationContext->setAreaOfInterest(
+            Extent::createFromBBOX(west_lon_degree, south_lat_degree,
+                                   east_lon_degree, north_lat_degree));
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Set how source and target CRS extent should be used
+ * when considering if a transformation can be used (only takes effect if
+ * no area of interest is explicitly defined).
+ *
+ * The default is PJ_CRS_EXTENT_SMALLEST.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param factory_ctx Operation factory context. must not be NULL
+ * @param use How source and target CRS extent should be used.
+ */
+void proj_operation_factory_context_set_crs_extent_use(
+    PJ_CONTEXT *ctx, PJ_OPERATION_FACTORY_CONTEXT *factory_ctx,
+    PROJ_CRS_EXTENT_USE use) {
+    SANITIZE_CTX(ctx);
+    assert(factory_ctx);
+    try {
+        switch (use) {
+        case PJ_CRS_EXTENT_NONE:
+            factory_ctx->operationContext->setSourceAndTargetCRSExtentUse(
+                CoordinateOperationContext::SourceTargetCRSExtentUse::NONE);
+            break;
+
+        case PJ_CRS_EXTENT_BOTH:
+            factory_ctx->operationContext->setSourceAndTargetCRSExtentUse(
+                CoordinateOperationContext::SourceTargetCRSExtentUse::BOTH);
+            break;
+
+        case PJ_CRS_EXTENT_INTERSECTION:
+            factory_ctx->operationContext->setSourceAndTargetCRSExtentUse(
+                CoordinateOperationContext::SourceTargetCRSExtentUse::
+                    INTERSECTION);
+            break;
+
+        case PJ_CRS_EXTENT_SMALLEST:
+            factory_ctx->operationContext->setSourceAndTargetCRSExtentUse(
+                CoordinateOperationContext::SourceTargetCRSExtentUse::SMALLEST);
+            break;
+        }
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Set the spatial criterion to use when comparing the area of
+ * validity of coordinate operations with the area of interest / area of
+ * validity of
+ * source and target CRS.
+ *
+ * The default is PROJ_SPATIAL_CRITERION_STRICT_CONTAINMENT.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param factory_ctx Operation factory context. must not be NULL
+ * @param criterion patial criterion to use
+ */
+void PROJ_DLL proj_operation_factory_context_set_spatial_criterion(
+    PJ_CONTEXT *ctx, PJ_OPERATION_FACTORY_CONTEXT *factory_ctx,
+    PROJ_SPATIAL_CRITERION criterion) {
+    SANITIZE_CTX(ctx);
+    assert(factory_ctx);
+    try {
+        switch (criterion) {
+        case PROJ_SPATIAL_CRITERION_STRICT_CONTAINMENT:
+            factory_ctx->operationContext->setSpatialCriterion(
+                CoordinateOperationContext::SpatialCriterion::
+                    STRICT_CONTAINMENT);
+            break;
+
+        case PROJ_SPATIAL_CRITERION_PARTIAL_INTERSECTION:
+            factory_ctx->operationContext->setSpatialCriterion(
+                CoordinateOperationContext::SpatialCriterion::
+                    PARTIAL_INTERSECTION);
+            break;
+        }
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Set how grid availability is used.
+ *
+ * The default is USE_FOR_SORTING.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param factory_ctx Operation factory context. must not be NULL
+ * @param use how grid availability is used.
+ */
+void PROJ_DLL proj_operation_factory_context_set_grid_availability_use(
+    PJ_CONTEXT *ctx, PJ_OPERATION_FACTORY_CONTEXT *factory_ctx,
+    PROJ_GRID_AVAILABILITY_USE use) {
+    SANITIZE_CTX(ctx);
+    assert(factory_ctx);
+    try {
+        switch (use) {
+        case PROJ_GRID_AVAILABILITY_USED_FOR_SORTING:
+            factory_ctx->operationContext->setGridAvailabilityUse(
+                CoordinateOperationContext::GridAvailabilityUse::
+                    USE_FOR_SORTING);
+            break;
+
+        case PROJ_GRID_AVAILABILITY_DISCARD_OPERATION_IF_MISSING_GRID:
+            factory_ctx->operationContext->setGridAvailabilityUse(
+                CoordinateOperationContext::GridAvailabilityUse::
+                    DISCARD_OPERATION_IF_MISSING_GRID);
+            break;
+
+        case PROJ_GRID_AVAILABILITY_IGNORED:
+            factory_ctx->operationContext->setGridAvailabilityUse(
+                CoordinateOperationContext::GridAvailabilityUse::
+                    IGNORE_GRID_AVAILABILITY);
+            break;
+        }
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Set whether PROJ alternative grid names should be substituted to
+ * the official authority names.
+ *
+ * The default is true.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param factory_ctx Operation factory context. must not be NULL
+ * @param usePROJNames whether PROJ alternative grid names should be used
+ */
+void proj_operation_factory_context_set_use_proj_alternative_grid_names(
+    PJ_CONTEXT *ctx, PJ_OPERATION_FACTORY_CONTEXT *factory_ctx,
+    int usePROJNames) {
+    SANITIZE_CTX(ctx);
+    assert(factory_ctx);
+    try {
+        factory_ctx->operationContext->setUsePROJAlternativeGridNames(
+            usePROJNames != 0);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Set whether an intermediate pivot CRS can be used for researching
+ * coordinate operations between a source and target CRS.
+ *
+ * Concretely if in the database there is an operation from A to C
+ * (or C to A), and another one from C to B (or B to C), but no direct
+ * operation between A and B, setting this parameter to true, allow
+ * chaining both operations.
+ *
+ * The current implementation is limited to researching one intermediate
+ * step.
+ *
+ * By default, all potential C candidates will be used.
+ * proj_operation_factory_context_set_allowed_intermediate_crs()
+ * can be used to restrict them.
+ *
+ * The default is true.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param factory_ctx Operation factory context. must not be NULL
+ * @param allow whether intermediate CRS may be used.
+ */
+void proj_operation_factory_context_set_allow_use_intermediate_crs(
+    PJ_CONTEXT *ctx, PJ_OPERATION_FACTORY_CONTEXT *factory_ctx, int allow) {
+    SANITIZE_CTX(ctx);
+    assert(factory_ctx);
+    try {
+        factory_ctx->operationContext->setAllowUseIntermediateCRS(allow != 0);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Restrict the potential pivot CRSs that can be used when trying to
+ * build a coordinate operation between two CRS that have no direct operation.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param factory_ctx Operation factory context. must not be NULL
+ * @param list_of_auth_name_codes an array of strings NLL terminated,
+ * with the format { "auth_name1", "code1", "auth_name2", "code2", ... NULL }
+ */
+void proj_operation_factory_context_set_allowed_intermediate_crs(
+    PJ_CONTEXT *ctx, PJ_OPERATION_FACTORY_CONTEXT *factory_ctx,
+    const char *const *list_of_auth_name_codes) {
+    SANITIZE_CTX(ctx);
+    assert(factory_ctx);
+    try {
+        std::vector<std::pair<std::string, std::string>> pivots;
+        for (auto iter = list_of_auth_name_codes; iter && iter[0] && iter[1];
+             iter += 2) {
+            pivots.emplace_back(std::pair<std::string, std::string>(
+                std::string(iter[0]), std::string(iter[1])));
+        }
+        factory_ctx->operationContext->setIntermediateCRS(pivots);
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Find a list of CoordinateOperation from source_crs to target_crs.
+ *
+ * The operations are sorted with the most relevant ones first: by
+ * descending
+ * area (intersection of the transformation area with the area of interest,
+ * or intersection of the transformation with the area of use of the CRS),
+ * and
+ * by increasing accuracy. Operations with unknown accuracy are sorted last,
+ * whatever their area.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param source_crs source CRS. Must not be NULL.
+ * @param target_crs source CRS. Must not be NULL.
+ * @param operationContext Search context. Must not be NULL.
+ * @return a result set that must be unreferenced with
+ * proj_obj_list_destroy(), or NULL in case of error.
+ */
+PJ_OBJ_LIST *proj_obj_create_operations(
+    PJ_CONTEXT *ctx, const PJ_OBJ *source_crs, const PJ_OBJ *target_crs,
+    const PJ_OPERATION_FACTORY_CONTEXT *operationContext) {
+    SANITIZE_CTX(ctx);
+    assert(source_crs);
+    assert(target_crs);
+    assert(operationContext);
+
+    auto sourceCRS = nn_dynamic_pointer_cast<CRS>(source_crs->obj);
+    if (!sourceCRS) {
+        proj_log_error(ctx, __FUNCTION__, "source_crs is not a CRS");
+        return nullptr;
+    }
+    auto targetCRS = nn_dynamic_pointer_cast<CRS>(target_crs->obj);
+    if (!targetCRS) {
+        proj_log_error(ctx, __FUNCTION__, "target_crs is not a CRS");
+        return nullptr;
+    }
+
+    try {
+        auto factory = CoordinateOperationFactory::create();
+        std::vector<IdentifiedObjectNNPtr> objects;
+        auto ops = factory->createOperations(
+            NN_NO_CHECK(sourceCRS), NN_NO_CHECK(targetCRS),
+            operationContext->operationContext);
+        for (const auto &op : ops) {
+            objects.emplace_back(op);
+        }
+        return new PJ_OBJ_LIST(std::move(objects));
+    } catch (const std::exception &e) {
+        proj_log_error(ctx, __FUNCTION__, e.what());
+        return nullptr;
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the number of objects in the result set
+ *
+ * @param result Objet of type PJ_OBJ_LIST (must not be NULL)
+ */
+int proj_obj_list_get_count(const PJ_OBJ_LIST *result) {
+    assert(result);
+    return static_cast<int>(result->objects.size());
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return an object from the result set
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after
+ * use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param result Objet of type PJ_OBJ_LIST (must not be NULL)
+ * @param index Index
+ * @return a new object that must be unreferenced with proj_obj_destroy(),
+ * or nullptr in case of error.
+ */
+
+PJ_OBJ *proj_obj_list_get(PJ_CONTEXT *ctx, const PJ_OBJ_LIST *result,
+                          int index) {
+    SANITIZE_CTX(ctx);
+    assert(result);
+    if (index < 0 || index >= proj_obj_list_get_count(result)) {
+        proj_log_error(ctx, __FUNCTION__, "Invalid index");
+        return nullptr;
+    }
+    return PJ_OBJ::create(result->objects[index]);
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Drops a reference on the result set.
+ *
+ * This method should be called one and exactly one for each function
+ * returning a PJ_OBJ_LIST*
+ *
+ * @param result Object, or NULL.
+ */
+void proj_obj_list_destroy(PJ_OBJ_LIST *result) { delete result; }
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the accuracy (in metre) of a coordinate operation.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param coordoperation Coordinate operation. Must not be NULL.
+ * @return the accuracy, or a negative value if unknown or in case of error.
+ */
+double proj_coordoperation_get_accuracy(PJ_CONTEXT *ctx,
+                                        const PJ_OBJ *coordoperation) {
+    SANITIZE_CTX(ctx);
+    assert(coordoperation);
+    auto co =
+        dynamic_cast<const CoordinateOperation *>(coordoperation->obj.get());
+    if (!co) {
+        proj_log_error(ctx, __FUNCTION__,
+                       "Object is not a CoordinateOperation");
+        return -1;
+    }
+    const auto &accuracies = co->coordinateOperationAccuracies();
+    if (accuracies.empty()) {
+        return -1;
+    }
+    try {
+        return c_locale_stod(accuracies[0]->value());
+    } catch (const std::exception &) {
+    }
+    return -1;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns the datum of a SingleCRS.
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after
+ * use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param crs Objet of type SingleCRS (must not be NULL)
+ * @return Object that must be unreferenced with proj_obj_destroy(), or NULL
+ * in case of error (or if there is no datum)
+ */
+PJ_OBJ *proj_obj_crs_get_datum(PJ_CONTEXT *ctx, const PJ_OBJ *crs) {
+    SANITIZE_CTX(ctx);
+    assert(crs);
+    auto l_crs = dynamic_cast<const SingleCRS *>(crs->obj.get());
+    if (!l_crs) {
+        proj_log_error(ctx, __FUNCTION__, "Object is not a SingleCRS");
+        return nullptr;
+    }
+    const auto &datum = l_crs->datum();
+    if (!datum) {
+        return nullptr;
+    }
+    return PJ_OBJ::create(NN_NO_CHECK(datum));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns the coordinate system of a SingleCRS.
+ *
+ * The returned object must be unreferenced with proj_obj_destroy() after
+ * use.
+ * It should be used by at most one thread at a time.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param crs Objet of type SingleCRS (must not be NULL)
+ * @return Object that must be unreferenced with proj_obj_destroy(), or NULL
+ * in case of error.
+ */
+PJ_OBJ *proj_obj_crs_get_coordinate_system(PJ_CONTEXT *ctx, const PJ_OBJ *crs) {
+    SANITIZE_CTX(ctx);
+    assert(crs);
+    auto l_crs = dynamic_cast<const SingleCRS *>(crs->obj.get());
+    if (!l_crs) {
+        proj_log_error(ctx, __FUNCTION__, "Object is not a SingleCRS");
+        return nullptr;
+    }
+    return PJ_OBJ::create(l_crs->coordinateSystem());
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns the type of the coordinate system.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param cs Objet of type CoordinateSystem (must not be NULL)
+ * @return type, or PJ_CS_TYPE_UNKNOWN in case of error.
+ */
+PJ_COORDINATE_SYSTEM_TYPE proj_obj_cs_get_type(PJ_CONTEXT *ctx,
+                                               const PJ_OBJ *cs) {
+    SANITIZE_CTX(ctx);
+    assert(cs);
+    auto l_cs = dynamic_cast<const CoordinateSystem *>(cs->obj.get());
+    if (!l_cs) {
+        proj_log_error(ctx, __FUNCTION__, "Object is not a CoordinateSystem");
+        return PJ_CS_TYPE_UNKNOWN;
+    }
+    if (dynamic_cast<const CartesianCS *>(l_cs)) {
+        return PJ_CS_TYPE_CARTESIAN;
+    }
+    if (dynamic_cast<const EllipsoidalCS *>(l_cs)) {
+        return PJ_CS_TYPE_ELLIPSOIDAL;
+    }
+    if (dynamic_cast<const VerticalCS *>(l_cs)) {
+        return PJ_CS_TYPE_VERTICAL;
+    }
+    if (dynamic_cast<const SphericalCS *>(l_cs)) {
+        return PJ_CS_TYPE_SPHERICAL;
+    }
+    if (dynamic_cast<const OrdinalCS *>(l_cs)) {
+        return PJ_CS_TYPE_ORDINAL;
+    }
+    if (dynamic_cast<const ParametricCS *>(l_cs)) {
+        return PJ_CS_TYPE_PARAMETRIC;
+    }
+    if (dynamic_cast<const DateTimeTemporalCS *>(l_cs)) {
+        return PJ_CS_TYPE_DATETIMETEMPORAL;
+    }
+    if (dynamic_cast<const TemporalCountCS *>(l_cs)) {
+        return PJ_CS_TYPE_TEMPORALCOUNT;
+    }
+    if (dynamic_cast<const TemporalMeasureCS *>(l_cs)) {
+        return PJ_CS_TYPE_TEMPORALMEASURE;
+    }
+    return PJ_CS_TYPE_UNKNOWN;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns the number of axis of the coordinate system.
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param cs Objet of type CoordinateSystem (must not be NULL)
+ * @return number of axis, or -1 in case of error.
+ */
+int proj_obj_cs_get_axis_count(PJ_CONTEXT *ctx, const PJ_OBJ *cs) {
+    SANITIZE_CTX(ctx);
+    assert(cs);
+    auto l_cs = dynamic_cast<const CoordinateSystem *>(cs->obj.get());
+    if (!l_cs) {
+        proj_log_error(ctx, __FUNCTION__, "Object is not a CoordinateSystem");
+        return -1;
+    }
+    return static_cast<int>(l_cs->axisList().size());
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns information on an axis
+ *
+ * @param ctx PROJ context, or NULL for default context
+ * @param cs Objet of type CoordinateSystem (must not be NULL)
+ * @param index Index of the coordinate system (between 0 and
+ * proj_obj_cs_get_axis_count() - 1)
+ * @param out_name Pointer to a string value to store the axis name. or NULL
+ * @param out_abbrev Pointer to a string value to store the axis abbreviation.
+ * or NULL
+ * @param out_direction Pointer to a string value to store the axis direction.
+ * or NULL
+ * @param out_unit_conv_factor Pointer to a double value to store the axis
+ * unit conversion factor. or NULL
+ * @param out_unit_name Pointer to a string value to store the axis
+ * unit name. or NULL
+ * @param out_unit_auth_name Pointer to a string value to store the axis
+ * unit authority name. or NULL
+ * @param out_unit_code Pointer to a string value to store the axis
+ * unit code. or NULL
+ * @return TRUE in case of success
+ */
+int proj_obj_cs_get_axis_info(PJ_CONTEXT *ctx, const PJ_OBJ *cs, int index,
+                              const char **out_name, const char **out_abbrev,
+                              const char **out_direction,
+                              double *out_unit_conv_factor,
+                              const char **out_unit_name,
+                              const char **out_unit_auth_name,
+                              const char **out_unit_code) {
+    SANITIZE_CTX(ctx);
+    assert(cs);
+    auto l_cs = dynamic_cast<const CoordinateSystem *>(cs->obj.get());
+    if (!l_cs) {
+        proj_log_error(ctx, __FUNCTION__, "Object is not a CoordinateSystem");
+        return false;
+    }
+    const auto &axisList = l_cs->axisList();
+    if (index < 0 || static_cast<size_t>(index) >= axisList.size()) {
+        proj_log_error(ctx, __FUNCTION__, "Invalid index");
+        return false;
+    }
+    const auto &axis = axisList[index];
+    if (out_name) {
+        *out_name = axis->nameStr().c_str();
+    }
+    if (out_abbrev) {
+        *out_abbrev = axis->abbreviation().c_str();
+    }
+    if (out_direction) {
+        *out_direction = axis->direction().toString().c_str();
+    }
+    if (out_unit_conv_factor) {
+        *out_unit_conv_factor = axis->unit().conversionToSI();
+    }
+    if (out_unit_name) {
+        *out_unit_name = axis->unit().name().c_str();
+    }
+    if (out_unit_auth_name) {
+        *out_unit_auth_name = axis->unit().codeSpace().c_str();
+    }
+    if (out_unit_code) {
+        *out_unit_code = axis->unit().code().c_str();
+    }
+    return true;
+}
diff --git a/src/iso19111/common.cpp b/src/iso19111/common.cpp
new file mode 100644
index 00000000..bd690924
--- /dev/null
+++ b/src/iso19111/common.cpp
@@ -0,0 +1,1115 @@
+/******************************************************************************
+ *
+ * Project:  PROJ
+ * Purpose:  ISO19111:2018 implementation
+ * Author:   Even Rouault <even dot rouault at spatialys dot com>
+ *
+ ******************************************************************************
+ * Copyright (c) 2018, Even Rouault <even dot rouault at spatialys dot com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ ****************************************************************************/
+
+#ifndef FROM_PROJ_CPP
+#define FROM_PROJ_CPP
+#endif
+
+#include "proj/common.hpp"
+#include "proj/io.hpp"
+#include "proj/metadata.hpp"
+#include "proj/util.hpp"
+
+#include "proj/internal/internal.hpp"
+#include "proj/internal/io_internal.hpp"
+
+#include "proj.h"
+
+#include <cmath> // M_PI
+#include <cstdlib>
+#include <memory>
+#include <string>
+#include <vector>
+
+using namespace NS_PROJ::internal;
+using namespace NS_PROJ::io;
+using namespace NS_PROJ::metadata;
+using namespace NS_PROJ::util;
+
+#if 0
+namespace dropbox{ namespace oxygen {
+template<> nn<NS_PROJ::common::IdentifiedObjectPtr>::~nn() = default;
+template<> nn<NS_PROJ::common::ObjectDomainPtr>::~nn() = default;
+template<> nn<NS_PROJ::common::ObjectUsagePtr>::~nn() = default;
+template<> nn<NS_PROJ::common::UnitOfMeasurePtr>::~nn() = default;
+}}
+#endif
+
+NS_PROJ_START
+namespace common {
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct UnitOfMeasure::Private {
+    std::string name_{};
+    double toSI_ = 1.0;
+    UnitOfMeasure::Type type_{UnitOfMeasure::Type::UNKNOWN};
+    std::string codeSpace_{};
+    std::string code_{};
+
+    Private(const std::string &nameIn, double toSIIn,
+            UnitOfMeasure::Type typeIn, const std::string &codeSpaceIn,
+            const std::string &codeIn)
+        : name_(nameIn), toSI_(toSIIn), type_(typeIn), codeSpace_(codeSpaceIn),
+          code_(codeIn) {}
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Creates a UnitOfMeasure. */
+UnitOfMeasure::UnitOfMeasure(const std::string &nameIn, double toSIIn,
+                             UnitOfMeasure::Type typeIn,
+                             const std::string &codeSpaceIn,
+                             const std::string &codeIn)
+    : d(internal::make_unique<Private>(nameIn, toSIIn, typeIn, codeSpaceIn,
+                                       codeIn)) {}
+
+// ---------------------------------------------------------------------------
+
+UnitOfMeasure::UnitOfMeasure(const UnitOfMeasure &other)
+    : d(internal::make_unique<Private>(*(other.d))) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+UnitOfMeasure::~UnitOfMeasure() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+UnitOfMeasure &UnitOfMeasure::operator=(const UnitOfMeasure &other) {
+    if (this != &other) {
+        *d = *(other.d);
+    }
+    return *this;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+UnitOfMeasureNNPtr UnitOfMeasure::create(const UnitOfMeasure &other) {
+    return util::nn_make_shared<UnitOfMeasure>(other);
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the name of the unit of measure. */
+const std::string &UnitOfMeasure::name() PROJ_PURE_DEFN { return d->name_; }
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the conversion factor to the unit of the
+ * International System of Units of the same Type.
+ *
+ * For example, for foot, this would be 0.3048 (metre)
+ *
+ * @return the conversion factor, or 0 if no conversion exists.
+ */
+double UnitOfMeasure::conversionToSI() PROJ_PURE_DEFN { return d->toSI_; }
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the type of the unit of measure.
+ */
+UnitOfMeasure::Type UnitOfMeasure::type() PROJ_PURE_DEFN { return d->type_; }
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the code space of the unit of measure.
+ *
+ * For example "EPSG"
+ *
+ * @return the code space, or empty string.
+ */
+const std::string &UnitOfMeasure::codeSpace() PROJ_PURE_DEFN {
+    return d->codeSpace_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the code of the unit of measure.
+ *
+ * @return the code, or empty string.
+ */
+const std::string &UnitOfMeasure::code() PROJ_PURE_DEFN { return d->code_; }
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void UnitOfMeasure::_exportToWKT(
+    WKTFormatter *formatter,
+    const std::string &unitType) const // throw(FormattingException)
+{
+    const bool isWKT2 = formatter->version() == WKTFormatter::Version::WKT2;
+
+    if (formatter->forceUNITKeyword() && type() != Type::PARAMETRIC) {
+        formatter->startNode(WKTConstants::UNIT, !codeSpace().empty());
+    } else if (!unitType.empty()) {
+        formatter->startNode(unitType, !codeSpace().empty());
+    } else {
+        if (isWKT2 && type() == Type::LINEAR) {
+            formatter->startNode(WKTConstants::LENGTHUNIT,
+                                 !codeSpace().empty());
+        } else if (isWKT2 && type() == Type::ANGULAR) {
+            formatter->startNode(WKTConstants::ANGLEUNIT, !codeSpace().empty());
+        } else if (isWKT2 && type() == Type::SCALE) {
+            formatter->startNode(WKTConstants::SCALEUNIT, !codeSpace().empty());
+        } else if (isWKT2 && type() == Type::TIME) {
+            formatter->startNode(WKTConstants::TIMEUNIT, !codeSpace().empty());
+        } else if (isWKT2 && type() == Type::PARAMETRIC) {
+            formatter->startNode(WKTConstants::PARAMETRICUNIT,
+                                 !codeSpace().empty());
+        } else {
+            formatter->startNode(WKTConstants::UNIT, !codeSpace().empty());
+        }
+    }
+
+    {
+        const auto &l_name = name();
+        const bool esri = formatter->useESRIDialect();
+        if (esri) {
+            if (ci_equal(l_name, "degree")) {
+                formatter->addQuotedString("Degree");
+            } else if (ci_equal(l_name, "grad")) {
+                formatter->addQuotedString("Grad");
+            } else if (ci_equal(l_name, "metre")) {
+                formatter->addQuotedString("Meter");
+            } else {
+                formatter->addQuotedString(l_name);
+            }
+        } else {
+            formatter->addQuotedString(l_name);
+        }
+        const auto &factor = conversionToSI();
+        if (!isWKT2 || factor != 0.0) {
+            // Some TIMEUNIT do not have a conversion factor
+            formatter->add(factor);
+        }
+        if (!codeSpace().empty() && formatter->outputId()) {
+            formatter->startNode(
+                isWKT2 ? WKTConstants::ID : WKTConstants::AUTHORITY, false);
+            formatter->addQuotedString(codeSpace());
+            const auto &l_code = code();
+            if (isWKT2) {
+                try {
+                    (void)std::stoi(l_code);
+                    formatter->add(l_code);
+                } catch (const std::exception &) {
+                    formatter->addQuotedString(l_code);
+                }
+            } else {
+                formatter->addQuotedString(l_code);
+            }
+            formatter->endNode();
+        }
+    }
+    formatter->endNode();
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** Returns whether two units of measures are equal.
+ *
+ * The comparison is based on the name.
+ */
+bool UnitOfMeasure::operator==(const UnitOfMeasure &other) PROJ_PURE_DEFN {
+    return name() == other.name();
+}
+
+// ---------------------------------------------------------------------------
+
+/** Returns whether two units of measures are different.
+ *
+ * The comparison is based on the name.
+ */
+bool UnitOfMeasure::operator!=(const UnitOfMeasure &other) PROJ_PURE_DEFN {
+    return name() != other.name();
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+std::string UnitOfMeasure::exportToPROJString() const {
+    if (type() == Type::LINEAR) {
+        auto proj_units = proj_list_units();
+        for (int i = 0; proj_units[i].id != nullptr; i++) {
+            if (::fabs(proj_units[i].factor - conversionToSI()) <
+                1e-10 * conversionToSI()) {
+                return proj_units[i].id;
+            }
+        }
+    } else if (type() == Type::ANGULAR) {
+        auto proj_angular_units = proj_list_angular_units();
+        for (int i = 0; proj_angular_units[i].id != nullptr; i++) {
+            if (::fabs(proj_angular_units[i].factor - conversionToSI()) <
+                1e-10 * conversionToSI()) {
+                return proj_angular_units[i].id;
+            }
+        }
+    }
+    return std::string();
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+bool UnitOfMeasure::_isEquivalentTo(
+    const UnitOfMeasure &other, util::IComparable::Criterion criterion) const {
+    if (criterion == util::IComparable::Criterion::STRICT) {
+        return operator==(other);
+    }
+    return std::fabs(conversionToSI() - other.conversionToSI()) <=
+           1e-10 * std::fabs(conversionToSI());
+}
+
+//! @endcond
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct Measure::Private {
+    double value_ = 0.0;
+    UnitOfMeasure unit_{};
+
+    Private(double valueIn, const UnitOfMeasure &unitIn)
+        : value_(valueIn), unit_(unitIn) {}
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a Measure.
+ */
+Measure::Measure(double valueIn, const UnitOfMeasure &unitIn)
+    : d(internal::make_unique<Private>(valueIn, unitIn)) {}
+
+// ---------------------------------------------------------------------------
+
+Measure::Measure(const Measure &other)
+    : d(internal::make_unique<Private>(*(other.d))) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+Measure::~Measure() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the unit of the Measure.
+ */
+const UnitOfMeasure &Measure::unit() PROJ_CONST_DEFN { return d->unit_; }
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the value of the Measure, after conversion to the
+ * corresponding
+ * unit of the International System.
+ */
+double Measure::getSIValue() PROJ_CONST_DEFN {
+    return d->value_ * d->unit_.conversionToSI();
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the value of the measure, expressed in the unit()
+ */
+double Measure::value() PROJ_CONST_DEFN { return d->value_; }
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the value of this measure expressed into the provided unit.
+ */
+double Measure::convertToUnit(const UnitOfMeasure &otherUnit) PROJ_CONST_DEFN {
+    return getSIValue() / otherUnit.conversionToSI();
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return whether two measures are equal.
+ *
+ * The comparison is done both on the value and the unit.
+ */
+bool Measure::operator==(const Measure &other) PROJ_CONST_DEFN {
+    return d->value_ == other.d->value_ && d->unit_ == other.d->unit_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns whether an object is equivalent to another one.
+ * @param other other object to compare to
+ * @param criterion comparaison criterion.
+ * @param maxRelativeError Maximum relative error allowed.
+ * @return true if objects are equivalent.
+ */
+bool Measure::_isEquivalentTo(const Measure &other,
+                              util::IComparable::Criterion criterion,
+                              double maxRelativeError) const {
+    if (criterion == util::IComparable::Criterion::STRICT) {
+        return operator==(other);
+    }
+    return std::fabs(getSIValue() - other.getSIValue()) <=
+           maxRelativeError * std::fabs(getSIValue());
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a Scale.
+ *
+ * @param valueIn value
+ */
+Scale::Scale(double valueIn) : Measure(valueIn, UnitOfMeasure::SCALE_UNITY) {}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a Scale.
+ *
+ * @param valueIn value
+ * @param unitIn unit. Constraint: unit.type() == UnitOfMeasure::Type::SCALE
+ */
+Scale::Scale(double valueIn, const UnitOfMeasure &unitIn)
+    : Measure(valueIn, unitIn) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+Scale::Scale(const Scale &) = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+Scale::~Scale() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a Angle.
+ *
+ * @param valueIn value
+ */
+Angle::Angle(double valueIn) : Measure(valueIn, UnitOfMeasure::DEGREE) {}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a Angle.
+ *
+ * @param valueIn value
+ * @param unitIn unit. Constraint: unit.type() == UnitOfMeasure::Type::ANGULAR
+ */
+Angle::Angle(double valueIn, const UnitOfMeasure &unitIn)
+    : Measure(valueIn, unitIn) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+Angle::Angle(const Angle &) = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+Angle::~Angle() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a Length.
+ *
+ * @param valueIn value
+ */
+Length::Length(double valueIn) : Measure(valueIn, UnitOfMeasure::METRE) {}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a Length.
+ *
+ * @param valueIn value
+ * @param unitIn unit. Constraint: unit.type() == UnitOfMeasure::Type::LINEAR
+ */
+Length::Length(double valueIn, const UnitOfMeasure &unitIn)
+    : Measure(valueIn, unitIn) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+Length::Length(const Length &) = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+Length::~Length() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct DateTime::Private {
+    std::string str_{};
+
+    explicit Private(const std::string &str) : str_(str) {}
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+DateTime::DateTime() : d(internal::make_unique<Private>(std::string())) {}
+
+// ---------------------------------------------------------------------------
+
+DateTime::DateTime(const std::string &str)
+    : d(internal::make_unique<Private>(str)) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+DateTime::DateTime(const DateTime &other)
+    : d(internal::make_unique<Private>(*(other.d))) {}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+DateTime::~DateTime() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a DateTime. */
+DateTime DateTime::create(const std::string &str) { return DateTime(str); }
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return whether the DateTime is ISO:8601 compliant.
+ *
+ * \remark The current implementation is really simplistic, and aimed at
+ * detecting date-times that are not ISO:8601 compliant.
+ */
+bool DateTime::isISO_8601() const {
+    return !d->str_.empty() && d->str_[0] >= '0' && d->str_[0] <= '9' &&
+           d->str_.find(' ') == std::string::npos;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the DateTime as a string.
+ */
+std::string DateTime::toString() const { return d->str_; }
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+// cppcheck-suppress copyCtorAndEqOperator
+struct IdentifiedObject::Private {
+    IdentifierNNPtr name{Identifier::create()};
+    std::vector<IdentifierNNPtr> identifiers{};
+    std::vector<GenericNameNNPtr> aliases{};
+    std::string remarks{};
+    bool isDeprecated{};
+
+    void setIdentifiers(const PropertyMap &properties);
+    void setName(const PropertyMap &properties);
+    void setAliases(const PropertyMap &properties);
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+IdentifiedObject::IdentifiedObject() : d(internal::make_unique<Private>()) {}
+
+// ---------------------------------------------------------------------------
+
+IdentifiedObject::IdentifiedObject(const IdentifiedObject &other)
+    : d(internal::make_unique<Private>(*(other.d))) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+IdentifiedObject::~IdentifiedObject() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the name of the object.
+ *
+ * Generally, the only interesting field of the name will be
+ * name()->description().
+ */
+const IdentifierNNPtr &IdentifiedObject::name() PROJ_CONST_DEFN {
+    return d->name;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the name of the object.
+ *
+ * Return *(name()->description())
+ */
+const std::string &IdentifiedObject::nameStr() PROJ_CONST_DEFN {
+    return *(d->name->description());
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the identifier(s) of the object
+ *
+ * Generally, those will have Identifier::code() and Identifier::codeSpace()
+ * filled.
+ */
+const std::vector<IdentifierNNPtr> &
+IdentifiedObject::identifiers() PROJ_CONST_DEFN {
+    return d->identifiers;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the alias(es) of the object.
+ */
+const std::vector<GenericNameNNPtr> &
+IdentifiedObject::aliases() PROJ_CONST_DEFN {
+    return d->aliases;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the (first) alias of the object as a string.
+ *
+ * Shortcut for aliases()[0]->toFullyQualifiedName()->toString()
+ */
+std::string IdentifiedObject::alias() PROJ_CONST_DEFN {
+    if (d->aliases.empty())
+        return std::string();
+    return d->aliases[0]->toFullyQualifiedName()->toString();
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the EPSG code.
+ * @return code, or 0 if not found
+ */
+int IdentifiedObject::getEPSGCode() PROJ_CONST_DEFN {
+    for (const auto &id : identifiers()) {
+        if (ci_equal(*(id->codeSpace()), metadata::Identifier::EPSG)) {
+            return ::atoi(id->code().c_str());
+        }
+    }
+    return 0;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the remarks.
+ */
+const std::string &IdentifiedObject::remarks() PROJ_CONST_DEFN {
+    return d->remarks;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return whether the object is deprecated.
+ *
+ * \remark Extension of \ref ISO_19111_2018
+ */
+bool IdentifiedObject::isDeprecated() PROJ_CONST_DEFN {
+    return d->isDeprecated;
+}
+
+// ---------------------------------------------------------------------------
+//! @cond Doxygen_Suppress
+
+void IdentifiedObject::Private::setName(
+    const PropertyMap &properties) // throw(InvalidValueTypeException)
+{
+    const auto pVal = properties.get(NAME_KEY);
+    if (!pVal) {
+        return;
+    }
+    if (const auto genVal = dynamic_cast<const BoxedValue *>(pVal->get())) {
+        if (genVal->type() == BoxedValue::Type::STRING) {
+            name = Identifier::createFromDescription(genVal->stringValue());
+        } else {
+            throw InvalidValueTypeException("Invalid value type for " +
+                                            NAME_KEY);
+        }
+    } else {
+        if (auto identifier =
+                util::nn_dynamic_pointer_cast<Identifier>(*pVal)) {
+            name = NN_NO_CHECK(identifier);
+        } else {
+            throw InvalidValueTypeException("Invalid value type for " +
+                                            NAME_KEY);
+        }
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+void IdentifiedObject::Private::setIdentifiers(
+    const PropertyMap &properties) // throw(InvalidValueTypeException)
+{
+    auto pVal = properties.get(IDENTIFIERS_KEY);
+    if (!pVal) {
+
+        pVal = properties.get(Identifier::CODE_KEY);
+        if (pVal) {
+            identifiers.push_back(
+                Identifier::create(std::string(), properties));
+        }
+        return;
+    }
+    if (auto identifier = util::nn_dynamic_pointer_cast<Identifier>(*pVal)) {
+        identifiers.clear();
+        identifiers.push_back(NN_NO_CHECK(identifier));
+    } else {
+        if (auto array = dynamic_cast<const ArrayOfBaseObject *>(pVal->get())) {
+            identifiers.clear();
+            for (const auto &val : *array) {
+                identifier = util::nn_dynamic_pointer_cast<Identifier>(val);
+                if (identifier) {
+                    identifiers.push_back(NN_NO_CHECK(identifier));
+                } else {
+                    throw InvalidValueTypeException("Invalid value type for " +
+                                                    IDENTIFIERS_KEY);
+                }
+            }
+        } else {
+            throw InvalidValueTypeException("Invalid value type for " +
+                                            IDENTIFIERS_KEY);
+        }
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+void IdentifiedObject::Private::setAliases(
+    const PropertyMap &properties) // throw(InvalidValueTypeException)
+{
+    const auto pVal = properties.get(ALIAS_KEY);
+    if (!pVal) {
+        return;
+    }
+    if (auto l_name = util::nn_dynamic_pointer_cast<GenericName>(*pVal)) {
+        aliases.clear();
+        aliases.push_back(NN_NO_CHECK(l_name));
+    } else {
+        if (const auto array =
+                dynamic_cast<const ArrayOfBaseObject *>(pVal->get())) {
+            aliases.clear();
+            for (const auto &val : *array) {
+                l_name = util::nn_dynamic_pointer_cast<GenericName>(val);
+                if (l_name) {
+                    aliases.push_back(NN_NO_CHECK(l_name));
+                } else {
+                    if (auto genVal =
+                            dynamic_cast<const BoxedValue *>(val.get())) {
+                        if (genVal->type() == BoxedValue::Type::STRING) {
+                            aliases.push_back(NameFactory::createLocalName(
+                                nullptr, genVal->stringValue()));
+                        } else {
+                            throw InvalidValueTypeException(
+                                "Invalid value type for " + ALIAS_KEY);
+                        }
+                    } else {
+                        throw InvalidValueTypeException(
+                            "Invalid value type for " + ALIAS_KEY);
+                    }
+                }
+            }
+        } else {
+            std::string temp;
+            if (properties.getStringValue(ALIAS_KEY, temp)) {
+                aliases.clear();
+                aliases.push_back(NameFactory::createLocalName(nullptr, temp));
+            } else {
+                throw InvalidValueTypeException("Invalid value type for " +
+                                                ALIAS_KEY);
+            }
+        }
+    }
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+void IdentifiedObject::setProperties(
+    const PropertyMap &properties) // throw(InvalidValueTypeException)
+{
+    d->setName(properties);
+    d->setIdentifiers(properties);
+    d->setAliases(properties);
+
+    properties.getStringValue(REMARKS_KEY, d->remarks);
+
+    {
+        const auto pVal = properties.get(DEPRECATED_KEY);
+        if (pVal) {
+            if (const auto genVal =
+                    dynamic_cast<const BoxedValue *>(pVal->get())) {
+                if (genVal->type() == BoxedValue::Type::BOOLEAN) {
+                    d->isDeprecated = genVal->booleanValue();
+                } else {
+                    throw InvalidValueTypeException("Invalid value type for " +
+                                                    DEPRECATED_KEY);
+                }
+            } else {
+                throw InvalidValueTypeException("Invalid value type for " +
+                                                DEPRECATED_KEY);
+            }
+        }
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void IdentifiedObject::formatID(WKTFormatter *formatter) const {
+    const bool isWKT2 = formatter->version() == WKTFormatter::Version::WKT2;
+    for (const auto &id : identifiers()) {
+        id->_exportToWKT(formatter);
+        if (!isWKT2) {
+            break;
+        }
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+void IdentifiedObject::formatRemarks(WKTFormatter *formatter) const {
+    if (!remarks().empty()) {
+        formatter->startNode(WKTConstants::REMARK, false);
+        formatter->addQuotedString(remarks());
+        formatter->endNode();
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+bool IdentifiedObject::_isEquivalentTo(
+    const util::IComparable *other,
+    util::IComparable::Criterion criterion) const {
+    auto otherIdObj = dynamic_cast<const IdentifiedObject *>(other);
+    if (!otherIdObj)
+        return false;
+    return _isEquivalentTo(otherIdObj, criterion);
+}
+
+// ---------------------------------------------------------------------------
+
+bool IdentifiedObject::_isEquivalentTo(const IdentifiedObject *otherIdObj,
+                                       util::IComparable::Criterion criterion)
+    PROJ_CONST_DEFN {
+    if (criterion == util::IComparable::Criterion::STRICT) {
+        if (!ci_equal(nameStr(), otherIdObj->nameStr())) {
+            return false;
+        }
+        // TODO test id etc
+    } else {
+        if (!metadata::Identifier::isEquivalentName(
+                nameStr().c_str(), otherIdObj->nameStr().c_str())) {
+            return false;
+        }
+    }
+    return true;
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct ObjectDomain::Private {
+    optional<std::string> scope_{};
+    ExtentPtr domainOfValidity_{};
+
+    Private(const optional<std::string> &scopeIn, const ExtentPtr &extent)
+        : scope_(scopeIn), domainOfValidity_(extent) {}
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+ObjectDomain::ObjectDomain(const optional<std::string> &scopeIn,
+                           const ExtentPtr &extent)
+    : d(internal::make_unique<Private>(scopeIn, extent)) {}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+ObjectDomain::ObjectDomain(const ObjectDomain &other)
+    : d(internal::make_unique<Private>(*(other.d))) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+ObjectDomain::~ObjectDomain() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the scope.
+ *
+ * @return the scope, or empty.
+ */
+const optional<std::string> &ObjectDomain::scope() PROJ_CONST_DEFN {
+    return d->scope_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the domain of validity.
+ *
+ * @return the domain of validity, or nullptr.
+ */
+const ExtentPtr &ObjectDomain::domainOfValidity() PROJ_CONST_DEFN {
+    return d->domainOfValidity_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ObjectDomain.
+ */
+ObjectDomainNNPtr ObjectDomain::create(const optional<std::string> &scopeIn,
+                                       const ExtentPtr &extent) {
+    return ObjectDomain::nn_make_shared<ObjectDomain>(scopeIn, extent);
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void ObjectDomain::_exportToWKT(WKTFormatter *formatter) const {
+    if (d->scope_.has_value()) {
+        formatter->startNode(WKTConstants::SCOPE, false);
+        formatter->addQuotedString(*(d->scope_));
+        formatter->endNode();
+    } else if (formatter->use2018Keywords()) {
+        formatter->startNode(WKTConstants::SCOPE, false);
+        formatter->addQuotedString("unknown");
+        formatter->endNode();
+    }
+    if (d->domainOfValidity_) {
+        if (d->domainOfValidity_->description().has_value()) {
+            formatter->startNode(WKTConstants::AREA, false);
+            formatter->addQuotedString(*(d->domainOfValidity_->description()));
+            formatter->endNode();
+        }
+        if (d->domainOfValidity_->geographicElements().size() == 1) {
+            const auto bbox = dynamic_cast<const GeographicBoundingBox *>(
+                d->domainOfValidity_->geographicElements()[0].get());
+            if (bbox) {
+                formatter->startNode(WKTConstants::BBOX, false);
+                formatter->add(bbox->southBoundLatitude());
+                formatter->add(bbox->westBoundLongitude());
+                formatter->add(bbox->northBoundLatitude());
+                formatter->add(bbox->eastBoundLongitude());
+                formatter->endNode();
+            }
+        }
+        if (d->domainOfValidity_->verticalElements().size() == 1) {
+            auto extent = d->domainOfValidity_->verticalElements()[0];
+            formatter->startNode(WKTConstants::VERTICALEXTENT, false);
+            formatter->add(extent->minimumValue());
+            formatter->add(extent->maximumValue());
+            extent->unit()->_exportToWKT(formatter);
+            formatter->endNode();
+        }
+        if (d->domainOfValidity_->temporalElements().size() == 1) {
+            auto extent = d->domainOfValidity_->temporalElements()[0];
+            formatter->startNode(WKTConstants::TIMEEXTENT, false);
+            if (DateTime::create(extent->start()).isISO_8601()) {
+                formatter->add(extent->start());
+            } else {
+                formatter->addQuotedString(extent->start());
+            }
+            if (DateTime::create(extent->stop()).isISO_8601()) {
+                formatter->add(extent->stop());
+            } else {
+                formatter->addQuotedString(extent->stop());
+            }
+            formatter->endNode();
+        }
+    }
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+bool ObjectDomain::_isEquivalentTo(
+    const util::IComparable *other,
+    util::IComparable::Criterion criterion) const {
+    auto otherDomain = dynamic_cast<const ObjectDomain *>(other);
+    if (!otherDomain)
+        return false;
+    if (scope().has_value() != otherDomain->scope().has_value())
+        return false;
+    if (*scope() != *otherDomain->scope())
+        return false;
+    if ((domainOfValidity().get() != nullptr) ^
+        (otherDomain->domainOfValidity().get() != nullptr))
+        return false;
+    return domainOfValidity().get() == nullptr ||
+           domainOfValidity()->_isEquivalentTo(
+               otherDomain->domainOfValidity().get(), criterion);
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct ObjectUsage::Private {
+    std::vector<ObjectDomainNNPtr> domains_{};
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+ObjectUsage::ObjectUsage() : d(internal::make_unique<Private>()) {}
+
+// ---------------------------------------------------------------------------
+
+ObjectUsage::ObjectUsage(const ObjectUsage &other)
+    : IdentifiedObject(other), d(internal::make_unique<Private>(*(other.d))) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+ObjectUsage::~ObjectUsage() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the domains of the object.
+ */
+const std::vector<ObjectDomainNNPtr> &ObjectUsage::domains() PROJ_CONST_DEFN {
+    return d->domains_;
+}
+
+// ---------------------------------------------------------------------------
+
+void ObjectUsage::setProperties(
+    const PropertyMap &properties) // throw(InvalidValueTypeException)
+{
+    IdentifiedObject::setProperties(properties);
+
+    optional<std::string> scope;
+    properties.getStringValue(SCOPE_KEY, scope);
+
+    ExtentPtr domainOfValidity;
+    {
+        const auto pVal = properties.get(DOMAIN_OF_VALIDITY_KEY);
+        if (pVal) {
+            domainOfValidity = util::nn_dynamic_pointer_cast<Extent>(*pVal);
+            if (!domainOfValidity) {
+                throw InvalidValueTypeException("Invalid value type for " +
+                                                DOMAIN_OF_VALIDITY_KEY);
+            }
+        }
+    }
+
+    if (scope.has_value() || domainOfValidity) {
+        d->domains_.emplace_back(ObjectDomain::create(scope, domainOfValidity));
+    }
+
+    {
+        const auto pVal = properties.get(OBJECT_DOMAIN_KEY);
+        if (pVal) {
+            if (auto objectDomain =
+                    util::nn_dynamic_pointer_cast<ObjectDomain>(*pVal)) {
+                d->domains_.emplace_back(NN_NO_CHECK(objectDomain));
+            } else if (const auto array =
+                           dynamic_cast<const ArrayOfBaseObject *>(
+                               pVal->get())) {
+                for (const auto &val : *array) {
+                    objectDomain =
+                        util::nn_dynamic_pointer_cast<ObjectDomain>(val);
+                    if (objectDomain) {
+                        d->domains_.emplace_back(NN_NO_CHECK(objectDomain));
+                    } else {
+                        throw InvalidValueTypeException(
+                            "Invalid value type for " + OBJECT_DOMAIN_KEY);
+                    }
+                }
+            } else {
+                throw InvalidValueTypeException("Invalid value type for " +
+                                                OBJECT_DOMAIN_KEY);
+            }
+        }
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+void ObjectUsage::baseExportToWKT(WKTFormatter *formatter) const {
+    const bool isWKT2 = formatter->version() == WKTFormatter::Version::WKT2;
+    if (isWKT2 && formatter->outputId()) {
+        auto l_domains = domains();
+        if (!l_domains.empty()) {
+            if (formatter->use2018Keywords()) {
+                for (const auto &domain : l_domains) {
+                    formatter->startNode(WKTConstants::USAGE, false);
+                    domain->_exportToWKT(formatter);
+                    formatter->endNode();
+                }
+            } else {
+                l_domains[0]->_exportToWKT(formatter);
+            }
+        }
+    }
+    if (formatter->outputId()) {
+        formatID(formatter);
+    }
+    if (isWKT2) {
+        formatRemarks(formatter);
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+bool ObjectUsage::_isEquivalentTo(
+    const util::IComparable *other,
+    util::IComparable::Criterion criterion) const {
+    auto otherObjUsage = dynamic_cast<const ObjectUsage *>(other);
+    if (!otherObjUsage)
+        return false;
+
+    // TODO: incomplete
+    return IdentifiedObject::_isEquivalentTo(other, criterion);
+}
+//! @endcond
+
+} // namespace common
+NS_PROJ_END
diff --git a/src/iso19111/coordinateoperation.cpp b/src/iso19111/coordinateoperation.cpp
new file mode 100644
index 00000000..442a9b78
--- /dev/null
+++ b/src/iso19111/coordinateoperation.cpp
@@ -0,0 +1,11749 @@
+/******************************************************************************
+ *
+ * Project:  PROJ
+ * Purpose:  ISO19111:2018 implementation
+ * Author:   Even Rouault <even dot rouault at spatialys dot com>
+ *
+ ******************************************************************************
+ * Copyright (c) 2018, Even Rouault <even dot rouault at spatialys dot com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ ****************************************************************************/
+
+#ifndef FROM_PROJ_CPP
+#define FROM_PROJ_CPP
+#endif
+#define FROM_COORDINATE_OPERATION_CPP
+
+#include "proj/coordinateoperation.hpp"
+#include "proj/common.hpp"
+#include "proj/crs.hpp"
+#include "proj/io.hpp"
+#include "proj/metadata.hpp"
+#include "proj/util.hpp"
+
+#include "proj/internal/internal.hpp"
+#include "proj/internal/io_internal.hpp"
+
+#include "projects.h" // M_PI
+
+#include <algorithm>
+#include <cassert>
+#include <cmath>
+#include <cstring>
+#include <memory>
+#include <set>
+#include <string>
+#include <vector>
+
+using namespace NS_PROJ::internal;
+
+#if 0
+namespace dropbox{ namespace oxygen {
+template<> nn<NS_PROJ::operation::CoordinateOperationPtr>::~nn() = default;
+template<> nn<NS_PROJ::operation::SingleOperationPtr>::~nn() = default;
+template<> nn<NS_PROJ::operation::ConversionPtr>::~nn() = default;
+template<> nn<NS_PROJ::operation::TransformationPtr>::~nn() = default;
+template<> nn<NS_PROJ::operation::ConcatenatedOperationPtr>::~nn() = default;
+template<> nn<NS_PROJ::operation::PointMotionOperationPtr>::~nn() = default;
+template<> nn<NS_PROJ::operation::GeneralOperationParameterPtr>::~nn() = default;
+template<> nn<NS_PROJ::operation::OperationParameterPtr>::~nn() = default;
+template<> nn<NS_PROJ::operation::GeneralParameterValuePtr>::~nn() = default;
+template<> nn<NS_PROJ::operation::ParameterValuePtr>::~nn() = default;
+template<> nn<NS_PROJ::operation::OperationMethodPtr>::~nn() = default;
+template<> nn<NS_PROJ::operation::OperationParameterValuePtr>::~nn() = default;
+template<> nn<std::unique_ptr<NS_PROJ::operation::CoordinateOperationFactory, std::default_delete<NS_PROJ::operation::CoordinateOperationFactory> > >::~nn() = default;
+template<> nn<std::unique_ptr<NS_PROJ::operation::CoordinateOperationContext, std::default_delete<NS_PROJ::operation::CoordinateOperationContext> > >::~nn() = default;
+}}
+#endif
+
+#include "proj/internal/coordinateoperation_constants.hpp"
+#include "proj/internal/coordinateoperation_internal.hpp"
+#include "proj/internal/esri_projection_mappings.hpp"
+
+#if 0
+namespace dropbox{ namespace oxygen {
+template<> nn<std::shared_ptr<NS_PROJ::operation::InverseCoordinateOperation>>::~nn() = default;
+template<> nn<std::shared_ptr<NS_PROJ::operation::InverseConversion>>::~nn() = default;
+template<> nn<std::shared_ptr<NS_PROJ::operation::InverseTransformation>>::~nn() = default;
+template<> nn<NS_PROJ::operation::PROJBasedOperationPtr>::~nn() = default;
+}}
+#endif
+
+// ---------------------------------------------------------------------------
+
+NS_PROJ_START
+namespace operation {
+
+//! @cond Doxygen_Suppress
+
+constexpr double UTM_LATITUDE_OF_NATURAL_ORIGIN = 0.0;
+constexpr double UTM_SCALE_FACTOR = 0.9996;
+constexpr double UTM_FALSE_EASTING = 500000.0;
+constexpr double UTM_NORTH_FALSE_NORTHING = 0.0;
+constexpr double UTM_SOUTH_FALSE_NORTHING = 10000000.0;
+
+static const std::string INVERSE_OF = "Inverse of ";
+static const char *NULL_GEOCENTRIC_TRANSLATION = "Null geocentric translation";
+static const char *NULL_GEOGRAPHIC_OFFSET = "Null geographic offset";
+//! @endcond
+
+//! @cond Doxygen_Suppress
+static util::PropertyMap
+createPropertiesForInverse(const CoordinateOperation *op, bool derivedFrom,
+                           bool approximateInversion);
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+class InvalidOperationEmptyIntersection : public InvalidOperation {
+  public:
+    explicit InvalidOperationEmptyIntersection(const std::string &message);
+    InvalidOperationEmptyIntersection(
+        const InvalidOperationEmptyIntersection &other);
+    ~InvalidOperationEmptyIntersection() override;
+};
+
+InvalidOperationEmptyIntersection::InvalidOperationEmptyIntersection(
+    const std::string &message)
+    : InvalidOperation(message) {}
+
+InvalidOperationEmptyIntersection::InvalidOperationEmptyIntersection(
+    const InvalidOperationEmptyIntersection &) = default;
+
+InvalidOperationEmptyIntersection::~InvalidOperationEmptyIntersection() =
+    default;
+
+// ---------------------------------------------------------------------------
+
+static std::string createEntryEqParam(const std::string &a,
+                                      const std::string &b) {
+    return a < b ? a + b : b + a;
+}
+
+static std::set<std::string> buildSetEquivalentParameters() {
+
+    std::set<std::string> set;
+
+    const char *const listOfEquivalentParameterNames[][7] = {
+        {"latitude_of_point_1", "Latitude_Of_1st_Point", nullptr},
+        {"longitude_of_point_1", "Longitude_Of_1st_Point", nullptr},
+        {"latitude_of_point_2", "Latitude_Of_2nd_Point", nullptr},
+        {"longitude_of_point_2", "Longitude_Of_2nd_Point", nullptr},
+
+        {"satellite_height", "height", nullptr},
+
+        {EPSG_NAME_PARAMETER_FALSE_EASTING,
+         EPSG_NAME_PARAMETER_EASTING_FALSE_ORIGIN,
+         EPSG_NAME_PARAMETER_EASTING_PROJECTION_CENTRE, nullptr},
+
+        {EPSG_NAME_PARAMETER_FALSE_NORTHING,
+         EPSG_NAME_PARAMETER_NORTHING_FALSE_ORIGIN,
+         EPSG_NAME_PARAMETER_NORTHING_PROJECTION_CENTRE, nullptr},
+
+        {EPSG_NAME_PARAMETER_SCALE_FACTOR_AT_NATURAL_ORIGIN, WKT1_SCALE_FACTOR,
+         EPSG_NAME_PARAMETER_SCALE_FACTOR_INITIAL_LINE,
+         EPSG_NAME_PARAMETER_SCALE_FACTOR_PSEUDO_STANDARD_PARALLEL, nullptr},
+
+        {WKT1_LATITUDE_OF_ORIGIN, WKT1_LATITUDE_OF_CENTER,
+         EPSG_NAME_PARAMETER_LATITUDE_OF_NATURAL_ORIGIN,
+         EPSG_NAME_PARAMETER_LATITUDE_FALSE_ORIGIN,
+         EPSG_NAME_PARAMETER_LATITUDE_PROJECTION_CENTRE, "Central_Parallel",
+         nullptr},
+
+        {WKT1_CENTRAL_MERIDIAN, WKT1_LONGITUDE_OF_CENTER,
+         EPSG_NAME_PARAMETER_LONGITUDE_OF_NATURAL_ORIGIN,
+         EPSG_NAME_PARAMETER_LONGITUDE_FALSE_ORIGIN,
+         EPSG_NAME_PARAMETER_LONGITUDE_PROJECTION_CENTRE,
+         EPSG_NAME_PARAMETER_LONGITUDE_OF_ORIGIN, nullptr},
+
+        {"pseudo_standard_parallel_1", WKT1_STANDARD_PARALLEL_1, nullptr},
+    };
+
+    for (const auto &paramList : listOfEquivalentParameterNames) {
+        for (size_t i = 0; paramList[i]; i++) {
+            auto a = metadata::Identifier::canonicalizeName(paramList[i]);
+            for (size_t j = i + 1; paramList[j]; j++) {
+                auto b = metadata::Identifier::canonicalizeName(paramList[j]);
+                set.insert(createEntryEqParam(a, b));
+            }
+        }
+    }
+    return set;
+}
+
+bool areEquivalentParameters(const std::string &a, const std::string &b) {
+
+    static const std::set<std::string> setEquivalentParameters =
+        buildSetEquivalentParameters();
+
+    auto a_can = metadata::Identifier::canonicalizeName(a);
+    auto b_can = metadata::Identifier::canonicalizeName(b);
+    return setEquivalentParameters.find(createEntryEqParam(a_can, b_can)) !=
+           setEquivalentParameters.end();
+}
+
+// ---------------------------------------------------------------------------
+
+PROJ_NO_INLINE const MethodMapping *getMapping(int epsg_code) noexcept {
+    for (const auto &mapping : projectionMethodMappings) {
+        if (mapping.epsg_code == epsg_code) {
+            return &mapping;
+        }
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+const MethodMapping *getMapping(const OperationMethod *method) noexcept {
+    const std::string &name(method->nameStr());
+    const int epsg_code = method->getEPSGCode();
+    for (const auto &mapping : projectionMethodMappings) {
+        if ((epsg_code != 0 && mapping.epsg_code == epsg_code) ||
+            metadata::Identifier::isEquivalentName(mapping.wkt2_name,
+                                                   name.c_str())) {
+            return &mapping;
+        }
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+const MethodMapping *getMappingFromWKT1(const std::string &wkt1_name) noexcept {
+    // Unusual for a WKT1 projection name, but mentionned in OGC 12-063r5 C.4.2
+    if (ci_starts_with(wkt1_name, "UTM zone")) {
+        return getMapping(EPSG_CODE_METHOD_TRANSVERSE_MERCATOR);
+    }
+
+    for (const auto &mapping : projectionMethodMappings) {
+        if (mapping.wkt1_name && metadata::Identifier::isEquivalentName(
+                                     mapping.wkt1_name, wkt1_name.c_str())) {
+            return &mapping;
+        }
+    }
+    return nullptr;
+}
+// ---------------------------------------------------------------------------
+
+const MethodMapping *getMapping(const char *wkt2_name) noexcept {
+    for (const auto &mapping : projectionMethodMappings) {
+        if (metadata::Identifier::isEquivalentName(mapping.wkt2_name,
+                                                   wkt2_name)) {
+            return &mapping;
+        }
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+std::vector<const MethodMapping *>
+getMappingsFromPROJName(const std::string &projName) {
+    std::vector<const MethodMapping *> res;
+    for (const auto &mapping : projectionMethodMappings) {
+        if (mapping.proj_name_main && projName == mapping.proj_name_main) {
+            res.push_back(&mapping);
+        }
+    }
+    return res;
+}
+
+// ---------------------------------------------------------------------------
+
+static const ParamMapping *getMapping(const MethodMapping *mapping,
+                                      const OperationParameterNNPtr &param) {
+    if (mapping->params == nullptr) {
+        return nullptr;
+    }
+
+    // First try with id
+    const int epsg_code = param->getEPSGCode();
+    if (epsg_code) {
+        for (int i = 0; mapping->params[i] != nullptr; ++i) {
+            const auto *paramMapping = mapping->params[i];
+            if (paramMapping->epsg_code == epsg_code) {
+                return paramMapping;
+            }
+        }
+    }
+
+    // then equivalent name
+    const std::string &name = param->nameStr();
+    for (int i = 0; mapping->params[i] != nullptr; ++i) {
+        const auto *paramMapping = mapping->params[i];
+        if (metadata::Identifier::isEquivalentName(paramMapping->wkt2_name,
+                                                   name.c_str())) {
+            return paramMapping;
+        }
+    }
+
+    // and finally different name, but equivalent parameter
+    for (int i = 0; mapping->params[i] != nullptr; ++i) {
+        const auto *paramMapping = mapping->params[i];
+        if (areEquivalentParameters(paramMapping->wkt2_name, name)) {
+            return paramMapping;
+        }
+    }
+
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+const ParamMapping *getMappingFromWKT1(const MethodMapping *mapping,
+                                       const std::string &wkt1_name) {
+    for (int i = 0; mapping->params[i] != nullptr; ++i) {
+        const auto *paramMapping = mapping->params[i];
+        if (paramMapping->wkt1_name &&
+            (metadata::Identifier::isEquivalentName(paramMapping->wkt1_name,
+                                                    wkt1_name.c_str()) ||
+             areEquivalentParameters(paramMapping->wkt1_name, wkt1_name))) {
+            return paramMapping;
+        }
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+std::vector<const ESRIMethodMapping *>
+getMappingsFromESRI(const std::string &esri_name) {
+    std::vector<const ESRIMethodMapping *> res;
+    for (const auto &mapping : esriMappings) {
+        if (ci_equal(esri_name, mapping.esri_name)) {
+            res.push_back(&mapping);
+        }
+    }
+    return res;
+}
+
+// ---------------------------------------------------------------------------
+
+static const ESRIMethodMapping *getESRIMapping(const std::string &wkt2_name,
+                                               int epsg_code) {
+    for (const auto &mapping : esriMappings) {
+        if ((epsg_code != 0 && mapping.epsg_code == epsg_code) ||
+            ci_equal(wkt2_name, mapping.wkt2_name)) {
+            return &mapping;
+        }
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+static double getAccuracy(const std::vector<CoordinateOperationNNPtr> &ops);
+
+// Returns the accuracy of an operation, or -1 if unknown
+static double getAccuracy(const CoordinateOperationNNPtr &op) {
+
+    if (dynamic_cast<const Conversion *>(op.get())) {
+        // A conversion is perfectly accurate.
+        return 0.0;
+    }
+
+    double accuracy = -1.0;
+    const auto &accuracies = op->coordinateOperationAccuracies();
+    if (!accuracies.empty()) {
+        try {
+            accuracy = c_locale_stod(accuracies[0]->value());
+        } catch (const std::exception &) {
+        }
+    } else {
+        auto concatenated =
+            dynamic_cast<const ConcatenatedOperation *>(op.get());
+        if (concatenated) {
+            accuracy = getAccuracy(concatenated->operations());
+        }
+    }
+    return accuracy;
+}
+
+// ---------------------------------------------------------------------------
+
+// Returns the accuracy of a set of concantenated operations, or -1 if unknown
+static double getAccuracy(const std::vector<CoordinateOperationNNPtr> &ops) {
+    double accuracy = -1.0;
+    for (const auto &subop : ops) {
+        const double subops_accuracy = getAccuracy(subop);
+        if (subops_accuracy < 0.0) {
+            return -1.0;
+        }
+        if (accuracy < 0.0) {
+            accuracy = 0.0;
+        }
+        accuracy += subops_accuracy;
+    }
+    return accuracy;
+}
+
+// ---------------------------------------------------------------------------
+
+static metadata::ExtentPtr
+getExtent(const std::vector<CoordinateOperationNNPtr> &ops,
+          bool conversionExtentIsWorld, bool &emptyIntersection);
+
+static metadata::ExtentPtr getExtent(const CoordinateOperationNNPtr &op,
+                                     bool conversionExtentIsWorld,
+                                     bool &emptyIntersection) {
+    auto conv = dynamic_cast<const Conversion *>(op.get());
+    if (conv) {
+        emptyIntersection = false;
+        return metadata::Extent::WORLD;
+    }
+    const auto &domains = op->domains();
+    if (!domains.empty()) {
+        emptyIntersection = false;
+        return domains[0]->domainOfValidity();
+    }
+    auto concatenated = dynamic_cast<const ConcatenatedOperation *>(op.get());
+    if (!concatenated) {
+        emptyIntersection = false;
+        return nullptr;
+    }
+    return getExtent(concatenated->operations(), conversionExtentIsWorld,
+                     emptyIntersection);
+}
+
+// ---------------------------------------------------------------------------
+
+static const metadata::ExtentPtr nullExtent{};
+
+static const metadata::ExtentPtr &getExtent(const crs::CRSNNPtr &crs) {
+    const auto &domains = crs->domains();
+    if (!domains.empty()) {
+        return domains[0]->domainOfValidity();
+    }
+    return nullExtent;
+}
+
+// ---------------------------------------------------------------------------
+
+static metadata::ExtentPtr
+getExtent(const std::vector<CoordinateOperationNNPtr> &ops,
+          bool conversionExtentIsWorld, bool &emptyIntersection) {
+    metadata::ExtentPtr res = nullptr;
+    for (const auto &subop : ops) {
+
+        const auto &subExtent =
+            getExtent(subop, conversionExtentIsWorld, emptyIntersection);
+        if (!subExtent) {
+            if (emptyIntersection) {
+                return nullptr;
+            }
+            continue;
+        }
+        if (res == nullptr) {
+            res = subExtent;
+        } else {
+            res = res->intersection(NN_NO_CHECK(subExtent));
+            if (!res) {
+                emptyIntersection = true;
+                return nullptr;
+            }
+        }
+    }
+    emptyIntersection = false;
+    return res;
+}
+
+// ---------------------------------------------------------------------------
+
+static double getPseudoArea(const metadata::ExtentPtr &extent) {
+    if (!extent)
+        return 0.0;
+    const auto &geographicElements = extent->geographicElements();
+    if (geographicElements.empty())
+        return 0.0;
+    auto bbox = dynamic_cast<const metadata::GeographicBoundingBox *>(
+        geographicElements[0].get());
+    if (!bbox)
+        return 0;
+    double w = bbox->westBoundLongitude();
+    double s = bbox->southBoundLatitude();
+    double e = bbox->eastBoundLongitude();
+    double n = bbox->northBoundLatitude();
+    if (w > e) {
+        e += 360.0;
+    }
+    // Integrate cos(lat) between south_lat and north_lat
+    return (e - w) * (std::sin(common::Angle(n).getSIValue()) -
+                      std::sin(common::Angle(s).getSIValue()));
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct CoordinateOperation::Private {
+    util::optional<std::string> operationVersion_{};
+    std::vector<metadata::PositionalAccuracyNNPtr>
+        coordinateOperationAccuracies_{};
+    std::weak_ptr<crs::CRS> sourceCRSWeak_{};
+    std::weak_ptr<crs::CRS> targetCRSWeak_{};
+    crs::CRSPtr interpolationCRS_{};
+    util::optional<common::DataEpoch> sourceCoordinateEpoch_{};
+    util::optional<common::DataEpoch> targetCoordinateEpoch_{};
+
+    // do not set this for a ProjectedCRS.definingConversion
+    struct CRSStrongRef {
+        crs::CRSNNPtr sourceCRS_;
+        crs::CRSNNPtr targetCRS_;
+        CRSStrongRef(const crs::CRSNNPtr &sourceCRSIn,
+                     const crs::CRSNNPtr &targetCRSIn)
+            : sourceCRS_(sourceCRSIn), targetCRS_(targetCRSIn) {}
+    };
+    std::unique_ptr<CRSStrongRef> strongRef_{};
+
+    Private() = default;
+    Private(const Private &other)
+        : operationVersion_(other.operationVersion_),
+          coordinateOperationAccuracies_(other.coordinateOperationAccuracies_),
+          sourceCRSWeak_(other.sourceCRSWeak_),
+          targetCRSWeak_(other.targetCRSWeak_),
+          interpolationCRS_(other.interpolationCRS_),
+          sourceCoordinateEpoch_(other.sourceCoordinateEpoch_),
+          targetCoordinateEpoch_(other.targetCoordinateEpoch_),
+          strongRef_(other.strongRef_ ? internal::make_unique<CRSStrongRef>(
+                                            *(other.strongRef_))
+                                      : nullptr) {}
+
+    Private &operator=(const Private &) = delete;
+};
+
+// ---------------------------------------------------------------------------
+
+GridDescription::GridDescription() = default;
+
+GridDescription::~GridDescription() = default;
+
+GridDescription::GridDescription(const GridDescription &) = default;
+
+GridDescription::GridDescription(GridDescription &&) noexcept = default;
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+CoordinateOperation::CoordinateOperation()
+    : d(internal::make_unique<Private>()) {}
+
+// ---------------------------------------------------------------------------
+
+CoordinateOperation::CoordinateOperation(const CoordinateOperation &other)
+    : ObjectUsage(other), d(internal::make_unique<Private>(*other.d)) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+CoordinateOperation::~CoordinateOperation() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the version of the coordinate transformation (i.e.
+ * instantiation
+ * due to the stochastic nature of the parameters).
+ *
+ * Mandatory when describing a coordinate transformation or point motion
+ * operation, and should not be supplied for a coordinate conversion.
+ *
+ * @return version or empty.
+ */
+const util::optional<std::string> &
+CoordinateOperation::operationVersion() const {
+    return d->operationVersion_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return estimate(s) of the impact of this coordinate operation on
+ * point accuracy.
+ *
+ * Gives position error estimates for target coordinates of this coordinate
+ * operation, assuming no errors in source coordinates.
+ *
+ * @return estimate(s) or empty vector.
+ */
+const std::vector<metadata::PositionalAccuracyNNPtr> &
+CoordinateOperation::coordinateOperationAccuracies() const {
+    return d->coordinateOperationAccuracies_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the source CRS of this coordinate operation.
+ *
+ * This should not be null, expect for of a derivingConversion of a DerivedCRS
+ * when the owning DerivedCRS has been destroyed.
+ *
+ * @return source CRS, or null.
+ */
+const crs::CRSPtr CoordinateOperation::sourceCRS() const {
+    return d->sourceCRSWeak_.lock();
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the target CRS of this coordinate operation.
+ *
+ * This should not be null, expect for of a derivingConversion of a DerivedCRS
+ * when the owning DerivedCRS has been destroyed.
+ *
+ * @return target CRS, or null.
+ */
+const crs::CRSPtr CoordinateOperation::targetCRS() const {
+    return d->targetCRSWeak_.lock();
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the interpolation CRS of this coordinate operation.
+ *
+ * @return interpolation CRS, or null.
+ */
+const crs::CRSPtr &CoordinateOperation::interpolationCRS() const {
+    return d->interpolationCRS_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the source epoch of coordinates.
+ *
+ * @return source epoch of coordinates, or empty.
+ */
+const util::optional<common::DataEpoch> &
+CoordinateOperation::sourceCoordinateEpoch() const {
+    return d->sourceCoordinateEpoch_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the target epoch of coordinates.
+ *
+ * @return target epoch of coordinates, or empty.
+ */
+const util::optional<common::DataEpoch> &
+CoordinateOperation::targetCoordinateEpoch() const {
+    return d->targetCoordinateEpoch_;
+}
+
+// ---------------------------------------------------------------------------
+
+void CoordinateOperation::setWeakSourceTargetCRS(
+    std::weak_ptr<crs::CRS> sourceCRSIn, std::weak_ptr<crs::CRS> targetCRSIn) {
+    d->sourceCRSWeak_ = sourceCRSIn;
+    d->targetCRSWeak_ = targetCRSIn;
+}
+
+// ---------------------------------------------------------------------------
+
+void CoordinateOperation::setCRSs(const crs::CRSNNPtr &sourceCRSIn,
+                                  const crs::CRSNNPtr &targetCRSIn,
+                                  const crs::CRSPtr &interpolationCRSIn) {
+    d->strongRef_ =
+        internal::make_unique<Private::CRSStrongRef>(sourceCRSIn, targetCRSIn);
+    d->sourceCRSWeak_ = sourceCRSIn.as_nullable();
+    d->targetCRSWeak_ = targetCRSIn.as_nullable();
+    d->interpolationCRS_ = interpolationCRSIn;
+}
+// ---------------------------------------------------------------------------
+
+void CoordinateOperation::setCRSs(const CoordinateOperation *in,
+                                  bool inverseSourceTarget) {
+    auto l_sourceCRS = in->sourceCRS();
+    auto l_targetCRS = in->targetCRS();
+    if (l_sourceCRS && l_targetCRS) {
+        auto nn_sourceCRS = NN_NO_CHECK(l_sourceCRS);
+        auto nn_targetCRS = NN_NO_CHECK(l_targetCRS);
+        if (inverseSourceTarget) {
+            setCRSs(nn_targetCRS, nn_sourceCRS, in->interpolationCRS());
+        } else {
+            setCRSs(nn_sourceCRS, nn_targetCRS, in->interpolationCRS());
+        }
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+void CoordinateOperation::setAccuracies(
+    const std::vector<metadata::PositionalAccuracyNNPtr> &accuracies) {
+    d->coordinateOperationAccuracies_ = accuracies;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return whether a coordinate operation can be instanciated as
+ * a PROJ pipeline, checking in particular that referenced grids are
+ * available.
+ */
+bool CoordinateOperation::isPROJInstanciable(
+    const io::DatabaseContextPtr &databaseContext) const {
+    try {
+        exportToPROJString(io::PROJStringFormatter::create().get());
+    } catch (const std::exception &) {
+        return false;
+    }
+    for (const auto &gridDesc : gridsNeeded(databaseContext)) {
+        if (!gridDesc.available) {
+            return false;
+        }
+    }
+    return true;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct OperationMethod::Private {
+    util::optional<std::string> formula_{};
+    util::optional<metadata::Citation> formulaCitation_{};
+    std::vector<GeneralOperationParameterNNPtr> parameters_{};
+    std::string projMethodOverride_{};
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+OperationMethod::OperationMethod() : d(internal::make_unique<Private>()) {}
+
+// ---------------------------------------------------------------------------
+
+OperationMethod::OperationMethod(const OperationMethod &other)
+    : IdentifiedObject(other), d(internal::make_unique<Private>(*other.d)) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+OperationMethod::~OperationMethod() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the formula(s) or procedure used by this coordinate operation
+ * method.
+ *
+ * This may be a reference to a publication (in which case use
+ * formulaCitation()).
+ *
+ * Note that the operation method may not be analytic, in which case this
+ * attribute references or contains the procedure, not an analytic formula.
+ *
+ * @return the formula, or empty.
+ */
+const util::optional<std::string> &OperationMethod::formula() PROJ_CONST_DEFN {
+    return d->formula_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return a reference to a publication giving the formula(s) or
+ * procedure
+ * used by the coordinate operation method.
+ *
+ * @return the formula citation, or empty.
+ */
+const util::optional<metadata::Citation> &
+OperationMethod::formulaCitation() PROJ_CONST_DEFN {
+    return d->formulaCitation_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the parameters of this operation method.
+ *
+ * @return the parameters.
+ */
+const std::vector<GeneralOperationParameterNNPtr> &
+OperationMethod::parameters() PROJ_CONST_DEFN {
+    return d->parameters_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instantiate a operation method from a vector of
+ * GeneralOperationParameter.
+ *
+ * @param properties See \ref general_properties. At minimum the name should be
+ * defined.
+ * @param parameters Vector of GeneralOperationParameterNNPtr.
+ * @return a new OperationMethod.
+ */
+OperationMethodNNPtr OperationMethod::create(
+    const util::PropertyMap &properties,
+    const std::vector<GeneralOperationParameterNNPtr> &parameters) {
+    OperationMethodNNPtr method(
+        OperationMethod::nn_make_shared<OperationMethod>());
+    method->assignSelf(method);
+    method->setProperties(properties);
+    method->d->parameters_ = parameters;
+    properties.getStringValue("proj_method", method->d->projMethodOverride_);
+    return method;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instantiate a operation method from a vector of OperationParameter.
+ *
+ * @param properties See \ref general_properties. At minimum the name should be
+ * defined.
+ * @param parameters Vector of OperationParameterNNPtr.
+ * @return a new OperationMethod.
+ */
+OperationMethodNNPtr OperationMethod::create(
+    const util::PropertyMap &properties,
+    const std::vector<OperationParameterNNPtr> &parameters) {
+    std::vector<GeneralOperationParameterNNPtr> parametersGeneral;
+    parametersGeneral.reserve(parameters.size());
+    for (const auto &p : parameters) {
+        parametersGeneral.push_back(p);
+    }
+    return create(properties, parametersGeneral);
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the EPSG code, either directly, or through the name
+ * @return code, or 0 if not found
+ */
+int OperationMethod::getEPSGCode() PROJ_CONST_DEFN {
+    int epsg_code = IdentifiedObject::getEPSGCode();
+    if (epsg_code == 0) {
+        auto l_name = nameStr();
+        if (ends_with(l_name, " (3D)")) {
+            l_name.resize(l_name.size() - strlen(" (3D)"));
+        }
+        for (const auto &tuple : methodNameCodes) {
+            if (metadata::Identifier::isEquivalentName(l_name.c_str(),
+                                                       tuple.name)) {
+                return tuple.epsg_code;
+            }
+        }
+    }
+    return epsg_code;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void OperationMethod::_exportToWKT(io::WKTFormatter *formatter) const {
+    const bool isWKT2 = formatter->version() == io::WKTFormatter::Version::WKT2;
+    formatter->startNode(isWKT2 ? io::WKTConstants::METHOD
+                                : io::WKTConstants::PROJECTION,
+                         !identifiers().empty());
+    std::string l_name(nameStr());
+    if (!isWKT2) {
+        const MethodMapping *mapping = getMapping(this);
+        if (mapping == nullptr) {
+            l_name = replaceAll(l_name, " ", "_");
+        } else {
+            if (l_name ==
+                PROJ_WKT2_NAME_METHOD_GEOSTATIONARY_SATELLITE_SWEEP_X) {
+                l_name = "Geostationary_Satellite";
+            } else {
+                if (mapping->wkt1_name == nullptr) {
+                    throw io::FormattingException(
+                        std::string("Unsupported conversion method: ") +
+                        mapping->wkt2_name);
+                }
+                l_name = mapping->wkt1_name;
+            }
+        }
+    }
+    formatter->addQuotedString(l_name);
+    if (formatter->outputId()) {
+        formatID(formatter);
+    }
+    formatter->endNode();
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+bool OperationMethod::_isEquivalentTo(
+    const util::IComparable *other,
+    util::IComparable::Criterion criterion) const {
+    auto otherOM = dynamic_cast<const OperationMethod *>(other);
+    if (otherOM == nullptr ||
+        !IdentifiedObject::_isEquivalentTo(other, criterion)) {
+        return false;
+    }
+    // TODO test formula and formulaCitation
+    const auto &params = parameters();
+    const auto &otherParams = otherOM->parameters();
+    const auto paramsSize = params.size();
+    if (paramsSize != otherParams.size()) {
+        return false;
+    }
+    if (criterion == util::IComparable::Criterion::STRICT) {
+        for (size_t i = 0; i < paramsSize; i++) {
+            if (!params[i]->_isEquivalentTo(otherParams[i].get(), criterion)) {
+                return false;
+            }
+        }
+    } else {
+        std::vector<bool> candidateIndices(paramsSize, true);
+        for (size_t i = 0; i < paramsSize; i++) {
+            bool found = false;
+            for (size_t j = 0; j < paramsSize; j++) {
+                if (candidateIndices[j] &&
+                    params[i]->_isEquivalentTo(otherParams[j].get(),
+                                               criterion)) {
+                    candidateIndices[j] = false;
+                    found = true;
+                    break;
+                }
+            }
+            if (!found) {
+                return false;
+            }
+        }
+    }
+    return true;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct GeneralParameterValue::Private {};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+GeneralParameterValue::GeneralParameterValue() : d(nullptr) {}
+
+// ---------------------------------------------------------------------------
+
+GeneralParameterValue::GeneralParameterValue(const GeneralParameterValue &)
+    : d(nullptr) {}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+GeneralParameterValue::~GeneralParameterValue() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct OperationParameterValue::Private {
+    OperationParameterNNPtr parameter;
+    ParameterValueNNPtr parameterValue;
+
+    Private(const OperationParameterNNPtr &parameterIn,
+            const ParameterValueNNPtr &valueIn)
+        : parameter(parameterIn), parameterValue(valueIn) {}
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+OperationParameterValue::OperationParameterValue(
+    const OperationParameterValue &other)
+    : GeneralParameterValue(other),
+      d(internal::make_unique<Private>(*other.d)) {}
+
+// ---------------------------------------------------------------------------
+
+OperationParameterValue::OperationParameterValue(
+    const OperationParameterNNPtr &parameterIn,
+    const ParameterValueNNPtr &valueIn)
+    : GeneralParameterValue(),
+      d(internal::make_unique<Private>(parameterIn, valueIn)) {}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instantiate a OperationParameterValue.
+ *
+ * @param parameterIn Parameter (definition).
+ * @param valueIn Parameter value.
+ * @return a new OperationParameterValue.
+ */
+OperationParameterValueNNPtr
+OperationParameterValue::create(const OperationParameterNNPtr &parameterIn,
+                                const ParameterValueNNPtr &valueIn) {
+    return OperationParameterValue::nn_make_shared<OperationParameterValue>(
+        parameterIn, valueIn);
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+OperationParameterValue::~OperationParameterValue() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the parameter (definition)
+ *
+ * @return the parameter (definition).
+ */
+const OperationParameterNNPtr &
+OperationParameterValue::parameter() PROJ_CONST_DEFN {
+    return d->parameter;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the parameter value.
+ *
+ * @return the parameter value.
+ */
+const ParameterValueNNPtr &
+OperationParameterValue::parameterValue() PROJ_CONST_DEFN {
+    return d->parameterValue;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void OperationParameterValue::_exportToWKT(
+    // cppcheck-suppress passedByValue
+    io::WKTFormatter *formatter) const {
+    _exportToWKT(formatter, nullptr);
+}
+
+void OperationParameterValue::_exportToWKT(io::WKTFormatter *formatter,
+                                           const MethodMapping *mapping) const {
+    const ParamMapping *paramMapping =
+        mapping ? getMapping(mapping, d->parameter) : nullptr;
+    if (paramMapping && paramMapping->wkt1_name == nullptr) {
+        return;
+    }
+    const bool isWKT2 = formatter->version() == io::WKTFormatter::Version::WKT2;
+    if (isWKT2 && parameterValue()->type() == ParameterValue::Type::FILENAME) {
+        formatter->startNode(io::WKTConstants::PARAMETERFILE,
+                             !parameter()->identifiers().empty());
+    } else {
+        formatter->startNode(io::WKTConstants::PARAMETER,
+                             !parameter()->identifiers().empty());
+    }
+    if (paramMapping) {
+        formatter->addQuotedString(paramMapping->wkt1_name);
+    } else {
+        formatter->addQuotedString(parameter()->nameStr());
+    }
+    parameterValue()->_exportToWKT(formatter);
+    if (formatter->outputId()) {
+        parameter()->formatID(formatter);
+    }
+    formatter->endNode();
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+/** Utility method used on WKT2 import to convert from abridged transformation
+ * to "normal" transformation parameters.
+ */
+bool OperationParameterValue::convertFromAbridged(
+    const std::string &paramName, double &val,
+    const common::UnitOfMeasure *&unit, int &paramEPSGCode) {
+    if (metadata::Identifier::isEquivalentName(
+            paramName.c_str(), EPSG_NAME_PARAMETER_X_AXIS_TRANSLATION) ||
+        paramEPSGCode == EPSG_CODE_PARAMETER_X_AXIS_TRANSLATION) {
+        unit = &common::UnitOfMeasure::METRE;
+        paramEPSGCode = EPSG_CODE_PARAMETER_X_AXIS_TRANSLATION;
+        return true;
+    } else if (metadata::Identifier::isEquivalentName(
+                   paramName.c_str(), EPSG_NAME_PARAMETER_Y_AXIS_TRANSLATION) ||
+               paramEPSGCode == EPSG_CODE_PARAMETER_Y_AXIS_TRANSLATION) {
+        unit = &common::UnitOfMeasure::METRE;
+        paramEPSGCode = EPSG_CODE_PARAMETER_Y_AXIS_TRANSLATION;
+        return true;
+    } else if (metadata::Identifier::isEquivalentName(
+                   paramName.c_str(), EPSG_NAME_PARAMETER_Z_AXIS_TRANSLATION) ||
+               paramEPSGCode == EPSG_CODE_PARAMETER_Z_AXIS_TRANSLATION) {
+        unit = &common::UnitOfMeasure::METRE;
+        paramEPSGCode = EPSG_CODE_PARAMETER_Z_AXIS_TRANSLATION;
+        return true;
+    } else if (metadata::Identifier::isEquivalentName(
+                   paramName.c_str(), EPSG_NAME_PARAMETER_X_AXIS_ROTATION) ||
+               paramEPSGCode == EPSG_CODE_PARAMETER_X_AXIS_ROTATION) {
+        unit = &common::UnitOfMeasure::ARC_SECOND;
+        paramEPSGCode = EPSG_CODE_PARAMETER_X_AXIS_ROTATION;
+        return true;
+    } else if (metadata::Identifier::isEquivalentName(
+                   paramName.c_str(), EPSG_NAME_PARAMETER_Y_AXIS_ROTATION) ||
+               paramEPSGCode == EPSG_CODE_PARAMETER_Y_AXIS_ROTATION) {
+        unit = &common::UnitOfMeasure::ARC_SECOND;
+        paramEPSGCode = EPSG_CODE_PARAMETER_Y_AXIS_ROTATION;
+        return true;
+
+    } else if (metadata::Identifier::isEquivalentName(
+                   paramName.c_str(), EPSG_NAME_PARAMETER_Z_AXIS_ROTATION) ||
+               paramEPSGCode == EPSG_CODE_PARAMETER_Z_AXIS_ROTATION) {
+        unit = &common::UnitOfMeasure::ARC_SECOND;
+        paramEPSGCode = EPSG_CODE_PARAMETER_Z_AXIS_ROTATION;
+        return true;
+
+    } else if (metadata::Identifier::isEquivalentName(
+                   paramName.c_str(), EPSG_NAME_PARAMETER_SCALE_DIFFERENCE) ||
+               paramEPSGCode == EPSG_CODE_PARAMETER_SCALE_DIFFERENCE) {
+        val = (val - 1.0) * 1e6;
+        unit = &common::UnitOfMeasure::PARTS_PER_MILLION;
+        paramEPSGCode = EPSG_CODE_PARAMETER_SCALE_DIFFERENCE;
+        return true;
+    }
+    return false;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+bool OperationParameterValue::_isEquivalentTo(
+    const util::IComparable *other,
+    util::IComparable::Criterion criterion) const {
+    auto otherOPV = dynamic_cast<const OperationParameterValue *>(other);
+    if (otherOPV == nullptr) {
+        return false;
+    }
+    if (!d->parameter->_isEquivalentTo(otherOPV->d->parameter.get(),
+                                       criterion)) {
+        return false;
+    }
+    if (criterion == util::IComparable::Criterion::STRICT) {
+        return d->parameterValue->_isEquivalentTo(
+            otherOPV->d->parameterValue.get(), criterion);
+    }
+    if (d->parameterValue->_isEquivalentTo(otherOPV->d->parameterValue.get(),
+                                           criterion)) {
+        return true;
+    }
+    if (d->parameter->getEPSGCode() ==
+            EPSG_CODE_PARAMETER_AZIMUTH_INITIAL_LINE ||
+        d->parameter->getEPSGCode() ==
+            EPSG_CODE_PARAMETER_ANGLE_RECTIFIED_TO_SKEW_GRID) {
+        if (parameterValue()->type() == ParameterValue::Type::MEASURE &&
+            otherOPV->parameterValue()->type() ==
+                ParameterValue::Type::MEASURE) {
+            const double a = std::fmod(parameterValue()->value().convertToUnit(
+                                           common::UnitOfMeasure::DEGREE) +
+                                           360.0,
+                                       360.0);
+            const double b =
+                std::fmod(otherOPV->parameterValue()->value().convertToUnit(
+                              common::UnitOfMeasure::DEGREE) +
+                              360.0,
+                          360.0);
+            return std::fabs(a - b) <= 1e-10 * std::fabs(a);
+        }
+    }
+    return false;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct GeneralOperationParameter::Private {};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+GeneralOperationParameter::GeneralOperationParameter() : d(nullptr) {}
+
+// ---------------------------------------------------------------------------
+
+GeneralOperationParameter::GeneralOperationParameter(
+    const GeneralOperationParameter &other)
+    : IdentifiedObject(other), d(nullptr) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+GeneralOperationParameter::~GeneralOperationParameter() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct OperationParameter::Private {};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+OperationParameter::OperationParameter() : d(nullptr) {}
+
+// ---------------------------------------------------------------------------
+
+OperationParameter::OperationParameter(const OperationParameter &other)
+    : GeneralOperationParameter(other), d(nullptr) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+OperationParameter::~OperationParameter() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instantiate a OperationParameter.
+ *
+ * @param properties See \ref general_properties. At minimum the name should be
+ * defined.
+ * @return a new OperationParameter.
+ */
+OperationParameterNNPtr
+OperationParameter::create(const util::PropertyMap &properties) {
+    OperationParameterNNPtr op(
+        OperationParameter::nn_make_shared<OperationParameter>());
+    op->assignSelf(op);
+    op->setProperties(properties);
+    return op;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+bool OperationParameter::_isEquivalentTo(
+    const util::IComparable *other,
+    util::IComparable::Criterion criterion) const {
+    auto otherOP = dynamic_cast<const OperationParameter *>(other);
+    if (otherOP == nullptr) {
+        return false;
+    }
+    if (criterion == util::IComparable::Criterion::STRICT) {
+        return IdentifiedObject::_isEquivalentTo(other, criterion);
+    }
+    if (IdentifiedObject::_isEquivalentTo(other, criterion)) {
+        return true;
+    }
+    auto l_epsgCode = getEPSGCode();
+    return l_epsgCode != 0 && l_epsgCode == otherOP->getEPSGCode();
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+void OperationParameter::_exportToWKT(io::WKTFormatter *) const {}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the name of a parameter designed by its EPSG code
+ * @return name, or nullptr if not found
+ */
+const char *OperationParameter::getNameForEPSGCode(int epsg_code) noexcept {
+    for (const auto &tuple : paramNameCodes) {
+        if (tuple.epsg_code == epsg_code) {
+            return tuple.name;
+        }
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the EPSG code, either directly, or through the name
+ * @return code, or 0 if not found
+ */
+int OperationParameter::getEPSGCode() PROJ_CONST_DEFN {
+    int epsg_code = IdentifiedObject::getEPSGCode();
+    if (epsg_code == 0) {
+        const auto &l_name = nameStr();
+        for (const auto &tuple : paramNameCodes) {
+            if (metadata::Identifier::isEquivalentName(l_name.c_str(),
+                                                       tuple.name)) {
+                return tuple.epsg_code;
+            }
+        }
+        if (metadata::Identifier::isEquivalentName(l_name.c_str(),
+                                                   "Latitude of origin")) {
+            return EPSG_CODE_PARAMETER_LATITUDE_OF_NATURAL_ORIGIN;
+        }
+        if (metadata::Identifier::isEquivalentName(l_name.c_str(),
+                                                   "Scale factor")) {
+            return EPSG_CODE_PARAMETER_SCALE_FACTOR_AT_NATURAL_ORIGIN;
+        }
+    }
+    return epsg_code;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct SingleOperation::Private {
+    std::vector<GeneralParameterValueNNPtr> parameterValues_{};
+    OperationMethodNNPtr method_;
+
+    explicit Private(const OperationMethodNNPtr &methodIn)
+        : method_(methodIn) {}
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+SingleOperation::SingleOperation(const OperationMethodNNPtr &methodIn)
+    : d(internal::make_unique<Private>(methodIn)) {}
+
+// ---------------------------------------------------------------------------
+
+SingleOperation::SingleOperation(const SingleOperation &other)
+    :
+#if !defined(COMPILER_WARNS_ABOUT_ABSTRACT_VBASE_INIT)
+      CoordinateOperation(other),
+#endif
+      d(internal::make_unique<Private>(*other.d)) {
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+SingleOperation::~SingleOperation() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the parameter values.
+ *
+ * @return the parameter values.
+ */
+const std::vector<GeneralParameterValueNNPtr> &
+SingleOperation::parameterValues() PROJ_CONST_DEFN {
+    return d->parameterValues_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the operation method associated to the operation.
+ *
+ * @return the operation method.
+ */
+const OperationMethodNNPtr &SingleOperation::method() PROJ_CONST_DEFN {
+    return d->method_;
+}
+
+// ---------------------------------------------------------------------------
+
+void SingleOperation::setParameterValues(
+    const std::vector<GeneralParameterValueNNPtr> &values) {
+    d->parameterValues_ = values;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static const ParameterValuePtr nullParameterValue;
+//! @endcond
+
+/** \brief Return the parameter value corresponding to a parameter name or
+ * EPSG code
+ *
+ * @param paramName the parameter name (or empty, in which case epsg_code
+ *                  should be non zero)
+ * @param epsg_code the parameter EPSG code (possibly zero)
+ * @return the value, or nullptr if not found.
+ */
+const ParameterValuePtr &
+SingleOperation::parameterValue(const std::string &paramName,
+                                int epsg_code) const noexcept {
+    if (epsg_code) {
+        for (const auto &genOpParamvalue : parameterValues()) {
+            auto opParamvalue = dynamic_cast<const OperationParameterValue *>(
+                genOpParamvalue.get());
+            if (opParamvalue) {
+                const auto &parameter = opParamvalue->parameter();
+                if (parameter->getEPSGCode() == epsg_code) {
+                    return opParamvalue->parameterValue();
+                }
+            }
+        }
+    }
+    for (const auto &genOpParamvalue : parameterValues()) {
+        auto opParamvalue = dynamic_cast<const OperationParameterValue *>(
+            genOpParamvalue.get());
+        if (opParamvalue) {
+            const auto &parameter = opParamvalue->parameter();
+            if (metadata::Identifier::isEquivalentName(
+                    paramName.c_str(), parameter->nameStr().c_str())) {
+                return opParamvalue->parameterValue();
+            }
+        }
+    }
+    for (const auto &genOpParamvalue : parameterValues()) {
+        auto opParamvalue = dynamic_cast<const OperationParameterValue *>(
+            genOpParamvalue.get());
+        if (opParamvalue) {
+            const auto &parameter = opParamvalue->parameter();
+            if (areEquivalentParameters(paramName, parameter->nameStr())) {
+                return opParamvalue->parameterValue();
+            }
+        }
+    }
+    return nullParameterValue;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the parameter value corresponding to a EPSG code
+ *
+ * @param epsg_code the parameter EPSG code
+ * @return the value, or nullptr if not found.
+ */
+const ParameterValuePtr &SingleOperation::parameterValue(int epsg_code) const
+    noexcept {
+    for (const auto &genOpParamvalue : parameterValues()) {
+        auto opParamvalue = dynamic_cast<const OperationParameterValue *>(
+            genOpParamvalue.get());
+        if (opParamvalue) {
+            const auto &parameter = opParamvalue->parameter();
+            if (parameter->getEPSGCode() == epsg_code) {
+                return opParamvalue->parameterValue();
+            }
+        }
+    }
+    return nullParameterValue;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static const common::Measure nullMeasure;
+//! @endcond
+
+/** \brief Return the parameter value, as a measure, corresponding to a
+ * parameter name or EPSG code
+ *
+ * @param paramName the parameter name (or empty, in which case epsg_code
+ *                  should be non zero)
+ * @param epsg_code the parameter EPSG code (possibly zero)
+ * @return the measure, or the empty Measure() object if not found.
+ */
+const common::Measure &
+SingleOperation::parameterValueMeasure(const std::string &paramName,
+                                       int epsg_code) const noexcept {
+    const auto &val = parameterValue(paramName, epsg_code);
+    if (val && val->type() == ParameterValue::Type::MEASURE) {
+        return val->value();
+    }
+    return nullMeasure;
+}
+
+/** \brief Return the parameter value, as a measure, corresponding to a
+ * EPSG code
+ *
+ * @param epsg_code the parameter EPSG code
+ * @return the measure, or the empty Measure() object if not found.
+ */
+const common::Measure &
+SingleOperation::parameterValueMeasure(int epsg_code) const noexcept {
+    const auto &val = parameterValue(epsg_code);
+    if (val && val->type() == ParameterValue::Type::MEASURE) {
+        return val->value();
+    }
+    return nullMeasure;
+}
+
+//! @cond Doxygen_Suppress
+
+double SingleOperation::parameterValueNumericAsSI(int epsg_code) const
+    noexcept {
+    const auto &val = parameterValue(epsg_code);
+    if (val && val->type() == ParameterValue::Type::MEASURE) {
+        return val->value().getSIValue();
+    }
+    return 0.0;
+}
+
+double SingleOperation::parameterValueNumeric(
+    int epsg_code, const common::UnitOfMeasure &targetUnit) const noexcept {
+    const auto &val = parameterValue(epsg_code);
+    if (val && val->type() == ParameterValue::Type::MEASURE) {
+        return val->value().convertToUnit(targetUnit);
+    }
+    return 0.0;
+}
+
+//! @endcond
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a PROJ-based single operation.
+ *
+ * \note The operation might internally be a pipeline chaining several
+ * operations.
+ * The use of the SingleOperation modeling here is mostly to be able to get
+ * the PROJ string as a parameter.
+ *
+ * @param properties Properties
+ * @param PROJString the PROJ string.
+ * @param sourceCRS source CRS (might be null).
+ * @param targetCRS target CRS (might be null).
+ * @param accuracies Vector of positional accuracy (might be empty).
+ * @return the new instance
+ */
+SingleOperationNNPtr SingleOperation::createPROJBased(
+    const util::PropertyMap &properties, const std::string &PROJString,
+    const crs::CRSPtr &sourceCRS, const crs::CRSPtr &targetCRS,
+    const std::vector<metadata::PositionalAccuracyNNPtr> &accuracies) {
+    return util::nn_static_pointer_cast<SingleOperation>(
+        PROJBasedOperation::create(properties, PROJString, sourceCRS, targetCRS,
+                                   accuracies));
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static SingleOperationNNPtr createPROJBased(
+    const util::PropertyMap &properties,
+    const io::IPROJStringExportableNNPtr &projExportable,
+    const crs::CRSNNPtr &sourceCRS, const crs::CRSNNPtr &targetCRS,
+    const std::vector<metadata::PositionalAccuracyNNPtr> &accuracies =
+        std::vector<metadata::PositionalAccuracyNNPtr>()) {
+    return util::nn_static_pointer_cast<SingleOperation>(
+        PROJBasedOperation::create(properties, projExportable, false, sourceCRS,
+                                   targetCRS, accuracies));
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+bool SingleOperation::_isEquivalentTo(
+    const util::IComparable *other,
+    util::IComparable::Criterion criterion) const {
+    return _isEquivalentTo(other, criterion, false);
+}
+
+bool SingleOperation::_isEquivalentTo(const util::IComparable *other,
+                                      util::IComparable::Criterion criterion,
+                                      bool inOtherDirection) const {
+
+    auto otherSO = dynamic_cast<const SingleOperation *>(other);
+    if (otherSO == nullptr ||
+        (criterion == util::IComparable::Criterion::STRICT &&
+         !ObjectUsage::_isEquivalentTo(other, criterion))) {
+        return false;
+    }
+
+    const int methodEPSGCode = d->method_->getEPSGCode();
+    const int otherMethodEPSGCode = otherSO->d->method_->getEPSGCode();
+
+    bool equivalentMethods =
+        (criterion == util::IComparable::Criterion::EQUIVALENT &&
+         methodEPSGCode != 0 && methodEPSGCode == otherMethodEPSGCode) ||
+        d->method_->_isEquivalentTo(otherSO->d->method_.get(), criterion);
+    if (!equivalentMethods &&
+        criterion == util::IComparable::Criterion::EQUIVALENT) {
+        if ((methodEPSGCode == EPSG_CODE_METHOD_LAMBERT_AZIMUTHAL_EQUAL_AREA &&
+             otherMethodEPSGCode ==
+                 EPSG_CODE_METHOD_LAMBERT_AZIMUTHAL_EQUAL_AREA_SPHERICAL) ||
+            (otherMethodEPSGCode ==
+                 EPSG_CODE_METHOD_LAMBERT_AZIMUTHAL_EQUAL_AREA &&
+             methodEPSGCode ==
+                 EPSG_CODE_METHOD_LAMBERT_AZIMUTHAL_EQUAL_AREA_SPHERICAL) ||
+            (methodEPSGCode == EPSG_CODE_METHOD_EQUIDISTANT_CYLINDRICAL &&
+             otherMethodEPSGCode ==
+                 EPSG_CODE_METHOD_EQUIDISTANT_CYLINDRICAL_SPHERICAL) ||
+            (otherMethodEPSGCode == EPSG_CODE_METHOD_EQUIDISTANT_CYLINDRICAL &&
+             methodEPSGCode ==
+                 EPSG_CODE_METHOD_EQUIDISTANT_CYLINDRICAL_SPHERICAL)) {
+            auto geodCRS =
+                dynamic_cast<const crs::GeodeticCRS *>(sourceCRS().get());
+            auto otherGeodCRS = dynamic_cast<const crs::GeodeticCRS *>(
+                otherSO->sourceCRS().get());
+            if (geodCRS && otherGeodCRS && geodCRS->ellipsoid()->isSphere() &&
+                otherGeodCRS->ellipsoid()->isSphere()) {
+                equivalentMethods = true;
+            }
+        }
+    }
+
+    if (!equivalentMethods) {
+        if (criterion == util::IComparable::Criterion::EQUIVALENT) {
+
+            const auto isTOWGS84Transf = [](int code) {
+                return code ==
+                           EPSG_CODE_METHOD_GEOCENTRIC_TRANSLATION_GEOCENTRIC ||
+                       code == EPSG_CODE_METHOD_POSITION_VECTOR_GEOCENTRIC ||
+                       code == EPSG_CODE_METHOD_COORDINATE_FRAME_GEOCENTRIC ||
+                       code ==
+                           EPSG_CODE_METHOD_GEOCENTRIC_TRANSLATION_GEOGRAPHIC_2D ||
+                       code == EPSG_CODE_METHOD_POSITION_VECTOR_GEOGRAPHIC_2D ||
+                       code ==
+                           EPSG_CODE_METHOD_COORDINATE_FRAME_GEOGRAPHIC_2D ||
+                       code ==
+                           EPSG_CODE_METHOD_GEOCENTRIC_TRANSLATION_GEOGRAPHIC_3D ||
+                       code == EPSG_CODE_METHOD_POSITION_VECTOR_GEOGRAPHIC_3D ||
+                       code == EPSG_CODE_METHOD_COORDINATE_FRAME_GEOGRAPHIC_3D;
+            };
+
+            // Translation vs (PV or CF)
+            // or different PV vs CF convention
+            if (isTOWGS84Transf(methodEPSGCode) &&
+                isTOWGS84Transf(otherMethodEPSGCode)) {
+                auto transf = static_cast<const Transformation *>(this);
+                auto otherTransf = static_cast<const Transformation *>(otherSO);
+                auto params = transf->getTOWGS84Parameters();
+                auto otherParams = otherTransf->getTOWGS84Parameters();
+                assert(params.size() == 7);
+                assert(otherParams.size() == 7);
+                for (size_t i = 0; i < 7; i++) {
+                    if (std::fabs(params[i] - otherParams[i]) >
+                        1e-10 * std::fabs(params[i])) {
+                        return false;
+                    }
+                }
+                return true;
+            }
+
+            // _1SP methods can sometimes be equivalent to _2SP ones
+            // Check it by using convertToOtherMethod()
+            if (methodEPSGCode ==
+                    EPSG_CODE_METHOD_LAMBERT_CONIC_CONFORMAL_1SP &&
+                otherMethodEPSGCode ==
+                    EPSG_CODE_METHOD_LAMBERT_CONIC_CONFORMAL_2SP) {
+                // Convert from 2SP to 1SP as the other direction has more
+                // degree of liberties.
+                return otherSO->_isEquivalentTo(this, criterion);
+            } else if ((methodEPSGCode == EPSG_CODE_METHOD_MERCATOR_VARIANT_A &&
+                        otherMethodEPSGCode ==
+                            EPSG_CODE_METHOD_MERCATOR_VARIANT_B) ||
+                       (methodEPSGCode == EPSG_CODE_METHOD_MERCATOR_VARIANT_B &&
+                        otherMethodEPSGCode ==
+                            EPSG_CODE_METHOD_MERCATOR_VARIANT_A) ||
+                       (methodEPSGCode ==
+                            EPSG_CODE_METHOD_LAMBERT_CONIC_CONFORMAL_2SP &&
+                        otherMethodEPSGCode ==
+                            EPSG_CODE_METHOD_LAMBERT_CONIC_CONFORMAL_1SP)) {
+                auto conv = dynamic_cast<const Conversion *>(this);
+                if (conv) {
+                    auto eqConv =
+                        conv->convertToOtherMethod(otherMethodEPSGCode);
+                    if (eqConv) {
+                        return eqConv->_isEquivalentTo(other, criterion);
+                    }
+                }
+            }
+        }
+
+        return false;
+    }
+
+    const auto &values = d->parameterValues_;
+    const auto &otherValues = otherSO->d->parameterValues_;
+    const auto valuesSize = values.size();
+    const auto otherValuesSize = otherValues.size();
+    if (criterion == util::IComparable::Criterion::STRICT) {
+        if (valuesSize != otherValuesSize) {
+            return false;
+        }
+        for (size_t i = 0; i < valuesSize; i++) {
+            if (!values[i]->_isEquivalentTo(otherValues[i].get(), criterion)) {
+                return false;
+            }
+        }
+        return true;
+    }
+
+    std::vector<bool> candidateIndices(otherValuesSize, true);
+    bool equivalent = true;
+    bool foundMissingArgs = valuesSize != otherValuesSize;
+
+    for (size_t i = 0; equivalent && i < valuesSize; i++) {
+        auto opParamvalue =
+            dynamic_cast<const OperationParameterValue *>(values[i].get());
+        if (!opParamvalue)
+            return false;
+
+        equivalent = false;
+        bool sameNameDifferentValue = false;
+        for (size_t j = 0; j < otherValuesSize; j++) {
+            if (candidateIndices[j] &&
+                values[i]->_isEquivalentTo(otherValues[j].get(), criterion)) {
+                candidateIndices[j] = false;
+                equivalent = true;
+                break;
+            } else if (candidateIndices[j]) {
+                auto otherOpParamvalue =
+                    dynamic_cast<const OperationParameterValue *>(
+                        otherValues[j].get());
+                if (!otherOpParamvalue)
+                    return false;
+                sameNameDifferentValue =
+                    opParamvalue->parameter()->_isEquivalentTo(
+                        otherOpParamvalue->parameter().get(), criterion);
+                if (sameNameDifferentValue) {
+                    candidateIndices[j] = false;
+                    break;
+                }
+            }
+        }
+
+        if (!equivalent &&
+            methodEPSGCode == EPSG_CODE_METHOD_LAMBERT_CONIC_CONFORMAL_2SP) {
+            // For LCC_2SP, the standard parallels can be switched and
+            // this will result in the same result.
+            const int paramEPSGCode = opParamvalue->parameter()->getEPSGCode();
+            if (paramEPSGCode ==
+                    EPSG_CODE_PARAMETER_LATITUDE_1ST_STD_PARALLEL ||
+                paramEPSGCode ==
+                    EPSG_CODE_PARAMETER_LATITUDE_2ND_STD_PARALLEL) {
+                auto value_1st = parameterValue(
+                    EPSG_CODE_PARAMETER_LATITUDE_1ST_STD_PARALLEL);
+                auto value_2nd = parameterValue(
+                    EPSG_CODE_PARAMETER_LATITUDE_2ND_STD_PARALLEL);
+                if (value_1st && value_2nd) {
+                    equivalent =
+                        value_1st->_isEquivalentTo(
+                            otherSO
+                                ->parameterValue(
+                                    EPSG_CODE_PARAMETER_LATITUDE_2ND_STD_PARALLEL)
+                                .get(),
+                            criterion) &&
+                        value_2nd->_isEquivalentTo(
+                            otherSO
+                                ->parameterValue(
+                                    EPSG_CODE_PARAMETER_LATITUDE_1ST_STD_PARALLEL)
+                                .get(),
+                            criterion);
+                }
+            }
+        }
+
+        if (equivalent) {
+            continue;
+        }
+
+        if (sameNameDifferentValue) {
+            break;
+        }
+
+        // If there are parameters in this method not found in the other one,
+        // check that they are set to a default neutral value, that is 1
+        // for scale, and 0 otherwise.
+        foundMissingArgs = true;
+        const auto &value = opParamvalue->parameterValue();
+        if (value->type() != ParameterValue::Type::MEASURE) {
+            break;
+        }
+        if (value->value().unit().type() ==
+            common::UnitOfMeasure::Type::SCALE) {
+            equivalent = value->value().getSIValue() == 1.0;
+        } else {
+            equivalent = value->value().getSIValue() == 0.0;
+        }
+    }
+
+    // In the case the arguments don't perfectly match, try the reverse
+    // check.
+    if (equivalent && foundMissingArgs && !inOtherDirection) {
+        return otherSO->_isEquivalentTo(this, criterion, true);
+    }
+
+    // Equivalent formulations of 2SP can have different parameters
+    // Then convert to 1SP and compare.
+    if (!equivalent &&
+        methodEPSGCode == EPSG_CODE_METHOD_LAMBERT_CONIC_CONFORMAL_2SP) {
+        auto conv = dynamic_cast<const Conversion *>(this);
+        auto otherConv = dynamic_cast<const Conversion *>(other);
+        if (conv && otherConv) {
+            auto thisAs1SP = conv->convertToOtherMethod(
+                EPSG_CODE_METHOD_LAMBERT_CONIC_CONFORMAL_1SP);
+            auto otherAs1SP = otherConv->convertToOtherMethod(
+                EPSG_CODE_METHOD_LAMBERT_CONIC_CONFORMAL_1SP);
+            if (thisAs1SP && otherAs1SP) {
+                equivalent =
+                    thisAs1SP->_isEquivalentTo(otherAs1SP.get(), criterion);
+            }
+        }
+    }
+    return equivalent;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+std::set<GridDescription> SingleOperation::gridsNeeded(
+    const io::DatabaseContextPtr &databaseContext) const {
+    std::set<GridDescription> res;
+    for (const auto &genOpParamvalue : parameterValues()) {
+        auto opParamvalue = dynamic_cast<const OperationParameterValue *>(
+            genOpParamvalue.get());
+        if (opParamvalue) {
+            const auto &value = opParamvalue->parameterValue();
+            if (value->type() == ParameterValue::Type::FILENAME) {
+                GridDescription desc;
+                desc.shortName = value->valueFile();
+                if (databaseContext) {
+                    databaseContext->lookForGridInfo(
+                        desc.shortName, desc.fullName, desc.packageName,
+                        desc.url, desc.directDownload, desc.openLicense,
+                        desc.available);
+                }
+                res.insert(desc);
+            }
+        }
+    }
+    return res;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Validate the parameters used by a coodinate operation.
+ *
+ * Return whether the method is known or not, or a list of missing or extra
+ * parameters for the operations recognized by this implementation.
+ */
+std::list<std::string> SingleOperation::validateParameters() const {
+    std::list<std::string> res;
+
+    const auto &l_method = method();
+    const auto &methodName = l_method->nameStr();
+    const MethodMapping *methodMapping = nullptr;
+    const auto methodEPSGCode = l_method->getEPSGCode();
+    for (const auto &mapping : projectionMethodMappings) {
+        if (metadata::Identifier::isEquivalentName(mapping.wkt2_name,
+                                                   methodName.c_str()) ||
+            (methodEPSGCode != 0 && methodEPSGCode == mapping.epsg_code)) {
+            methodMapping = &mapping;
+        }
+    }
+    if (methodMapping == nullptr) {
+        for (const auto &mapping : otherMethodMappings) {
+            if (metadata::Identifier::isEquivalentName(mapping.wkt2_name,
+                                                       methodName.c_str()) ||
+                (methodEPSGCode != 0 && methodEPSGCode == mapping.epsg_code)) {
+                methodMapping = &mapping;
+            }
+        }
+    }
+    if (!methodMapping) {
+        res.emplace_back("Unknown method " + methodName);
+        return res;
+    }
+    if (methodMapping->wkt2_name != methodName) {
+        if (metadata::Identifier::isEquivalentName(methodMapping->wkt2_name,
+                                                   methodName.c_str())) {
+            std::string msg("Method name ");
+            msg += methodName;
+            msg += " is equivalent to official ";
+            msg += methodMapping->wkt2_name;
+            msg += " but not strictly equal";
+            res.emplace_back(msg);
+        } else {
+            std::string msg("Method name ");
+            msg += methodName;
+            msg += ", matched to ";
+            msg += methodMapping->wkt2_name;
+            msg += ", through its EPSG code has not an equivalent name";
+            res.emplace_back(msg);
+        }
+    }
+    if (methodEPSGCode != 0 && methodEPSGCode != methodMapping->epsg_code) {
+        std::string msg("Method of EPSG code ");
+        msg += toString(methodEPSGCode);
+        msg += " does not match official code (";
+        msg += toString(methodMapping->epsg_code);
+        msg += ')';
+        res.emplace_back(msg);
+    }
+
+    // Check if expected parameters are found
+    for (int i = 0;
+         methodMapping->params && methodMapping->params[i] != nullptr; ++i) {
+        const auto *paramMapping = methodMapping->params[i];
+
+        const OperationParameterValue *opv = nullptr;
+        for (const auto &genOpParamvalue : parameterValues()) {
+            auto opParamvalue = dynamic_cast<const OperationParameterValue *>(
+                genOpParamvalue.get());
+            if (opParamvalue) {
+                const auto &parameter = opParamvalue->parameter();
+                if ((paramMapping->epsg_code != 0 &&
+                     parameter->getEPSGCode() == paramMapping->epsg_code) ||
+                    ci_equal(parameter->nameStr(), paramMapping->wkt2_name)) {
+                    opv = opParamvalue;
+                    break;
+                }
+            }
+        }
+
+        if (!opv) {
+            std::string msg("Cannot find expected parameter ");
+            msg += paramMapping->wkt2_name;
+            res.emplace_back(msg);
+            continue;
+        }
+        const auto &parameter = opv->parameter();
+        if (paramMapping->wkt2_name != parameter->nameStr()) {
+            if (ci_equal(parameter->nameStr(), paramMapping->wkt2_name)) {
+                std::string msg("Parameter name ");
+                msg += parameter->nameStr();
+                msg += " is equivalent to official ";
+                msg += paramMapping->wkt2_name;
+                msg += " but not strictly equal";
+                res.emplace_back(msg);
+            } else {
+                std::string msg("Parameter name ");
+                msg += parameter->nameStr();
+                msg += ", matched to ";
+                msg += paramMapping->wkt2_name;
+                msg += ", through its EPSG code has not an equivalent name";
+                res.emplace_back(msg);
+            }
+        }
+        const auto paramEPSGCode = parameter->getEPSGCode();
+        if (paramEPSGCode != 0 && paramEPSGCode != paramMapping->epsg_code) {
+            std::string msg("Paramater of EPSG code ");
+            msg += toString(paramEPSGCode);
+            msg += " does not match official code (";
+            msg += toString(paramMapping->epsg_code);
+            msg += ')';
+            res.emplace_back(msg);
+        }
+    }
+
+    // Check if there are extra parameters
+    for (const auto &genOpParamvalue : parameterValues()) {
+        auto opParamvalue = dynamic_cast<const OperationParameterValue *>(
+            genOpParamvalue.get());
+        if (opParamvalue) {
+            const auto &parameter = opParamvalue->parameter();
+            if (!getMapping(methodMapping, parameter)) {
+                std::string msg("Parameter ");
+                msg += parameter->nameStr();
+                msg += " found but not expected for this method";
+                res.emplace_back(msg);
+            }
+        }
+    }
+
+    return res;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct ParameterValue::Private {
+    ParameterValue::Type type_{ParameterValue::Type::STRING};
+    std::unique_ptr<common::Measure> measure_{};
+    std::unique_ptr<std::string> stringValue_{};
+    int integerValue_{};
+    bool booleanValue_{};
+
+    explicit Private(const common::Measure &valueIn)
+        : type_(ParameterValue::Type::MEASURE),
+          measure_(internal::make_unique<common::Measure>(valueIn)) {}
+
+    Private(const std::string &stringValueIn, ParameterValue::Type typeIn)
+        : type_(typeIn),
+          stringValue_(internal::make_unique<std::string>(stringValueIn)) {}
+
+    explicit Private(int integerValueIn)
+        : type_(ParameterValue::Type::INTEGER), integerValue_(integerValueIn) {}
+
+    explicit Private(bool booleanValueIn)
+        : type_(ParameterValue::Type::BOOLEAN), booleanValue_(booleanValueIn) {}
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+ParameterValue::~ParameterValue() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+ParameterValue::ParameterValue(const common::Measure &measureIn)
+    : d(internal::make_unique<Private>(measureIn)) {}
+
+// ---------------------------------------------------------------------------
+
+ParameterValue::ParameterValue(const std::string &stringValueIn,
+                               ParameterValue::Type typeIn)
+    : d(internal::make_unique<Private>(stringValueIn, typeIn)) {}
+
+// ---------------------------------------------------------------------------
+
+ParameterValue::ParameterValue(int integerValueIn)
+    : d(internal::make_unique<Private>(integerValueIn)) {}
+
+// ---------------------------------------------------------------------------
+
+ParameterValue::ParameterValue(bool booleanValueIn)
+    : d(internal::make_unique<Private>(booleanValueIn)) {}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ParameterValue from a Measure (i.e. a value associated
+ * with a
+ * unit)
+ *
+ * @return a new ParameterValue.
+ */
+ParameterValueNNPtr ParameterValue::create(const common::Measure &measureIn) {
+    return ParameterValue::nn_make_shared<ParameterValue>(measureIn);
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ParameterValue from a string value.
+ *
+ * @return a new ParameterValue.
+ */
+ParameterValueNNPtr ParameterValue::create(const char *stringValueIn) {
+    return ParameterValue::nn_make_shared<ParameterValue>(
+        std::string(stringValueIn), ParameterValue::Type::STRING);
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ParameterValue from a string value.
+ *
+ * @return a new ParameterValue.
+ */
+ParameterValueNNPtr ParameterValue::create(const std::string &stringValueIn) {
+    return ParameterValue::nn_make_shared<ParameterValue>(
+        stringValueIn, ParameterValue::Type::STRING);
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ParameterValue from a filename.
+ *
+ * @return a new ParameterValue.
+ */
+ParameterValueNNPtr
+ParameterValue::createFilename(const std::string &stringValueIn) {
+    return ParameterValue::nn_make_shared<ParameterValue>(
+        stringValueIn, ParameterValue::Type::FILENAME);
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ParameterValue from a integer value.
+ *
+ * @return a new ParameterValue.
+ */
+ParameterValueNNPtr ParameterValue::create(int integerValueIn) {
+    return ParameterValue::nn_make_shared<ParameterValue>(integerValueIn);
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ParameterValue from a boolean value.
+ *
+ * @return a new ParameterValue.
+ */
+ParameterValueNNPtr ParameterValue::create(bool booleanValueIn) {
+    return ParameterValue::nn_make_shared<ParameterValue>(booleanValueIn);
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns the type of a parameter value.
+ *
+ * @return the type.
+ */
+const ParameterValue::Type &ParameterValue::type() PROJ_CONST_DEFN {
+    return d->type_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns the value as a Measure (assumes type() == Type::MEASURE)
+ * @return the value as a Measure.
+ */
+const common::Measure &ParameterValue::value() PROJ_CONST_DEFN {
+    return *d->measure_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns the value as a string (assumes type() == Type::STRING)
+ * @return the value as a string.
+ */
+const std::string &ParameterValue::stringValue() PROJ_CONST_DEFN {
+    return *d->stringValue_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns the value as a filename (assumes type() == Type::FILENAME)
+ * @return the value as a filename.
+ */
+const std::string &ParameterValue::valueFile() PROJ_CONST_DEFN {
+    return *d->stringValue_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns the value as a integer (assumes type() == Type::INTEGER)
+ * @return the value as a integer.
+ */
+int ParameterValue::integerValue() PROJ_CONST_DEFN { return d->integerValue_; }
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns the value as a boolean (assumes type() == Type::BOOLEAN)
+ * @return the value as a boolean.
+ */
+bool ParameterValue::booleanValue() PROJ_CONST_DEFN { return d->booleanValue_; }
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void ParameterValue::_exportToWKT(io::WKTFormatter *formatter) const {
+    const bool isWKT2 = formatter->version() == io::WKTFormatter::Version::WKT2;
+
+    const auto &l_type = type();
+    const auto &l_value = value();
+    if (formatter->abridgedTransformation() && l_type == Type::MEASURE) {
+        const auto &unit = l_value.unit();
+        const auto &unitType = unit.type();
+        if (unitType == common::UnitOfMeasure::Type::LINEAR) {
+            formatter->add(l_value.getSIValue());
+        } else if (unitType == common::UnitOfMeasure::Type::ANGULAR) {
+            formatter->add(
+                l_value.convertToUnit(common::UnitOfMeasure::ARC_SECOND));
+        } else if (unit == common::UnitOfMeasure::PARTS_PER_MILLION) {
+            formatter->add(1.0 + l_value.value() * 1e-6);
+        } else {
+            formatter->add(l_value.value());
+        }
+    } else if (l_type == Type::MEASURE) {
+        const auto &unit = l_value.unit();
+        if (isWKT2) {
+            formatter->add(l_value.value());
+        } else {
+            // In WKT1, as we don't output the natural unit, output to the
+            // registered linear / angular unit.
+            const auto &unitType = unit.type();
+            if (unitType == common::UnitOfMeasure::Type::LINEAR) {
+                formatter->add(
+                    l_value.convertToUnit(*(formatter->axisLinearUnit())));
+            } else if (unitType == common::UnitOfMeasure::Type::ANGULAR) {
+                formatter->add(
+                    l_value.convertToUnit(*(formatter->axisAngularUnit())));
+            } else {
+                formatter->add(l_value.getSIValue());
+            }
+        }
+        if (isWKT2 && unit != common::UnitOfMeasure::NONE) {
+            if (!formatter->primeMeridianOrParameterUnitOmittedIfSameAsAxis() ||
+                (unit != common::UnitOfMeasure::SCALE_UNITY &&
+                 unit != *(formatter->axisLinearUnit()) &&
+                 unit != *(formatter->axisAngularUnit()))) {
+                unit._exportToWKT(formatter);
+            }
+        }
+    } else if (l_type == Type::STRING || l_type == Type::FILENAME) {
+        formatter->addQuotedString(stringValue());
+    } else if (l_type == Type::INTEGER) {
+        formatter->add(integerValue());
+    } else {
+        throw io::FormattingException("boolean parameter value not handled");
+    }
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+bool ParameterValue::_isEquivalentTo(
+    const util::IComparable *other,
+    util::IComparable::Criterion criterion) const {
+    auto otherPV = dynamic_cast<const ParameterValue *>(other);
+    if (otherPV == nullptr) {
+        return false;
+    }
+    if (type() != otherPV->type()) {
+        return false;
+    }
+    switch (type()) {
+    case Type::MEASURE: {
+        return value()._isEquivalentTo(otherPV->value(), criterion);
+    }
+
+    case Type::STRING:
+    case Type::FILENAME: {
+        return stringValue() == otherPV->stringValue();
+    }
+
+    case Type::INTEGER: {
+        return integerValue() == otherPV->integerValue();
+    }
+
+    case Type::BOOLEAN: {
+        return booleanValue() == otherPV->booleanValue();
+    }
+
+    default: {
+        assert(false);
+        break;
+    }
+    }
+    return true;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct Conversion::Private {};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+Conversion::Conversion(const OperationMethodNNPtr &methodIn,
+                       const std::vector<GeneralParameterValueNNPtr> &values)
+    : SingleOperation(methodIn), d(nullptr) {
+    setParameterValues(values);
+}
+
+// ---------------------------------------------------------------------------
+
+Conversion::Conversion(const Conversion &other)
+    : CoordinateOperation(other), SingleOperation(other), d(nullptr) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+Conversion::~Conversion() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+ConversionNNPtr Conversion::shallowClone() const {
+    auto conv = Conversion::nn_make_shared<Conversion>(*this);
+    conv->assignSelf(conv);
+    conv->setCRSs(this, false);
+    return conv;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+ConversionNNPtr
+Conversion::alterParametersLinearUnit(const common::UnitOfMeasure &unit,
+                                      bool convertToNewUnit) const {
+
+    std::vector<GeneralParameterValueNNPtr> newValues;
+    bool changesDone = false;
+    for (const auto &genOpParamvalue : parameterValues()) {
+        bool updated = false;
+        auto opParamvalue = dynamic_cast<const OperationParameterValue *>(
+            genOpParamvalue.get());
+        if (opParamvalue) {
+            const auto &paramValue = opParamvalue->parameterValue();
+            if (paramValue->type() == ParameterValue::Type::MEASURE) {
+                const auto &measure = paramValue->value();
+                if (measure.unit().type() ==
+                    common::UnitOfMeasure::Type::LINEAR) {
+                    if (!measure.unit()._isEquivalentTo(
+                            unit, util::IComparable::Criterion::EQUIVALENT)) {
+                        const double newValue =
+                            convertToNewUnit ? measure.convertToUnit(unit)
+                                             : measure.value();
+                        newValues.emplace_back(OperationParameterValue::create(
+                            opParamvalue->parameter(),
+                            ParameterValue::create(
+                                common::Measure(newValue, unit))));
+                        updated = true;
+                    }
+                }
+            }
+        }
+        if (updated) {
+            changesDone = true;
+        } else {
+            newValues.emplace_back(genOpParamvalue);
+        }
+    }
+    if (changesDone) {
+        auto conv = create(util::PropertyMap().set(
+                               common::IdentifiedObject::NAME_KEY, "unknown"),
+                           method(), newValues);
+        conv->setCRSs(this, false);
+        return conv;
+    } else {
+        return NN_NO_CHECK(
+            util::nn_dynamic_pointer_cast<Conversion>(shared_from_this()));
+    }
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a Conversion from a vector of GeneralParameterValue.
+ *
+ * @param properties See \ref general_properties. At minimum the name should be
+ * defined.
+ * @param methodIn the operation method.
+ * @param values the values.
+ * @return a new Conversion.
+ * @throws InvalidOperation
+ */
+ConversionNNPtr Conversion::create(const util::PropertyMap &properties,
+                                   const OperationMethodNNPtr &methodIn,
+                                   const std::vector<GeneralParameterValueNNPtr>
+                                       &values) // throw InvalidOperation
+{
+    if (methodIn->parameters().size() != values.size()) {
+        throw InvalidOperation(
+            "Inconsistent number of parameters and parameter values");
+    }
+    auto conv = Conversion::nn_make_shared<Conversion>(methodIn, values);
+    conv->assignSelf(conv);
+    conv->setProperties(properties);
+    return conv;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a Conversion and its OperationMethod
+ *
+ * @param propertiesConversion See \ref general_properties of the conversion.
+ * At minimum the name should be defined.
+ * @param propertiesOperationMethod See \ref general_properties of the operation
+ * method. At minimum the name should be defined.
+ * @param parameters the operation parameters.
+ * @param values the operation values. Constraint:
+ * values.size() == parameters.size()
+ * @return a new Conversion.
+ * @throws InvalidOperation
+ */
+ConversionNNPtr Conversion::create(
+    const util::PropertyMap &propertiesConversion,
+    const util::PropertyMap &propertiesOperationMethod,
+    const std::vector<OperationParameterNNPtr> &parameters,
+    const std::vector<ParameterValueNNPtr> &values) // throw InvalidOperation
+{
+    OperationMethodNNPtr op(
+        OperationMethod::create(propertiesOperationMethod, parameters));
+
+    if (parameters.size() != values.size()) {
+        throw InvalidOperation(
+            "Inconsistent number of parameters and parameter values");
+    }
+    std::vector<GeneralParameterValueNNPtr> generalParameterValues;
+    generalParameterValues.reserve(values.size());
+    for (size_t i = 0; i < values.size(); i++) {
+        generalParameterValues.push_back(
+            OperationParameterValue::create(parameters[i], values[i]));
+    }
+    return create(propertiesConversion, op, generalParameterValues);
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+// ---------------------------------------------------------------------------
+
+static util::PropertyMap createMapNameEPSGCode(const std::string &name,
+                                               int code) {
+    return util::PropertyMap()
+        .set(common::IdentifiedObject::NAME_KEY, name)
+        .set(metadata::Identifier::CODESPACE_KEY, metadata::Identifier::EPSG)
+        .set(metadata::Identifier::CODE_KEY, code);
+}
+
+// ---------------------------------------------------------------------------
+
+static util::PropertyMap createMapNameEPSGCode(const char *name, int code) {
+    return util::PropertyMap()
+        .set(common::IdentifiedObject::NAME_KEY, name)
+        .set(metadata::Identifier::CODESPACE_KEY, metadata::Identifier::EPSG)
+        .set(metadata::Identifier::CODE_KEY, code);
+}
+
+// ---------------------------------------------------------------------------
+
+static util::PropertyMap createMethodMapNameEPSGCode(int code) {
+    const char *name = nullptr;
+    for (const auto &tuple : methodNameCodes) {
+        if (tuple.epsg_code == code) {
+            name = tuple.name;
+            break;
+        }
+    }
+    assert(name);
+    return createMapNameEPSGCode(name, code);
+}
+
+// ---------------------------------------------------------------------------
+
+static util::PropertyMap
+getUTMConversionProperty(const util::PropertyMap &properties, int zone,
+                         bool north) {
+    if (!properties.get(common::IdentifiedObject::NAME_KEY)) {
+        std::string conversionName("UTM zone ");
+        conversionName += toString(zone);
+        conversionName += (north ? 'N' : 'S');
+
+        return createMapNameEPSGCode(conversionName,
+                                     (north ? 16000 : 17000) + zone);
+    } else {
+        return properties;
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+static util::PropertyMap
+addDefaultNameIfNeeded(const util::PropertyMap &properties,
+                       const std::string &defaultName) {
+    if (!properties.get(common::IdentifiedObject::NAME_KEY)) {
+        return util::PropertyMap(properties)
+            .set(common::IdentifiedObject::NAME_KEY, defaultName);
+    } else {
+        return properties;
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+static ConversionNNPtr
+createConversion(const util::PropertyMap &properties,
+                 const MethodMapping *mapping,
+                 const std::vector<ParameterValueNNPtr> &values) {
+
+    std::vector<OperationParameterNNPtr> parameters;
+    for (int i = 0; mapping->params[i] != nullptr; i++) {
+        const auto *param = mapping->params[i];
+        auto paramProperties = util::PropertyMap().set(
+            common::IdentifiedObject::NAME_KEY, param->wkt2_name);
+        if (param->epsg_code != 0) {
+            paramProperties
+                .set(metadata::Identifier::CODESPACE_KEY,
+                     metadata::Identifier::EPSG)
+                .set(metadata::Identifier::CODE_KEY, param->epsg_code);
+        }
+        auto parameter = OperationParameter::create(paramProperties);
+        parameters.push_back(parameter);
+    }
+
+    auto methodProperties = util::PropertyMap().set(
+        common::IdentifiedObject::NAME_KEY, mapping->wkt2_name);
+    if (mapping->epsg_code != 0) {
+        methodProperties
+            .set(metadata::Identifier::CODESPACE_KEY,
+                 metadata::Identifier::EPSG)
+            .set(metadata::Identifier::CODE_KEY, mapping->epsg_code);
+    }
+    return Conversion::create(
+        addDefaultNameIfNeeded(properties, mapping->wkt2_name),
+        methodProperties, parameters, values);
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+ConversionNNPtr
+Conversion::create(const util::PropertyMap &properties, int method_epsg_code,
+                   const std::vector<ParameterValueNNPtr> &values) {
+    const MethodMapping *mapping = getMapping(method_epsg_code);
+    assert(mapping);
+    return createConversion(properties, mapping, values);
+}
+
+// ---------------------------------------------------------------------------
+
+ConversionNNPtr
+Conversion::create(const util::PropertyMap &properties,
+                   const char *method_wkt2_name,
+                   const std::vector<ParameterValueNNPtr> &values) {
+    const MethodMapping *mapping = getMapping(method_wkt2_name);
+    assert(mapping);
+    return createConversion(properties, mapping, values);
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+struct VectorOfParameters : public std::vector<OperationParameterNNPtr> {
+    VectorOfParameters() : std::vector<OperationParameterNNPtr>() {}
+    explicit VectorOfParameters(
+        std::initializer_list<OperationParameterNNPtr> list)
+        : std::vector<OperationParameterNNPtr>(list) {}
+    VectorOfParameters(const VectorOfParameters &) = delete;
+
+    ~VectorOfParameters();
+};
+
+// This way, we disable inlining of destruction, and save a lot of space
+VectorOfParameters::~VectorOfParameters() = default;
+
+struct VectorOfValues : public std::vector<ParameterValueNNPtr> {
+    VectorOfValues() : std::vector<ParameterValueNNPtr>() {}
+    explicit VectorOfValues(std::initializer_list<ParameterValueNNPtr> list)
+        : std::vector<ParameterValueNNPtr>(list) {}
+
+    explicit VectorOfValues(std::initializer_list<common::Measure> list);
+    VectorOfValues(const VectorOfValues &) = delete;
+    VectorOfValues(VectorOfValues &&) = default;
+
+    ~VectorOfValues();
+};
+
+static std::vector<ParameterValueNNPtr> buildParameterValueFromMeasure(
+    const std::initializer_list<common::Measure> &list) {
+    std::vector<ParameterValueNNPtr> res;
+    for (const auto &v : list) {
+        res.emplace_back(ParameterValue::create(v));
+    }
+    return res;
+}
+
+VectorOfValues::VectorOfValues(std::initializer_list<common::Measure> list)
+    : std::vector<ParameterValueNNPtr>(buildParameterValueFromMeasure(list)) {}
+
+// This way, we disable inlining of destruction, and save a lot of space
+VectorOfValues::~VectorOfValues() = default;
+
+PROJ_NO_INLINE static VectorOfValues createParams(const common::Measure &m1,
+                                                  const common::Measure &m2,
+                                                  const common::Measure &m3) {
+    return VectorOfValues{ParameterValue::create(m1),
+                          ParameterValue::create(m2),
+                          ParameterValue::create(m3)};
+}
+
+PROJ_NO_INLINE static VectorOfValues createParams(const common::Measure &m1,
+                                                  const common::Measure &m2,
+                                                  const common::Measure &m3,
+                                                  const common::Measure &m4) {
+    return VectorOfValues{
+        ParameterValue::create(m1), ParameterValue::create(m2),
+        ParameterValue::create(m3), ParameterValue::create(m4)};
+}
+
+PROJ_NO_INLINE static VectorOfValues createParams(const common::Measure &m1,
+                                                  const common::Measure &m2,
+                                                  const common::Measure &m3,
+                                                  const common::Measure &m4,
+                                                  const common::Measure &m5) {
+    return VectorOfValues{
+        ParameterValue::create(m1), ParameterValue::create(m2),
+        ParameterValue::create(m3), ParameterValue::create(m4),
+        ParameterValue::create(m5),
+    };
+}
+
+PROJ_NO_INLINE static VectorOfValues
+createParams(const common::Measure &m1, const common::Measure &m2,
+             const common::Measure &m3, const common::Measure &m4,
+             const common::Measure &m5, const common::Measure &m6) {
+    return VectorOfValues{
+        ParameterValue::create(m1), ParameterValue::create(m2),
+        ParameterValue::create(m3), ParameterValue::create(m4),
+        ParameterValue::create(m5), ParameterValue::create(m6),
+    };
+}
+
+PROJ_NO_INLINE static VectorOfValues
+createParams(const common::Measure &m1, const common::Measure &m2,
+             const common::Measure &m3, const common::Measure &m4,
+             const common::Measure &m5, const common::Measure &m6,
+             const common::Measure &m7) {
+    return VectorOfValues{
+        ParameterValue::create(m1), ParameterValue::create(m2),
+        ParameterValue::create(m3), ParameterValue::create(m4),
+        ParameterValue::create(m5), ParameterValue::create(m6),
+        ParameterValue::create(m7),
+    };
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a [Universal Transverse Mercator]
+ *(https://proj4.org/operations/projections/utm.html) conversion.
+ *
+ * UTM is a family of conversions, of EPSG codes from 16001 to 16060 for the
+ * northern hemisphere, and 17001 to 17060 for the southern hemisphere,
+ * based on the Transverse Mercator projection method.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param zone UTM zone number between 1 and 60.
+ * @param north true for UTM northern hemisphere, false for UTM southern
+ * hemisphere.
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createUTM(const util::PropertyMap &properties,
+                                      int zone, bool north) {
+    return create(
+        getUTMConversionProperty(properties, zone, north),
+        EPSG_CODE_METHOD_TRANSVERSE_MERCATOR,
+        createParams(common::Angle(UTM_LATITUDE_OF_NATURAL_ORIGIN),
+                     common::Angle(zone * 6.0 - 183.0),
+                     common::Scale(UTM_SCALE_FACTOR),
+                     common::Length(UTM_FALSE_EASTING),
+                     common::Length(north ? UTM_NORTH_FALSE_NORTHING
+                                          : UTM_SOUTH_FALSE_NORTHING)));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Transverse Mercator]
+ *(https://proj4.org/operations/projections/tmerc.html) projection method.
+ *
+ * This method is defined as [EPSG:9807]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9807)
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLat See \ref center_latitude
+ * @param centerLong See \ref center_longitude
+ * @param scale See \ref scale
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createTransverseMercator(
+    const util::PropertyMap &properties, const common::Angle &centerLat,
+    const common::Angle &centerLong, const common::Scale &scale,
+    const common::Length &falseEasting, const common::Length &falseNorthing) {
+    return create(properties, EPSG_CODE_METHOD_TRANSVERSE_MERCATOR,
+                  createParams(centerLat, centerLong, scale, falseEasting,
+                               falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Gauss Schreiber Transverse
+ *Mercator]
+ *(https://proj4.org/operations/projections/gstmerc.html) projection method.
+ *
+ * This method is also known as Gauss-Laborde Reunion.
+ *
+ * There is no equivalent in EPSG.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLat See \ref center_latitude
+ * @param centerLong See \ref center_longitude
+ * @param scale See \ref scale
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createGaussSchreiberTransverseMercator(
+    const util::PropertyMap &properties, const common::Angle &centerLat,
+    const common::Angle &centerLong, const common::Scale &scale,
+    const common::Length &falseEasting, const common::Length &falseNorthing) {
+    return create(properties,
+                  PROJ_WKT2_NAME_METHOD_GAUSS_SCHREIBER_TRANSVERSE_MERCATOR,
+                  createParams(centerLat, centerLong, scale, falseEasting,
+                               falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Transverse Mercator South
+ *Orientated]
+ *(https://proj4.org/operations/projections/tmerc.html) projection method.
+ *
+ * This method is defined as [EPSG:9808]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9808)
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLat See \ref center_latitude
+ * @param centerLong See \ref center_longitude
+ * @param scale See \ref scale
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createTransverseMercatorSouthOriented(
+    const util::PropertyMap &properties, const common::Angle &centerLat,
+    const common::Angle &centerLong, const common::Scale &scale,
+    const common::Length &falseEasting, const common::Length &falseNorthing) {
+    return create(properties,
+                  EPSG_CODE_METHOD_TRANSVERSE_MERCATOR_SOUTH_ORIENTATED,
+                  createParams(centerLat, centerLong, scale, falseEasting,
+                               falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the  [Two Point Equidistant]
+ *(https://proj4.org/operations/projections/tpeqd.html) projection method.
+ *
+ * There is no equivalent in EPSG.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param latitudeFirstPoint Latitude of first point.
+ * @param longitudeFirstPoint Longitude of first point.
+ * @param latitudeSecondPoint Latitude of second point.
+ * @param longitudeSeconPoint Longitude of second point.
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr
+Conversion::createTwoPointEquidistant(const util::PropertyMap &properties,
+                                      const common::Angle &latitudeFirstPoint,
+                                      const common::Angle &longitudeFirstPoint,
+                                      const common::Angle &latitudeSecondPoint,
+                                      const common::Angle &longitudeSeconPoint,
+                                      const common::Length &falseEasting,
+                                      const common::Length &falseNorthing) {
+    return create(properties, PROJ_WKT2_NAME_METHOD_TWO_POINT_EQUIDISTANT,
+                  createParams(latitudeFirstPoint, longitudeFirstPoint,
+                               latitudeSecondPoint, longitudeSeconPoint,
+                               falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the Tunisia Mapping Grid projection
+ * method.
+ *
+ * This method is defined as [EPSG:9816]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9816)
+ *
+ * \note There is currently no implementation of the method formulas in PROJ.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLat See \ref center_latitude
+ * @param centerLong See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createTunisiaMappingGrid(
+    const util::PropertyMap &properties, const common::Angle &centerLat,
+    const common::Angle &centerLong, const common::Length &falseEasting,
+    const common::Length &falseNorthing) {
+    return create(
+        properties, EPSG_CODE_METHOD_TUNISIA_MAPPING_GRID,
+        createParams(centerLat, centerLong, falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Albers Conic Equal Area]
+ *(https://proj4.org/operations/projections/aea.html) projection method.
+ *
+ * This method is defined as [EPSG:9822]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9822)
+ *
+ * @note the order of arguments is conformant with the corresponding EPSG
+ * mode and different than OGRSpatialReference::setACEA() of GDAL &lt;= 2.3
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param latitudeFalseOrigin See \ref latitude_false_origin
+ * @param longitudeFalseOrigin See \ref longitude_false_origin
+ * @param latitudeFirstParallel See \ref latitude_first_std_parallel
+ * @param latitudeSecondParallel See \ref latitude_second_std_parallel
+ * @param eastingFalseOrigin See \ref easting_false_origin
+ * @param northingFalseOrigin See \ref northing_false_origin
+ * @return a new Conversion.
+ */
+ConversionNNPtr
+Conversion::createAlbersEqualArea(const util::PropertyMap &properties,
+                                  const common::Angle &latitudeFalseOrigin,
+                                  const common::Angle &longitudeFalseOrigin,
+                                  const common::Angle &latitudeFirstParallel,
+                                  const common::Angle &latitudeSecondParallel,
+                                  const common::Length &eastingFalseOrigin,
+                                  const common::Length &northingFalseOrigin) {
+    return create(properties, EPSG_CODE_METHOD_ALBERS_EQUAL_AREA,
+                  createParams(latitudeFalseOrigin, longitudeFalseOrigin,
+                               latitudeFirstParallel, latitudeSecondParallel,
+                               eastingFalseOrigin, northingFalseOrigin));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Lambert Conic Conformal 1SP]
+ *(https://proj4.org/operations/projections/lcc.html) projection method.
+ *
+ * This method is defined as [EPSG:9801]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9801)
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLat See \ref center_latitude
+ * @param centerLong See \ref center_longitude
+ * @param scale See \ref scale
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createLambertConicConformal_1SP(
+    const util::PropertyMap &properties, const common::Angle &centerLat,
+    const common::Angle &centerLong, const common::Scale &scale,
+    const common::Length &falseEasting, const common::Length &falseNorthing) {
+    return create(properties, EPSG_CODE_METHOD_LAMBERT_CONIC_CONFORMAL_1SP,
+                  createParams(centerLat, centerLong, scale, falseEasting,
+                               falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Lambert Conic Conformal (2SP)]
+ *(https://proj4.org/operations/projections/lcc.html) projection method.
+ *
+ * This method is defined as [EPSG:9802]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9802)
+ *
+ * @note the order of arguments is conformant with the corresponding EPSG
+ * mode and different than OGRSpatialReference::setLCC() of GDAL &lt;= 2.3
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param latitudeFalseOrigin See \ref latitude_false_origin
+ * @param longitudeFalseOrigin See \ref longitude_false_origin
+ * @param latitudeFirstParallel See \ref latitude_first_std_parallel
+ * @param latitudeSecondParallel See \ref latitude_second_std_parallel
+ * @param eastingFalseOrigin See \ref easting_false_origin
+ * @param northingFalseOrigin See \ref northing_false_origin
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createLambertConicConformal_2SP(
+    const util::PropertyMap &properties,
+    const common::Angle &latitudeFalseOrigin,
+    const common::Angle &longitudeFalseOrigin,
+    const common::Angle &latitudeFirstParallel,
+    const common::Angle &latitudeSecondParallel,
+    const common::Length &eastingFalseOrigin,
+    const common::Length &northingFalseOrigin) {
+    return create(properties, EPSG_CODE_METHOD_LAMBERT_CONIC_CONFORMAL_2SP,
+                  createParams(latitudeFalseOrigin, longitudeFalseOrigin,
+                               latitudeFirstParallel, latitudeSecondParallel,
+                               eastingFalseOrigin, northingFalseOrigin));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Lambert Conic Conformal (2SP
+ *Michigan)]
+ *(https://proj4.org/operations/projections/lcc.html) projection method.
+ *
+ * This method is defined as [EPSG:1051]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::1051)
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param latitudeFalseOrigin See \ref latitude_false_origin
+ * @param longitudeFalseOrigin See \ref longitude_false_origin
+ * @param latitudeFirstParallel See \ref latitude_first_std_parallel
+ * @param latitudeSecondParallel See \ref latitude_second_std_parallel
+ * @param eastingFalseOrigin See \ref easting_false_origin
+ * @param northingFalseOrigin See \ref northing_false_origin
+ * @param ellipsoidScalingFactor Ellipsoid scaling factor.
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createLambertConicConformal_2SP_Michigan(
+    const util::PropertyMap &properties,
+    const common::Angle &latitudeFalseOrigin,
+    const common::Angle &longitudeFalseOrigin,
+    const common::Angle &latitudeFirstParallel,
+    const common::Angle &latitudeSecondParallel,
+    const common::Length &eastingFalseOrigin,
+    const common::Length &northingFalseOrigin,
+    const common::Scale &ellipsoidScalingFactor) {
+    return create(properties,
+                  EPSG_CODE_METHOD_LAMBERT_CONIC_CONFORMAL_2SP_MICHIGAN,
+                  createParams(latitudeFalseOrigin, longitudeFalseOrigin,
+                               latitudeFirstParallel, latitudeSecondParallel,
+                               eastingFalseOrigin, northingFalseOrigin,
+                               ellipsoidScalingFactor));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Lambert Conic Conformal (2SP
+ *Belgium)]
+ *(https://proj4.org/operations/projections/lcc.html) projection method.
+ *
+ * This method is defined as [EPSG:9803]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9803)
+ *
+ * \warning The formulas used currently in PROJ are, incorrectly, the ones of
+ * the regular LCC_2SP method.
+ *
+ * @note the order of arguments is conformant with the corresponding EPSG
+ * mode and different than OGRSpatialReference::setLCCB() of GDAL &lt;= 2.3
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param latitudeFalseOrigin See \ref latitude_false_origin
+ * @param longitudeFalseOrigin See \ref longitude_false_origin
+ * @param latitudeFirstParallel See \ref latitude_first_std_parallel
+ * @param latitudeSecondParallel See \ref latitude_second_std_parallel
+ * @param eastingFalseOrigin See \ref easting_false_origin
+ * @param northingFalseOrigin See \ref northing_false_origin
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createLambertConicConformal_2SP_Belgium(
+    const util::PropertyMap &properties,
+    const common::Angle &latitudeFalseOrigin,
+    const common::Angle &longitudeFalseOrigin,
+    const common::Angle &latitudeFirstParallel,
+    const common::Angle &latitudeSecondParallel,
+    const common::Length &eastingFalseOrigin,
+    const common::Length &northingFalseOrigin) {
+
+    return create(properties,
+                  EPSG_CODE_METHOD_LAMBERT_CONIC_CONFORMAL_2SP_BELGIUM,
+                  createParams(latitudeFalseOrigin, longitudeFalseOrigin,
+                               latitudeFirstParallel, latitudeSecondParallel,
+                               eastingFalseOrigin, northingFalseOrigin));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Modified Azimuthal
+ *Equidistant]
+ *(https://proj4.org/operations/projections/aeqd.html) projection method.
+ *
+ * This method is defined as [EPSG:9832]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9832)
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param latitudeNatOrigin See \ref center_latitude
+ * @param longitudeNatOrigin See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createAzimuthalEquidistant(
+    const util::PropertyMap &properties, const common::Angle &latitudeNatOrigin,
+    const common::Angle &longitudeNatOrigin, const common::Length &falseEasting,
+    const common::Length &falseNorthing) {
+    return create(properties, EPSG_CODE_METHOD_MODIFIED_AZIMUTHAL_EQUIDISTANT,
+                  createParams(latitudeNatOrigin, longitudeNatOrigin,
+                               falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Guam Projection]
+ *(https://proj4.org/operations/projections/aeqd.html) projection method.
+ *
+ * This method is defined as [EPSG:9831]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9831)
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ *is
+ * not provided, it is automatically set.
+ * @param latitudeNatOrigin See \ref center_latitude
+ * @param longitudeNatOrigin See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createGuamProjection(
+    const util::PropertyMap &properties, const common::Angle &latitudeNatOrigin,
+    const common::Angle &longitudeNatOrigin, const common::Length &falseEasting,
+    const common::Length &falseNorthing) {
+    return create(properties, EPSG_CODE_METHOD_GUAM_PROJECTION,
+                  createParams(latitudeNatOrigin, longitudeNatOrigin,
+                               falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Bonne]
+ *(https://proj4.org/operations/projections/bonne.html) projection method.
+ *
+ * This method is defined as [EPSG:9827]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9827)
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param latitudeNatOrigin See \ref center_latitude . PROJ calls its the
+ * standard parallel 1.
+ * @param longitudeNatOrigin See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createBonne(const util::PropertyMap &properties,
+                                        const common::Angle &latitudeNatOrigin,
+                                        const common::Angle &longitudeNatOrigin,
+                                        const common::Length &falseEasting,
+                                        const common::Length &falseNorthing) {
+    return create(properties, EPSG_CODE_METHOD_BONNE,
+                  createParams(latitudeNatOrigin, longitudeNatOrigin,
+                               falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Lambert Cylindrical Equal Area
+ *(Spherical)]
+ *(https://proj4.org/operations/projections/cea.html) projection method.
+ *
+ * This method is defined as [EPSG:9834]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9834)
+ *
+ * \warning The PROJ cea computation code would select the ellipsoidal form if
+ * a non-spherical ellipsoid is used for the base GeographicalCRS.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param latitudeFirstParallel See \ref latitude_first_std_parallel.
+ * @param longitudeNatOrigin See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createLambertCylindricalEqualAreaSpherical(
+    const util::PropertyMap &properties,
+    const common::Angle &latitudeFirstParallel,
+    const common::Angle &longitudeNatOrigin, const common::Length &falseEasting,
+    const common::Length &falseNorthing) {
+    return create(properties,
+                  EPSG_CODE_METHOD_LAMBERT_CYLINDRICAL_EQUAL_AREA_SPHERICAL,
+                  createParams(latitudeFirstParallel, longitudeNatOrigin,
+                               falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Lambert Cylindrical Equal Area
+ *(ellipsoidal form)]
+ *(https://proj4.org/operations/projections/cea.html) projection method.
+ *
+ * This method is defined as [EPSG:9835]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9835)
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param latitudeFirstParallel See \ref latitude_first_std_parallel.
+ * @param longitudeNatOrigin See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createLambertCylindricalEqualArea(
+    const util::PropertyMap &properties,
+    const common::Angle &latitudeFirstParallel,
+    const common::Angle &longitudeNatOrigin, const common::Length &falseEasting,
+    const common::Length &falseNorthing) {
+    return create(properties, EPSG_CODE_METHOD_LAMBERT_CYLINDRICAL_EQUAL_AREA,
+                  createParams(latitudeFirstParallel, longitudeNatOrigin,
+                               falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Cassini-Soldner]
+ * (https://proj4.org/operations/projections/cass.html) projection method.
+ *
+ * This method is defined as [EPSG:9806]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9806)
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLat See \ref center_latitude
+ * @param centerLong See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createCassiniSoldner(
+    const util::PropertyMap &properties, const common::Angle &centerLat,
+    const common::Angle &centerLong, const common::Length &falseEasting,
+    const common::Length &falseNorthing) {
+    return create(
+        properties, EPSG_CODE_METHOD_CASSINI_SOLDNER,
+        createParams(centerLat, centerLong, falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Equidistant Conic]
+ *(https://proj4.org/operations/projections/eqdc.html) projection method.
+ *
+ * There is no equivalent in EPSG.
+ *
+ * @note Although not found in EPSG, the order of arguments is conformant with
+ * the "spirit" of EPSG and different than OGRSpatialReference::setEC() of GDAL
+ *&lt;= 2.3 * @param properties See \ref general_properties of the conversion.
+ *If the name
+ * is not provided, it is automatically set.
+ *
+ * @param centerLat See \ref center_latitude
+ * @param centerLong See \ref center_longitude
+ * @param latitudeFirstParallel See \ref latitude_first_std_parallel
+ * @param latitudeSecondParallel See \ref latitude_second_std_parallel
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createEquidistantConic(
+    const util::PropertyMap &properties, const common::Angle &centerLat,
+    const common::Angle &centerLong, const common::Angle &latitudeFirstParallel,
+    const common::Angle &latitudeSecondParallel,
+    const common::Length &falseEasting, const common::Length &falseNorthing) {
+    return create(properties, PROJ_WKT2_NAME_METHOD_EQUIDISTANT_CONIC,
+                  createParams(centerLat, centerLong, latitudeFirstParallel,
+                               latitudeSecondParallel, falseEasting,
+                               falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Eckert I]
+ * (https://proj4.org/operations/projections/eck1.html) projection method.
+ *
+ * There is no equivalent in EPSG.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLong See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createEckertI(const util::PropertyMap &properties,
+                                          const common::Angle &centerLong,
+                                          const common::Length &falseEasting,
+                                          const common::Length &falseNorthing) {
+    return create(properties, PROJ_WKT2_NAME_METHOD_ECKERT_I,
+                  createParams(centerLong, falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Eckert II]
+ * (https://proj4.org/operations/projections/eck2.html) projection method.
+ *
+ * There is no equivalent in EPSG.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLong See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createEckertII(
+    const util::PropertyMap &properties, const common::Angle &centerLong,
+    const common::Length &falseEasting, const common::Length &falseNorthing) {
+    return create(properties, PROJ_WKT2_NAME_METHOD_ECKERT_II,
+                  createParams(centerLong, falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Eckert III]
+ * (https://proj4.org/operations/projections/eck3.html) projection method.
+ *
+ * There is no equivalent in EPSG.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLong See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createEckertIII(
+    const util::PropertyMap &properties, const common::Angle &centerLong,
+    const common::Length &falseEasting, const common::Length &falseNorthing) {
+    return create(properties, PROJ_WKT2_NAME_METHOD_ECKERT_III,
+                  createParams(centerLong, falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Eckert IV]
+ * (https://proj4.org/operations/projections/eck4.html) projection method.
+ *
+ * There is no equivalent in EPSG.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLong See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createEckertIV(
+    const util::PropertyMap &properties, const common::Angle &centerLong,
+    const common::Length &falseEasting, const common::Length &falseNorthing) {
+    return create(properties, PROJ_WKT2_NAME_METHOD_ECKERT_IV,
+                  createParams(centerLong, falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Eckert V]
+ * (https://proj4.org/operations/projections/eck5.html) projection method.
+ *
+ * There is no equivalent in EPSG.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLong See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createEckertV(const util::PropertyMap &properties,
+                                          const common::Angle &centerLong,
+                                          const common::Length &falseEasting,
+                                          const common::Length &falseNorthing) {
+    return create(properties, PROJ_WKT2_NAME_METHOD_ECKERT_V,
+                  createParams(centerLong, falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Eckert VI]
+ * (https://proj4.org/operations/projections/eck6.html) projection method.
+ *
+ * There is no equivalent in EPSG.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLong See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createEckertVI(
+    const util::PropertyMap &properties, const common::Angle &centerLong,
+    const common::Length &falseEasting, const common::Length &falseNorthing) {
+    return create(properties, PROJ_WKT2_NAME_METHOD_ECKERT_VI,
+                  createParams(centerLong, falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Equidistant Cylindrical]
+ *(https://proj4.org/operations/projections/eqc.html) projection method.
+ *
+ * This is also known as the Equirectangular method, and in the particular case
+ * where the latitude of first parallel is 0.
+ *
+ * This method is defined as [EPSG:1028]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::1028)
+ *
+ * @note This is the equivalent OGRSpatialReference::SetEquirectangular2(
+ * 0.0, latitudeFirstParallel, falseEasting, falseNorthing ) of GDAL &lt;= 2.3,
+ * where the lat_0 / center_latitude parameter is forced to 0.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param latitudeFirstParallel See \ref latitude_first_std_parallel.
+ * @param longitudeNatOrigin See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createEquidistantCylindrical(
+    const util::PropertyMap &properties,
+    const common::Angle &latitudeFirstParallel,
+    const common::Angle &longitudeNatOrigin, const common::Length &falseEasting,
+    const common::Length &falseNorthing) {
+    return create(properties, EPSG_CODE_METHOD_EQUIDISTANT_CYLINDRICAL,
+                  createParams(latitudeFirstParallel, 0.0, longitudeNatOrigin,
+                               falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Equidistant Cylindrical
+ *(Spherical)]
+ *(https://proj4.org/operations/projections/eqc.html) projection method.
+ *
+ * This is also known as the Equirectangular method, and in the particular case
+ * where the latitude of first parallel is 0.
+ *
+ * This method is defined as [EPSG:1029]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::1029)
+ *
+ * @note This is the equivalent OGRSpatialReference::SetEquirectangular2(
+ * 0.0, latitudeFirstParallel, falseEasting, falseNorthing ) of GDAL &lt;= 2.3,
+ * where the lat_0 / center_latitude parameter is forced to 0.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param latitudeFirstParallel See \ref latitude_first_std_parallel.
+ * @param longitudeNatOrigin See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createEquidistantCylindricalSpherical(
+    const util::PropertyMap &properties,
+    const common::Angle &latitudeFirstParallel,
+    const common::Angle &longitudeNatOrigin, const common::Length &falseEasting,
+    const common::Length &falseNorthing) {
+    return create(properties,
+                  EPSG_CODE_METHOD_EQUIDISTANT_CYLINDRICAL_SPHERICAL,
+                  createParams(latitudeFirstParallel, 0.0, longitudeNatOrigin,
+                               falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Gall (Stereographic)]
+ * (https://proj4.org/operations/projections/gall.html) projection method.
+ *
+ * There is no equivalent in EPSG.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLong See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createGall(const util::PropertyMap &properties,
+                                       const common::Angle &centerLong,
+                                       const common::Length &falseEasting,
+                                       const common::Length &falseNorthing) {
+    return create(properties, PROJ_WKT2_NAME_METHOD_GALL_STEREOGRAPHIC,
+                  createParams(centerLong, falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Goode Homolosine]
+ * (https://proj4.org/operations/projections/goode.html) projection method.
+ *
+ * There is no equivalent in EPSG.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLong See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createGoodeHomolosine(
+    const util::PropertyMap &properties, const common::Angle &centerLong,
+    const common::Length &falseEasting, const common::Length &falseNorthing) {
+    return create(properties, PROJ_WKT2_NAME_METHOD_GOODE_HOMOLOSINE,
+                  createParams(centerLong, falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Interrupted Goode Homolosine]
+ * (https://proj4.org/operations/projections/igh.html) projection method.
+ *
+ * There is no equivalent in EPSG.
+ *
+ * @note OGRSpatialReference::SetIGH() of GDAL &lt;= 2.3 assumes the 3
+ * projection
+ * parameters to be zero and this is the nominal case.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLong See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createInterruptedGoodeHomolosine(
+    const util::PropertyMap &properties, const common::Angle &centerLong,
+    const common::Length &falseEasting, const common::Length &falseNorthing) {
+    return create(properties,
+                  PROJ_WKT2_NAME_METHOD_INTERRUPTED_GOODE_HOMOLOSINE,
+                  createParams(centerLong, falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Geostationary Satellite View]
+ * (https://proj4.org/operations/projections/geos.html) projection method,
+ * with the sweep angle axis of the viewing instrument being x
+ *
+ * There is no equivalent in EPSG.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLong See \ref center_longitude
+ * @param height Height of the view point above the Earth.
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createGeostationarySatelliteSweepX(
+    const util::PropertyMap &properties, const common::Angle &centerLong,
+    const common::Length &height, const common::Length &falseEasting,
+    const common::Length &falseNorthing) {
+    return create(
+        properties, PROJ_WKT2_NAME_METHOD_GEOSTATIONARY_SATELLITE_SWEEP_X,
+        createParams(centerLong, height, falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Geostationary Satellite View]
+ * (https://proj4.org/operations/projections/geos.html) projection method,
+ * with the sweep angle axis of the viewing instrument being y.
+ *
+ * There is no equivalent in EPSG.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLong See \ref center_longitude
+ * @param height Height of the view point above the Earth.
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createGeostationarySatelliteSweepY(
+    const util::PropertyMap &properties, const common::Angle &centerLong,
+    const common::Length &height, const common::Length &falseEasting,
+    const common::Length &falseNorthing) {
+    return create(
+        properties, PROJ_WKT2_NAME_METHOD_GEOSTATIONARY_SATELLITE_SWEEP_Y,
+        createParams(centerLong, height, falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Gnomonic]
+ *(https://proj4.org/operations/projections/gnom.html) projection method.
+ *
+ * There is no equivalent in EPSG.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLat See \ref center_latitude
+ * @param centerLong See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createGnomonic(
+    const util::PropertyMap &properties, const common::Angle &centerLat,
+    const common::Angle &centerLong, const common::Length &falseEasting,
+    const common::Length &falseNorthing) {
+    return create(
+        properties, PROJ_WKT2_NAME_METHOD_GNOMONIC,
+        createParams(centerLat, centerLong, falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Hotine Oblique Mercator
+ *(Variant A)]
+ *(https://proj4.org/operations/projections/omerc.html) projection method
+ *
+ * This is the variant with the no_uoff parameter, which corresponds to
+ * GDAL &gt;=2.3 Hotine_Oblique_Mercator projection.
+ * In this variant, the false grid coordinates are
+ * defined at the intersection of the initial line and the aposphere (the
+ * equator on one of the intermediate surfaces inherent in the method), that is
+ * at the natural origin of the coordinate system).
+ *
+ * This method is defined as [EPSG:9812]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9812)
+ *
+ * \note In the case where azimuthInitialLine = angleFromRectifiedToSkrewGrid =
+ *90deg,
+ * this maps to the  [Swiss Oblique Mercator]
+ *(https://proj4.org/operations/projections/somerc.html) formulas.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param latitudeProjectionCentre See \ref latitude_projection_centre
+ * @param longitudeProjectionCentre See \ref longitude_projection_centre
+ * @param azimuthInitialLine See \ref azimuth_initial_line
+ * @param angleFromRectifiedToSkrewGrid See
+ * \ref angle_from_recitfied_to_skrew_grid
+ * @param scale See \ref scale_factor_initial_line
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createHotineObliqueMercatorVariantA(
+    const util::PropertyMap &properties,
+    const common::Angle &latitudeProjectionCentre,
+    const common::Angle &longitudeProjectionCentre,
+    const common::Angle &azimuthInitialLine,
+    const common::Angle &angleFromRectifiedToSkrewGrid,
+    const common::Scale &scale, const common::Length &falseEasting,
+    const common::Length &falseNorthing) {
+    return create(
+        properties, EPSG_CODE_METHOD_HOTINE_OBLIQUE_MERCATOR_VARIANT_A,
+        createParams(latitudeProjectionCentre, longitudeProjectionCentre,
+                     azimuthInitialLine, angleFromRectifiedToSkrewGrid, scale,
+                     falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Hotine Oblique Mercator
+ *(Variant B)]
+ *(https://proj4.org/operations/projections/omerc.html) projection method
+ *
+ * This is the variant without the no_uoff parameter, which corresponds to
+ * GDAL &gt;=2.3 Hotine_Oblique_Mercator_Azimuth_Center projection.
+ * In this variant, the false grid coordinates are defined at the projection
+ *centre.
+ *
+ * This method is defined as [EPSG:9815]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9815)
+ *
+ * \note In the case where azimuthInitialLine = angleFromRectifiedToSkrewGrid =
+ *90deg,
+ * this maps to the  [Swiss Oblique Mercator]
+ *(https://proj4.org/operations/projections/somerc.html) formulas.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param latitudeProjectionCentre See \ref latitude_projection_centre
+ * @param longitudeProjectionCentre See \ref longitude_projection_centre
+ * @param azimuthInitialLine See \ref azimuth_initial_line
+ * @param angleFromRectifiedToSkrewGrid See
+ * \ref angle_from_recitfied_to_skrew_grid
+ * @param scale See \ref scale_factor_initial_line
+ * @param eastingProjectionCentre See \ref easting_projection_centre
+ * @param northingProjectionCentre See \ref northing_projection_centre
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createHotineObliqueMercatorVariantB(
+    const util::PropertyMap &properties,
+    const common::Angle &latitudeProjectionCentre,
+    const common::Angle &longitudeProjectionCentre,
+    const common::Angle &azimuthInitialLine,
+    const common::Angle &angleFromRectifiedToSkrewGrid,
+    const common::Scale &scale, const common::Length &eastingProjectionCentre,
+    const common::Length &northingProjectionCentre) {
+    return create(
+        properties, EPSG_CODE_METHOD_HOTINE_OBLIQUE_MERCATOR_VARIANT_B,
+        createParams(latitudeProjectionCentre, longitudeProjectionCentre,
+                     azimuthInitialLine, angleFromRectifiedToSkrewGrid, scale,
+                     eastingProjectionCentre, northingProjectionCentre));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Hotine Oblique Mercator Two
+ *Point Natural Origin]
+ *(https://proj4.org/operations/projections/omerc.html) projection method.
+ *
+ * There is no equivalent in EPSG.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param latitudeProjectionCentre See \ref latitude_projection_centre
+ * @param latitudePoint1 Latitude of point 1.
+ * @param longitudePoint1 Latitude of point 1.
+ * @param latitudePoint2 Latitude of point 2.
+ * @param longitudePoint2 Longitude of point 2.
+ * @param scale See \ref scale_factor_initial_line
+ * @param eastingProjectionCentre See \ref easting_projection_centre
+ * @param northingProjectionCentre See \ref northing_projection_centre
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createHotineObliqueMercatorTwoPointNaturalOrigin(
+    const util::PropertyMap &properties,
+    const common::Angle &latitudeProjectionCentre,
+    const common::Angle &latitudePoint1, const common::Angle &longitudePoint1,
+    const common::Angle &latitudePoint2, const common::Angle &longitudePoint2,
+    const common::Scale &scale, const common::Length &eastingProjectionCentre,
+    const common::Length &northingProjectionCentre) {
+    return create(
+        properties,
+        PROJ_WKT2_NAME_METHOD_HOTINE_OBLIQUE_MERCATOR_TWO_POINT_NATURAL_ORIGIN,
+        {
+            ParameterValue::create(latitudeProjectionCentre),
+            ParameterValue::create(latitudePoint1),
+            ParameterValue::create(longitudePoint1),
+            ParameterValue::create(latitudePoint2),
+            ParameterValue::create(longitudePoint2),
+            ParameterValue::create(scale),
+            ParameterValue::create(eastingProjectionCentre),
+            ParameterValue::create(northingProjectionCentre),
+        });
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Laborde Oblique Mercator]
+ *(https://proj4.org/operations/projections/labrd.html) projection method.
+ *
+ * This method is defined as [EPSG:9813]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9813)
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param latitudeProjectionCentre See \ref latitude_projection_centre
+ * @param longitudeProjectionCentre See \ref longitude_projection_centre
+ * @param azimuthInitialLine See \ref azimuth_initial_line
+ * @param scale See \ref scale_factor_initial_line
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createLabordeObliqueMercator(
+    const util::PropertyMap &properties,
+    const common::Angle &latitudeProjectionCentre,
+    const common::Angle &longitudeProjectionCentre,
+    const common::Angle &azimuthInitialLine, const common::Scale &scale,
+    const common::Length &falseEasting, const common::Length &falseNorthing) {
+    return create(properties, EPSG_CODE_METHOD_LABORDE_OBLIQUE_MERCATOR,
+                  createParams(latitudeProjectionCentre,
+                               longitudeProjectionCentre, azimuthInitialLine,
+                               scale, falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [International Map of the World
+ *Polyconic]
+ *(https://proj4.org/operations/projections/imw_p.html) projection method.
+ *
+ * There is no equivalent in EPSG.
+ *
+ * @note the order of arguments is conformant with the corresponding EPSG
+ * mode and different than OGRSpatialReference::SetIWMPolyconic() of GDAL &lt;=
+ *2.3
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLong See \ref center_longitude
+ * @param latitudeFirstParallel See \ref latitude_first_std_parallel
+ * @param latitudeSecondParallel See \ref latitude_second_std_parallel
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createInternationalMapWorldPolyconic(
+    const util::PropertyMap &properties, const common::Angle &centerLong,
+    const common::Angle &latitudeFirstParallel,
+    const common::Angle &latitudeSecondParallel,
+    const common::Length &falseEasting, const common::Length &falseNorthing) {
+    return create(properties, PROJ_WKT2_NAME_INTERNATIONAL_MAP_WORLD_POLYCONIC,
+                  createParams(centerLong, latitudeFirstParallel,
+                               latitudeSecondParallel, falseEasting,
+                               falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Krovak (north oriented)]
+ *(https://proj4.org/operations/projections/krovak.html) projection method.
+ *
+ * This method is defined as [EPSG:1041]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::1041)
+ *
+ * The coordinates are returned in the "GIS friendly" order: easting, northing.
+ * This method is similar to createKrovak(), except that the later returns
+ * projected values as southing, westing, where
+ * southing(Krovak) = -northing(Krovak_North) and
+ * westing(Krovak) = -easting(Krovak_North).
+ *
+ * @note The current PROJ implementation of Krovak hard-codes
+ * colatitudeConeAxis = 30deg17'17.30311"
+ * and latitudePseudoStandardParallel = 78deg30'N, which are the values used for
+ * the ProjectedCRS S-JTSK (Ferro) / Krovak East North (EPSG:5221).
+ * It also hard-codes the parameters of the Bessel ellipsoid typically used for
+ * Krovak.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param latitudeProjectionCentre See \ref latitude_projection_centre
+ * @param longitudeOfOrigin See \ref longitude_of_origin
+ * @param colatitudeConeAxis See \ref colatitude_cone_axis
+ * @param latitudePseudoStandardParallel See \ref
+ *latitude_pseudo_standard_parallel
+ * @param scaleFactorPseudoStandardParallel See \ref
+ *scale_factor_pseudo_standard_parallel
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createKrovakNorthOriented(
+    const util::PropertyMap &properties,
+    const common::Angle &latitudeProjectionCentre,
+    const common::Angle &longitudeOfOrigin,
+    const common::Angle &colatitudeConeAxis,
+    const common::Angle &latitudePseudoStandardParallel,
+    const common::Scale &scaleFactorPseudoStandardParallel,
+    const common::Length &falseEasting, const common::Length &falseNorthing) {
+    return create(properties, EPSG_CODE_METHOD_KROVAK_NORTH_ORIENTED,
+                  createParams(latitudeProjectionCentre, longitudeOfOrigin,
+                               colatitudeConeAxis,
+                               latitudePseudoStandardParallel,
+                               scaleFactorPseudoStandardParallel, falseEasting,
+                               falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Krovak]
+ *(https://proj4.org/operations/projections/krovak.html) projection method.
+ *
+ * This method is defined as [EPSG:9819]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9819)
+ *
+ * The coordinates are returned in the historical order: southing, westing
+ * This method is similar to createKrovakNorthOriented(), except that the later
+ *returns
+ * projected values as easting, northing, where
+ * easting(Krovak_North) = -westing(Krovak) and
+ * northing(Krovak_North) = -southing(Krovak).
+ *
+ * @note The current PROJ implementation of Krovak hard-codes
+ * colatitudeConeAxis = 30deg17'17.30311"
+ * and latitudePseudoStandardParallel = 78deg30'N, which are the values used for
+ * the ProjectedCRS S-JTSK (Ferro) / Krovak East North (EPSG:5221).
+ * It also hard-codes the parameters of the Bessel ellipsoid typically used for
+ * Krovak.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param latitudeProjectionCentre See \ref latitude_projection_centre
+ * @param longitudeOfOrigin See \ref longitude_of_origin
+ * @param colatitudeConeAxis See \ref colatitude_cone_axis
+ * @param latitudePseudoStandardParallel See \ref
+ *latitude_pseudo_standard_parallel
+ * @param scaleFactorPseudoStandardParallel See \ref
+ *scale_factor_pseudo_standard_parallel
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr
+Conversion::createKrovak(const util::PropertyMap &properties,
+                         const common::Angle &latitudeProjectionCentre,
+                         const common::Angle &longitudeOfOrigin,
+                         const common::Angle &colatitudeConeAxis,
+                         const common::Angle &latitudePseudoStandardParallel,
+                         const common::Scale &scaleFactorPseudoStandardParallel,
+                         const common::Length &falseEasting,
+                         const common::Length &falseNorthing) {
+    return create(properties, EPSG_CODE_METHOD_KROVAK,
+                  createParams(latitudeProjectionCentre, longitudeOfOrigin,
+                               colatitudeConeAxis,
+                               latitudePseudoStandardParallel,
+                               scaleFactorPseudoStandardParallel, falseEasting,
+                               falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Lambert Azimuthal Equal Area]
+ *(https://proj4.org/operations/projections/laea.html) projection method.
+ *
+ * This method is defined as [EPSG:9820]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9820)
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param latitudeNatOrigin See \ref center_latitude
+ * @param longitudeNatOrigin See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createLambertAzimuthalEqualArea(
+    const util::PropertyMap &properties, const common::Angle &latitudeNatOrigin,
+    const common::Angle &longitudeNatOrigin, const common::Length &falseEasting,
+    const common::Length &falseNorthing) {
+    return create(properties, EPSG_CODE_METHOD_LAMBERT_AZIMUTHAL_EQUAL_AREA,
+                  createParams(latitudeNatOrigin, longitudeNatOrigin,
+                               falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Miller Cylindrical]
+ *(https://proj4.org/operations/projections/mill.html) projection method.
+ *
+ * There is no equivalent in EPSG.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLong See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createMillerCylindrical(
+    const util::PropertyMap &properties, const common::Angle &centerLong,
+    const common::Length &falseEasting, const common::Length &falseNorthing) {
+    return create(properties, PROJ_WKT2_NAME_METHOD_MILLER_CYLINDRICAL,
+                  createParams(centerLong, falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Mercator]
+ *(https://proj4.org/operations/projections/merc.html) projection method.
+ *
+ * This is the variant, also known as Mercator (1SP), defined with the scale
+ * factor. Note that latitude of natural origin (centerLat) is a parameter,
+ * but unused in the transformation formulas.
+ *
+ * This method is defined as [EPSG:9804]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9804)
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLat See \ref center_latitude . Should be 0.
+ * @param centerLong See \ref center_longitude
+ * @param scale See \ref scale
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createMercatorVariantA(
+    const util::PropertyMap &properties, const common::Angle &centerLat,
+    const common::Angle &centerLong, const common::Scale &scale,
+    const common::Length &falseEasting, const common::Length &falseNorthing) {
+    return create(properties, EPSG_CODE_METHOD_MERCATOR_VARIANT_A,
+                  createParams(centerLat, centerLong, scale, falseEasting,
+                               falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Mercator]
+ *(https://proj4.org/operations/projections/merc.html) projection method.
+ *
+ * This is the variant, also known as Mercator (2SP), defined with the latitude
+ * of the first standard parallel (the second standard parallel is implicitly
+ * the opposite value). The latitude of natural origin is fixed to zero.
+ *
+ * This method is defined as [EPSG:9805]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9805)
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param latitudeFirstParallel See \ref latitude_first_std_parallel
+ * @param centerLong See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createMercatorVariantB(
+    const util::PropertyMap &properties,
+    const common::Angle &latitudeFirstParallel, const common::Angle &centerLong,
+    const common::Length &falseEasting, const common::Length &falseNorthing) {
+    return create(properties, EPSG_CODE_METHOD_MERCATOR_VARIANT_B,
+                  createParams(latitudeFirstParallel, centerLong, falseEasting,
+                               falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Popular Visualisation Pseudo
+ *Mercator]
+ *(https://proj4.org/operations/projections/webmerc.html) projection method.
+ *
+ * Also known as WebMercator. Mostly/only used for Projected CRS EPSG:3857
+ * (WGS 84 / Pseudo-Mercator)
+ *
+ * This method is defined as [EPSG:1024]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::1024)
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLat See \ref center_latitude . Usually 0
+ * @param centerLong See \ref center_longitude . Usually 0
+ * @param falseEasting See \ref false_easting . Usually 0
+ * @param falseNorthing See \ref false_northing . Usually 0
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createPopularVisualisationPseudoMercator(
+    const util::PropertyMap &properties, const common::Angle &centerLat,
+    const common::Angle &centerLong, const common::Length &falseEasting,
+    const common::Length &falseNorthing) {
+    return create(
+        properties, EPSG_CODE_METHOD_POPULAR_VISUALISATION_PSEUDO_MERCATOR,
+        createParams(centerLat, centerLong, falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Mollweide]
+ * (https://proj4.org/operations/projections/moll.html) projection method.
+ *
+ * There is no equivalent in EPSG.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLong See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createMollweide(
+    const util::PropertyMap &properties, const common::Angle &centerLong,
+    const common::Length &falseEasting, const common::Length &falseNorthing) {
+    return create(properties, PROJ_WKT2_NAME_METHOD_MOLLWEIDE,
+                  createParams(centerLong, falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [New Zealand Map Grid]
+ * (https://proj4.org/operations/projections/nzmg.html) projection method.
+ *
+ * This method is defined as [EPSG:9811]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9811)
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLat See \ref center_latitude
+ * @param centerLong See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createNewZealandMappingGrid(
+    const util::PropertyMap &properties, const common::Angle &centerLat,
+    const common::Angle &centerLong, const common::Length &falseEasting,
+    const common::Length &falseNorthing) {
+    return create(
+        properties, EPSG_CODE_METHOD_NZMG,
+        createParams(centerLat, centerLong, falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Oblique Stereographic
+ *(Alternative)]
+ *(https://proj4.org/operations/projections/sterea.html) projection method.
+ *
+ * This method is defined as [EPSG:9809]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9809)
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLat See \ref center_latitude
+ * @param centerLong See \ref center_longitude
+ * @param scale See \ref scale
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createObliqueStereographic(
+    const util::PropertyMap &properties, const common::Angle &centerLat,
+    const common::Angle &centerLong, const common::Scale &scale,
+    const common::Length &falseEasting, const common::Length &falseNorthing) {
+    return create(properties, EPSG_CODE_METHOD_OBLIQUE_STEREOGRAPHIC,
+                  createParams(centerLat, centerLong, scale, falseEasting,
+                               falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Orthographic]
+ *(https://proj4.org/operations/projections/ortho.html) projection method.
+ *
+ * This method is defined as [EPSG:9840]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9840)
+ *
+ * \note At the time of writing, PROJ only implements the spherical formulation
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLat See \ref center_latitude
+ * @param centerLong See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createOrthographic(
+    const util::PropertyMap &properties, const common::Angle &centerLat,
+    const common::Angle &centerLong, const common::Length &falseEasting,
+    const common::Length &falseNorthing) {
+    return create(
+        properties, EPSG_CODE_METHOD_ORTHOGRAPHIC,
+        createParams(centerLat, centerLong, falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [American Polyconic]
+ *(https://proj4.org/operations/projections/poly.html) projection method.
+ *
+ * This method is defined as [EPSG:9818]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9818)
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLat See \ref center_latitude
+ * @param centerLong See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createAmericanPolyconic(
+    const util::PropertyMap &properties, const common::Angle &centerLat,
+    const common::Angle &centerLong, const common::Length &falseEasting,
+    const common::Length &falseNorthing) {
+    return create(
+        properties, EPSG_CODE_METHOD_AMERICAN_POLYCONIC,
+        createParams(centerLat, centerLong, falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Polar Stereographic (Variant
+ *A)]
+ *(https://proj4.org/operations/projections/stere.html) projection method.
+ *
+ * This method is defined as [EPSG:9810]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9810)
+ *
+ * This is the variant of polar stereographic defined with a scale factor.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLat See \ref center_latitude . Should be 90 deg ou -90 deg.
+ * @param centerLong See \ref center_longitude
+ * @param scale See \ref scale
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createPolarStereographicVariantA(
+    const util::PropertyMap &properties, const common::Angle &centerLat,
+    const common::Angle &centerLong, const common::Scale &scale,
+    const common::Length &falseEasting, const common::Length &falseNorthing) {
+    return create(properties, EPSG_CODE_METHOD_POLAR_STEREOGRAPHIC_VARIANT_A,
+                  createParams(centerLat, centerLong, scale, falseEasting,
+                               falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Polar Stereographic (Variant
+ *B)]
+ *(https://proj4.org/operations/projections/stere.html) projection method.
+ *
+ * This method is defined as [EPSG:9829]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9829)
+ *
+ * This is the variant of polar stereographic defined with a latitude of
+ * standard parallel.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param latitudeStandardParallel See \ref latitude_std_parallel
+ * @param longitudeOfOrigin See \ref longitude_of_origin
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createPolarStereographicVariantB(
+    const util::PropertyMap &properties,
+    const common::Angle &latitudeStandardParallel,
+    const common::Angle &longitudeOfOrigin, const common::Length &falseEasting,
+    const common::Length &falseNorthing) {
+    return create(properties, EPSG_CODE_METHOD_POLAR_STEREOGRAPHIC_VARIANT_B,
+                  createParams(latitudeStandardParallel, longitudeOfOrigin,
+                               falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Robinson]
+ * (https://proj4.org/operations/projections/robin.html) projection method.
+ *
+ * There is no equivalent in EPSG.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLong See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createRobinson(
+    const util::PropertyMap &properties, const common::Angle &centerLong,
+    const common::Length &falseEasting, const common::Length &falseNorthing) {
+    return create(properties, PROJ_WKT2_NAME_METHOD_ROBINSON,
+                  createParams(centerLong, falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Sinusoidal]
+ * (https://proj4.org/operations/projections/sinu.html) projection method.
+ *
+ * There is no equivalent in EPSG.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLong See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createSinusoidal(
+    const util::PropertyMap &properties, const common::Angle &centerLong,
+    const common::Length &falseEasting, const common::Length &falseNorthing) {
+    return create(properties, PROJ_WKT2_NAME_METHOD_SINUSOIDAL,
+                  createParams(centerLong, falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Stereographic]
+ *(https://proj4.org/operations/projections/stere.html) projection method.
+ *
+ * There is no equivalent in EPSG. This method implements the original "Oblique
+ * Stereographic" method described in "Snyder's Map Projections - A Working
+ *manual",
+ * which is different from the "Oblique Stereographic (alternative") method
+ * implemented in createObliqueStereographic().
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLat See \ref center_latitude
+ * @param centerLong See \ref center_longitude
+ * @param scale See \ref scale
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createStereographic(
+    const util::PropertyMap &properties, const common::Angle &centerLat,
+    const common::Angle &centerLong, const common::Scale &scale,
+    const common::Length &falseEasting, const common::Length &falseNorthing) {
+    return create(properties, PROJ_WKT2_NAME_METHOD_STEREOGRAPHIC,
+                  createParams(centerLat, centerLong, scale, falseEasting,
+                               falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Van der Grinten]
+ * (https://proj4.org/operations/projections/vandg.html) projection method.
+ *
+ * There is no equivalent in EPSG.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLong See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createVanDerGrinten(
+    const util::PropertyMap &properties, const common::Angle &centerLong,
+    const common::Length &falseEasting, const common::Length &falseNorthing) {
+    return create(properties, PROJ_WKT2_NAME_METHOD_VAN_DER_GRINTEN,
+                  createParams(centerLong, falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Wagner I]
+ * (https://proj4.org/operations/projections/wag1.html) projection method.
+ *
+ * There is no equivalent in EPSG.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLong See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createWagnerI(const util::PropertyMap &properties,
+                                          const common::Angle &centerLong,
+                                          const common::Length &falseEasting,
+                                          const common::Length &falseNorthing) {
+    return create(properties, PROJ_WKT2_NAME_METHOD_WAGNER_I,
+                  createParams(centerLong, falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Wagner II]
+ * (https://proj4.org/operations/projections/wag2.html) projection method.
+ *
+ * There is no equivalent in EPSG.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLong See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createWagnerII(
+    const util::PropertyMap &properties, const common::Angle &centerLong,
+    const common::Length &falseEasting, const common::Length &falseNorthing) {
+    return create(properties, PROJ_WKT2_NAME_METHOD_WAGNER_II,
+                  createParams(centerLong, falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Wagner III]
+ * (https://proj4.org/operations/projections/wag3.html) projection method.
+ *
+ * There is no equivalent in EPSG.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param latitudeTrueScale Latitude of true scale.
+ * @param centerLong See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createWagnerIII(
+    const util::PropertyMap &properties, const common::Angle &latitudeTrueScale,
+    const common::Angle &centerLong, const common::Length &falseEasting,
+    const common::Length &falseNorthing) {
+    return create(properties, PROJ_WKT2_NAME_METHOD_WAGNER_III,
+                  createParams(latitudeTrueScale, centerLong, falseEasting,
+                               falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Wagner IV]
+ * (https://proj4.org/operations/projections/wag4.html) projection method.
+ *
+ * There is no equivalent in EPSG.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLong See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createWagnerIV(
+    const util::PropertyMap &properties, const common::Angle &centerLong,
+    const common::Length &falseEasting, const common::Length &falseNorthing) {
+    return create(properties, PROJ_WKT2_NAME_METHOD_WAGNER_IV,
+                  createParams(centerLong, falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Wagner V]
+ * (https://proj4.org/operations/projections/wag5.html) projection method.
+ *
+ * There is no equivalent in EPSG.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLong See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createWagnerV(const util::PropertyMap &properties,
+                                          const common::Angle &centerLong,
+                                          const common::Length &falseEasting,
+                                          const common::Length &falseNorthing) {
+    return create(properties, PROJ_WKT2_NAME_METHOD_WAGNER_V,
+                  createParams(centerLong, falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Wagner VI]
+ * (https://proj4.org/operations/projections/wag6.html) projection method.
+ *
+ * There is no equivalent in EPSG.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLong See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createWagnerVI(
+    const util::PropertyMap &properties, const common::Angle &centerLong,
+    const common::Length &falseEasting, const common::Length &falseNorthing) {
+    return create(properties, PROJ_WKT2_NAME_METHOD_WAGNER_VI,
+                  createParams(centerLong, falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Wagner VII]
+ * (https://proj4.org/operations/projections/wag7.html) projection method.
+ *
+ * There is no equivalent in EPSG.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLong See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createWagnerVII(
+    const util::PropertyMap &properties, const common::Angle &centerLong,
+    const common::Length &falseEasting, const common::Length &falseNorthing) {
+    return create(properties, PROJ_WKT2_NAME_METHOD_WAGNER_VII,
+                  createParams(centerLong, falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Quadrilateralized Spherical
+ *Cube]
+ *(https://proj4.org/operations/projections/qsc.html) projection method.
+ *
+ * There is no equivalent in EPSG.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLat See \ref center_latitude
+ * @param centerLong See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createQuadrilateralizedSphericalCube(
+    const util::PropertyMap &properties, const common::Angle &centerLat,
+    const common::Angle &centerLong, const common::Length &falseEasting,
+    const common::Length &falseNorthing) {
+    return create(
+        properties, PROJ_WKT2_NAME_METHOD_QUADRILATERALIZED_SPHERICAL_CUBE,
+        createParams(centerLat, centerLong, falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Spherical Cross-Track Height]
+ *(https://proj4.org/operations/projections/sch.html) projection method.
+ *
+ * There is no equivalent in EPSG.
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param pegPointLat Peg point latitude.
+ * @param pegPointLong Peg point longitude.
+ * @param pegPointHeading Peg point heading.
+ * @param pegPointHeight Peg point height.
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createSphericalCrossTrackHeight(
+    const util::PropertyMap &properties, const common::Angle &pegPointLat,
+    const common::Angle &pegPointLong, const common::Angle &pegPointHeading,
+    const common::Length &pegPointHeight) {
+    return create(properties,
+                  PROJ_WKT2_NAME_METHOD_SPHERICAL_CROSS_TRACK_HEIGHT,
+                  createParams(pegPointLat, pegPointLong, pegPointHeading,
+                               pegPointHeight));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the [Equal Earth]
+ * (https://proj4.org/operations/projections/eqearth.html) projection method.
+ *
+ * This method is defined as [EPSG:1078]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::1078)
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param centerLong See \ref center_longitude
+ * @param falseEasting See \ref false_easting
+ * @param falseNorthing See \ref false_northing
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createEqualEarth(
+    const util::PropertyMap &properties, const common::Angle &centerLong,
+    const common::Length &falseEasting, const common::Length &falseNorthing) {
+    return create(properties, EPSG_CODE_METHOD_EQUAL_EARTH,
+                  createParams(centerLong, falseEasting, falseNorthing));
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+static OperationParameterNNPtr createOpParamNameEPSGCode(int code) {
+    const char *name = OperationParameter::getNameForEPSGCode(code);
+    assert(name);
+    return OperationParameter::create(createMapNameEPSGCode(name, code));
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the Change of Vertical Unit
+ * method.
+ *
+ * This method is defined as [EPSG:1069]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::1069)
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @param factor Conversion factor
+ * @return a new Conversion.
+ */
+ConversionNNPtr
+Conversion::createChangeVerticalUnit(const util::PropertyMap &properties,
+                                     const common::Scale &factor) {
+    return create(properties, createMethodMapNameEPSGCode(
+                                  EPSG_CODE_METHOD_CHANGE_VERTICAL_UNIT),
+                  VectorOfParameters{
+                      createOpParamNameEPSGCode(
+                          EPSG_CODE_PARAMETER_UNIT_CONVERSION_SCALAR),
+                  },
+                  VectorOfValues{
+                      factor,
+                  });
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the Axis order reversal method
+ *
+ * This swaps the longitude, latitude axis.
+ *
+ * This method is defined as [EPSG:9843]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9843),
+ * or for 3D as [EPSG:9844]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9844)
+ *
+ * @param is3D Whether this should apply on 3D geographicCRS
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::createAxisOrderReversal(bool is3D) {
+    if (is3D) {
+        return create(createMapNameEPSGCode(
+                          "axis order change (geographic3D horizontal)", 15499),
+                      createMethodMapNameEPSGCode(
+                          EPSG_CODE_METHOD_AXIS_ORDER_REVERSAL_3D),
+                      {}, {});
+    } else {
+        return create(createMapNameEPSGCode("axis order change (2D)", 15498),
+                      createMethodMapNameEPSGCode(
+                          EPSG_CODE_METHOD_AXIS_ORDER_REVERSAL_2D),
+                      {}, {});
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a conversion based on the Geographic/Geocentric method.
+ *
+ * This method is defined as [EPSG:9602]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9602),
+ *
+ * @param properties See \ref general_properties of the conversion. If the name
+ * is not provided, it is automatically set.
+ * @return a new Conversion.
+ */
+ConversionNNPtr
+Conversion::createGeographicGeocentric(const util::PropertyMap &properties) {
+    return create(properties, createMethodMapNameEPSGCode(
+                                  EPSG_CODE_METHOD_GEOGRAPHIC_GEOCENTRIC),
+                  {}, {});
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+static util::PropertyMap &addDomains(util::PropertyMap &map,
+                                     const common::ObjectUsage *obj) {
+
+    auto ar = util::ArrayOfBaseObject::create();
+    for (const auto &domain : obj->domains()) {
+        ar->add(domain);
+    }
+    if (!ar->empty()) {
+        map.set(common::ObjectUsage::OBJECT_DOMAIN_KEY, ar);
+    }
+    return map;
+}
+
+// ---------------------------------------------------------------------------
+
+static void addModifiedIdentifier(util::PropertyMap &map,
+                                  const common::IdentifiedObject *obj,
+                                  bool inverse, bool derivedFrom) {
+    // If original operation is AUTH:CODE, then assign INVERSE(AUTH):CODE
+    // as identifier.
+
+    auto ar = util::ArrayOfBaseObject::create();
+    for (const auto &idSrc : obj->identifiers()) {
+        auto authName = *(idSrc->codeSpace());
+        const auto &srcCode = idSrc->code();
+        if (derivedFrom) {
+            authName = concat("DERIVED_FROM(", authName, ")");
+        }
+        if (inverse) {
+            if (starts_with(authName, "INVERSE(") && authName.back() == ')') {
+                authName = authName.substr(strlen("INVERSE("));
+                authName.resize(authName.size() - 1);
+            } else {
+                authName = concat("INVERSE(", authName, ")");
+            }
+        }
+        auto idsProp = util::PropertyMap().set(
+            metadata::Identifier::CODESPACE_KEY, authName);
+        ar->add(metadata::Identifier::create(srcCode, idsProp));
+    }
+    if (!ar->empty()) {
+        map.set(common::IdentifiedObject::IDENTIFIERS_KEY, ar);
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+static util::PropertyMap
+createPropertiesForInverse(const OperationMethodNNPtr &method) {
+    util::PropertyMap map;
+
+    const std::string &forwardName = method->nameStr();
+    if (!forwardName.empty()) {
+        if (starts_with(forwardName, INVERSE_OF)) {
+            map.set(common::IdentifiedObject::NAME_KEY,
+                    forwardName.substr(INVERSE_OF.size()));
+        } else {
+            map.set(common::IdentifiedObject::NAME_KEY,
+                    INVERSE_OF + forwardName);
+        }
+    }
+
+    addModifiedIdentifier(map, method.get(), true, false);
+
+    return map;
+}
+
+// ---------------------------------------------------------------------------
+
+InverseConversion::InverseConversion(const ConversionNNPtr &forward)
+    : Conversion(
+          OperationMethod::create(createPropertiesForInverse(forward->method()),
+                                  forward->method()->parameters()),
+          forward->parameterValues()),
+      InverseCoordinateOperation(forward, true) {
+    setPropertiesFromForward();
+}
+
+// ---------------------------------------------------------------------------
+
+InverseConversion::~InverseConversion() = default;
+
+// ---------------------------------------------------------------------------
+
+ConversionNNPtr InverseConversion::inverseAsConversion() const {
+    return NN_NO_CHECK(
+        util::nn_dynamic_pointer_cast<Conversion>(forwardOperation_));
+}
+
+// ---------------------------------------------------------------------------
+
+CoordinateOperationNNPtr
+InverseConversion::create(const ConversionNNPtr &forward) {
+    auto conv = util::nn_make_shared<InverseConversion>(forward);
+    conv->assignSelf(conv);
+    return conv;
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+static bool isAxisOrderReversal2D(int methodEPSGCode) {
+    return methodEPSGCode == EPSG_CODE_METHOD_AXIS_ORDER_REVERSAL_2D;
+}
+
+static bool isAxisOrderReversal3D(int methodEPSGCode) {
+    return methodEPSGCode == EPSG_CODE_METHOD_AXIS_ORDER_REVERSAL_3D;
+}
+
+bool isAxisOrderReversal(int methodEPSGCode) {
+    return isAxisOrderReversal2D(methodEPSGCode) ||
+           isAxisOrderReversal3D(methodEPSGCode);
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+CoordinateOperationNNPtr Conversion::inverse() const {
+    const int methodEPSGCode = method()->getEPSGCode();
+
+    if (methodEPSGCode == EPSG_CODE_METHOD_CHANGE_VERTICAL_UNIT) {
+        const double convFactor = parameterValueNumericAsSI(
+            EPSG_CODE_PARAMETER_UNIT_CONVERSION_SCALAR);
+        auto conv = createChangeVerticalUnit(
+            createPropertiesForInverse(this, false, false),
+            common::Scale(1.0 / convFactor));
+        conv->setCRSs(this, true);
+        return conv;
+    }
+
+    const bool l_isAxisOrderReversal2D = isAxisOrderReversal2D(methodEPSGCode);
+    const bool l_isAxisOrderReversal3D = isAxisOrderReversal3D(methodEPSGCode);
+    if (l_isAxisOrderReversal2D || l_isAxisOrderReversal3D) {
+        auto conv = createAxisOrderReversal(l_isAxisOrderReversal3D);
+        conv->setCRSs(this, true);
+        return conv;
+    }
+
+    if (methodEPSGCode == EPSG_CODE_METHOD_GEOGRAPHIC_GEOCENTRIC) {
+
+        auto conv = createGeographicGeocentric(
+            createPropertiesForInverse(this, false, false));
+        conv->setCRSs(this, true);
+        return conv;
+    }
+
+    return InverseConversion::create(NN_NO_CHECK(
+        util::nn_dynamic_pointer_cast<Conversion>(shared_from_this())));
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+static double msfn(double phi, double e2) {
+    const double sinphi = std::sin(phi);
+    const double cosphi = std::cos(phi);
+    return pj_msfn(sinphi, cosphi, e2);
+}
+
+// ---------------------------------------------------------------------------
+
+static double tsfn(double phi, double ec) {
+    const double sinphi = std::sin(phi);
+    return pj_tsfn(phi, sinphi, ec);
+}
+
+// ---------------------------------------------------------------------------
+
+// Function whose zeroes are the sin of the standard parallels of LCC_2SP
+static double lcc_1sp_to_2sp_f(double sinphi, double K, double ec, double n) {
+    const double x = sinphi;
+    const double ecx = ec * x;
+    return (1 - x * x) / (1 - ecx * ecx) -
+           K * K * std::pow((1.0 - x) / (1.0 + x) *
+                                std::pow((1.0 + ecx) / (1.0 - ecx), ec),
+                            n);
+}
+
+// ---------------------------------------------------------------------------
+
+// Find the sin of the standard parallels of LCC_2SP
+static double find_zero_lcc_1sp_to_2sp_f(double sinphi0, bool bNorth, double K,
+                                         double ec) {
+    double a, b;
+    double f_a;
+    if (bNorth) {
+        // Look for zero above phi0
+        a = sinphi0;
+        b = 1.0;   // sin(North pole)
+        f_a = 1.0; // some positive value, but we only care about the sign
+    } else {
+        // Look for zero below phi0
+        a = -1.0; // sin(South pole)
+        b = sinphi0;
+        f_a = -1.0; // minus infinity in fact, but we only care about the sign
+    }
+    // We use dichotomy search. lcc_1sp_to_2sp_f() is positive at sinphi_init,
+    // has a zero in ]-1,sinphi0[ and ]sinphi0,1[ ranges
+    for (int N = 0; N < 100; N++) {
+        double c = (a + b) / 2;
+        double f_c = lcc_1sp_to_2sp_f(c, K, ec, sinphi0);
+        if (f_c == 0.0 || (b - a) < 1e-18) {
+            return c;
+        }
+        if ((f_c > 0 && f_a > 0) || (f_c < 0 && f_a < 0)) {
+            a = c;
+            f_a = f_c;
+        } else {
+            b = c;
+        }
+    }
+    return (a + b) / 2;
+}
+
+static inline double DegToRad(double x) { return x / 180.0 * M_PI; }
+static inline double RadToDeg(double x) { return x / M_PI * 180.0; }
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/**
+ * \brief Return an equivalent projection.
+ *
+ * Currently implemented:
+ * <ul>
+ * <li>EPSG_CODE_METHOD_MERCATOR_VARIANT_A (1SP) to
+ * EPSG_CODE_METHOD_MERCATOR_VARIANT_B (2SP)</li>
+ * <li>EPSG_CODE_METHOD_MERCATOR_VARIANT_B (2SP) to
+ * EPSG_CODE_METHOD_MERCATOR_VARIANT_A (1SP)</li>
+ * <li>EPSG_CODE_METHOD_LAMBERT_CONIC_CONFORMAL_1SP to
+ * EPSG_CODE_METHOD_LAMBERT_CONIC_CONFORMAL_2SP</li>
+ * <li>EPSG_CODE_METHOD_LAMBERT_CONIC_CONFORMAL_2SP to
+ * EPSG_CODE_METHOD_LAMBERT_CONIC_CONFORMAL_1SP</li>
+ * </ul>
+ *
+ * @param targetEPSGCode EPSG code of the target method.
+ * @return new conversion, or nullptr
+ */
+ConversionPtr Conversion::convertToOtherMethod(int targetEPSGCode) const {
+    const int current_epsg_code = method()->getEPSGCode();
+    if (current_epsg_code == targetEPSGCode) {
+        return util::nn_dynamic_pointer_cast<Conversion>(shared_from_this());
+    }
+
+    auto geogCRS = dynamic_cast<crs::GeodeticCRS *>(sourceCRS().get());
+    if (!geogCRS) {
+        return nullptr;
+    }
+
+    const double e2 = geogCRS->ellipsoid()->squaredEccentricity();
+    if (e2 < 0) {
+        return nullptr;
+    }
+
+    if (current_epsg_code == EPSG_CODE_METHOD_MERCATOR_VARIANT_A &&
+        targetEPSGCode == EPSG_CODE_METHOD_MERCATOR_VARIANT_B &&
+        parameterValueNumericAsSI(
+            EPSG_CODE_PARAMETER_LATITUDE_OF_NATURAL_ORIGIN) == 0.0) {
+        const double k0 = parameterValueNumericAsSI(
+            EPSG_CODE_PARAMETER_SCALE_FACTOR_AT_NATURAL_ORIGIN);
+        if (!(k0 > 0 && k0 <= 1.0 + 1e-10))
+            return nullptr;
+        const double dfStdP1Lat =
+            (k0 >= 1.0)
+                ? 0.0
+                : std::acos(std::sqrt((1.0 - e2) / ((1.0 / (k0 * k0)) - e2)));
+        auto latitudeFirstParallel = common::Angle(
+            common::Angle(dfStdP1Lat, common::UnitOfMeasure::RADIAN)
+                .convertToUnit(common::UnitOfMeasure::DEGREE),
+            common::UnitOfMeasure::DEGREE);
+        auto conv = createMercatorVariantB(
+            util::PropertyMap(), latitudeFirstParallel,
+            common::Angle(parameterValueMeasure(
+                EPSG_CODE_PARAMETER_LONGITUDE_OF_NATURAL_ORIGIN)),
+            common::Length(
+                parameterValueMeasure(EPSG_CODE_PARAMETER_FALSE_EASTING)),
+            common::Length(
+                parameterValueMeasure(EPSG_CODE_PARAMETER_FALSE_NORTHING)));
+        conv->setCRSs(this, false);
+        return std::move(conv);
+    }
+
+    if (current_epsg_code == EPSG_CODE_METHOD_MERCATOR_VARIANT_B &&
+        targetEPSGCode == EPSG_CODE_METHOD_MERCATOR_VARIANT_A) {
+        const double phi1 = parameterValueNumericAsSI(
+            EPSG_CODE_PARAMETER_LATITUDE_1ST_STD_PARALLEL);
+        if (!(std::fabs(phi1) < M_PI / 2))
+            return nullptr;
+        const double k0 = msfn(phi1, e2);
+        auto conv = createMercatorVariantA(
+            util::PropertyMap(),
+            common::Angle(0.0, common::UnitOfMeasure::DEGREE),
+            common::Angle(parameterValueMeasure(
+                EPSG_CODE_PARAMETER_LONGITUDE_OF_NATURAL_ORIGIN)),
+            common::Scale(k0, common::UnitOfMeasure::SCALE_UNITY),
+            common::Length(
+                parameterValueMeasure(EPSG_CODE_PARAMETER_FALSE_EASTING)),
+            common::Length(
+                parameterValueMeasure(EPSG_CODE_PARAMETER_FALSE_NORTHING)));
+        conv->setCRSs(this, false);
+        return std::move(conv);
+    }
+
+    if (current_epsg_code == EPSG_CODE_METHOD_LAMBERT_CONIC_CONFORMAL_1SP &&
+        targetEPSGCode == EPSG_CODE_METHOD_LAMBERT_CONIC_CONFORMAL_2SP) {
+        // Notations m0, t0, n, m1, t1, F are those of the EPSG guidance
+        // "1.3.1.1 Lambert Conic Conformal (2SP)" and
+        // "1.3.1.2 Lambert Conic Conformal (1SP)" and
+        // or Snyder pages 106-109
+        auto latitudeOfOrigin = common::Angle(parameterValueMeasure(
+            EPSG_CODE_PARAMETER_LATITUDE_OF_NATURAL_ORIGIN));
+        const double phi0 = latitudeOfOrigin.getSIValue();
+        const double k0 = parameterValueNumericAsSI(
+            EPSG_CODE_PARAMETER_SCALE_FACTOR_AT_NATURAL_ORIGIN);
+        if (!(std::fabs(phi0) < M_PI / 2))
+            return nullptr;
+        if (!(k0 > 0 && k0 <= 1.0 + 1e-10))
+            return nullptr;
+        const double ec = std::sqrt(e2);
+        const double m0 = msfn(phi0, e2);
+        const double t0 = tsfn(phi0, ec);
+        const double n = sin(phi0);
+        if (std::fabs(n) < 1e-10)
+            return nullptr;
+        if (fabs(k0 - 1.0) <= 1e-10) {
+            auto conv = createLambertConicConformal_2SP(
+                util::PropertyMap(), latitudeOfOrigin,
+                common::Angle(parameterValueMeasure(
+                    EPSG_CODE_PARAMETER_LONGITUDE_OF_NATURAL_ORIGIN)),
+                latitudeOfOrigin, latitudeOfOrigin,
+                common::Length(
+                    parameterValueMeasure(EPSG_CODE_PARAMETER_FALSE_EASTING)),
+                common::Length(
+                    parameterValueMeasure(EPSG_CODE_PARAMETER_FALSE_NORTHING)));
+            conv->setCRSs(this, false);
+            return std::move(conv);
+        } else {
+            const double K = k0 * m0 / std::pow(t0, n);
+            const double phi1 =
+                std::asin(find_zero_lcc_1sp_to_2sp_f(n, true, K, ec));
+            const double phi2 =
+                std::asin(find_zero_lcc_1sp_to_2sp_f(n, false, K, ec));
+            double phi1Deg = RadToDeg(phi1);
+            double phi2Deg = RadToDeg(phi2);
+
+            // Try to round to hundreth of degree if very close to it
+            if (std::fabs(phi1Deg * 1000 - std::floor(phi1Deg * 1000 + 0.5)) <
+                1e-8)
+                phi1Deg = floor(phi1Deg * 1000 + 0.5) / 1000;
+            if (std::fabs(phi2Deg * 1000 - std::floor(phi2Deg * 1000 + 0.5)) <
+                1e-8)
+                phi2Deg = std::floor(phi2Deg * 1000 + 0.5) / 1000;
+
+            // The following improvement is too turn the LCC1SP equivalent of
+            // EPSG:2154 to the real LCC2SP
+            // If the computed latitude of origin is close to .0 or .5 degrees
+            // then check if rounding it to it will get a false northing
+            // close to an integer
+            const double FN =
+                parameterValueNumericAsSI(EPSG_CODE_PARAMETER_FALSE_NORTHING);
+            const double latitudeOfOriginDeg =
+                latitudeOfOrigin.convertToUnit(common::UnitOfMeasure::DEGREE);
+            if (std::fabs(latitudeOfOriginDeg * 2 -
+                          std::floor(latitudeOfOriginDeg * 2 + 0.5)) < 0.2) {
+                const double dfRoundedLatOfOrig =
+                    std::floor(latitudeOfOriginDeg * 2 + 0.5) / 2;
+                const double m1 = msfn(phi1, e2);
+                const double t1 = tsfn(phi1, ec);
+                const double F = m1 / (n * std::pow(t1, n));
+                const double a =
+                    geogCRS->ellipsoid()->semiMajorAxis().getSIValue();
+                const double tRoundedLatOfOrig =
+                    tsfn(DegToRad(dfRoundedLatOfOrig), ec);
+                const double FN_correction =
+                    a * F * (std::pow(tRoundedLatOfOrig, n) - std::pow(t0, n));
+                const double FN_corrected = FN - FN_correction;
+                const double FN_corrected_rounded =
+                    std::floor(FN_corrected + 0.5);
+                if (std::fabs(FN_corrected - FN_corrected_rounded) < 1e-8) {
+                    auto conv = createLambertConicConformal_2SP(
+                        util::PropertyMap(),
+                        common::Angle(dfRoundedLatOfOrig,
+                                      common::UnitOfMeasure::DEGREE),
+                        common::Angle(parameterValueMeasure(
+                            EPSG_CODE_PARAMETER_LONGITUDE_OF_NATURAL_ORIGIN)),
+                        common::Angle(phi1Deg, common::UnitOfMeasure::DEGREE),
+                        common::Angle(phi2Deg, common::UnitOfMeasure::DEGREE),
+                        common::Length(parameterValueMeasure(
+                            EPSG_CODE_PARAMETER_FALSE_EASTING)),
+                        common::Length(FN_corrected_rounded));
+                    conv->setCRSs(this, false);
+                    return std::move(conv);
+                }
+            }
+
+            auto conv = createLambertConicConformal_2SP(
+                util::PropertyMap(), latitudeOfOrigin,
+                common::Angle(parameterValueMeasure(
+                    EPSG_CODE_PARAMETER_LONGITUDE_OF_NATURAL_ORIGIN)),
+                common::Angle(phi1Deg, common::UnitOfMeasure::DEGREE),
+                common::Angle(phi2Deg, common::UnitOfMeasure::DEGREE),
+                common::Length(
+                    parameterValueMeasure(EPSG_CODE_PARAMETER_FALSE_EASTING)),
+                common::Length(FN));
+            conv->setCRSs(this, false);
+            return std::move(conv);
+        }
+    }
+
+    if (current_epsg_code == EPSG_CODE_METHOD_LAMBERT_CONIC_CONFORMAL_2SP &&
+        targetEPSGCode == EPSG_CODE_METHOD_LAMBERT_CONIC_CONFORMAL_1SP) {
+        // Notations m0, t0, m1, t1, m2, t2 n, F are those of the EPSG guidance
+        // "1.3.1.1 Lambert Conic Conformal (2SP)" and
+        // "1.3.1.2 Lambert Conic Conformal (1SP)" and
+        // or Snyder pages 106-109
+        const double phiF =
+            parameterValueMeasure(EPSG_CODE_PARAMETER_LATITUDE_FALSE_ORIGIN)
+                .getSIValue();
+        const double phi1 =
+            parameterValueMeasure(EPSG_CODE_PARAMETER_LATITUDE_1ST_STD_PARALLEL)
+                .getSIValue();
+        const double phi2 =
+            parameterValueMeasure(EPSG_CODE_PARAMETER_LATITUDE_2ND_STD_PARALLEL)
+                .getSIValue();
+        if (!(std::fabs(phiF) < M_PI / 2))
+            return nullptr;
+        if (!(std::fabs(phi1) < M_PI / 2))
+            return nullptr;
+        if (!(std::fabs(phi2) < M_PI / 2))
+            return nullptr;
+        const double ec = std::sqrt(e2);
+        const double m1 = msfn(phi1, e2);
+        const double m2 = msfn(phi2, e2);
+        const double t1 = tsfn(phi1, ec);
+        const double t2 = tsfn(phi2, ec);
+        const double n_denom = std::log(t1) - std::log(t2);
+        const double n = (std::fabs(n_denom) < 1e-10)
+                             ? std::sin(phi1)
+                             : (std::log(m1) - std::log(m2)) / n_denom;
+        if (std::fabs(n) < 1e-10)
+            return nullptr;
+        const double F = m1 / (n * std::pow(t1, n));
+        const double phi0 = std::asin(n);
+        const double m0 = msfn(phi0, e2);
+        const double t0 = tsfn(phi0, ec);
+        const double F0 = m0 / (n * std::pow(t0, n));
+        const double k0 = F / F0;
+        const double a = geogCRS->ellipsoid()->semiMajorAxis().getSIValue();
+        const double tF = tsfn(phiF, ec);
+        const double FN_correction =
+            a * F * (std::pow(tF, n) - std::pow(t0, n));
+
+        double phi0Deg = RadToDeg(phi0);
+        // Try to round to thousandth of degree if very close to it
+        if (std::fabs(phi0Deg * 1000 - std::floor(phi0Deg * 1000 + 0.5)) < 1e-8)
+            phi0Deg = std::floor(phi0Deg * 1000 + 0.5) / 1000;
+
+        auto conv = createLambertConicConformal_1SP(
+            util::PropertyMap(),
+            common::Angle(phi0Deg, common::UnitOfMeasure::DEGREE),
+            common::Angle(parameterValueMeasure(
+                EPSG_CODE_PARAMETER_LONGITUDE_FALSE_ORIGIN)),
+            common::Scale(k0), common::Length(parameterValueMeasure(
+                                   EPSG_CODE_PARAMETER_EASTING_FALSE_ORIGIN)),
+            common::Length(
+                parameterValueNumericAsSI(
+                    EPSG_CODE_PARAMETER_NORTHING_FALSE_ORIGIN) +
+                (std::fabs(FN_correction) > 1e-8 ? FN_correction : 0)));
+        conv->setCRSs(this, false);
+        return std::move(conv);
+    }
+
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+static void getESRIMethodNameAndParams(const Conversion *conv,
+                                       const std::string &methodName,
+                                       int methodEPSGCode,
+                                       const char *&esriMethodName,
+                                       const ESRIParamMapping *&esriParams) {
+    esriParams = nullptr;
+    esriMethodName = nullptr;
+    const auto *esriMapping = getESRIMapping(methodName, methodEPSGCode);
+    const auto l_targetCRS = conv->targetCRS();
+    if (esriMapping) {
+        esriParams = esriMapping->params;
+        esriMethodName = esriMapping->esri_name;
+        if (esriMapping->epsg_code ==
+                EPSG_CODE_METHOD_EQUIDISTANT_CYLINDRICAL ||
+            esriMapping->epsg_code ==
+                EPSG_CODE_METHOD_EQUIDISTANT_CYLINDRICAL_SPHERICAL) {
+            if (l_targetCRS &&
+                ci_find(l_targetCRS->nameStr(), "Plate Carree") !=
+                    std::string::npos &&
+                conv->parameterValueNumericAsSI(
+                    EPSG_CODE_PARAMETER_LATITUDE_OF_NATURAL_ORIGIN) == 0.0) {
+                esriParams = paramsESRI_Plate_Carree;
+                esriMethodName = "Plate_Carree";
+            } else {
+                esriParams = paramsESRI_Equidistant_Cylindrical;
+                esriMethodName = "Equidistant_Cylindrical";
+            }
+        } else if (esriMapping->epsg_code ==
+                   EPSG_CODE_METHOD_TRANSVERSE_MERCATOR) {
+            if (l_targetCRS &&
+                (ci_find(l_targetCRS->nameStr(), "Gauss") !=
+                     std::string::npos ||
+                 ci_find(l_targetCRS->nameStr(), "GK_") != std::string::npos)) {
+                esriParams = paramsESRI_Gauss_Kruger;
+                esriMethodName = "Gauss_Kruger";
+            } else {
+                esriParams = paramsESRI_Transverse_Mercator;
+                esriMethodName = "Transverse_Mercator";
+            }
+        } else if (esriMapping->epsg_code ==
+                   EPSG_CODE_METHOD_HOTINE_OBLIQUE_MERCATOR_VARIANT_A) {
+            if (std::abs(
+                    conv->parameterValueNumericAsSI(
+                        EPSG_CODE_PARAMETER_AZIMUTH_INITIAL_LINE) -
+                    conv->parameterValueNumericAsSI(
+                        EPSG_CODE_PARAMETER_ANGLE_RECTIFIED_TO_SKEW_GRID)) <
+                1e-15) {
+                esriParams =
+                    paramsESRI_Hotine_Oblique_Mercator_Azimuth_Natural_Origin;
+                esriMethodName =
+                    "Hotine_Oblique_Mercator_Azimuth_Natural_Origin";
+            } else {
+                esriParams =
+                    paramsESRI_Rectified_Skew_Orthomorphic_Natural_Origin;
+                esriMethodName = "Rectified_Skew_Orthomorphic_Natural_Origin";
+            }
+        } else if (esriMapping->epsg_code ==
+                   EPSG_CODE_METHOD_HOTINE_OBLIQUE_MERCATOR_VARIANT_B) {
+            if (std::abs(
+                    conv->parameterValueNumericAsSI(
+                        EPSG_CODE_PARAMETER_AZIMUTH_INITIAL_LINE) -
+                    conv->parameterValueNumericAsSI(
+                        EPSG_CODE_PARAMETER_ANGLE_RECTIFIED_TO_SKEW_GRID)) <
+                1e-15) {
+                esriParams = paramsESRI_Hotine_Oblique_Mercator_Azimuth_Center;
+                esriMethodName = "Hotine_Oblique_Mercator_Azimuth_Center";
+            } else {
+                esriParams = paramsESRI_Rectified_Skew_Orthomorphic_Center;
+                esriMethodName = "Rectified_Skew_Orthomorphic_Center";
+            }
+        } else if (esriMapping->epsg_code ==
+                   EPSG_CODE_METHOD_POLAR_STEREOGRAPHIC_VARIANT_B) {
+            if (conv->parameterValueNumericAsSI(
+                    EPSG_CODE_PARAMETER_LATITUDE_STD_PARALLEL) > 0) {
+                esriMethodName = "Stereographic_North_Pole";
+            } else {
+                esriMethodName = "Stereographic_South_Pole";
+            }
+        }
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+const char *Conversion::getESRIMethodName() const {
+    const auto &l_method = method();
+    const auto &methodName = l_method->nameStr();
+    const auto methodEPSGCode = l_method->getEPSGCode();
+    const ESRIParamMapping *esriParams = nullptr;
+    const char *esriMethodName = nullptr;
+    getESRIMethodNameAndParams(this, methodName, methodEPSGCode, esriMethodName,
+                               esriParams);
+    return esriMethodName;
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+const char *Conversion::getWKT1GDALMethodName() const {
+    const auto &l_method = method();
+    const auto methodEPSGCode = l_method->getEPSGCode();
+    if (methodEPSGCode ==
+        EPSG_CODE_METHOD_POPULAR_VISUALISATION_PSEUDO_MERCATOR) {
+        return "Mercator_1SP";
+    }
+    const MethodMapping *mapping = getMapping(l_method.get());
+    return mapping ? mapping->wkt1_name : nullptr;
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void Conversion::_exportToWKT(io::WKTFormatter *formatter) const {
+    const auto &l_method = method();
+    const auto &methodName = l_method->nameStr();
+    const auto methodEPSGCode = l_method->getEPSGCode();
+    const bool isWKT2 = formatter->version() == io::WKTFormatter::Version::WKT2;
+
+    if (!isWKT2 && formatter->useESRIDialect()) {
+        if (methodEPSGCode == EPSG_CODE_METHOD_MERCATOR_VARIANT_A) {
+            auto eqConv =
+                convertToOtherMethod(EPSG_CODE_METHOD_MERCATOR_VARIANT_B);
+            if (eqConv) {
+                eqConv->_exportToWKT(formatter);
+                return;
+            }
+        }
+    }
+
+    if (isWKT2) {
+        formatter->startNode(formatter->useDerivingConversion()
+                                 ? io::WKTConstants::DERIVINGCONVERSION
+                                 : io::WKTConstants::CONVERSION,
+                             !identifiers().empty());
+        formatter->addQuotedString(nameStr());
+    } else {
+        formatter->enter();
+        formatter->pushOutputUnit(false);
+        formatter->pushOutputId(false);
+    }
+
+    bool bAlreadyWritten = false;
+    if (!isWKT2 && formatter->useESRIDialect()) {
+        const ESRIParamMapping *esriParams = nullptr;
+        const char *esriMethodName = nullptr;
+        getESRIMethodNameAndParams(this, methodName, methodEPSGCode,
+                                   esriMethodName, esriParams);
+        if (esriMethodName && esriParams) {
+            formatter->startNode(io::WKTConstants::PROJECTION, false);
+            formatter->addQuotedString(esriMethodName);
+            formatter->endNode();
+
+            for (int i = 0; esriParams[i].esri_name != nullptr; i++) {
+                const auto &esriParam = esriParams[i];
+                formatter->startNode(io::WKTConstants::PARAMETER, false);
+                formatter->addQuotedString(esriParam.esri_name);
+                if (esriParam.wkt2_name) {
+                    const auto &pv = parameterValue(esriParam.wkt2_name,
+                                                    esriParam.epsg_code);
+                    if (pv && pv->type() == ParameterValue::Type::MEASURE) {
+                        const auto &v = pv->value();
+                        // as we don't output the natural unit, output
+                        // to the registered linear / angular unit.
+                        const auto &unitType = v.unit().type();
+                        if (unitType == common::UnitOfMeasure::Type::LINEAR) {
+                            formatter->add(v.convertToUnit(
+                                *(formatter->axisLinearUnit())));
+                        } else if (unitType ==
+                                   common::UnitOfMeasure::Type::ANGULAR) {
+                            const auto &angUnit =
+                                *(formatter->axisAngularUnit());
+                            double val = v.convertToUnit(angUnit);
+                            if (angUnit == common::UnitOfMeasure::DEGREE) {
+                                if (val > 180.0) {
+                                    val -= 360.0;
+                                } else if (val < -180.0) {
+                                    val += 360.0;
+                                }
+                            }
+                            formatter->add(val);
+                        } else {
+                            formatter->add(v.getSIValue());
+                        }
+                    } else if (ci_find(esriParam.esri_name, "scale") !=
+                               std::string::npos) {
+                        formatter->add(1.0);
+                    } else {
+                        formatter->add(0.0);
+                    }
+                } else {
+                    formatter->add(esriParam.fixed_value);
+                }
+                formatter->endNode();
+            }
+            bAlreadyWritten = true;
+        }
+    } else if (!isWKT2) {
+        if (methodEPSGCode ==
+            EPSG_CODE_METHOD_POPULAR_VISUALISATION_PSEUDO_MERCATOR) {
+            const double latitudeOrigin = parameterValueNumeric(
+                EPSG_CODE_PARAMETER_LATITUDE_OF_NATURAL_ORIGIN,
+                common::UnitOfMeasure::DEGREE);
+            if (latitudeOrigin != 0) {
+                throw io::FormattingException(
+                    std::string("Unsupported value for ") +
+                    EPSG_NAME_PARAMETER_LATITUDE_OF_NATURAL_ORIGIN);
+            }
+
+            bAlreadyWritten = true;
+            formatter->startNode(io::WKTConstants::PROJECTION, false);
+            formatter->addQuotedString("Mercator_1SP");
+            formatter->endNode();
+
+            formatter->startNode(io::WKTConstants::PARAMETER, false);
+            formatter->addQuotedString("central_meridian");
+            const double centralMeridian = parameterValueNumeric(
+                EPSG_CODE_PARAMETER_LONGITUDE_OF_NATURAL_ORIGIN,
+                common::UnitOfMeasure::DEGREE);
+            formatter->add(centralMeridian);
+            formatter->endNode();
+
+            formatter->startNode(io::WKTConstants::PARAMETER, false);
+            formatter->addQuotedString("scale_factor");
+            formatter->add(1.0);
+            formatter->endNode();
+
+            formatter->startNode(io::WKTConstants::PARAMETER, false);
+            formatter->addQuotedString("false_easting");
+            const double falseEasting =
+                parameterValueNumericAsSI(EPSG_CODE_PARAMETER_FALSE_EASTING);
+            formatter->add(falseEasting);
+            formatter->endNode();
+
+            formatter->startNode(io::WKTConstants::PARAMETER, false);
+            formatter->addQuotedString("false_northing");
+            const double falseNorthing =
+                parameterValueNumericAsSI(EPSG_CODE_PARAMETER_FALSE_NORTHING);
+            formatter->add(falseNorthing);
+            formatter->endNode();
+        } else if (starts_with(methodName, "PROJ ")) {
+            bAlreadyWritten = true;
+            formatter->startNode(io::WKTConstants::PROJECTION, false);
+            formatter->addQuotedString("custom_proj4");
+            formatter->endNode();
+        }
+    }
+
+    if (!bAlreadyWritten) {
+        l_method->_exportToWKT(formatter);
+
+        const MethodMapping *mapping =
+            !isWKT2 ? getMapping(l_method.get()) : nullptr;
+        for (const auto &genOpParamvalue : parameterValues()) {
+
+            // EPSG has normally no Latitude of natural origin for Equidistant
+            // Cylindrical but PROJ can handle it, so output the parameter if
+            // not zero
+            if ((methodEPSGCode == EPSG_CODE_METHOD_EQUIDISTANT_CYLINDRICAL ||
+                 methodEPSGCode ==
+                     EPSG_CODE_METHOD_EQUIDISTANT_CYLINDRICAL_SPHERICAL)) {
+                auto opParamvalue =
+                    dynamic_cast<const OperationParameterValue *>(
+                        genOpParamvalue.get());
+                if (opParamvalue &&
+                    opParamvalue->parameter()->getEPSGCode() ==
+                        EPSG_CODE_PARAMETER_LATITUDE_OF_NATURAL_ORIGIN) {
+                    const auto &paramValue = opParamvalue->parameterValue();
+                    if (paramValue->type() == ParameterValue::Type::MEASURE) {
+                        const auto &measure = paramValue->value();
+                        if (measure.getSIValue() == 0) {
+                            continue;
+                        }
+                    }
+                }
+            }
+            genOpParamvalue->_exportToWKT(formatter, mapping);
+        }
+    }
+
+    if (isWKT2) {
+        if (formatter->outputId()) {
+            formatID(formatter);
+        }
+        formatter->endNode();
+    } else {
+        formatter->popOutputUnit();
+        formatter->popOutputId();
+        formatter->leave();
+    }
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static bool createPROJ4WebMercator(const Conversion *conv,
+                                   io::PROJStringFormatter *formatter) {
+    const double centralMeridian = conv->parameterValueNumeric(
+        EPSG_CODE_PARAMETER_LONGITUDE_OF_NATURAL_ORIGIN,
+        common::UnitOfMeasure::DEGREE);
+
+    const double falseEasting =
+        conv->parameterValueNumericAsSI(EPSG_CODE_PARAMETER_FALSE_EASTING);
+
+    const double falseNorthing =
+        conv->parameterValueNumericAsSI(EPSG_CODE_PARAMETER_FALSE_NORTHING);
+
+    auto sourceCRS = conv->sourceCRS();
+    auto geogCRS = dynamic_cast<const crs::GeographicCRS *>(sourceCRS.get());
+    if (!geogCRS) {
+        return false;
+    }
+
+    formatter->addStep("merc");
+    const double a = geogCRS->ellipsoid()->semiMajorAxis().getSIValue();
+    formatter->addParam("a", a);
+    formatter->addParam("b", a);
+    formatter->addParam("lat_ts", 0.0);
+    formatter->addParam("lon_0", centralMeridian);
+    formatter->addParam("x_0", falseEasting);
+    formatter->addParam("y_0", falseNorthing);
+    formatter->addParam("k", 1.0);
+    formatter->addParam("units", "m");
+    formatter->addParam("nadgrids", "@null");
+    formatter->addParam("wktext");
+    formatter->addParam("no_defs");
+    return true;
+}
+
+// ---------------------------------------------------------------------------
+
+static bool
+createPROJExtensionFromCustomProj(const Conversion *conv,
+                                  io::PROJStringFormatter *formatter,
+                                  bool forExtensionNode) {
+    const auto &methodName = conv->method()->nameStr();
+    assert(starts_with(methodName, "PROJ "));
+    auto tokens = split(methodName, ' ');
+
+    formatter->addStep(tokens[1]);
+
+    if (forExtensionNode) {
+        auto sourceCRS = conv->sourceCRS();
+        auto geogCRS =
+            dynamic_cast<const crs::GeographicCRS *>(sourceCRS.get());
+        if (!geogCRS) {
+            return false;
+        }
+        geogCRS->addDatumInfoToPROJString(formatter);
+    }
+
+    for (size_t i = 2; i < tokens.size(); i++) {
+        auto kv = split(tokens[i], '=');
+        if (kv.size() == 2) {
+            formatter->addParam(kv[0], kv[1]);
+        } else {
+            formatter->addParam(tokens[i]);
+        }
+    }
+
+    for (const auto &genOpParamvalue : conv->parameterValues()) {
+        auto opParamvalue = dynamic_cast<const OperationParameterValue *>(
+            genOpParamvalue.get());
+        if (opParamvalue) {
+            const auto &paramName = opParamvalue->parameter()->nameStr();
+            const auto &paramValue = opParamvalue->parameterValue();
+            if (paramValue->type() == ParameterValue::Type::MEASURE) {
+                const auto &measure = paramValue->value();
+                const auto unitType = measure.unit().type();
+                if (unitType == common::UnitOfMeasure::Type::LINEAR) {
+                    formatter->addParam(paramName, measure.getSIValue());
+                } else if (unitType == common::UnitOfMeasure::Type::ANGULAR) {
+                    formatter->addParam(
+                        paramName,
+                        measure.convertToUnit(common::UnitOfMeasure::DEGREE));
+                } else {
+                    formatter->addParam(paramName, measure.value());
+                }
+            }
+        }
+    }
+
+    if (forExtensionNode) {
+        formatter->addParam("wktext");
+        formatter->addParam("no_defs");
+    }
+    return true;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+bool Conversion::addWKTExtensionNode(io::WKTFormatter *formatter) const {
+    const bool isWKT2 = formatter->version() == io::WKTFormatter::Version::WKT2;
+    if (!isWKT2) {
+        const auto &l_method = method();
+        const auto &methodName = l_method->nameStr();
+        const int methodEPSGCode = l_method->getEPSGCode();
+        int zone = 0;
+        bool north = true;
+        if (l_method->getPrivate()->projMethodOverride_ == "etmerc" &&
+            !isUTM(zone, north)) {
+            auto projFormatter = io::PROJStringFormatter::create(
+                io::PROJStringFormatter::Convention::PROJ_4);
+            projFormatter->setUseETMercForTMerc(true);
+            formatter->startNode(io::WKTConstants::EXTENSION, false);
+            formatter->addQuotedString("PROJ4");
+            _exportToPROJString(projFormatter.get());
+            projFormatter->addParam("no_defs");
+            formatter->addQuotedString(projFormatter->toString());
+            formatter->endNode();
+            return true;
+        } else if (methodEPSGCode ==
+                       EPSG_CODE_METHOD_POPULAR_VISUALISATION_PSEUDO_MERCATOR ||
+                   nameStr() == "Popular Visualisation Mercator") {
+
+            auto projFormatter = io::PROJStringFormatter::create(
+                io::PROJStringFormatter::Convention::PROJ_4);
+            if (createPROJ4WebMercator(this, projFormatter.get())) {
+                formatter->startNode(io::WKTConstants::EXTENSION, false);
+                formatter->addQuotedString("PROJ4");
+                formatter->addQuotedString(projFormatter->toString());
+                formatter->endNode();
+                return true;
+            }
+        } else if (starts_with(methodName, "PROJ ")) {
+            auto projFormatter = io::PROJStringFormatter::create(
+                io::PROJStringFormatter::Convention::PROJ_4);
+            if (createPROJExtensionFromCustomProj(this, projFormatter.get(),
+                                                  true)) {
+                formatter->startNode(io::WKTConstants::EXTENSION, false);
+                formatter->addQuotedString("PROJ4");
+                formatter->addQuotedString(projFormatter->toString());
+                formatter->endNode();
+                return true;
+            }
+        } else if (methodName ==
+                   PROJ_WKT2_NAME_METHOD_GEOSTATIONARY_SATELLITE_SWEEP_X) {
+            auto projFormatter = io::PROJStringFormatter::create(
+                io::PROJStringFormatter::Convention::PROJ_4);
+            formatter->startNode(io::WKTConstants::EXTENSION, false);
+            formatter->addQuotedString("PROJ4");
+            _exportToPROJString(projFormatter.get());
+            projFormatter->addParam("no_defs");
+            formatter->addQuotedString(projFormatter->toString());
+            formatter->endNode();
+            return true;
+        }
+    }
+    return false;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void Conversion::_exportToPROJString(
+    io::PROJStringFormatter *formatter) const // throw(FormattingException)
+{
+    const auto &l_method = method();
+    const auto &methodName = l_method->nameStr();
+    const int methodEPSGCode = l_method->getEPSGCode();
+    const bool isZUnitConversion =
+        methodEPSGCode == EPSG_CODE_METHOD_CHANGE_VERTICAL_UNIT;
+    const bool isAffineParametric =
+        methodEPSGCode == EPSG_CODE_METHOD_AFFINE_PARAMETRIC_TRANSFORMATION;
+    const bool isGeographicGeocentric =
+        methodEPSGCode == EPSG_CODE_METHOD_GEOGRAPHIC_GEOCENTRIC;
+    const bool applySourceCRSModifiers =
+        !isZUnitConversion && !isAffineParametric &&
+        !isAxisOrderReversal(methodEPSGCode) && !isGeographicGeocentric;
+    const bool applyTargetCRSModifiers = applySourceCRSModifiers;
+
+    auto l_sourceCRS = sourceCRS();
+    if (l_sourceCRS && applySourceCRSModifiers &&
+        formatter->convention() ==
+            io::PROJStringFormatter::Convention::PROJ_5) {
+        auto geogCRS =
+            dynamic_cast<const crs::GeographicCRS *>(l_sourceCRS.get());
+        if (geogCRS) {
+            formatter->setOmitProjLongLatIfPossible(true);
+            formatter->startInversion();
+            geogCRS->_exportToPROJString(formatter);
+            formatter->stopInversion();
+            formatter->setOmitProjLongLatIfPossible(false);
+        }
+
+        auto projCRS =
+            dynamic_cast<const crs::ProjectedCRS *>(l_sourceCRS.get());
+        if (projCRS) {
+            formatter->startInversion();
+            projCRS->addUnitConvertAndAxisSwap(formatter, false);
+            formatter->stopInversion();
+        }
+    }
+
+    const auto &convName = nameStr();
+    bool bConversionDone = false;
+    bool bEllipsoidParametersDone = false;
+    bool useETMerc = false;
+    if (methodEPSGCode == EPSG_CODE_METHOD_TRANSVERSE_MERCATOR) {
+        // Check for UTM
+        int zone = 0;
+        bool north = true;
+        bool etMercSettingSet = false;
+        useETMerc = formatter->getUseETMercForTMerc(etMercSettingSet) ||
+                    l_method->getPrivate()->projMethodOverride_ == "etmerc";
+        if (isUTM(zone, north) && !(etMercSettingSet && !useETMerc)) {
+            bConversionDone = true;
+            formatter->addStep("utm");
+            formatter->addParam("zone", zone);
+            if (!north) {
+                formatter->addParam("south");
+            }
+        }
+    } else if (methodEPSGCode ==
+               EPSG_CODE_METHOD_HOTINE_OBLIQUE_MERCATOR_VARIANT_A) {
+        const double azimuth =
+            parameterValueNumeric(EPSG_CODE_PARAMETER_AZIMUTH_INITIAL_LINE,
+                                  common::UnitOfMeasure::DEGREE);
+        const double angleRectifiedToSkewGrid = parameterValueNumeric(
+            EPSG_CODE_PARAMETER_ANGLE_RECTIFIED_TO_SKEW_GRID,
+            common::UnitOfMeasure::DEGREE);
+        // Map to Swiss Oblique Mercator / somerc
+        if (std::fabs(azimuth - 90) < 1e-4 &&
+            std::fabs(angleRectifiedToSkewGrid - 90) < 1e-4) {
+            bConversionDone = true;
+            formatter->addStep("somerc");
+            formatter->addParam(
+                "lat_0", parameterValueNumeric(
+                             EPSG_CODE_PARAMETER_LATITUDE_PROJECTION_CENTRE,
+                             common::UnitOfMeasure::DEGREE));
+            formatter->addParam(
+                "lon_0", parameterValueNumeric(
+                             EPSG_CODE_PARAMETER_LONGITUDE_PROJECTION_CENTRE,
+                             common::UnitOfMeasure::DEGREE));
+            formatter->addParam(
+                "k_0", parameterValueNumericAsSI(
+                           EPSG_CODE_PARAMETER_SCALE_FACTOR_INITIAL_LINE));
+            formatter->addParam("x_0", parameterValueNumericAsSI(
+                                           EPSG_CODE_PARAMETER_FALSE_EASTING));
+            formatter->addParam("y_0", parameterValueNumericAsSI(
+                                           EPSG_CODE_PARAMETER_FALSE_NORTHING));
+        }
+    } else if (methodEPSGCode ==
+               EPSG_CODE_METHOD_HOTINE_OBLIQUE_MERCATOR_VARIANT_B) {
+        const double azimuth =
+            parameterValueNumeric(EPSG_CODE_PARAMETER_AZIMUTH_INITIAL_LINE,
+                                  common::UnitOfMeasure::DEGREE);
+        const double angleRectifiedToSkewGrid = parameterValueNumeric(
+            EPSG_CODE_PARAMETER_ANGLE_RECTIFIED_TO_SKEW_GRID,
+            common::UnitOfMeasure::DEGREE);
+        // Map to Swiss Oblique Mercator / somerc
+        if (std::fabs(azimuth - 90) < 1e-4 &&
+            std::fabs(angleRectifiedToSkewGrid - 90) < 1e-4) {
+            bConversionDone = true;
+            formatter->addStep("somerc");
+            formatter->addParam(
+                "lat_0", parameterValueNumeric(
+                             EPSG_CODE_PARAMETER_LATITUDE_PROJECTION_CENTRE,
+                             common::UnitOfMeasure::DEGREE));
+            formatter->addParam(
+                "lon_0", parameterValueNumeric(
+                             EPSG_CODE_PARAMETER_LONGITUDE_PROJECTION_CENTRE,
+                             common::UnitOfMeasure::DEGREE));
+            formatter->addParam(
+                "k_0", parameterValueNumericAsSI(
+                           EPSG_CODE_PARAMETER_SCALE_FACTOR_INITIAL_LINE));
+            formatter->addParam(
+                "x_0", parameterValueNumericAsSI(
+                           EPSG_CODE_PARAMETER_EASTING_PROJECTION_CENTRE));
+            formatter->addParam(
+                "y_0", parameterValueNumericAsSI(
+                           EPSG_CODE_PARAMETER_NORTHING_PROJECTION_CENTRE));
+        }
+    } else if (methodEPSGCode == EPSG_CODE_METHOD_KROVAK_NORTH_ORIENTED) {
+        double colatitude =
+            parameterValueNumeric(EPSG_CODE_PARAMETER_COLATITUDE_CONE_AXIS,
+                                  common::UnitOfMeasure::DEGREE);
+        double latitudePseudoStandardParallel = parameterValueNumeric(
+            EPSG_CODE_PARAMETER_LATITUDE_PSEUDO_STANDARD_PARALLEL,
+            common::UnitOfMeasure::DEGREE);
+        // 30deg 17' 17.30311'' = 30.28813975277777776
+        // 30deg 17' 17.303''   = 30.288139722222223 as used in GDAL WKT1
+        if (std::fabs(colatitude - 30.2881397) > 1e-7) {
+            throw io::FormattingException(
+                std::string("Unsupported value for ") +
+                EPSG_NAME_PARAMETER_COLATITUDE_CONE_AXIS);
+        }
+        if (std::fabs(latitudePseudoStandardParallel - 78.5) > 1e-8) {
+            throw io::FormattingException(
+                std::string("Unsupported value for ") +
+                EPSG_NAME_PARAMETER_LATITUDE_PSEUDO_STANDARD_PARALLEL);
+        }
+    } else if (methodEPSGCode == EPSG_CODE_METHOD_MERCATOR_VARIANT_A) {
+        double latitudeOrigin = parameterValueNumeric(
+            EPSG_CODE_PARAMETER_LATITUDE_OF_NATURAL_ORIGIN,
+            common::UnitOfMeasure::DEGREE);
+        if (latitudeOrigin != 0) {
+            throw io::FormattingException(
+                std::string("Unsupported value for ") +
+                EPSG_NAME_PARAMETER_LATITUDE_OF_NATURAL_ORIGIN);
+        }
+    } else if (methodEPSGCode == EPSG_CODE_METHOD_MERCATOR_VARIANT_B) {
+        const auto &scaleFactor = parameterValueMeasure(WKT1_SCALE_FACTOR, 0);
+        if (scaleFactor.unit().type() != common::UnitOfMeasure::Type::UNKNOWN &&
+            std::fabs(scaleFactor.getSIValue() - 1.0) > 1e-10) {
+            throw io::FormattingException(
+                "Unexpected presence of scale factor in Mercator (variant B)");
+        }
+        double latitudeOrigin = parameterValueNumeric(
+            EPSG_CODE_PARAMETER_LATITUDE_OF_NATURAL_ORIGIN,
+            common::UnitOfMeasure::DEGREE);
+        if (latitudeOrigin != 0) {
+            throw io::FormattingException(
+                std::string("Unsupported value for ") +
+                EPSG_NAME_PARAMETER_LATITUDE_OF_NATURAL_ORIGIN);
+        }
+        // PROJ.4 specific hack for webmercator
+    } else if (formatter->convention() ==
+                   io::PROJStringFormatter::Convention::PROJ_4 &&
+               methodEPSGCode ==
+                   EPSG_CODE_METHOD_POPULAR_VISUALISATION_PSEUDO_MERCATOR) {
+        if (!createPROJ4WebMercator(this, formatter)) {
+            throw io::FormattingException(
+                std::string("Cannot export ") +
+                EPSG_NAME_METHOD_POPULAR_VISUALISATION_PSEUDO_MERCATOR +
+                " as PROJ.4 string outside of a ProjectedCRS context");
+        }
+        bConversionDone = true;
+        bEllipsoidParametersDone = true;
+    } else if (ci_equal(convName, "Popular Visualisation Mercator")) {
+        if (formatter->convention() ==
+            io::PROJStringFormatter::Convention::PROJ_4) {
+            if (!createPROJ4WebMercator(this, formatter)) {
+                throw io::FormattingException(concat(
+                    "Cannot export ", convName,
+                    " as PROJ.4 string outside of a ProjectedCRS context"));
+            }
+        } else {
+            formatter->addStep("webmerc");
+            if (l_sourceCRS) {
+                datum::Ellipsoid::WGS84->_exportToPROJString(formatter);
+            }
+        }
+        bConversionDone = true;
+        bEllipsoidParametersDone = true;
+    } else if (starts_with(methodName, "PROJ ")) {
+        bConversionDone = true;
+        createPROJExtensionFromCustomProj(this, formatter, false);
+    } else if (formatter->convention() ==
+                   io::PROJStringFormatter::Convention::PROJ_5 &&
+               isZUnitConversion) {
+        double convFactor = parameterValueNumericAsSI(
+            EPSG_CODE_PARAMETER_UNIT_CONVERSION_SCALAR);
+        auto uom = common::UnitOfMeasure(std::string(), convFactor,
+                                         common::UnitOfMeasure::Type::LINEAR)
+                       .exportToPROJString();
+        auto reverse_uom =
+            common::UnitOfMeasure(std::string(), 1.0 / convFactor,
+                                  common::UnitOfMeasure::Type::LINEAR)
+                .exportToPROJString();
+        if (!uom.empty()) {
+            formatter->addStep("unitconvert");
+            formatter->addParam("z_in", uom);
+            formatter->addParam("z_out", "m");
+        } else if (!reverse_uom.empty()) {
+            formatter->addStep("unitconvert");
+            formatter->addParam("z_in", "m");
+            formatter->addParam("z_out", reverse_uom);
+        } else {
+            formatter->addStep("affine");
+            formatter->addParam("s33", convFactor);
+        }
+        bConversionDone = true;
+        bEllipsoidParametersDone = true;
+    }
+
+    bool bAxisSpecFound = false;
+    if (!bConversionDone) {
+        const MethodMapping *mapping = getMapping(l_method.get());
+        if (mapping && mapping->proj_name_main) {
+            formatter->addStep(useETMerc ? "etmerc" : mapping->proj_name_main);
+            if (mapping->proj_name_aux) {
+                if (internal::starts_with(mapping->proj_name_aux, "axis=")) {
+                    bAxisSpecFound = true;
+                }
+                auto kv = split(mapping->proj_name_aux, '=');
+                if (kv.size() == 2) {
+                    formatter->addParam(kv[0], kv[1]);
+                } else {
+                    formatter->addParam(mapping->proj_name_aux);
+                }
+            }
+
+            if (mapping->epsg_code ==
+                EPSG_CODE_METHOD_POLAR_STEREOGRAPHIC_VARIANT_B) {
+                double latitudeStdParallel = parameterValueNumeric(
+                    EPSG_CODE_PARAMETER_LATITUDE_STD_PARALLEL,
+                    common::UnitOfMeasure::DEGREE);
+                formatter->addParam("lat_0",
+                                    (latitudeStdParallel >= 0) ? 90.0 : -90.0);
+            }
+
+            for (int i = 0; mapping->params[i] != nullptr; i++) {
+                const auto *param = mapping->params[i];
+                if (!param->proj_name) {
+                    continue;
+                }
+                auto value =
+                    parameterValueMeasure(param->wkt2_name, param->epsg_code);
+                if (mapping->epsg_code ==
+                        EPSG_CODE_METHOD_LAMBERT_CONIC_CONFORMAL_1SP &&
+                    strcmp(param->proj_name, "lat_1") == 0) {
+                    formatter->addParam(
+                        param->proj_name,
+                        value.convertToUnit(common::UnitOfMeasure::DEGREE));
+                    formatter->addParam(
+                        "lat_0",
+                        value.convertToUnit(common::UnitOfMeasure::DEGREE));
+                } else if (param->unit_type ==
+                           common::UnitOfMeasure::Type::ANGULAR) {
+                    formatter->addParam(
+                        param->proj_name,
+                        value.convertToUnit(common::UnitOfMeasure::DEGREE));
+                } else {
+                    formatter->addParam(param->proj_name, value.getSIValue());
+                }
+            }
+
+        } else {
+            if (!exportToPROJStringGeneric(formatter)) {
+                throw io::FormattingException(
+                    concat("Unsupported conversion method: ", methodName));
+            }
+        }
+    }
+
+    auto l_targetCRS = targetCRS();
+    if (l_targetCRS && applyTargetCRSModifiers) {
+        if (!bEllipsoidParametersDone) {
+            auto targetGeogCRS = l_targetCRS->extractGeographicCRS();
+            if (targetGeogCRS) {
+                if (formatter->convention() ==
+                    io::PROJStringFormatter::Convention::PROJ_4) {
+                    targetGeogCRS->addDatumInfoToPROJString(formatter);
+                } else {
+                    targetGeogCRS->ellipsoid()->_exportToPROJString(formatter);
+                    targetGeogCRS->primeMeridian()->_exportToPROJString(
+                        formatter);
+                }
+            }
+        }
+
+        auto projCRS =
+            dynamic_cast<const crs::ProjectedCRS *>(l_targetCRS.get());
+        if (projCRS) {
+            projCRS->addUnitConvertAndAxisSwap(formatter, bAxisSpecFound);
+        }
+
+        auto derivedGeographicCRS =
+            dynamic_cast<const crs::DerivedGeographicCRS *>(l_targetCRS.get());
+        if (derivedGeographicCRS) {
+            if (formatter->convention() ==
+                io::PROJStringFormatter::Convention::PROJ_5) {
+                auto geogCRS = derivedGeographicCRS->baseCRS();
+                formatter->setOmitProjLongLatIfPossible(true);
+                geogCRS->_exportToPROJString(formatter);
+                formatter->setOmitProjLongLatIfPossible(false);
+            }
+        }
+    }
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return whether a conversion is a [Universal Transverse Mercator]
+ * (https://proj4.org/operations/projections/utm.html) conversion.
+ *
+ * @param[out] zone UTM zone number between 1 and 60.
+ * @param[out] north true for UTM northern hemisphere, false for UTM southern
+ * hemisphere.
+ * @return true if it is a UTM conversion.
+ */
+bool Conversion::isUTM(int &zone, bool &north) const {
+    zone = 0;
+    north = true;
+
+    if (method()->getEPSGCode() == EPSG_CODE_METHOD_TRANSVERSE_MERCATOR) {
+        // Check for UTM
+
+        bool bLatitudeNatOriginUTM = false;
+        bool bScaleFactorUTM = false;
+        bool bFalseEastingUTM = false;
+        bool bFalseNorthingUTM = false;
+        for (const auto &genOpParamvalue : parameterValues()) {
+            auto opParamvalue = dynamic_cast<const OperationParameterValue *>(
+                genOpParamvalue.get());
+            if (opParamvalue) {
+                const auto epsg_code = opParamvalue->parameter()->getEPSGCode();
+                const auto &l_parameterValue = opParamvalue->parameterValue();
+                if (l_parameterValue->type() == ParameterValue::Type::MEASURE) {
+                    const auto &measure = l_parameterValue->value();
+                    if (epsg_code ==
+                            EPSG_CODE_PARAMETER_LATITUDE_OF_NATURAL_ORIGIN &&
+                        std::fabs(measure.value() -
+                                  UTM_LATITUDE_OF_NATURAL_ORIGIN) < 1e-10) {
+                        bLatitudeNatOriginUTM = true;
+                    } else if (
+                        (epsg_code ==
+                             EPSG_CODE_PARAMETER_LONGITUDE_OF_NATURAL_ORIGIN ||
+                         epsg_code ==
+                             EPSG_CODE_PARAMETER_LONGITUDE_OF_ORIGIN) &&
+                        measure.unit()._isEquivalentTo(
+                            common::UnitOfMeasure::DEGREE,
+                            util::IComparable::Criterion::EQUIVALENT)) {
+                        double dfZone = (measure.value() + 183.0) / 6.0;
+                        if (dfZone > 0.9 && dfZone < 60.1 &&
+                            std::abs(dfZone - std::round(dfZone)) < 1e-10) {
+                            zone = static_cast<int>(std::lround(dfZone));
+                        }
+                    } else if (
+                        epsg_code ==
+                            EPSG_CODE_PARAMETER_SCALE_FACTOR_AT_NATURAL_ORIGIN &&
+                        measure.unit()._isEquivalentTo(
+                            common::UnitOfMeasure::SCALE_UNITY,
+                            util::IComparable::Criterion::EQUIVALENT) &&
+                        std::fabs(measure.value() - UTM_SCALE_FACTOR) < 1e-10) {
+                        bScaleFactorUTM = true;
+                    } else if (epsg_code == EPSG_CODE_PARAMETER_FALSE_EASTING &&
+                               measure.value() == UTM_FALSE_EASTING &&
+                               measure.unit()._isEquivalentTo(
+                                   common::UnitOfMeasure::METRE,
+                                   util::IComparable::Criterion::EQUIVALENT)) {
+                        bFalseEastingUTM = true;
+                    } else if (epsg_code ==
+                                   EPSG_CODE_PARAMETER_FALSE_NORTHING &&
+                               measure.unit()._isEquivalentTo(
+                                   common::UnitOfMeasure::METRE,
+                                   util::IComparable::Criterion::EQUIVALENT)) {
+                        if (std::fabs(measure.value() -
+                                      UTM_NORTH_FALSE_NORTHING) < 1e-10) {
+                            bFalseNorthingUTM = true;
+                            north = true;
+                        } else if (std::fabs(measure.value() -
+                                             UTM_SOUTH_FALSE_NORTHING) <
+                                   1e-10) {
+                            bFalseNorthingUTM = true;
+                            north = false;
+                        }
+                    }
+                }
+            }
+        }
+        if (bLatitudeNatOriginUTM && zone > 0 && bScaleFactorUTM &&
+            bFalseEastingUTM && bFalseNorthingUTM) {
+            return true;
+        }
+    }
+    return false;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return a Conversion object where some parameters are better
+ * identified.
+ *
+ * @return a new Conversion.
+ */
+ConversionNNPtr Conversion::identify() const {
+    auto newConversion = Conversion::nn_make_shared<Conversion>(*this);
+    newConversion->assignSelf(newConversion);
+
+    if (method()->getEPSGCode() == EPSG_CODE_METHOD_TRANSVERSE_MERCATOR) {
+        // Check for UTM
+        int zone = 0;
+        bool north = true;
+        if (isUTM(zone, north)) {
+            newConversion->setProperties(
+                getUTMConversionProperty(util::PropertyMap(), zone, north));
+        }
+    }
+
+    return newConversion;
+}
+
+//! @cond Doxygen_Suppress
+// ---------------------------------------------------------------------------
+
+InvalidOperation::InvalidOperation(const char *message) : Exception(message) {}
+
+// ---------------------------------------------------------------------------
+
+InvalidOperation::InvalidOperation(const std::string &message)
+    : Exception(message) {}
+
+// ---------------------------------------------------------------------------
+
+InvalidOperation::InvalidOperation(const InvalidOperation &) = default;
+
+// ---------------------------------------------------------------------------
+
+InvalidOperation::~InvalidOperation() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct Transformation::Private {
+
+    TransformationPtr forwardOperation_{};
+
+    TransformationNNPtr registerInv(util::BaseObjectNNPtr thisIn,
+                                    TransformationNNPtr invTransform);
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+Transformation::Transformation(
+    const crs::CRSNNPtr &sourceCRSIn, const crs::CRSNNPtr &targetCRSIn,
+    const crs::CRSPtr &interpolationCRSIn, const OperationMethodNNPtr &methodIn,
+    const std::vector<GeneralParameterValueNNPtr> &values,
+    const std::vector<metadata::PositionalAccuracyNNPtr> &accuracies)
+    : SingleOperation(methodIn), d(internal::make_unique<Private>()) {
+    setParameterValues(values);
+    setCRSs(sourceCRSIn, targetCRSIn, interpolationCRSIn);
+    setAccuracies(accuracies);
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+Transformation::~Transformation() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+Transformation::Transformation(const Transformation &other)
+    : CoordinateOperation(other), SingleOperation(other),
+      d(internal::make_unique<Private>(*other.d)) {}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the source crs::CRS of the transformation.
+ *
+ * @return the source CRS.
+ */
+const crs::CRSNNPtr &Transformation::sourceCRS() PROJ_CONST_DEFN {
+    return CoordinateOperation::getPrivate()->strongRef_->sourceCRS_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the target crs::CRS of the transformation.
+ *
+ * @return the target CRS.
+ */
+const crs::CRSNNPtr &Transformation::targetCRS() PROJ_CONST_DEFN {
+    return CoordinateOperation::getPrivate()->strongRef_->targetCRS_;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+TransformationNNPtr Transformation::shallowClone() const {
+    auto conv = Transformation::nn_make_shared<Transformation>(*this);
+    conv->assignSelf(conv);
+    conv->setCRSs(this, false);
+    return conv;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+/** \brief Return the TOWGS84 parameters of the transformation.
+ *
+ * If this transformation uses Coordinate Frame Rotation, Position Vector
+ * transformation or Geocentric translations, a vector of 7 double values
+ * using the Position Vector convention (EPSG:9606) is returned. Those values
+ * can be used as the value of the WKT1 TOWGS84 parameter or
+ * PROJ +towgs84 parameter.
+ *
+ * @return a vector of 7 values if valid, otherwise a io::FormattingException
+ * is thrown.
+ * @throws io::FormattingException
+ */
+std::vector<double>
+Transformation::getTOWGS84Parameters() const // throw(io::FormattingException)
+{
+    // GDAL WKT1 assumes EPSG:9606 / Position Vector convention
+
+    bool sevenParamsTransform = false;
+    bool threeParamsTransform = false;
+    bool invertRotSigns = false;
+    const auto &l_method = method();
+    const auto &methodName = l_method->nameStr();
+    const int methodEPSGCode = l_method->getEPSGCode();
+    const auto paramCount = parameterValues().size();
+    if ((paramCount == 7 &&
+         ci_find(methodName, "Coordinate Frame") != std::string::npos) ||
+        methodEPSGCode == EPSG_CODE_METHOD_COORDINATE_FRAME_GEOCENTRIC ||
+        methodEPSGCode == EPSG_CODE_METHOD_COORDINATE_FRAME_GEOGRAPHIC_2D ||
+        methodEPSGCode == EPSG_CODE_METHOD_COORDINATE_FRAME_GEOGRAPHIC_3D) {
+        sevenParamsTransform = true;
+        invertRotSigns = true;
+    } else if ((paramCount == 7 &&
+                ci_find(methodName, "Position Vector") != std::string::npos) ||
+               methodEPSGCode == EPSG_CODE_METHOD_POSITION_VECTOR_GEOCENTRIC ||
+               methodEPSGCode ==
+                   EPSG_CODE_METHOD_POSITION_VECTOR_GEOGRAPHIC_2D ||
+               methodEPSGCode ==
+                   EPSG_CODE_METHOD_POSITION_VECTOR_GEOGRAPHIC_3D) {
+        sevenParamsTransform = true;
+        invertRotSigns = false;
+    } else if ((paramCount == 3 &&
+                ci_find(methodName, "Geocentric translations") !=
+                    std::string::npos) ||
+               methodEPSGCode ==
+                   EPSG_CODE_METHOD_GEOCENTRIC_TRANSLATION_GEOCENTRIC ||
+               methodEPSGCode ==
+                   EPSG_CODE_METHOD_GEOCENTRIC_TRANSLATION_GEOGRAPHIC_2D ||
+               methodEPSGCode ==
+                   EPSG_CODE_METHOD_GEOCENTRIC_TRANSLATION_GEOGRAPHIC_3D) {
+        threeParamsTransform = true;
+    }
+
+    if (threeParamsTransform || sevenParamsTransform) {
+        std::vector<double> params(7, 0.0);
+        bool foundX = false;
+        bool foundY = false;
+        bool foundZ = false;
+        bool foundRotX = false;
+        bool foundRotY = false;
+        bool foundRotZ = false;
+        bool foundScale = false;
+        const double rotSign = invertRotSigns ? -1.0 : 1.0;
+
+        const auto fixNegativeZero = [](double x) {
+            if (x == 0.0)
+                return 0.0;
+            return x;
+        };
+
+        for (const auto &genOpParamvalue : parameterValues()) {
+            auto opParamvalue = dynamic_cast<const OperationParameterValue *>(
+                genOpParamvalue.get());
+            if (opParamvalue) {
+                const auto &parameter = opParamvalue->parameter();
+                const auto epsg_code = parameter->getEPSGCode();
+                const auto &l_parameterValue = opParamvalue->parameterValue();
+                if (l_parameterValue->type() == ParameterValue::Type::MEASURE) {
+                    const auto &measure = l_parameterValue->value();
+                    if (epsg_code == EPSG_CODE_PARAMETER_X_AXIS_TRANSLATION) {
+                        params[0] = measure.getSIValue();
+                        foundX = true;
+                    } else if (epsg_code ==
+                               EPSG_CODE_PARAMETER_Y_AXIS_TRANSLATION) {
+                        params[1] = measure.getSIValue();
+                        foundY = true;
+                    } else if (epsg_code ==
+                               EPSG_CODE_PARAMETER_Z_AXIS_TRANSLATION) {
+                        params[2] = measure.getSIValue();
+                        foundZ = true;
+                    } else if (epsg_code ==
+                               EPSG_CODE_PARAMETER_X_AXIS_ROTATION) {
+                        params[3] = fixNegativeZero(
+                            rotSign *
+                            measure.convertToUnit(
+                                common::UnitOfMeasure::ARC_SECOND));
+                        foundRotX = true;
+                    } else if (epsg_code ==
+                               EPSG_CODE_PARAMETER_Y_AXIS_ROTATION) {
+                        params[4] = fixNegativeZero(
+                            rotSign *
+                            measure.convertToUnit(
+                                common::UnitOfMeasure::ARC_SECOND));
+                        foundRotY = true;
+                    } else if (epsg_code ==
+                               EPSG_CODE_PARAMETER_Z_AXIS_ROTATION) {
+                        params[5] = fixNegativeZero(
+                            rotSign *
+                            measure.convertToUnit(
+                                common::UnitOfMeasure::ARC_SECOND));
+                        foundRotZ = true;
+                    } else if (epsg_code ==
+                               EPSG_CODE_PARAMETER_SCALE_DIFFERENCE) {
+                        params[6] = measure.convertToUnit(
+                            common::UnitOfMeasure::PARTS_PER_MILLION);
+                        foundScale = true;
+                    }
+                }
+            }
+        }
+        if (foundX && foundY && foundZ &&
+            (threeParamsTransform ||
+             (foundRotX && foundRotY && foundRotZ && foundScale))) {
+            return params;
+        } else {
+            throw io::FormattingException(
+                "Missing required parameter values in transformation");
+        }
+    }
+
+#if 0
+    if (methodEPSGCode == EPSG_CODE_METHOD_GEOGRAPHIC2D_OFFSETS ||
+        methodEPSGCode == EPSG_CODE_METHOD_GEOGRAPHIC3D_OFFSETS) {
+        auto offsetLat =
+            parameterValueMeasure(EPSG_CODE_PARAMETER_LATITUDE_OFFSET);
+        auto offsetLong =
+            parameterValueMeasure(EPSG_CODE_PARAMETER_LONGITUDE_OFFSET);
+
+        auto offsetHeight =
+            parameterValueMeasure(EPSG_CODE_PARAMETER_VERTICAL_OFFSET);
+
+        if (offsetLat.getSIValue() == 0.0 && offsetLong.getSIValue() == 0.0 &&
+            offsetHeight.getSIValue() == 0.0) {
+            std::vector<double> params(7, 0.0);
+            return params;
+        }
+    }
+#endif
+
+    throw io::FormattingException(
+        "Transformation cannot be formatted as WKT1 TOWGS84 parameters");
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a transformation from a vector of GeneralParameterValue.
+ *
+ * @param properties See \ref general_properties. At minimum the name should be
+ * defined.
+ * @param sourceCRSIn Source CRS.
+ * @param targetCRSIn Target CRS.
+ * @param interpolationCRSIn Interpolation CRS (might be null)
+ * @param methodIn Operation method.
+ * @param values Vector of GeneralOperationParameterNNPtr.
+ * @param accuracies Vector of positional accuracy (might be empty).
+ * @return new Transformation.
+ * @throws InvalidOperation
+ */
+TransformationNNPtr Transformation::create(
+    const util::PropertyMap &properties, const crs::CRSNNPtr &sourceCRSIn,
+    const crs::CRSNNPtr &targetCRSIn, const crs::CRSPtr &interpolationCRSIn,
+    const OperationMethodNNPtr &methodIn,
+    const std::vector<GeneralParameterValueNNPtr> &values,
+    const std::vector<metadata::PositionalAccuracyNNPtr> &accuracies) {
+    if (methodIn->parameters().size() != values.size()) {
+        throw InvalidOperation(
+            "Inconsistent number of parameters and parameter values");
+    }
+    auto conv = Transformation::nn_make_shared<Transformation>(
+        sourceCRSIn, targetCRSIn, interpolationCRSIn, methodIn, values,
+        accuracies);
+    conv->assignSelf(conv);
+    conv->setProperties(properties);
+    return conv;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a transformation ands its OperationMethod.
+ *
+ * @param propertiesTransformation The \ref general_properties of the
+ * Transformation.
+ * At minimum the name should be defined.
+ * @param sourceCRSIn Source CRS.
+ * @param targetCRSIn Target CRS.
+ * @param interpolationCRSIn Interpolation CRS (might be null)
+ * @param propertiesOperationMethod The \ref general_properties of the
+ * OperationMethod.
+ * At minimum the name should be defined.
+ * @param parameters Vector of parameters of the operation method.
+ * @param values Vector of ParameterValueNNPtr. Constraint:
+ * values.size() == parameters.size()
+ * @param accuracies Vector of positional accuracy (might be empty).
+ * @return new Transformation.
+ * @throws InvalidOperation
+ */
+TransformationNNPtr
+Transformation::create(const util::PropertyMap &propertiesTransformation,
+                       const crs::CRSNNPtr &sourceCRSIn,
+                       const crs::CRSNNPtr &targetCRSIn,
+                       const crs::CRSPtr &interpolationCRSIn,
+                       const util::PropertyMap &propertiesOperationMethod,
+                       const std::vector<OperationParameterNNPtr> &parameters,
+                       const std::vector<ParameterValueNNPtr> &values,
+                       const std::vector<metadata::PositionalAccuracyNNPtr>
+                           &accuracies) // throw InvalidOperation
+{
+    OperationMethodNNPtr op(
+        OperationMethod::create(propertiesOperationMethod, parameters));
+
+    if (parameters.size() != values.size()) {
+        throw InvalidOperation(
+            "Inconsistent number of parameters and parameter values");
+    }
+    std::vector<GeneralParameterValueNNPtr> generalParameterValues;
+    generalParameterValues.reserve(values.size());
+    for (size_t i = 0; i < values.size(); i++) {
+        generalParameterValues.push_back(
+            OperationParameterValue::create(parameters[i], values[i]));
+    }
+    return create(propertiesTransformation, sourceCRSIn, targetCRSIn,
+                  interpolationCRSIn, op, generalParameterValues, accuracies);
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+// ---------------------------------------------------------------------------
+
+static TransformationNNPtr createSevenParamsTransform(
+    const util::PropertyMap &properties,
+    const util::PropertyMap &methodProperties, const crs::CRSNNPtr &sourceCRSIn,
+    const crs::CRSNNPtr &targetCRSIn, double translationXMetre,
+    double translationYMetre, double translationZMetre,
+    double rotationXArcSecond, double rotationYArcSecond,
+    double rotationZArcSecond, double scaleDifferencePPM,
+    const std::vector<metadata::PositionalAccuracyNNPtr> &accuracies) {
+    return Transformation::create(
+        properties, sourceCRSIn, targetCRSIn, nullptr, methodProperties,
+        VectorOfParameters{
+            createOpParamNameEPSGCode(EPSG_CODE_PARAMETER_X_AXIS_TRANSLATION),
+            createOpParamNameEPSGCode(EPSG_CODE_PARAMETER_Y_AXIS_TRANSLATION),
+            createOpParamNameEPSGCode(EPSG_CODE_PARAMETER_Z_AXIS_TRANSLATION),
+            createOpParamNameEPSGCode(EPSG_CODE_PARAMETER_X_AXIS_ROTATION),
+            createOpParamNameEPSGCode(EPSG_CODE_PARAMETER_Y_AXIS_ROTATION),
+            createOpParamNameEPSGCode(EPSG_CODE_PARAMETER_Z_AXIS_ROTATION),
+            createOpParamNameEPSGCode(EPSG_CODE_PARAMETER_SCALE_DIFFERENCE),
+        },
+        createParams(common::Length(translationXMetre),
+                     common::Length(translationYMetre),
+                     common::Length(translationZMetre),
+                     common::Angle(rotationXArcSecond,
+                                   common::UnitOfMeasure::ARC_SECOND),
+                     common::Angle(rotationYArcSecond,
+                                   common::UnitOfMeasure::ARC_SECOND),
+                     common::Angle(rotationZArcSecond,
+                                   common::UnitOfMeasure::ARC_SECOND),
+                     common::Scale(scaleDifferencePPM,
+                                   common::UnitOfMeasure::PARTS_PER_MILLION)),
+        accuracies);
+}
+
+// ---------------------------------------------------------------------------
+
+static void getTransformationType(const crs::CRSNNPtr &sourceCRSIn,
+                                  const crs::CRSNNPtr &targetCRSIn,
+                                  bool &isGeocentric, bool &isGeog2D,
+                                  bool &isGeog3D) {
+    auto sourceCRSGeod =
+        dynamic_cast<const crs::GeodeticCRS *>(sourceCRSIn.get());
+    auto targetCRSGeod =
+        dynamic_cast<const crs::GeodeticCRS *>(targetCRSIn.get());
+    isGeocentric = sourceCRSGeod && sourceCRSGeod->isGeocentric() &&
+                   targetCRSGeod && targetCRSGeod->isGeocentric();
+    if (isGeocentric) {
+        isGeog2D = false;
+        isGeog3D = false;
+        return;
+    }
+    isGeocentric = false;
+
+    auto sourceCRSGeog =
+        dynamic_cast<const crs::GeographicCRS *>(sourceCRSIn.get());
+    auto targetCRSGeog =
+        dynamic_cast<const crs::GeographicCRS *>(targetCRSIn.get());
+    if (!sourceCRSGeog || !targetCRSGeog) {
+        throw InvalidOperation("Inconsistent CRS type");
+    }
+    const auto nSrcAxisCount =
+        sourceCRSGeog->coordinateSystem()->axisList().size();
+    const auto nTargetAxisCount =
+        targetCRSGeog->coordinateSystem()->axisList().size();
+    isGeog2D = nSrcAxisCount == 2 && nTargetAxisCount == 2;
+    isGeog3D = !isGeog2D && nSrcAxisCount >= 2 && nTargetAxisCount >= 2;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a transformation with Geocentric Translations method.
+ *
+ * @param properties See \ref general_properties of the Transformation.
+ * At minimum the name should be defined.
+ * @param sourceCRSIn Source CRS.
+ * @param targetCRSIn Target CRS.
+ * @param translationXMetre Value of the Translation_X parameter (in metre).
+ * @param translationYMetre Value of the Translation_Y parameter (in metre).
+ * @param translationZMetre Value of the Translation_Z parameter (in metre).
+ * @param accuracies Vector of positional accuracy (might be empty).
+ * @return new Transformation.
+ */
+TransformationNNPtr Transformation::createGeocentricTranslations(
+    const util::PropertyMap &properties, const crs::CRSNNPtr &sourceCRSIn,
+    const crs::CRSNNPtr &targetCRSIn, double translationXMetre,
+    double translationYMetre, double translationZMetre,
+    const std::vector<metadata::PositionalAccuracyNNPtr> &accuracies) {
+    bool isGeocentric;
+    bool isGeog2D;
+    bool isGeog3D;
+    getTransformationType(sourceCRSIn, targetCRSIn, isGeocentric, isGeog2D,
+                          isGeog3D);
+    return create(
+        properties, sourceCRSIn, targetCRSIn, nullptr,
+        createMethodMapNameEPSGCode(
+            isGeocentric
+                ? EPSG_CODE_METHOD_GEOCENTRIC_TRANSLATION_GEOCENTRIC
+                : isGeog2D
+                      ? EPSG_CODE_METHOD_GEOCENTRIC_TRANSLATION_GEOGRAPHIC_2D
+                      : EPSG_CODE_METHOD_GEOCENTRIC_TRANSLATION_GEOGRAPHIC_3D),
+        VectorOfParameters{
+            createOpParamNameEPSGCode(EPSG_CODE_PARAMETER_X_AXIS_TRANSLATION),
+            createOpParamNameEPSGCode(EPSG_CODE_PARAMETER_Y_AXIS_TRANSLATION),
+            createOpParamNameEPSGCode(EPSG_CODE_PARAMETER_Z_AXIS_TRANSLATION),
+        },
+        createParams(common::Length(translationXMetre),
+                     common::Length(translationYMetre),
+                     common::Length(translationZMetre)),
+        accuracies);
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a transformation with Position vector transformation
+ * method.
+ *
+ * This is similar to createCoordinateFrameRotation(), except that the sign of
+ * the rotation terms is inverted.
+ *
+ * @param properties See \ref general_properties of the Transformation.
+ * At minimum the name should be defined.
+ * @param sourceCRSIn Source CRS.
+ * @param targetCRSIn Target CRS.
+ * @param translationXMetre Value of the Translation_X parameter (in metre).
+ * @param translationYMetre Value of the Translation_Y parameter (in metre).
+ * @param translationZMetre Value of the Translation_Z parameter (in metre).
+ * @param rotationXArcSecond Value of the Rotation_X parameter (in
+ * arc-second).
+ * @param rotationYArcSecond Value of the Rotation_Y parameter (in
+ * arc-second).
+ * @param rotationZArcSecond Value of the Rotation_Z parameter (in
+ * arc-second).
+ * @param scaleDifferencePPM Value of the Scale_Difference parameter (in
+ * parts-per-million).
+ * @param accuracies Vector of positional accuracy (might be empty).
+ * @return new Transformation.
+ */
+TransformationNNPtr Transformation::createPositionVector(
+    const util::PropertyMap &properties, const crs::CRSNNPtr &sourceCRSIn,
+    const crs::CRSNNPtr &targetCRSIn, double translationXMetre,
+    double translationYMetre, double translationZMetre,
+    double rotationXArcSecond, double rotationYArcSecond,
+    double rotationZArcSecond, double scaleDifferencePPM,
+    const std::vector<metadata::PositionalAccuracyNNPtr> &accuracies) {
+
+    bool isGeocentric;
+    bool isGeog2D;
+    bool isGeog3D;
+    getTransformationType(sourceCRSIn, targetCRSIn, isGeocentric, isGeog2D,
+                          isGeog3D);
+    return createSevenParamsTransform(
+        properties,
+        createMethodMapNameEPSGCode(
+            isGeocentric
+                ? EPSG_CODE_METHOD_POSITION_VECTOR_GEOCENTRIC
+                : isGeog2D ? EPSG_CODE_METHOD_POSITION_VECTOR_GEOGRAPHIC_2D
+                           : EPSG_CODE_METHOD_POSITION_VECTOR_GEOGRAPHIC_3D),
+        sourceCRSIn, targetCRSIn, translationXMetre, translationYMetre,
+        translationZMetre, rotationXArcSecond, rotationYArcSecond,
+        rotationZArcSecond, scaleDifferencePPM, accuracies);
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a transformation with Coordinate Frame Rotation method.
+ *
+ * This is similar to createPositionVector(), except that the sign of
+ * the rotation terms is inverted.
+ *
+ * @param properties See \ref general_properties of the Transformation.
+ * At minimum the name should be defined.
+ * @param sourceCRSIn Source CRS.
+ * @param targetCRSIn Target CRS.
+ * @param translationXMetre Value of the Translation_X parameter (in metre).
+ * @param translationYMetre Value of the Translation_Y parameter (in metre).
+ * @param translationZMetre Value of the Translation_Z parameter (in metre).
+ * @param rotationXArcSecond Value of the Rotation_X parameter (in
+ * arc-second).
+ * @param rotationYArcSecond Value of the Rotation_Y parameter (in
+ * arc-second).
+ * @param rotationZArcSecond Value of the Rotation_Z parameter (in
+ * arc-second).
+ * @param scaleDifferencePPM Value of the Scale_Difference parameter (in
+ * parts-per-million).
+ * @param accuracies Vector of positional accuracy (might be empty).
+ * @return new Transformation.
+ */
+TransformationNNPtr Transformation::createCoordinateFrameRotation(
+    const util::PropertyMap &properties, const crs::CRSNNPtr &sourceCRSIn,
+    const crs::CRSNNPtr &targetCRSIn, double translationXMetre,
+    double translationYMetre, double translationZMetre,
+    double rotationXArcSecond, double rotationYArcSecond,
+    double rotationZArcSecond, double scaleDifferencePPM,
+    const std::vector<metadata::PositionalAccuracyNNPtr> &accuracies) {
+    bool isGeocentric;
+    bool isGeog2D;
+    bool isGeog3D;
+    getTransformationType(sourceCRSIn, targetCRSIn, isGeocentric, isGeog2D,
+                          isGeog3D);
+    return createSevenParamsTransform(
+        properties,
+        createMethodMapNameEPSGCode(
+            isGeocentric
+                ? EPSG_CODE_METHOD_COORDINATE_FRAME_GEOCENTRIC
+                : isGeog2D ? EPSG_CODE_METHOD_COORDINATE_FRAME_GEOGRAPHIC_2D
+                           : EPSG_CODE_METHOD_COORDINATE_FRAME_GEOGRAPHIC_3D),
+        sourceCRSIn, targetCRSIn, translationXMetre, translationYMetre,
+        translationZMetre, rotationXArcSecond, rotationYArcSecond,
+        rotationZArcSecond, scaleDifferencePPM, accuracies);
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static TransformationNNPtr createFifteenParamsTransform(
+    const util::PropertyMap &properties,
+    const util::PropertyMap &methodProperties, const crs::CRSNNPtr &sourceCRSIn,
+    const crs::CRSNNPtr &targetCRSIn, double translationXMetre,
+    double translationYMetre, double translationZMetre,
+    double rotationXArcSecond, double rotationYArcSecond,
+    double rotationZArcSecond, double scaleDifferencePPM,
+    double rateTranslationX, double rateTranslationY, double rateTranslationZ,
+    double rateRotationX, double rateRotationY, double rateRotationZ,
+    double rateScaleDifference, double referenceEpochYear,
+    const std::vector<metadata::PositionalAccuracyNNPtr> &accuracies) {
+    return Transformation::create(
+        properties, sourceCRSIn, targetCRSIn, nullptr, methodProperties,
+        VectorOfParameters{
+            createOpParamNameEPSGCode(EPSG_CODE_PARAMETER_X_AXIS_TRANSLATION),
+            createOpParamNameEPSGCode(EPSG_CODE_PARAMETER_Y_AXIS_TRANSLATION),
+            createOpParamNameEPSGCode(EPSG_CODE_PARAMETER_Z_AXIS_TRANSLATION),
+            createOpParamNameEPSGCode(EPSG_CODE_PARAMETER_X_AXIS_ROTATION),
+            createOpParamNameEPSGCode(EPSG_CODE_PARAMETER_Y_AXIS_ROTATION),
+            createOpParamNameEPSGCode(EPSG_CODE_PARAMETER_Z_AXIS_ROTATION),
+            createOpParamNameEPSGCode(EPSG_CODE_PARAMETER_SCALE_DIFFERENCE),
+
+            createOpParamNameEPSGCode(
+                EPSG_CODE_PARAMETER_RATE_X_AXIS_TRANSLATION),
+            createOpParamNameEPSGCode(
+                EPSG_CODE_PARAMETER_RATE_Y_AXIS_TRANSLATION),
+            createOpParamNameEPSGCode(
+                EPSG_CODE_PARAMETER_RATE_Z_AXIS_TRANSLATION),
+            createOpParamNameEPSGCode(EPSG_CODE_PARAMETER_RATE_X_AXIS_ROTATION),
+            createOpParamNameEPSGCode(EPSG_CODE_PARAMETER_RATE_Y_AXIS_ROTATION),
+            createOpParamNameEPSGCode(EPSG_CODE_PARAMETER_RATE_Z_AXIS_ROTATION),
+            createOpParamNameEPSGCode(
+                EPSG_CODE_PARAMETER_RATE_SCALE_DIFFERENCE),
+
+            createOpParamNameEPSGCode(EPSG_CODE_PARAMETER_REFERENCE_EPOCH),
+        },
+        VectorOfValues{
+            common::Length(translationXMetre),
+            common::Length(translationYMetre),
+            common::Length(translationZMetre),
+            common::Angle(rotationXArcSecond,
+                          common::UnitOfMeasure::ARC_SECOND),
+            common::Angle(rotationYArcSecond,
+                          common::UnitOfMeasure::ARC_SECOND),
+            common::Angle(rotationZArcSecond,
+                          common::UnitOfMeasure::ARC_SECOND),
+            common::Scale(scaleDifferencePPM,
+                          common::UnitOfMeasure::PARTS_PER_MILLION),
+            common::Measure(rateTranslationX,
+                            common::UnitOfMeasure::METRE_PER_YEAR),
+            common::Measure(rateTranslationY,
+                            common::UnitOfMeasure::METRE_PER_YEAR),
+            common::Measure(rateTranslationZ,
+                            common::UnitOfMeasure::METRE_PER_YEAR),
+            common::Measure(rateRotationX,
+                            common::UnitOfMeasure::ARC_SECOND_PER_YEAR),
+            common::Measure(rateRotationY,
+                            common::UnitOfMeasure::ARC_SECOND_PER_YEAR),
+            common::Measure(rateRotationZ,
+                            common::UnitOfMeasure::ARC_SECOND_PER_YEAR),
+            common::Measure(rateScaleDifference,
+                            common::UnitOfMeasure::PPM_PER_YEAR),
+            common::Measure(referenceEpochYear, common::UnitOfMeasure::YEAR),
+        },
+        accuracies);
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a transformation with Time Dependent position vector
+ * transformation method.
+ *
+ * This is similar to createTimeDependentCoordinateFrameRotation(), except that
+ * the sign of
+ * the rotation terms is inverted.
+ *
+ * This method is defined as [EPSG:1053]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::1053)
+ *
+ * @param properties See \ref general_properties of the Transformation.
+ * At minimum the name should be defined.
+ * @param sourceCRSIn Source CRS.
+ * @param targetCRSIn Target CRS.
+ * @param translationXMetre Value of the Translation_X parameter (in metre).
+ * @param translationYMetre Value of the Translation_Y parameter (in metre).
+ * @param translationZMetre Value of the Translation_Z parameter (in metre).
+ * @param rotationXArcSecond Value of the Rotation_X parameter (in
+ * arc-second).
+ * @param rotationYArcSecond Value of the Rotation_Y parameter (in
+ * arc-second).
+ * @param rotationZArcSecond Value of the Rotation_Z parameter (in
+ * arc-second).
+ * @param scaleDifferencePPM Value of the Scale_Difference parameter (in
+ * parts-per-million).
+ * @param rateTranslationX Value of the rate of change of X-axis translation (in
+ * metre/year)
+ * @param rateTranslationY Value of the rate of change of Y-axis translation (in
+ * metre/year)
+ * @param rateTranslationZ Value of the rate of change of Z-axis translation (in
+ * metre/year)
+ * @param rateRotationX Value of the rate of change of X-axis rotation (in
+ * arc-second/year)
+ * @param rateRotationY Value of the rate of change of Y-axis rotation (in
+ * arc-second/year)
+ * @param rateRotationZ Value of the rate of change of Z-axis rotation (in
+ * arc-second/year)
+ * @param rateScaleDifference Value of the rate of change of scale difference
+ * (in PPM/year)
+ * @param referenceEpochYear Parameter reference epoch (in decimal year)
+ * @param accuracies Vector of positional accuracy (might be empty).
+ * @return new Transformation.
+ */
+TransformationNNPtr Transformation::createTimeDependentPositionVector(
+    const util::PropertyMap &properties, const crs::CRSNNPtr &sourceCRSIn,
+    const crs::CRSNNPtr &targetCRSIn, double translationXMetre,
+    double translationYMetre, double translationZMetre,
+    double rotationXArcSecond, double rotationYArcSecond,
+    double rotationZArcSecond, double scaleDifferencePPM,
+    double rateTranslationX, double rateTranslationY, double rateTranslationZ,
+    double rateRotationX, double rateRotationY, double rateRotationZ,
+    double rateScaleDifference, double referenceEpochYear,
+    const std::vector<metadata::PositionalAccuracyNNPtr> &accuracies) {
+    bool isGeocentric;
+    bool isGeog2D;
+    bool isGeog3D;
+    getTransformationType(sourceCRSIn, targetCRSIn, isGeocentric, isGeog2D,
+                          isGeog3D);
+    return createFifteenParamsTransform(
+        properties,
+        createMethodMapNameEPSGCode(
+            isGeocentric
+                ? EPSG_CODE_METHOD_TIME_DEPENDENT_POSITION_VECTOR_GEOCENTRIC
+                : isGeog2D
+                      ? EPSG_CODE_METHOD_TIME_DEPENDENT_POSITION_VECTOR_GEOGRAPHIC_2D
+                      : EPSG_CODE_METHOD_TIME_DEPENDENT_POSITION_VECTOR_GEOGRAPHIC_3D),
+        sourceCRSIn, targetCRSIn, translationXMetre, translationYMetre,
+        translationZMetre, rotationXArcSecond, rotationYArcSecond,
+        rotationZArcSecond, scaleDifferencePPM, rateTranslationX,
+        rateTranslationY, rateTranslationZ, rateRotationX, rateRotationY,
+        rateRotationZ, rateScaleDifference, referenceEpochYear, accuracies);
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a transformation with Time Dependent Position coordinate
+ * frame rotation transformation method.
+ *
+ * This is similar to createTimeDependentPositionVector(), except that the sign
+ * of
+ * the rotation terms is inverted.
+ *
+ * This method is defined as [EPSG:1056]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::1056)
+ *
+ * @param properties See \ref general_properties of the Transformation.
+ * At minimum the name should be defined.
+ * @param sourceCRSIn Source CRS.
+ * @param targetCRSIn Target CRS.
+ * @param translationXMetre Value of the Translation_X parameter (in metre).
+ * @param translationYMetre Value of the Translation_Y parameter (in metre).
+ * @param translationZMetre Value of the Translation_Z parameter (in metre).
+ * @param rotationXArcSecond Value of the Rotation_X parameter (in
+ * arc-second).
+ * @param rotationYArcSecond Value of the Rotation_Y parameter (in
+ * arc-second).
+ * @param rotationZArcSecond Value of the Rotation_Z parameter (in
+ * arc-second).
+ * @param scaleDifferencePPM Value of the Scale_Difference parameter (in
+ * parts-per-million).
+ * @param rateTranslationX Value of the rate of change of X-axis translation (in
+ * metre/year)
+ * @param rateTranslationY Value of the rate of change of Y-axis translation (in
+ * metre/year)
+ * @param rateTranslationZ Value of the rate of change of Z-axis translation (in
+ * metre/year)
+ * @param rateRotationX Value of the rate of change of X-axis rotation (in
+ * arc-second/year)
+ * @param rateRotationY Value of the rate of change of Y-axis rotation (in
+ * arc-second/year)
+ * @param rateRotationZ Value of the rate of change of Z-axis rotation (in
+ * arc-second/year)
+ * @param rateScaleDifference Value of the rate of change of scale difference
+ * (in PPM/year)
+ * @param referenceEpochYear Parameter reference epoch (in decimal year)
+ * @param accuracies Vector of positional accuracy (might be empty).
+ * @return new Transformation.
+ * @throws InvalidOperation
+ */
+TransformationNNPtr Transformation::createTimeDependentCoordinateFrameRotation(
+    const util::PropertyMap &properties, const crs::CRSNNPtr &sourceCRSIn,
+    const crs::CRSNNPtr &targetCRSIn, double translationXMetre,
+    double translationYMetre, double translationZMetre,
+    double rotationXArcSecond, double rotationYArcSecond,
+    double rotationZArcSecond, double scaleDifferencePPM,
+    double rateTranslationX, double rateTranslationY, double rateTranslationZ,
+    double rateRotationX, double rateRotationY, double rateRotationZ,
+    double rateScaleDifference, double referenceEpochYear,
+    const std::vector<metadata::PositionalAccuracyNNPtr> &accuracies) {
+
+    bool isGeocentric;
+    bool isGeog2D;
+    bool isGeog3D;
+    getTransformationType(sourceCRSIn, targetCRSIn, isGeocentric, isGeog2D,
+                          isGeog3D);
+    return createFifteenParamsTransform(
+        properties,
+        createMethodMapNameEPSGCode(
+            isGeocentric
+                ? EPSG_CODE_METHOD_TIME_DEPENDENT_COORDINATE_FRAME_GEOCENTRIC
+                : isGeog2D
+                      ? EPSG_CODE_METHOD_TIME_DEPENDENT_COORDINATE_FRAME_GEOGRAPHIC_2D
+                      : EPSG_CODE_METHOD_TIME_DEPENDENT_COORDINATE_FRAME_GEOGRAPHIC_3D),
+        sourceCRSIn, targetCRSIn, translationXMetre, translationYMetre,
+        translationZMetre, rotationXArcSecond, rotationYArcSecond,
+        rotationZArcSecond, scaleDifferencePPM, rateTranslationX,
+        rateTranslationY, rateTranslationZ, rateRotationX, rateRotationY,
+        rateRotationZ, rateScaleDifference, referenceEpochYear, accuracies);
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static TransformationNNPtr _createMolodensky(
+    const util::PropertyMap &properties, const crs::CRSNNPtr &sourceCRSIn,
+    const crs::CRSNNPtr &targetCRSIn, int methodEPSGCode,
+    double translationXMetre, double translationYMetre,
+    double translationZMetre, double semiMajorAxisDifferenceMetre,
+    double flattingDifference,
+    const std::vector<metadata::PositionalAccuracyNNPtr> &accuracies) {
+    return Transformation::create(
+        properties, sourceCRSIn, targetCRSIn, nullptr,
+        createMethodMapNameEPSGCode(methodEPSGCode),
+        VectorOfParameters{
+            createOpParamNameEPSGCode(EPSG_CODE_PARAMETER_X_AXIS_TRANSLATION),
+            createOpParamNameEPSGCode(EPSG_CODE_PARAMETER_Y_AXIS_TRANSLATION),
+            createOpParamNameEPSGCode(EPSG_CODE_PARAMETER_Z_AXIS_TRANSLATION),
+            createOpParamNameEPSGCode(
+                EPSG_CODE_PARAMETER_SEMI_MAJOR_AXIS_DIFFERENCE),
+            createOpParamNameEPSGCode(
+                EPSG_CODE_PARAMETER_FLATTENING_DIFFERENCE),
+        },
+        createParams(
+            common::Length(translationXMetre),
+            common::Length(translationYMetre),
+            common::Length(translationZMetre),
+            common::Length(semiMajorAxisDifferenceMetre),
+            common::Measure(flattingDifference, common::UnitOfMeasure::NONE)),
+        accuracies);
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a transformation with Molodensky method.
+ *
+ * @see createAbridgedMolodensky() for a related method.
+ *
+ * This method is defined as [EPSG:9604]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9604)
+ *
+ * @param properties See \ref general_properties of the Transformation.
+ * At minimum the name should be defined.
+ * @param sourceCRSIn Source CRS.
+ * @param targetCRSIn Target CRS.
+ * @param translationXMetre Value of the Translation_X parameter (in metre).
+ * @param translationYMetre Value of the Translation_Y parameter (in metre).
+ * @param translationZMetre Value of the Translation_Z parameter (in metre).
+ * @param semiMajorAxisDifferenceMetre The difference between the semi-major
+ * axis values of the ellipsoids used in the target and source CRS (in metre).
+ * @param flattingDifference The difference  between the flattening values of
+ * the ellipsoids used in the target and source CRS.
+ * @param accuracies Vector of positional accuracy (might be empty).
+ * @return new Transformation.
+ * @throws InvalidOperation
+ */
+TransformationNNPtr Transformation::createMolodensky(
+    const util::PropertyMap &properties, const crs::CRSNNPtr &sourceCRSIn,
+    const crs::CRSNNPtr &targetCRSIn, double translationXMetre,
+    double translationYMetre, double translationZMetre,
+    double semiMajorAxisDifferenceMetre, double flattingDifference,
+    const std::vector<metadata::PositionalAccuracyNNPtr> &accuracies) {
+    return _createMolodensky(
+        properties, sourceCRSIn, targetCRSIn, EPSG_CODE_METHOD_MOLODENSKY,
+        translationXMetre, translationYMetre, translationZMetre,
+        semiMajorAxisDifferenceMetre, flattingDifference, accuracies);
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a transformation with Abridged Molodensky method.
+ *
+ * @see createdMolodensky() for a related method.
+ *
+ * This method is defined as [EPSG:9605]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9605)
+ *
+ * @param properties See \ref general_properties of the Transformation.
+ * At minimum the name should be defined.
+ * @param sourceCRSIn Source CRS.
+ * @param targetCRSIn Target CRS.
+ * @param translationXMetre Value of the Translation_X parameter (in metre).
+ * @param translationYMetre Value of the Translation_Y parameter (in metre).
+ * @param translationZMetre Value of the Translation_Z parameter (in metre).
+ * @param semiMajorAxisDifferenceMetre The difference between the semi-major
+ * axis values of the ellipsoids used in the target and source CRS (in metre).
+ * @param flattingDifference The difference  between the flattening values of
+ * the ellipsoids used in the target and source CRS.
+ * @param accuracies Vector of positional accuracy (might be empty).
+ * @return new Transformation.
+ * @throws InvalidOperation
+ */
+TransformationNNPtr Transformation::createAbridgedMolodensky(
+    const util::PropertyMap &properties, const crs::CRSNNPtr &sourceCRSIn,
+    const crs::CRSNNPtr &targetCRSIn, double translationXMetre,
+    double translationYMetre, double translationZMetre,
+    double semiMajorAxisDifferenceMetre, double flattingDifference,
+    const std::vector<metadata::PositionalAccuracyNNPtr> &accuracies) {
+    return _createMolodensky(properties, sourceCRSIn, targetCRSIn,
+                             EPSG_CODE_METHOD_ABRIDGED_MOLODENSKY,
+                             translationXMetre, translationYMetre,
+                             translationZMetre, semiMajorAxisDifferenceMetre,
+                             flattingDifference, accuracies);
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a transformation from TOWGS84 parameters.
+ *
+ * This is a helper of createPositionVector() with the source CRS being the
+ * GeographicCRS of sourceCRSIn, and the target CRS being EPSG:4326
+ *
+ * @param sourceCRSIn Source CRS.
+ * @param TOWGS84Parameters The vector of 3 double values (Translation_X,_Y,_Z)
+ * or 7 double values (Translation_X,_Y,_Z, Rotation_X,_Y,_Z, Scale_Difference)
+ * passed to createPositionVector()
+ * @return new Transformation.
+ * @throws InvalidOperation
+ */
+TransformationNNPtr Transformation::createTOWGS84(
+    const crs::CRSNNPtr &sourceCRSIn,
+    const std::vector<double> &TOWGS84Parameters) // throw InvalidOperation
+{
+    if (TOWGS84Parameters.size() != 3 && TOWGS84Parameters.size() != 7) {
+        throw InvalidOperation(
+            "Invalid number of elements in TOWGS84Parameters");
+    }
+
+    crs::CRSPtr transformSourceCRS = sourceCRSIn->extractGeodeticCRS();
+    if (!transformSourceCRS) {
+        throw InvalidOperation(
+            "Cannot find GeodeticCRS in sourceCRS of TOWGS84 transformation");
+    }
+
+    util::PropertyMap properties;
+    properties.set(common::IdentifiedObject::NAME_KEY,
+                   concat("Transformation from ", transformSourceCRS->nameStr(),
+                          " to WGS84"));
+
+    auto targetCRS =
+        dynamic_cast<const crs::GeographicCRS *>(transformSourceCRS.get())
+            ? util::nn_static_pointer_cast<crs::CRS>(
+                  crs::GeographicCRS::EPSG_4326)
+            : util::nn_static_pointer_cast<crs::CRS>(
+                  crs::GeodeticCRS::EPSG_4978);
+
+    if (TOWGS84Parameters.size() == 3) {
+        return createGeocentricTranslations(
+            properties, NN_NO_CHECK(transformSourceCRS), targetCRS,
+            TOWGS84Parameters[0], TOWGS84Parameters[1], TOWGS84Parameters[2],
+            {});
+    }
+
+    return createPositionVector(properties, NN_NO_CHECK(transformSourceCRS),
+                                targetCRS, TOWGS84Parameters[0],
+                                TOWGS84Parameters[1], TOWGS84Parameters[2],
+                                TOWGS84Parameters[3], TOWGS84Parameters[4],
+                                TOWGS84Parameters[5], TOWGS84Parameters[6], {});
+}
+
+// ---------------------------------------------------------------------------
+/** \brief Instanciate a transformation with NTv2 method.
+ *
+ * @param properties See \ref general_properties of the Transformation.
+ * At minimum the name should be defined.
+ * @param sourceCRSIn Source CRS.
+ * @param targetCRSIn Target CRS.
+ * @param filename NTv2 filename.
+ * @param accuracies Vector of positional accuracy (might be empty).
+ * @return new Transformation.
+ */
+TransformationNNPtr Transformation::createNTv2(
+    const util::PropertyMap &properties, const crs::CRSNNPtr &sourceCRSIn,
+    const crs::CRSNNPtr &targetCRSIn, const std::string &filename,
+    const std::vector<metadata::PositionalAccuracyNNPtr> &accuracies) {
+
+    return create(properties, sourceCRSIn, targetCRSIn, nullptr,
+                  createMethodMapNameEPSGCode(EPSG_CODE_METHOD_NTV2),
+                  VectorOfParameters{createOpParamNameEPSGCode(
+                      EPSG_CODE_PARAMETER_LATITUDE_LONGITUDE_DIFFERENCE_FILE)},
+                  VectorOfValues{ParameterValue::createFilename(filename)},
+                  accuracies);
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static TransformationNNPtr _createGravityRelatedHeightToGeographic3D(
+    const util::PropertyMap &properties, bool inverse,
+    const crs::CRSNNPtr &sourceCRSIn, const crs::CRSNNPtr &targetCRSIn,
+    const std::string &filename,
+    const std::vector<metadata::PositionalAccuracyNNPtr> &accuracies) {
+
+    return Transformation::create(
+        properties, sourceCRSIn, targetCRSIn, nullptr,
+        util::PropertyMap().set(
+            common::IdentifiedObject::NAME_KEY,
+            inverse ? INVERSE_OF + PROJ_WKT2_NAME_METHOD_HEIGHT_TO_GEOG3D
+                    : PROJ_WKT2_NAME_METHOD_HEIGHT_TO_GEOG3D),
+        VectorOfParameters{createOpParamNameEPSGCode(
+            EPSG_CODE_PARAMETER_GEOID_CORRECTION_FILENAME)},
+        VectorOfValues{ParameterValue::createFilename(filename)}, accuracies);
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+/** \brief Instanciate a transformation from GravityRelatedHeight to
+ * Geographic3D
+ *
+ * @param properties See \ref general_properties of the Transformation.
+ * At minimum the name should be defined.
+ * @param sourceCRSIn Source CRS.
+ * @param targetCRSIn Target CRS.
+ * @param filename GRID filename.
+ * @param accuracies Vector of positional accuracy (might be empty).
+ * @return new Transformation.
+ */
+TransformationNNPtr Transformation::createGravityRelatedHeightToGeographic3D(
+    const util::PropertyMap &properties, const crs::CRSNNPtr &sourceCRSIn,
+    const crs::CRSNNPtr &targetCRSIn, const std::string &filename,
+    const std::vector<metadata::PositionalAccuracyNNPtr> &accuracies) {
+
+    return _createGravityRelatedHeightToGeographic3D(
+        properties, false, sourceCRSIn, targetCRSIn, filename, accuracies);
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a transformation with method VERTCON
+ *
+ * @param properties See \ref general_properties of the Transformation.
+ * At minimum the name should be defined.
+ * @param sourceCRSIn Source CRS.
+ * @param targetCRSIn Target CRS.
+ * @param filename GRID filename.
+ * @param accuracies Vector of positional accuracy (might be empty).
+ * @return new Transformation.
+ */
+TransformationNNPtr Transformation::createVERTCON(
+    const util::PropertyMap &properties, const crs::CRSNNPtr &sourceCRSIn,
+    const crs::CRSNNPtr &targetCRSIn, const std::string &filename,
+    const std::vector<metadata::PositionalAccuracyNNPtr> &accuracies) {
+
+    return create(properties, sourceCRSIn, targetCRSIn, nullptr,
+                  createMethodMapNameEPSGCode(EPSG_CODE_METHOD_VERTCON),
+                  VectorOfParameters{createOpParamNameEPSGCode(
+                      EPSG_CODE_PARAMETER_VERTICAL_OFFSET_FILE)},
+                  VectorOfValues{ParameterValue::createFilename(filename)},
+                  accuracies);
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static inline std::vector<metadata::PositionalAccuracyNNPtr>
+buildAccuracyZero() {
+    return std::vector<metadata::PositionalAccuracyNNPtr>{
+        metadata::PositionalAccuracy::create("0")};
+}
+
+// ---------------------------------------------------------------------------
+
+//! @endcond
+
+/** \brief Instanciate a transformation with method Longitude rotation
+ *
+ * This method is defined as [EPSG:9601]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9601)
+ * *
+ * @param properties See \ref general_properties of the Transformation.
+ * At minimum the name should be defined.
+ * @param sourceCRSIn Source CRS.
+ * @param targetCRSIn Target CRS.
+ * @param offset Longitude offset to add.
+ * @return new Transformation.
+ */
+TransformationNNPtr Transformation::createLongitudeRotation(
+    const util::PropertyMap &properties, const crs::CRSNNPtr &sourceCRSIn,
+    const crs::CRSNNPtr &targetCRSIn, const common::Angle &offset) {
+
+    return create(
+        properties, sourceCRSIn, targetCRSIn, nullptr,
+        createMethodMapNameEPSGCode(EPSG_CODE_METHOD_LONGITUDE_ROTATION),
+        VectorOfParameters{
+            createOpParamNameEPSGCode(EPSG_CODE_PARAMETER_LONGITUDE_OFFSET)},
+        VectorOfValues{ParameterValue::create(offset)}, buildAccuracyZero());
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+bool Transformation::isLongitudeRotation() const {
+    return method()->getEPSGCode() == EPSG_CODE_METHOD_LONGITUDE_ROTATION;
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a transformation with method Geographic 2D offsets
+ *
+ * This method is defined as [EPSG:9619]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9619)
+ * *
+ * @param properties See \ref general_properties of the Transformation.
+ * At minimum the name should be defined.
+ * @param sourceCRSIn Source CRS.
+ * @param targetCRSIn Target CRS.
+ * @param offsetLat Latitude offset to add.
+ * @param offsetLon Longitude offset to add.
+ * @param accuracies Vector of positional accuracy (might be empty).
+ * @return new Transformation.
+ */
+TransformationNNPtr Transformation::createGeographic2DOffsets(
+    const util::PropertyMap &properties, const crs::CRSNNPtr &sourceCRSIn,
+    const crs::CRSNNPtr &targetCRSIn, const common::Angle &offsetLat,
+    const common::Angle &offsetLon,
+    const std::vector<metadata::PositionalAccuracyNNPtr> &accuracies) {
+    return create(
+        properties, sourceCRSIn, targetCRSIn, nullptr,
+        createMethodMapNameEPSGCode(EPSG_CODE_METHOD_GEOGRAPHIC2D_OFFSETS),
+        VectorOfParameters{
+            createOpParamNameEPSGCode(EPSG_CODE_PARAMETER_LATITUDE_OFFSET),
+            createOpParamNameEPSGCode(EPSG_CODE_PARAMETER_LONGITUDE_OFFSET)},
+        VectorOfValues{offsetLat, offsetLon}, accuracies);
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a transformation with method Geographic 3D offsets
+ *
+ * This method is defined as [EPSG:9660]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9660)
+ * *
+ * @param properties See \ref general_properties of the Transformation.
+ * At minimum the name should be defined.
+ * @param sourceCRSIn Source CRS.
+ * @param targetCRSIn Target CRS.
+ * @param offsetLat Latitude offset to add.
+ * @param offsetLon Longitude offset to add.
+ * @param offsetHeight Height offset to add.
+ * @param accuracies Vector of positional accuracy (might be empty).
+ * @return new Transformation.
+ */
+TransformationNNPtr Transformation::createGeographic3DOffsets(
+    const util::PropertyMap &properties, const crs::CRSNNPtr &sourceCRSIn,
+    const crs::CRSNNPtr &targetCRSIn, const common::Angle &offsetLat,
+    const common::Angle &offsetLon, const common::Length &offsetHeight,
+    const std::vector<metadata::PositionalAccuracyNNPtr> &accuracies) {
+    return create(
+        properties, sourceCRSIn, targetCRSIn, nullptr,
+        createMethodMapNameEPSGCode(EPSG_CODE_METHOD_GEOGRAPHIC3D_OFFSETS),
+        VectorOfParameters{
+            createOpParamNameEPSGCode(EPSG_CODE_PARAMETER_LATITUDE_OFFSET),
+            createOpParamNameEPSGCode(EPSG_CODE_PARAMETER_LONGITUDE_OFFSET),
+            createOpParamNameEPSGCode(EPSG_CODE_PARAMETER_VERTICAL_OFFSET)},
+        VectorOfValues{offsetLat, offsetLon, offsetHeight}, accuracies);
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a transformation with method Geographic 2D with
+ * height
+ * offsets
+ *
+ * This method is defined as [EPSG:9618]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9618)
+ * *
+ * @param properties See \ref general_properties of the Transformation.
+ * At minimum the name should be defined.
+ * @param sourceCRSIn Source CRS.
+ * @param targetCRSIn Target CRS.
+ * @param offsetLat Latitude offset to add.
+ * @param offsetLon Longitude offset to add.
+ * @param offsetHeight Geoid undulation to add.
+ * @param accuracies Vector of positional accuracy (might be empty).
+ * @return new Transformation.
+ */
+TransformationNNPtr Transformation::createGeographic2DWithHeightOffsets(
+    const util::PropertyMap &properties, const crs::CRSNNPtr &sourceCRSIn,
+    const crs::CRSNNPtr &targetCRSIn, const common::Angle &offsetLat,
+    const common::Angle &offsetLon, const common::Length &offsetHeight,
+    const std::vector<metadata::PositionalAccuracyNNPtr> &accuracies) {
+    return create(
+        properties, sourceCRSIn, targetCRSIn, nullptr,
+        createMethodMapNameEPSGCode(
+            EPSG_CODE_METHOD_GEOGRAPHIC2D_WITH_HEIGHT_OFFSETS),
+        VectorOfParameters{
+            createOpParamNameEPSGCode(EPSG_CODE_PARAMETER_LATITUDE_OFFSET),
+            createOpParamNameEPSGCode(EPSG_CODE_PARAMETER_LONGITUDE_OFFSET),
+            createOpParamNameEPSGCode(EPSG_CODE_PARAMETER_GEOID_UNDULATION)},
+        VectorOfValues{offsetLat, offsetLon, offsetHeight}, accuracies);
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a transformation with method Vertical Offset.
+ *
+ * This method is defined as [EPSG:9616]
+ * (https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::9616)
+ * *
+ * @param properties See \ref general_properties of the Transformation.
+ * At minimum the name should be defined.
+ * @param sourceCRSIn Source CRS.
+ * @param targetCRSIn Target CRS.
+ * @param offsetHeight Geoid undulation to add.
+ * @param accuracies Vector of positional accuracy (might be empty).
+ * @return new Transformation.
+ */
+TransformationNNPtr Transformation::createVerticalOffset(
+    const util::PropertyMap &properties, const crs::CRSNNPtr &sourceCRSIn,
+    const crs::CRSNNPtr &targetCRSIn, const common::Length &offsetHeight,
+    const std::vector<metadata::PositionalAccuracyNNPtr> &accuracies) {
+    return create(properties, sourceCRSIn, targetCRSIn, nullptr,
+                  createMethodMapNameEPSGCode(EPSG_CODE_METHOD_VERTICAL_OFFSET),
+                  VectorOfParameters{createOpParamNameEPSGCode(
+                      EPSG_CODE_PARAMETER_VERTICAL_OFFSET)},
+                  VectorOfValues{offsetHeight}, accuracies);
+}
+
+// ---------------------------------------------------------------------------
+
+static const char *getCRSQualifierStr(const crs::CRSPtr &crs) {
+    auto geod = dynamic_cast<crs::GeodeticCRS *>(crs.get());
+    if (geod) {
+        if (geod->isGeocentric()) {
+            return " (geocentric)";
+        }
+        auto geog = dynamic_cast<crs::GeographicCRS *>(geod);
+        if (geog) {
+            if (geog->coordinateSystem()->axisList().size() == 2) {
+                return " (geog2D)";
+            } else {
+                return " (geog3D)";
+            }
+        }
+    }
+    return "";
+}
+
+// ---------------------------------------------------------------------------
+
+static std::string buildOpName(const char *opType, const crs::CRSPtr &source,
+                               const crs::CRSPtr &target) {
+    std::string res(opType);
+    const auto &srcName = source->nameStr();
+    const auto &targetName = target->nameStr();
+    const char *srcQualifier = "";
+    const char *targetQualifier = "";
+    if (srcName == targetName) {
+        srcQualifier = getCRSQualifierStr(source);
+        targetQualifier = getCRSQualifierStr(target);
+        if (strcmp(srcQualifier, targetQualifier) == 0) {
+            srcQualifier = "";
+            targetQualifier = "";
+        }
+    }
+    res += " from ";
+    res += srcName;
+    res += srcQualifier;
+    res += " to ";
+    res += targetName;
+    res += targetQualifier;
+    return res;
+}
+
+// ---------------------------------------------------------------------------
+
+static util::PropertyMap
+createPropertiesForInverse(const CoordinateOperation *op, bool derivedFrom,
+                           bool approximateInversion) {
+    assert(op);
+    util::PropertyMap map;
+
+    // The domain(s) are unchanged by the inverse operation
+    addDomains(map, op);
+
+    const std::string &forwardName = op->nameStr();
+
+    // Forge a name for the inverse, either from the forward name, or
+    // from the source and target CRS names
+    const char *opType;
+    if (starts_with(forwardName, NULL_GEOCENTRIC_TRANSLATION)) {
+        opType = NULL_GEOCENTRIC_TRANSLATION;
+    } else if (starts_with(forwardName, NULL_GEOGRAPHIC_OFFSET)) {
+        opType = NULL_GEOGRAPHIC_OFFSET;
+    } else if (dynamic_cast<const Transformation *>(op) ||
+               starts_with(forwardName, "Transformation from ")) {
+        opType = "Transformation";
+    } else if (dynamic_cast<const Conversion *>(op)) {
+        opType = "Conversion";
+    } else {
+        opType = "Operation";
+    }
+
+    auto sourceCRS = op->sourceCRS();
+    auto targetCRS = op->targetCRS();
+    std::string name;
+    if (!forwardName.empty()) {
+        if (starts_with(forwardName, INVERSE_OF)) {
+            name = forwardName.substr(INVERSE_OF.size());
+        } else if (!sourceCRS || !targetCRS ||
+                   forwardName != buildOpName(opType, sourceCRS, targetCRS)) {
+            name = INVERSE_OF + forwardName;
+        }
+    }
+    if (name.empty() && sourceCRS && targetCRS) {
+        name = buildOpName(opType, targetCRS, sourceCRS);
+    }
+    if (approximateInversion) {
+        name += " (approx. inversion)";
+    }
+
+    if (!name.empty()) {
+        map.set(common::IdentifiedObject::NAME_KEY, name);
+    }
+
+    addModifiedIdentifier(map, op, true, derivedFrom);
+
+    return map;
+}
+
+// ---------------------------------------------------------------------------
+
+static bool isTimeDependent(const std::string &methodName) {
+    return ci_find(methodName, "Time dependent") != std::string::npos ||
+           ci_find(methodName, "Time-dependent") != std::string::npos;
+}
+
+// ---------------------------------------------------------------------------
+
+// to avoid -0...
+static double negate(double val) {
+    if (val != 0) {
+        return -val;
+    }
+    return 0.0;
+}
+
+// ---------------------------------------------------------------------------
+
+static CoordinateOperationPtr
+createApproximateInverseIfPossible(const Transformation *op) {
+    bool sevenParamsTransform = false;
+    bool fifteenParamsTransform = false;
+    const auto &method = op->method();
+    const auto &methodName = method->nameStr();
+    const int methodEPSGCode = method->getEPSGCode();
+    const auto paramCount = op->parameterValues().size();
+    const bool isPositionVector =
+        ci_find(methodName, "Position Vector") != std::string::npos;
+    const bool isCoordinateFrame =
+        ci_find(methodName, "Coordinate Frame") != std::string::npos;
+
+    // See end of "2.4.3.3 Helmert 7-parameter transformations"
+    // in EPSG 7-2 guidance
+    // For practical purposes, the inverse of 7- or 15-parameters Helmert
+    // can be obtained by using the forward method with all parameters
+    // negated
+    // (except reference epoch!)
+    // So for WKT export use that. But for PROJ string, we use the +inv flag
+    // so as to get "perfect" round-tripability.
+    if ((paramCount == 7 && isCoordinateFrame &&
+         !isTimeDependent(methodName)) ||
+        methodEPSGCode == EPSG_CODE_METHOD_COORDINATE_FRAME_GEOCENTRIC ||
+        methodEPSGCode == EPSG_CODE_METHOD_COORDINATE_FRAME_GEOGRAPHIC_2D ||
+        methodEPSGCode == EPSG_CODE_METHOD_COORDINATE_FRAME_GEOGRAPHIC_3D) {
+        sevenParamsTransform = true;
+    } else if (
+        (paramCount == 15 && isCoordinateFrame &&
+         isTimeDependent(methodName)) ||
+        methodEPSGCode ==
+            EPSG_CODE_METHOD_TIME_DEPENDENT_COORDINATE_FRAME_GEOCENTRIC ||
+        methodEPSGCode ==
+            EPSG_CODE_METHOD_TIME_DEPENDENT_COORDINATE_FRAME_GEOGRAPHIC_2D ||
+        methodEPSGCode ==
+            EPSG_CODE_METHOD_TIME_DEPENDENT_COORDINATE_FRAME_GEOGRAPHIC_3D) {
+        fifteenParamsTransform = true;
+    } else if ((paramCount == 7 && isPositionVector &&
+                !isTimeDependent(methodName)) ||
+               methodEPSGCode == EPSG_CODE_METHOD_POSITION_VECTOR_GEOCENTRIC ||
+               methodEPSGCode ==
+                   EPSG_CODE_METHOD_POSITION_VECTOR_GEOGRAPHIC_2D ||
+               methodEPSGCode ==
+                   EPSG_CODE_METHOD_POSITION_VECTOR_GEOGRAPHIC_3D) {
+        sevenParamsTransform = true;
+    } else if (
+        (paramCount == 15 && isPositionVector && isTimeDependent(methodName)) ||
+        methodEPSGCode ==
+            EPSG_CODE_METHOD_TIME_DEPENDENT_POSITION_VECTOR_GEOCENTRIC ||
+        methodEPSGCode ==
+            EPSG_CODE_METHOD_TIME_DEPENDENT_POSITION_VECTOR_GEOGRAPHIC_2D ||
+        methodEPSGCode ==
+            EPSG_CODE_METHOD_TIME_DEPENDENT_POSITION_VECTOR_GEOGRAPHIC_3D) {
+        fifteenParamsTransform = true;
+    }
+    if (sevenParamsTransform || fifteenParamsTransform) {
+        double neg_x = negate(op->parameterValueNumericAsSI(
+            EPSG_CODE_PARAMETER_X_AXIS_TRANSLATION));
+        double neg_y = negate(op->parameterValueNumericAsSI(
+            EPSG_CODE_PARAMETER_Y_AXIS_TRANSLATION));
+        double neg_z = negate(op->parameterValueNumericAsSI(
+            EPSG_CODE_PARAMETER_Z_AXIS_TRANSLATION));
+        double neg_rx = negate(
+            op->parameterValueNumeric(EPSG_CODE_PARAMETER_X_AXIS_ROTATION,
+                                      common::UnitOfMeasure::ARC_SECOND));
+        double neg_ry = negate(
+            op->parameterValueNumeric(EPSG_CODE_PARAMETER_Y_AXIS_ROTATION,
+                                      common::UnitOfMeasure::ARC_SECOND));
+        double neg_rz = negate(
+            op->parameterValueNumeric(EPSG_CODE_PARAMETER_Z_AXIS_ROTATION,
+                                      common::UnitOfMeasure::ARC_SECOND));
+        double neg_scaleDiff = negate(op->parameterValueNumeric(
+            EPSG_CODE_PARAMETER_SCALE_DIFFERENCE,
+            common::UnitOfMeasure::PARTS_PER_MILLION));
+        auto methodProperties = util::PropertyMap().set(
+            common::IdentifiedObject::NAME_KEY, methodName);
+        int method_epsg_code = method->getEPSGCode();
+        if (method_epsg_code) {
+            methodProperties
+                .set(metadata::Identifier::CODESPACE_KEY,
+                     metadata::Identifier::EPSG)
+                .set(metadata::Identifier::CODE_KEY, method_epsg_code);
+        }
+        if (fifteenParamsTransform) {
+            double neg_rate_x = negate(op->parameterValueNumeric(
+                EPSG_CODE_PARAMETER_RATE_X_AXIS_TRANSLATION,
+                common::UnitOfMeasure::METRE_PER_YEAR));
+            double neg_rate_y = negate(op->parameterValueNumeric(
+                EPSG_CODE_PARAMETER_RATE_Y_AXIS_TRANSLATION,
+                common::UnitOfMeasure::METRE_PER_YEAR));
+            double neg_rate_z = negate(op->parameterValueNumeric(
+                EPSG_CODE_PARAMETER_RATE_Z_AXIS_TRANSLATION,
+                common::UnitOfMeasure::METRE_PER_YEAR));
+            double neg_rate_rx = negate(op->parameterValueNumeric(
+                EPSG_CODE_PARAMETER_RATE_X_AXIS_ROTATION,
+                common::UnitOfMeasure::ARC_SECOND_PER_YEAR));
+            double neg_rate_ry = negate(op->parameterValueNumeric(
+                EPSG_CODE_PARAMETER_RATE_Y_AXIS_ROTATION,
+                common::UnitOfMeasure::ARC_SECOND_PER_YEAR));
+            double neg_rate_rz = negate(op->parameterValueNumeric(
+                EPSG_CODE_PARAMETER_RATE_Z_AXIS_ROTATION,
+                common::UnitOfMeasure::ARC_SECOND_PER_YEAR));
+            double neg_rate_scaleDiff = negate(op->parameterValueNumeric(
+                EPSG_CODE_PARAMETER_RATE_SCALE_DIFFERENCE,
+                common::UnitOfMeasure::PPM_PER_YEAR));
+            double referenceEpochYear =
+                op->parameterValueNumeric(EPSG_CODE_PARAMETER_REFERENCE_EPOCH,
+                                          common::UnitOfMeasure::YEAR);
+            return util::nn_static_pointer_cast<CoordinateOperation>(
+                       createFifteenParamsTransform(
+                           createPropertiesForInverse(op, false, true),
+                           methodProperties, op->targetCRS(), op->sourceCRS(),
+                           neg_x, neg_y, neg_z, neg_rx, neg_ry, neg_rz,
+                           neg_scaleDiff, neg_rate_x, neg_rate_y, neg_rate_z,
+                           neg_rate_rx, neg_rate_ry, neg_rate_rz,
+                           neg_rate_scaleDiff, referenceEpochYear,
+                           op->coordinateOperationAccuracies()))
+                .as_nullable();
+        } else {
+            return util::nn_static_pointer_cast<CoordinateOperation>(
+                       createSevenParamsTransform(
+                           createPropertiesForInverse(op, false, true),
+                           methodProperties, op->targetCRS(), op->sourceCRS(),
+                           neg_x, neg_y, neg_z, neg_rx, neg_ry, neg_rz,
+                           neg_scaleDiff, op->coordinateOperationAccuracies()))
+                .as_nullable();
+        }
+    }
+
+    return nullptr;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+TransformationNNPtr
+Transformation::Private::registerInv(util::BaseObjectNNPtr thisIn,
+                                     TransformationNNPtr invTransform) {
+    invTransform->d->forwardOperation_ =
+        util::nn_dynamic_pointer_cast<Transformation>(thisIn);
+    return invTransform;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+CoordinateOperationNNPtr Transformation::inverse() const {
+    return inverseAsTransformation();
+}
+
+// ---------------------------------------------------------------------------
+
+TransformationNNPtr Transformation::inverseAsTransformation() const {
+
+    if (d->forwardOperation_) {
+        return NN_NO_CHECK(d->forwardOperation_);
+    }
+    const auto &l_method = method();
+    const auto &methodName = l_method->nameStr();
+    const int methodEPSGCode = l_method->getEPSGCode();
+    const auto &l_sourceCRS = sourceCRS();
+    const auto &l_targetCRS = targetCRS();
+
+    // For geocentric translation, the inverse is exactly the negation of
+    // the parameters.
+    if (ci_find(methodName, "Geocentric translations") != std::string::npos ||
+        methodEPSGCode == EPSG_CODE_METHOD_GEOCENTRIC_TRANSLATION_GEOCENTRIC ||
+        methodEPSGCode ==
+            EPSG_CODE_METHOD_GEOCENTRIC_TRANSLATION_GEOGRAPHIC_2D ||
+        methodEPSGCode ==
+            EPSG_CODE_METHOD_GEOCENTRIC_TRANSLATION_GEOGRAPHIC_3D) {
+        double x =
+            parameterValueNumericAsSI(EPSG_CODE_PARAMETER_X_AXIS_TRANSLATION);
+        double y =
+            parameterValueNumericAsSI(EPSG_CODE_PARAMETER_Y_AXIS_TRANSLATION);
+        double z =
+            parameterValueNumericAsSI(EPSG_CODE_PARAMETER_Z_AXIS_TRANSLATION);
+        return d->registerInv(
+            shared_from_this(),
+            createGeocentricTranslations(
+                createPropertiesForInverse(this, false, false), l_targetCRS,
+                l_sourceCRS, negate(x), negate(y), negate(z),
+                coordinateOperationAccuracies()));
+    }
+
+    if (methodEPSGCode == EPSG_CODE_METHOD_MOLODENSKY ||
+        methodEPSGCode == EPSG_CODE_METHOD_ABRIDGED_MOLODENSKY) {
+        double x =
+            parameterValueNumericAsSI(EPSG_CODE_PARAMETER_X_AXIS_TRANSLATION);
+        double y =
+            parameterValueNumericAsSI(EPSG_CODE_PARAMETER_Y_AXIS_TRANSLATION);
+        double z =
+            parameterValueNumericAsSI(EPSG_CODE_PARAMETER_Z_AXIS_TRANSLATION);
+        double da = parameterValueNumericAsSI(
+            EPSG_CODE_PARAMETER_SEMI_MAJOR_AXIS_DIFFERENCE);
+        double df = parameterValueNumericAsSI(
+            EPSG_CODE_PARAMETER_FLATTENING_DIFFERENCE);
+
+        if (methodEPSGCode == EPSG_CODE_METHOD_ABRIDGED_MOLODENSKY) {
+            return d->registerInv(
+                shared_from_this(),
+                createAbridgedMolodensky(
+                    createPropertiesForInverse(this, false, false), l_targetCRS,
+                    l_sourceCRS, negate(x), negate(y), negate(z), negate(da),
+                    negate(df), coordinateOperationAccuracies()));
+        } else {
+            return d->registerInv(
+                shared_from_this(),
+                createMolodensky(createPropertiesForInverse(this, false, false),
+                                 l_targetCRS, l_sourceCRS, negate(x), negate(y),
+                                 negate(z), negate(da), negate(df),
+                                 coordinateOperationAccuracies()));
+        }
+    }
+
+    if (isLongitudeRotation()) {
+        auto offset =
+            parameterValueMeasure(EPSG_CODE_PARAMETER_LONGITUDE_OFFSET);
+        const common::Angle newOffset(negate(offset.value()), offset.unit());
+        return d->registerInv(
+            shared_from_this(),
+            createLongitudeRotation(
+                createPropertiesForInverse(this, false, false), l_targetCRS,
+                l_sourceCRS, newOffset));
+    }
+
+    if (methodEPSGCode == EPSG_CODE_METHOD_GEOGRAPHIC2D_OFFSETS) {
+        auto offsetLat =
+            parameterValueMeasure(EPSG_CODE_PARAMETER_LATITUDE_OFFSET);
+        const common::Angle newOffsetLat(negate(offsetLat.value()),
+                                         offsetLat.unit());
+
+        auto offsetLong =
+            parameterValueMeasure(EPSG_CODE_PARAMETER_LONGITUDE_OFFSET);
+        const common::Angle newOffsetLong(negate(offsetLong.value()),
+                                          offsetLong.unit());
+
+        return d->registerInv(
+            shared_from_this(),
+            createGeographic2DOffsets(
+                createPropertiesForInverse(this, false, false), l_targetCRS,
+                l_sourceCRS, newOffsetLat, newOffsetLong,
+                coordinateOperationAccuracies()));
+    }
+
+    if (methodEPSGCode == EPSG_CODE_METHOD_GEOGRAPHIC3D_OFFSETS) {
+        auto offsetLat =
+            parameterValueMeasure(EPSG_CODE_PARAMETER_LATITUDE_OFFSET);
+        const common::Angle newOffsetLat(negate(offsetLat.value()),
+                                         offsetLat.unit());
+
+        auto offsetLong =
+            parameterValueMeasure(EPSG_CODE_PARAMETER_LONGITUDE_OFFSET);
+        const common::Angle newOffsetLong(negate(offsetLong.value()),
+                                          offsetLong.unit());
+
+        auto offsetHeight =
+            parameterValueMeasure(EPSG_CODE_PARAMETER_VERTICAL_OFFSET);
+        const common::Length newOffsetHeight(negate(offsetHeight.value()),
+                                             offsetHeight.unit());
+
+        return d->registerInv(
+            shared_from_this(),
+            createGeographic3DOffsets(
+                createPropertiesForInverse(this, false, false), l_targetCRS,
+                l_sourceCRS, newOffsetLat, newOffsetLong, newOffsetHeight,
+                coordinateOperationAccuracies()));
+    }
+
+    if (methodEPSGCode == EPSG_CODE_METHOD_GEOGRAPHIC2D_WITH_HEIGHT_OFFSETS) {
+        auto offsetLat =
+            parameterValueMeasure(EPSG_CODE_PARAMETER_LATITUDE_OFFSET);
+        const common::Angle newOffsetLat(negate(offsetLat.value()),
+                                         offsetLat.unit());
+
+        auto offsetLong =
+            parameterValueMeasure(EPSG_CODE_PARAMETER_LONGITUDE_OFFSET);
+        const common::Angle newOffsetLong(negate(offsetLong.value()),
+                                          offsetLong.unit());
+
+        auto offsetHeight =
+            parameterValueMeasure(EPSG_CODE_PARAMETER_GEOID_UNDULATION);
+        const common::Length newOffsetHeight(negate(offsetHeight.value()),
+                                             offsetHeight.unit());
+
+        return d->registerInv(
+            shared_from_this(),
+            createGeographic2DWithHeightOffsets(
+                createPropertiesForInverse(this, false, false), l_targetCRS,
+                l_sourceCRS, newOffsetLat, newOffsetLong, newOffsetHeight,
+                coordinateOperationAccuracies()));
+    }
+
+    if (methodEPSGCode == EPSG_CODE_METHOD_VERTICAL_OFFSET) {
+
+        auto offsetHeight =
+            parameterValueMeasure(EPSG_CODE_PARAMETER_VERTICAL_OFFSET);
+        const common::Length newOffsetHeight(negate(offsetHeight.value()),
+                                             offsetHeight.unit());
+
+        return d->registerInv(
+            shared_from_this(),
+            createVerticalOffset(createPropertiesForInverse(this, false, false),
+                                 l_targetCRS, l_sourceCRS, newOffsetHeight,
+                                 coordinateOperationAccuracies()));
+    }
+
+    return InverseTransformation::create(NN_NO_CHECK(
+        util::nn_dynamic_pointer_cast<Transformation>(shared_from_this())));
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+// ---------------------------------------------------------------------------
+
+InverseTransformation::InverseTransformation(const TransformationNNPtr &forward)
+    : Transformation(
+          forward->targetCRS(), forward->sourceCRS(),
+          forward->interpolationCRS(),
+          OperationMethod::create(createPropertiesForInverse(forward->method()),
+                                  forward->method()->parameters()),
+          forward->parameterValues(), forward->coordinateOperationAccuracies()),
+      InverseCoordinateOperation(forward, true) {
+    setPropertiesFromForward();
+}
+
+// ---------------------------------------------------------------------------
+
+InverseTransformation::~InverseTransformation() = default;
+
+// ---------------------------------------------------------------------------
+
+TransformationNNPtr
+InverseTransformation::create(const TransformationNNPtr &forward) {
+    auto conv = util::nn_make_shared<InverseTransformation>(forward);
+    conv->assignSelf(conv);
+    return conv;
+}
+
+// ---------------------------------------------------------------------------
+
+void InverseTransformation::_exportToWKT(io::WKTFormatter *formatter) const {
+
+    auto approxInverse = createApproximateInverseIfPossible(
+        util::nn_dynamic_pointer_cast<Transformation>(forwardOperation_).get());
+    if (approxInverse) {
+        approxInverse->_exportToWKT(formatter);
+    } else {
+        Transformation::_exportToWKT(formatter);
+    }
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void Transformation::_exportToWKT(io::WKTFormatter *formatter) const {
+    exportTransformationToWKT(formatter);
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+void SingleOperation::exportTransformationToWKT(
+    io::WKTFormatter *formatter) const {
+    const bool isWKT2 = formatter->version() == io::WKTFormatter::Version::WKT2;
+    if (!isWKT2) {
+        throw io::FormattingException(
+            "Transformation can only be exported to WKT2");
+    }
+
+    auto l_sourceCRS = sourceCRS();
+    assert(l_sourceCRS);
+    auto l_targetCRS = targetCRS();
+    assert(l_targetCRS);
+
+    if (formatter->abridgedTransformation()) {
+        formatter->startNode(io::WKTConstants::ABRIDGEDTRANSFORMATION,
+                             !identifiers().empty());
+    } else {
+        formatter->startNode(io::WKTConstants::COORDINATEOPERATION,
+                             !identifiers().empty());
+    }
+
+    formatter->addQuotedString(nameStr());
+
+    if (!formatter->abridgedTransformation()) {
+        formatter->startNode(io::WKTConstants::SOURCECRS, false);
+        l_sourceCRS->_exportToWKT(formatter);
+        formatter->endNode();
+
+        formatter->startNode(io::WKTConstants::TARGETCRS, false);
+        l_targetCRS->_exportToWKT(formatter);
+        formatter->endNode();
+    }
+
+    method()->_exportToWKT(formatter);
+
+    const MethodMapping *mapping =
+        !isWKT2 ? getMapping(method().get()) : nullptr;
+    for (const auto &paramValue : parameterValues()) {
+        paramValue->_exportToWKT(formatter, mapping);
+    }
+
+    if (!formatter->abridgedTransformation()) {
+        if (interpolationCRS()) {
+            formatter->startNode(io::WKTConstants::INTERPOLATIONCRS, false);
+            interpolationCRS()->_exportToWKT(formatter);
+            formatter->endNode();
+        }
+
+        if (!coordinateOperationAccuracies().empty()) {
+            formatter->startNode(io::WKTConstants::OPERATIONACCURACY, false);
+            formatter->add(coordinateOperationAccuracies()[0]->value());
+            formatter->endNode();
+        }
+    }
+
+    ObjectUsage::baseExportToWKT(formatter);
+    formatter->endNode();
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static const std::string nullString;
+
+static const std::string &_getNTv2Filename(const Transformation *op,
+                                           bool allowInverse) {
+
+    const auto &l_method = op->method();
+    if (l_method->getEPSGCode() == EPSG_CODE_METHOD_NTV2 ||
+        (allowInverse &&
+         ci_equal(l_method->nameStr(), INVERSE_OF + EPSG_NAME_METHOD_NTV2))) {
+        const auto &fileParameter = op->parameterValue(
+            EPSG_NAME_PARAMETER_LATITUDE_LONGITUDE_DIFFERENCE_FILE,
+            EPSG_CODE_PARAMETER_LATITUDE_LONGITUDE_DIFFERENCE_FILE);
+        if (fileParameter &&
+            fileParameter->type() == ParameterValue::Type::FILENAME) {
+            return fileParameter->valueFile();
+        }
+    }
+    return nullString;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+//! @cond Doxygen_Suppress
+const std::string &Transformation::getNTv2Filename() const {
+
+    return _getNTv2Filename(this, false);
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static const std::string &_getNTv1Filename(const Transformation *op,
+                                           bool allowInverse) {
+
+    const auto &l_method = op->method();
+    const auto &methodName = l_method->nameStr();
+    if (l_method->getEPSGCode() == EPSG_CODE_METHOD_NTV1 ||
+        (allowInverse &&
+         ci_equal(methodName, INVERSE_OF + EPSG_NAME_METHOD_NTV1))) {
+        const auto &fileParameter = op->parameterValue(
+            EPSG_NAME_PARAMETER_LATITUDE_LONGITUDE_DIFFERENCE_FILE,
+            EPSG_CODE_PARAMETER_LATITUDE_LONGITUDE_DIFFERENCE_FILE);
+        if (fileParameter &&
+            fileParameter->type() == ParameterValue::Type::FILENAME) {
+            return fileParameter->valueFile();
+        }
+    }
+    return nullString;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static const std::string &_getCTABLE2Filename(const Transformation *op,
+                                              bool allowInverse) {
+    const auto &l_method = op->method();
+    const auto &methodName = l_method->nameStr();
+    if (ci_equal(methodName, PROJ_WKT2_NAME_METHOD_CTABLE2) ||
+        (allowInverse &&
+         ci_equal(methodName, INVERSE_OF + PROJ_WKT2_NAME_METHOD_CTABLE2))) {
+        const auto &fileParameter = op->parameterValue(
+            EPSG_NAME_PARAMETER_LATITUDE_LONGITUDE_DIFFERENCE_FILE,
+            EPSG_CODE_PARAMETER_LATITUDE_LONGITUDE_DIFFERENCE_FILE);
+        if (fileParameter &&
+            fileParameter->type() == ParameterValue::Type::FILENAME) {
+            return fileParameter->valueFile();
+        }
+    }
+    return nullString;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static const std::string &
+_getHeightToGeographic3DFilename(const Transformation *op, bool allowInverse) {
+
+    const auto &methodName = op->method()->nameStr();
+
+    if (ci_equal(methodName, PROJ_WKT2_NAME_METHOD_HEIGHT_TO_GEOG3D) ||
+        (allowInverse &&
+         ci_equal(methodName,
+                  INVERSE_OF + PROJ_WKT2_NAME_METHOD_HEIGHT_TO_GEOG3D))) {
+        const auto &fileParameter =
+            op->parameterValue(EPSG_NAME_PARAMETER_GEOID_CORRECTION_FILENAME,
+                               EPSG_CODE_PARAMETER_GEOID_CORRECTION_FILENAME);
+        if (fileParameter &&
+            fileParameter->type() == ParameterValue::Type::FILENAME) {
+            return fileParameter->valueFile();
+        }
+    }
+    return nullString;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+const std::string &Transformation::getHeightToGeographic3DFilename() const {
+
+    return _getHeightToGeographic3DFilename(this, false);
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static bool
+isGeographic3DToGravityRelatedHeight(const OperationMethodNNPtr &method,
+                                     bool allowInverse) {
+    const auto &methodName = method->nameStr();
+    static const char *const methodCodes[] = {
+        "1025", // Geographic3D to GravityRelatedHeight (EGM2008)
+        "1030", // Geographic3D to GravityRelatedHeight (NZgeoid)
+        "1045", // Geographic3D to GravityRelatedHeight (OSGM02-Ire)
+        "1047", // Geographic3D to GravityRelatedHeight (Gravsoft)
+        "1048", // Geographic3D to GravityRelatedHeight (Ausgeoid v2)
+        "1050", // Geographic3D to GravityRelatedHeight (CI)
+        "1059", // Geographic3D to GravityRelatedHeight (PNG)
+        "1060", // Geographic3D to GravityRelatedHeight (CGG2013)
+        "1072", // Geographic3D to GravityRelatedHeight (OSGM15-Ire)
+        "1073", // Geographic3D to GravityRelatedHeight (IGN2009)
+        "9661", // Geographic3D to GravityRelatedHeight (EGM)
+        "9662", // Geographic3D to GravityRelatedHeight (Ausgeoid98)
+        "9663", // Geographic3D to GravityRelatedHeight (OSGM-GB)
+        "9664", // Geographic3D to GravityRelatedHeight (IGN1997)
+        "9665", // Geographic3D to GravityRelatedHeight (US .gtx)
+    };
+
+    if (ci_find(methodName, "Geographic3D to GravityRelatedHeight") == 0) {
+        return true;
+    }
+    if (allowInverse &&
+        ci_find(methodName,
+                INVERSE_OF + "Geographic3D to GravityRelatedHeight") == 0) {
+        return true;
+    }
+
+    for (const auto &code : methodCodes) {
+        for (const auto &idSrc : method->identifiers()) {
+            const auto &srcAuthName = *(idSrc->codeSpace());
+            const auto &srcCode = idSrc->code();
+            if (ci_equal(srcAuthName, "EPSG") && srcCode == code) {
+                return true;
+            }
+            if (allowInverse && ci_equal(srcAuthName, "INVERSE(EPSG)") &&
+                srcCode == code) {
+                return true;
+            }
+        }
+    }
+    return false;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static util::PropertyMap
+createSimilarPropertiesMethod(common::IdentifiedObjectNNPtr obj) {
+    util::PropertyMap map;
+
+    const std::string &forwardName = obj->nameStr();
+    if (!forwardName.empty()) {
+        map.set(common::IdentifiedObject::NAME_KEY, forwardName);
+    }
+
+    {
+        auto ar = util::ArrayOfBaseObject::create();
+        for (const auto &idSrc : obj->identifiers()) {
+            const auto &srcAuthName = *(idSrc->codeSpace());
+            const auto &srcCode = idSrc->code();
+            auto idsProp = util::PropertyMap().set(
+                metadata::Identifier::CODESPACE_KEY, srcAuthName);
+            ar->add(metadata::Identifier::create(srcCode, idsProp));
+        }
+        if (!ar->empty()) {
+            map.set(common::IdentifiedObject::IDENTIFIERS_KEY, ar);
+        }
+    }
+
+    return map;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static util::PropertyMap
+createSimilarPropertiesTransformation(TransformationNNPtr obj) {
+    util::PropertyMap map;
+
+    // The domain(s) are unchanged
+    addDomains(map, obj.get());
+
+    std::string forwardName = obj->nameStr();
+    if (!forwardName.empty()) {
+        map.set(common::IdentifiedObject::NAME_KEY, forwardName);
+    }
+
+    addModifiedIdentifier(map, obj.get(), false, true);
+
+    return map;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static TransformationNNPtr
+createNTv1(const util::PropertyMap &properties,
+           const crs::CRSNNPtr &sourceCRSIn, const crs::CRSNNPtr &targetCRSIn,
+           const std::string &filename,
+           const std::vector<metadata::PositionalAccuracyNNPtr> &accuracies) {
+    return Transformation::create(
+        properties, sourceCRSIn, targetCRSIn, nullptr,
+        createMethodMapNameEPSGCode(EPSG_CODE_METHOD_NTV1),
+        {OperationParameter::create(
+            util::PropertyMap()
+                .set(common::IdentifiedObject::NAME_KEY,
+                     EPSG_NAME_PARAMETER_LATITUDE_LONGITUDE_DIFFERENCE_FILE)
+                .set(metadata::Identifier::CODESPACE_KEY,
+                     metadata::Identifier::EPSG)
+                .set(metadata::Identifier::CODE_KEY,
+                     EPSG_CODE_PARAMETER_LATITUDE_LONGITUDE_DIFFERENCE_FILE))},
+        {ParameterValue::createFilename(filename)}, accuracies);
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return an equivalent transformation to the current one, but using
+ * PROJ alternative grid names.
+ */
+TransformationNNPtr Transformation::substitutePROJAlternativeGridNames(
+    io::DatabaseContextNNPtr databaseContext) const {
+    auto self = NN_NO_CHECK(std::dynamic_pointer_cast<Transformation>(
+        shared_from_this().as_nullable()));
+
+    const auto &l_method = method();
+    const int methodEPSGCode = l_method->getEPSGCode();
+
+    std::string projFilename;
+    std::string projGridFormat;
+    bool inverseDirection = false;
+
+    const auto &NTv1Filename = _getNTv1Filename(this, false);
+    const auto &NTv2Filename = _getNTv2Filename(this, false);
+    std::string lasFilename;
+    if (methodEPSGCode == EPSG_CODE_METHOD_NADCON) {
+        const auto &latitudeFileParameter =
+            parameterValue(EPSG_NAME_PARAMETER_LATITUDE_DIFFERENCE_FILE,
+                           EPSG_CODE_PARAMETER_LATITUDE_DIFFERENCE_FILE);
+        const auto &longitudeFileParameter =
+            parameterValue(EPSG_NAME_PARAMETER_LONGITUDE_DIFFERENCE_FILE,
+                           EPSG_CODE_PARAMETER_LONGITUDE_DIFFERENCE_FILE);
+        if (latitudeFileParameter &&
+            latitudeFileParameter->type() == ParameterValue::Type::FILENAME &&
+            longitudeFileParameter &&
+            longitudeFileParameter->type() == ParameterValue::Type::FILENAME) {
+            lasFilename = latitudeFileParameter->valueFile();
+        }
+    }
+    const auto &horizontalGridName =
+        !NTv1Filename.empty() ? NTv1Filename : !NTv2Filename.empty()
+                                                   ? NTv2Filename
+                                                   : lasFilename;
+
+    if (!horizontalGridName.empty() &&
+        databaseContext->lookForGridAlternative(horizontalGridName,
+                                                projFilename, projGridFormat,
+                                                inverseDirection)) {
+
+        if (horizontalGridName == projFilename) {
+            assert(!inverseDirection);
+            return self;
+        }
+
+        const auto &l_sourceCRS = sourceCRS();
+        const auto &l_targetCRS = targetCRS();
+        const auto &l_accuracies = coordinateOperationAccuracies();
+        if (projGridFormat == "NTv1") {
+            if (inverseDirection) {
+                return createNTv1(createPropertiesForInverse(
+                                      self.as_nullable().get(), true, false),
+                                  l_targetCRS, l_sourceCRS, projFilename,
+                                  l_accuracies)
+                    ->inverseAsTransformation();
+            } else {
+                return createNTv1(createSimilarPropertiesTransformation(self),
+                                  l_sourceCRS, l_targetCRS, projFilename,
+                                  l_accuracies);
+            }
+        } else if (projGridFormat == "NTv2") {
+            if (inverseDirection) {
+                return createNTv2(createPropertiesForInverse(
+                                      self.as_nullable().get(), true, false),
+                                  l_targetCRS, l_sourceCRS, projFilename,
+                                  l_accuracies)
+                    ->inverseAsTransformation();
+            } else {
+                return createNTv2(createSimilarPropertiesTransformation(self),
+                                  l_sourceCRS, l_targetCRS, projFilename,
+                                  l_accuracies);
+            }
+        } else if (projGridFormat == "CTable2") {
+            auto parameters =
+                std::vector<OperationParameterNNPtr>{createOpParamNameEPSGCode(
+                    EPSG_CODE_PARAMETER_LATITUDE_LONGITUDE_DIFFERENCE_FILE)};
+            auto methodProperties =
+                util::PropertyMap().set(common::IdentifiedObject::NAME_KEY,
+                                        PROJ_WKT2_NAME_METHOD_CTABLE2);
+            auto values = std::vector<ParameterValueNNPtr>{
+                ParameterValue::createFilename(projFilename)};
+            if (inverseDirection) {
+                return create(createPropertiesForInverse(
+                                  self.as_nullable().get(), true, false),
+                              l_targetCRS, l_sourceCRS, nullptr,
+                              methodProperties, parameters, values,
+                              l_accuracies)
+                    ->inverseAsTransformation();
+
+            } else {
+                return create(createSimilarPropertiesTransformation(self),
+                              l_sourceCRS, l_targetCRS, nullptr,
+                              methodProperties, parameters, values,
+                              l_accuracies);
+            }
+        }
+    }
+
+    const auto &heightFilename = getHeightToGeographic3DFilename();
+    if (!heightFilename.empty() && !projFilename.empty()) {
+        if (databaseContext->lookForGridAlternative(
+                heightFilename, projFilename, projGridFormat,
+                inverseDirection)) {
+
+            if (heightFilename == projFilename) {
+                assert(!inverseDirection);
+                return self;
+            }
+
+            if (inverseDirection) {
+                return createGravityRelatedHeightToGeographic3D(
+                           createPropertiesForInverse(self.as_nullable().get(),
+                                                      true, false),
+                           targetCRS(), sourceCRS(), projFilename,
+                           coordinateOperationAccuracies())
+                    ->inverseAsTransformation();
+            } else {
+                return createGravityRelatedHeightToGeographic3D(
+                    createSimilarPropertiesTransformation(self), sourceCRS(),
+                    targetCRS(), projFilename, coordinateOperationAccuracies());
+            }
+        }
+    }
+
+    if (isGeographic3DToGravityRelatedHeight(method(), false)) {
+        const auto &fileParameter =
+            parameterValue(EPSG_NAME_PARAMETER_GEOID_CORRECTION_FILENAME,
+                           EPSG_CODE_PARAMETER_GEOID_CORRECTION_FILENAME);
+        if (fileParameter &&
+            fileParameter->type() == ParameterValue::Type::FILENAME) {
+            auto filename = fileParameter->valueFile();
+            if (databaseContext->lookForGridAlternative(
+                    filename, projFilename, projGridFormat, inverseDirection)) {
+
+                if (filename == projFilename) {
+                    assert(!inverseDirection);
+                    return self;
+                }
+
+                auto parameters = std::vector<OperationParameterNNPtr>{
+                    createOpParamNameEPSGCode(
+                        EPSG_CODE_PARAMETER_GEOID_CORRECTION_FILENAME)};
+                if (inverseDirection) {
+                    return create(createPropertiesForInverse(
+                                      self.as_nullable().get(), true, false),
+                                  targetCRS(), sourceCRS(), nullptr,
+                                  createSimilarPropertiesMethod(method()),
+                                  parameters, {ParameterValue::createFilename(
+                                                  projFilename)},
+                                  coordinateOperationAccuracies())
+                        ->inverseAsTransformation();
+                } else {
+                    return create(
+                        createSimilarPropertiesTransformation(self),
+                        sourceCRS(), targetCRS(), nullptr,
+                        createSimilarPropertiesMethod(method()), parameters,
+                        {ParameterValue::createFilename(projFilename)},
+                        coordinateOperationAccuracies());
+                }
+            }
+        }
+    }
+
+    return self;
+}
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+static void ThrowExpectionNotGeodeticGeographic(const char *trfrm_name) {
+    throw io::FormattingException(concat("Can apply ", std::string(trfrm_name),
+                                         " only to GeodeticCRS / "
+                                         "GeographicCRS"));
+}
+
+// ---------------------------------------------------------------------------
+
+static void setupPROJGeodeticSourceCRS(io::PROJStringFormatter *formatter,
+                                       const crs::CRSNNPtr &crs,
+                                       const char *trfrm_name) {
+    auto sourceCRSGeog = dynamic_cast<const crs::GeographicCRS *>(crs.get());
+    if (sourceCRSGeog) {
+        formatter->startInversion();
+        sourceCRSGeog->_exportToPROJString(formatter);
+        formatter->stopInversion();
+
+        formatter->addStep("cart");
+        sourceCRSGeog->ellipsoid()->_exportToPROJString(formatter);
+    } else {
+        auto sourceCRSGeod = dynamic_cast<const crs::GeodeticCRS *>(crs.get());
+        if (!sourceCRSGeod) {
+            ThrowExpectionNotGeodeticGeographic(trfrm_name);
+        }
+        formatter->startInversion();
+        sourceCRSGeod->addGeocentricUnitConversionIntoPROJString(formatter);
+        formatter->stopInversion();
+    }
+}
+// ---------------------------------------------------------------------------
+
+static void setupPROJGeodeticTargetCRS(io::PROJStringFormatter *formatter,
+                                       const crs::CRSNNPtr &crs,
+                                       const char *trfrm_name) {
+    auto targetCRSGeog = dynamic_cast<const crs::GeographicCRS *>(crs.get());
+    if (targetCRSGeog) {
+        formatter->addStep("cart");
+        formatter->setCurrentStepInverted(true);
+        targetCRSGeog->ellipsoid()->_exportToPROJString(formatter);
+
+        targetCRSGeog->_exportToPROJString(formatter);
+    } else {
+        auto targetCRSGeod = dynamic_cast<const crs::GeodeticCRS *>(crs.get());
+        if (!targetCRSGeod) {
+            ThrowExpectionNotGeodeticGeographic(trfrm_name);
+        }
+        targetCRSGeod->addGeocentricUnitConversionIntoPROJString(formatter);
+    }
+}
+
+//! @endcond
+// ---------------------------------------------------------------------------
+
+void Transformation::_exportToPROJString(
+    io::PROJStringFormatter *formatter) const // throw(FormattingException)
+{
+    if (formatter->convention() ==
+        io::PROJStringFormatter::Convention::PROJ_4) {
+        throw io::FormattingException(
+            "Transformation cannot be exported as a PROJ.4 string");
+    }
+
+    formatter->setCoordinateOperationOptimizations(true);
+
+    bool positionVectorConvention = true;
+    bool sevenParamsTransform = false;
+    bool threeParamsTransform = false;
+    bool fifteenParamsTransform = false;
+    const auto &l_method = method();
+    const int methodEPSGCode = l_method->getEPSGCode();
+    const auto &methodName = l_method->nameStr();
+    const auto paramCount = parameterValues().size();
+    const bool l_isTimeDependent = isTimeDependent(methodName);
+    const bool isPositionVector =
+        ci_find(methodName, "Position Vector") != std::string::npos ||
+        ci_find(methodName, "PV") != std::string::npos;
+    const bool isCoordinateFrame =
+        ci_find(methodName, "Coordinate Frame") != std::string::npos ||
+        ci_find(methodName, "CF") != std::string::npos;
+    if ((paramCount == 7 && isCoordinateFrame && !l_isTimeDependent) ||
+        methodEPSGCode == EPSG_CODE_METHOD_COORDINATE_FRAME_GEOCENTRIC ||
+        methodEPSGCode == EPSG_CODE_METHOD_COORDINATE_FRAME_GEOGRAPHIC_2D ||
+        methodEPSGCode == EPSG_CODE_METHOD_COORDINATE_FRAME_GEOGRAPHIC_3D) {
+        positionVectorConvention = false;
+        sevenParamsTransform = true;
+    } else if (
+        (paramCount == 15 && isCoordinateFrame && l_isTimeDependent) ||
+        methodEPSGCode ==
+            EPSG_CODE_METHOD_TIME_DEPENDENT_COORDINATE_FRAME_GEOCENTRIC ||
+        methodEPSGCode ==
+            EPSG_CODE_METHOD_TIME_DEPENDENT_COORDINATE_FRAME_GEOGRAPHIC_2D ||
+        methodEPSGCode ==
+            EPSG_CODE_METHOD_TIME_DEPENDENT_COORDINATE_FRAME_GEOGRAPHIC_3D) {
+        positionVectorConvention = false;
+        fifteenParamsTransform = true;
+    } else if ((paramCount == 7 && isPositionVector && !l_isTimeDependent) ||
+               methodEPSGCode == EPSG_CODE_METHOD_POSITION_VECTOR_GEOCENTRIC ||
+               methodEPSGCode ==
+                   EPSG_CODE_METHOD_POSITION_VECTOR_GEOGRAPHIC_2D ||
+               methodEPSGCode ==
+                   EPSG_CODE_METHOD_POSITION_VECTOR_GEOGRAPHIC_3D) {
+        sevenParamsTransform = true;
+    } else if (
+        (paramCount == 15 && isPositionVector && l_isTimeDependent) ||
+        methodEPSGCode ==
+            EPSG_CODE_METHOD_TIME_DEPENDENT_POSITION_VECTOR_GEOCENTRIC ||
+        methodEPSGCode ==
+            EPSG_CODE_METHOD_TIME_DEPENDENT_POSITION_VECTOR_GEOGRAPHIC_2D ||
+        methodEPSGCode ==
+            EPSG_CODE_METHOD_TIME_DEPENDENT_POSITION_VECTOR_GEOGRAPHIC_3D) {
+        fifteenParamsTransform = true;
+    } else if ((paramCount == 3 &&
+                ci_find(methodName, "Geocentric translations") !=
+                    std::string::npos) ||
+               methodEPSGCode ==
+                   EPSG_CODE_METHOD_GEOCENTRIC_TRANSLATION_GEOCENTRIC ||
+               methodEPSGCode ==
+                   EPSG_CODE_METHOD_GEOCENTRIC_TRANSLATION_GEOGRAPHIC_2D ||
+               methodEPSGCode ==
+                   EPSG_CODE_METHOD_GEOCENTRIC_TRANSLATION_GEOGRAPHIC_3D) {
+        threeParamsTransform = true;
+    }
+    if (threeParamsTransform || sevenParamsTransform ||
+        fifteenParamsTransform) {
+        double x =
+            parameterValueNumericAsSI(EPSG_CODE_PARAMETER_X_AXIS_TRANSLATION);
+        double y =
+            parameterValueNumericAsSI(EPSG_CODE_PARAMETER_Y_AXIS_TRANSLATION);
+        double z =
+            parameterValueNumericAsSI(EPSG_CODE_PARAMETER_Z_AXIS_TRANSLATION);
+
+        setupPROJGeodeticSourceCRS(formatter, sourceCRS(), "Helmert");
+
+        formatter->addStep("helmert");
+        formatter->addParam("x", x);
+        formatter->addParam("y", y);
+        formatter->addParam("z", z);
+        if (sevenParamsTransform || fifteenParamsTransform) {
+            double rx =
+                parameterValueNumeric(EPSG_CODE_PARAMETER_X_AXIS_ROTATION,
+                                      common::UnitOfMeasure::ARC_SECOND);
+            double ry =
+                parameterValueNumeric(EPSG_CODE_PARAMETER_Y_AXIS_ROTATION,
+                                      common::UnitOfMeasure::ARC_SECOND);
+            double rz =
+                parameterValueNumeric(EPSG_CODE_PARAMETER_Z_AXIS_ROTATION,
+                                      common::UnitOfMeasure::ARC_SECOND);
+            double scaleDiff =
+                parameterValueNumeric(EPSG_CODE_PARAMETER_SCALE_DIFFERENCE,
+                                      common::UnitOfMeasure::PARTS_PER_MILLION);
+            formatter->addParam("rx", rx);
+            formatter->addParam("ry", ry);
+            formatter->addParam("rz", rz);
+            formatter->addParam("s", scaleDiff);
+            if (fifteenParamsTransform) {
+                double rate_x = parameterValueNumeric(
+                    EPSG_CODE_PARAMETER_RATE_X_AXIS_TRANSLATION,
+                    common::UnitOfMeasure::METRE_PER_YEAR);
+                double rate_y = parameterValueNumeric(
+                    EPSG_CODE_PARAMETER_RATE_Y_AXIS_TRANSLATION,
+                    common::UnitOfMeasure::METRE_PER_YEAR);
+                double rate_z = parameterValueNumeric(
+                    EPSG_CODE_PARAMETER_RATE_Z_AXIS_TRANSLATION,
+                    common::UnitOfMeasure::METRE_PER_YEAR);
+                double rate_rx = parameterValueNumeric(
+                    EPSG_CODE_PARAMETER_RATE_X_AXIS_ROTATION,
+                    common::UnitOfMeasure::ARC_SECOND_PER_YEAR);
+                double rate_ry = parameterValueNumeric(
+                    EPSG_CODE_PARAMETER_RATE_Y_AXIS_ROTATION,
+                    common::UnitOfMeasure::ARC_SECOND_PER_YEAR);
+                double rate_rz = parameterValueNumeric(
+                    EPSG_CODE_PARAMETER_RATE_Z_AXIS_ROTATION,
+                    common::UnitOfMeasure::ARC_SECOND_PER_YEAR);
+                double rate_scaleDiff = parameterValueNumeric(
+                    EPSG_CODE_PARAMETER_RATE_SCALE_DIFFERENCE,
+                    common::UnitOfMeasure::PPM_PER_YEAR);
+                double referenceEpochYear =
+                    parameterValueNumeric(EPSG_CODE_PARAMETER_REFERENCE_EPOCH,
+                                          common::UnitOfMeasure::YEAR);
+                formatter->addParam("dx", rate_x);
+                formatter->addParam("dy", rate_y);
+                formatter->addParam("dz", rate_z);
+                formatter->addParam("drx", rate_rx);
+                formatter->addParam("dry", rate_ry);
+                formatter->addParam("drz", rate_rz);
+                formatter->addParam("ds", rate_scaleDiff);
+                formatter->addParam("t_epoch", referenceEpochYear);
+            }
+            if (positionVectorConvention) {
+                formatter->addParam("convention", "position_vector");
+            } else {
+                formatter->addParam("convention", "coordinate_frame");
+            }
+        }
+
+        setupPROJGeodeticTargetCRS(formatter, targetCRS(), "Helmert");
+
+        return;
+    }
+
+    if (methodEPSGCode == EPSG_CODE_METHOD_MOLODENSKY_BADEKAS_CF_GEOCENTRIC ||
+        methodEPSGCode == EPSG_CODE_METHOD_MOLODENSKY_BADEKAS_PV_GEOCENTRIC ||
+        methodEPSGCode ==
+            EPSG_CODE_METHOD_MOLODENSKY_BADEKAS_CF_GEOGRAPHIC_3D ||
+        methodEPSGCode ==
+            EPSG_CODE_METHOD_MOLODENSKY_BADEKAS_PV_GEOGRAPHIC_3D ||
+        methodEPSGCode ==
+            EPSG_CODE_METHOD_MOLODENSKY_BADEKAS_CF_GEOGRAPHIC_2D ||
+        methodEPSGCode ==
+            EPSG_CODE_METHOD_MOLODENSKY_BADEKAS_PV_GEOGRAPHIC_2D) {
+
+        positionVectorConvention =
+            isPositionVector ||
+            methodEPSGCode ==
+                EPSG_CODE_METHOD_MOLODENSKY_BADEKAS_PV_GEOCENTRIC ||
+            methodEPSGCode ==
+                EPSG_CODE_METHOD_MOLODENSKY_BADEKAS_PV_GEOGRAPHIC_3D ||
+            methodEPSGCode ==
+                EPSG_CODE_METHOD_MOLODENSKY_BADEKAS_PV_GEOGRAPHIC_2D;
+
+        double x =
+            parameterValueNumericAsSI(EPSG_CODE_PARAMETER_X_AXIS_TRANSLATION);
+        double y =
+            parameterValueNumericAsSI(EPSG_CODE_PARAMETER_Y_AXIS_TRANSLATION);
+        double z =
+            parameterValueNumericAsSI(EPSG_CODE_PARAMETER_Z_AXIS_TRANSLATION);
+        double rx = parameterValueNumeric(EPSG_CODE_PARAMETER_X_AXIS_ROTATION,
+                                          common::UnitOfMeasure::ARC_SECOND);
+        double ry = parameterValueNumeric(EPSG_CODE_PARAMETER_Y_AXIS_ROTATION,
+                                          common::UnitOfMeasure::ARC_SECOND);
+        double rz = parameterValueNumeric(EPSG_CODE_PARAMETER_Z_AXIS_ROTATION,
+                                          common::UnitOfMeasure::ARC_SECOND);
+        double scaleDiff =
+            parameterValueNumeric(EPSG_CODE_PARAMETER_SCALE_DIFFERENCE,
+                                  common::UnitOfMeasure::PARTS_PER_MILLION);
+
+        double px = parameterValueNumericAsSI(
+            EPSG_CODE_PARAMETER_ORDINATE_1_EVAL_POINT);
+        double py = parameterValueNumericAsSI(
+            EPSG_CODE_PARAMETER_ORDINATE_2_EVAL_POINT);
+        double pz = parameterValueNumericAsSI(
+            EPSG_CODE_PARAMETER_ORDINATE_3_EVAL_POINT);
+
+        setupPROJGeodeticSourceCRS(formatter, sourceCRS(),
+                                   "Molodensky-Badekas");
+
+        formatter->addStep("molobadekas");
+        formatter->addParam("x", x);
+        formatter->addParam("y", y);
+        formatter->addParam("z", z);
+        formatter->addParam("rx", rx);
+        formatter->addParam("ry", ry);
+        formatter->addParam("rz", rz);
+        formatter->addParam("s", scaleDiff);
+        formatter->addParam("px", px);
+        formatter->addParam("py", py);
+        formatter->addParam("pz", pz);
+        if (positionVectorConvention) {
+            formatter->addParam("convention", "position_vector");
+        } else {
+            formatter->addParam("convention", "coordinate_frame");
+        }
+
+        setupPROJGeodeticTargetCRS(formatter, targetCRS(),
+                                   "Molodensky-Badekas");
+
+        return;
+    }
+
+    if (methodEPSGCode == EPSG_CODE_METHOD_MOLODENSKY ||
+        methodEPSGCode == EPSG_CODE_METHOD_ABRIDGED_MOLODENSKY) {
+        double x =
+            parameterValueNumericAsSI(EPSG_CODE_PARAMETER_X_AXIS_TRANSLATION);
+        double y =
+            parameterValueNumericAsSI(EPSG_CODE_PARAMETER_Y_AXIS_TRANSLATION);
+        double z =
+            parameterValueNumericAsSI(EPSG_CODE_PARAMETER_Z_AXIS_TRANSLATION);
+        double da = parameterValueNumericAsSI(
+            EPSG_CODE_PARAMETER_SEMI_MAJOR_AXIS_DIFFERENCE);
+        double df = parameterValueNumericAsSI(
+            EPSG_CODE_PARAMETER_FLATTENING_DIFFERENCE);
+
+        auto sourceCRSGeog =
+            dynamic_cast<const crs::GeographicCRS *>(sourceCRS().get());
+        if (!sourceCRSGeog) {
+            throw io::FormattingException(
+                "Can apply Molodensky only to GeographicCRS");
+        }
+
+        auto targetCRSGeog =
+            dynamic_cast<const crs::GeographicCRS *>(targetCRS().get());
+        if (!targetCRSGeog) {
+            throw io::FormattingException(
+                "Can apply Molodensky only to GeographicCRS");
+        }
+
+        formatter->startInversion();
+        sourceCRSGeog->_exportToPROJString(formatter);
+        formatter->stopInversion();
+
+        formatter->addStep("molodensky");
+        sourceCRSGeog->ellipsoid()->_exportToPROJString(formatter);
+        formatter->addParam("dx", x);
+        formatter->addParam("dy", y);
+        formatter->addParam("dz", z);
+        formatter->addParam("da", da);
+        formatter->addParam("df", df);
+
+        if (ci_find(methodName, "Abridged") != std::string::npos ||
+            methodEPSGCode == EPSG_CODE_METHOD_ABRIDGED_MOLODENSKY) {
+            formatter->addParam("abridged");
+        }
+
+        targetCRSGeog->_exportToPROJString(formatter);
+
+        return;
+    }
+
+    if (methodEPSGCode == EPSG_CODE_METHOD_GEOGRAPHIC2D_OFFSETS) {
+        double offsetLat =
+            parameterValueNumeric(EPSG_CODE_PARAMETER_LATITUDE_OFFSET,
+                                  common::UnitOfMeasure::ARC_SECOND);
+        double offsetLong =
+            parameterValueNumeric(EPSG_CODE_PARAMETER_LONGITUDE_OFFSET,
+                                  common::UnitOfMeasure::ARC_SECOND);
+
+        auto sourceCRSGeog =
+            dynamic_cast<const crs::GeographicCRS *>(sourceCRS().get());
+        if (!sourceCRSGeog) {
+            throw io::FormattingException(
+                "Can apply Geographic 2D offsets only to GeographicCRS");
+        }
+
+        auto targetCRSGeog =
+            dynamic_cast<const crs::GeographicCRS *>(targetCRS().get());
+        if (!targetCRSGeog) {
+            throw io::FormattingException(
+                "Can apply Geographic 2D offsets only to GeographicCRS");
+        }
+
+        formatter->startInversion();
+        sourceCRSGeog->addAngularUnitConvertAndAxisSwap(formatter);
+        formatter->stopInversion();
+
+        if (offsetLat != 0.0 || offsetLong != 0.0) {
+            formatter->addStep("geogoffset");
+            formatter->addParam("dlat", offsetLat);
+            formatter->addParam("dlon", offsetLong);
+        }
+
+        targetCRSGeog->addAngularUnitConvertAndAxisSwap(formatter);
+
+        return;
+    }
+
+    if (methodEPSGCode == EPSG_CODE_METHOD_GEOGRAPHIC3D_OFFSETS) {
+        double offsetLat =
+            parameterValueNumeric(EPSG_CODE_PARAMETER_LATITUDE_OFFSET,
+                                  common::UnitOfMeasure::ARC_SECOND);
+        double offsetLong =
+            parameterValueNumeric(EPSG_CODE_PARAMETER_LONGITUDE_OFFSET,
+                                  common::UnitOfMeasure::ARC_SECOND);
+        double offsetHeight =
+            parameterValueNumericAsSI(EPSG_CODE_PARAMETER_VERTICAL_OFFSET);
+
+        auto sourceCRSGeog =
+            dynamic_cast<const crs::GeographicCRS *>(sourceCRS().get());
+        if (!sourceCRSGeog) {
+            throw io::FormattingException(
+                "Can apply Geographic 3D offsets only to GeographicCRS");
+        }
+
+        auto targetCRSGeog =
+            dynamic_cast<const crs::GeographicCRS *>(targetCRS().get());
+        if (!targetCRSGeog) {
+            throw io::FormattingException(
+                "Can apply Geographic 3D offsets only to GeographicCRS");
+        }
+
+        formatter->startInversion();
+        sourceCRSGeog->addAngularUnitConvertAndAxisSwap(formatter);
+        formatter->stopInversion();
+
+        if (offsetLat != 0.0 || offsetLong != 0.0 || offsetHeight != 0.0) {
+            formatter->addStep("geogoffset");
+            formatter->addParam("dlat", offsetLat);
+            formatter->addParam("dlon", offsetLong);
+            formatter->addParam("dh", offsetHeight);
+        }
+
+        targetCRSGeog->addAngularUnitConvertAndAxisSwap(formatter);
+
+        return;
+    }
+
+    if (methodEPSGCode == EPSG_CODE_METHOD_GEOGRAPHIC2D_WITH_HEIGHT_OFFSETS) {
+        double offsetLat =
+            parameterValueNumeric(EPSG_CODE_PARAMETER_LATITUDE_OFFSET,
+                                  common::UnitOfMeasure::ARC_SECOND);
+        double offsetLong =
+            parameterValueNumeric(EPSG_CODE_PARAMETER_LONGITUDE_OFFSET,
+                                  common::UnitOfMeasure::ARC_SECOND);
+        double offsetHeight =
+            parameterValueNumericAsSI(EPSG_CODE_PARAMETER_GEOID_UNDULATION);
+
+        auto sourceCRSGeog =
+            dynamic_cast<const crs::GeographicCRS *>(sourceCRS().get());
+        if (!sourceCRSGeog) {
+            auto sourceCRSCompound =
+                dynamic_cast<const crs::CompoundCRS *>(sourceCRS().get());
+            if (sourceCRSCompound) {
+                sourceCRSGeog = sourceCRSCompound->extractGeographicCRS().get();
+            }
+            if (!sourceCRSGeog) {
+                throw io::FormattingException("Can apply Geographic 2D with "
+                                              "height offsets only to "
+                                              "GeographicCRS / CompoundCRS");
+            }
+        }
+
+        auto targetCRSGeog =
+            dynamic_cast<const crs::GeographicCRS *>(targetCRS().get());
+        if (!targetCRSGeog) {
+            auto targetCRSCompound =
+                dynamic_cast<const crs::CompoundCRS *>(targetCRS().get());
+            if (targetCRSCompound) {
+                targetCRSGeog = targetCRSCompound->extractGeographicCRS().get();
+            }
+            if (!targetCRSGeog) {
+                throw io::FormattingException("Can apply Geographic 2D with "
+                                              "height offsets only to "
+                                              "GeographicCRS / CompoundCRS");
+            }
+        }
+
+        formatter->startInversion();
+        sourceCRSGeog->addAngularUnitConvertAndAxisSwap(formatter);
+        formatter->stopInversion();
+
+        if (offsetLat != 0.0 || offsetLong != 0.0 || offsetHeight != 0.0) {
+            formatter->addStep("geogoffset");
+            formatter->addParam("dlat", offsetLat);
+            formatter->addParam("dlon", offsetLong);
+            formatter->addParam("dh", offsetHeight);
+        }
+
+        targetCRSGeog->addAngularUnitConvertAndAxisSwap(formatter);
+
+        return;
+    }
+
+    if (methodEPSGCode == EPSG_CODE_METHOD_VERTICAL_OFFSET) {
+
+        auto sourceCRSVert =
+            dynamic_cast<const crs::VerticalCRS *>(sourceCRS().get());
+        if (!sourceCRSVert) {
+            throw io::FormattingException(
+                "Can apply Vertical offset only to VerticalCRS");
+        }
+
+        auto targetCRSVert =
+            dynamic_cast<const crs::VerticalCRS *>(targetCRS().get());
+        if (!targetCRSVert) {
+            throw io::FormattingException(
+                "Can apply Vertical offset only to VerticalCRS");
+        }
+
+        auto offsetHeight =
+            parameterValueNumericAsSI(EPSG_CODE_PARAMETER_VERTICAL_OFFSET);
+
+        formatter->startInversion();
+        sourceCRSVert->addLinearUnitConvert(formatter);
+        formatter->stopInversion();
+
+        formatter->addStep("geogoffset");
+        formatter->addParam("dh", offsetHeight);
+
+        targetCRSVert->addLinearUnitConvert(formatter);
+
+        return;
+    }
+
+    // Substitute grid names with PROJ friendly names.
+    if (formatter->databaseContext()) {
+        auto alternate = substitutePROJAlternativeGridNames(
+            NN_NO_CHECK(formatter->databaseContext()));
+        auto self = NN_NO_CHECK(std::dynamic_pointer_cast<Transformation>(
+            shared_from_this().as_nullable()));
+
+        if (alternate != self) {
+            alternate->_exportToPROJString(formatter);
+            return;
+        }
+    }
+
+    const bool isMethodInverseOf = starts_with(methodName, INVERSE_OF);
+
+    const auto &NTv1Filename = _getNTv1Filename(this, true);
+    const auto &NTv2Filename = _getNTv2Filename(this, true);
+    const auto &CTABLE2Filename = _getCTABLE2Filename(this, true);
+    const auto &hGridShiftFilename =
+        !NTv1Filename.empty() ? NTv1Filename : !NTv2Filename.empty()
+                                                   ? NTv2Filename
+                                                   : CTABLE2Filename;
+    if (!hGridShiftFilename.empty()) {
+        auto sourceCRSGeog =
+            dynamic_cast<const crs::GeographicCRS *>(sourceCRS().get());
+        if (!sourceCRSGeog) {
+            throw io::FormattingException(
+                concat("Can apply ", methodName, " only to GeographicCRS"));
+        }
+
+        auto targetCRSGeog =
+            dynamic_cast<const crs::GeographicCRS *>(targetCRS().get());
+        if (!targetCRSGeog) {
+            throw io::FormattingException(
+                concat("Can apply ", methodName, " only to GeographicCRS"));
+        }
+
+        formatter->startInversion();
+        sourceCRSGeog->addAngularUnitConvertAndAxisSwap(formatter);
+        formatter->stopInversion();
+
+        if (isMethodInverseOf) {
+            formatter->startInversion();
+        }
+        formatter->addStep("hgridshift");
+        formatter->addParam("grids", hGridShiftFilename);
+        if (isMethodInverseOf) {
+            formatter->stopInversion();
+        }
+
+        targetCRSGeog->addAngularUnitConvertAndAxisSwap(formatter);
+
+        return;
+    }
+
+    const auto &heightFilename = _getHeightToGeographic3DFilename(this, true);
+    if (!heightFilename.empty()) {
+        if (isMethodInverseOf) {
+            formatter->startInversion();
+        }
+        formatter->addStep("vgridshift");
+        formatter->addParam("grids", heightFilename);
+        if (isMethodInverseOf) {
+            formatter->stopInversion();
+        }
+        return;
+    }
+
+    if (isGeographic3DToGravityRelatedHeight(method(), true)) {
+        auto fileParameter =
+            parameterValue(EPSG_NAME_PARAMETER_GEOID_CORRECTION_FILENAME,
+                           EPSG_CODE_PARAMETER_GEOID_CORRECTION_FILENAME);
+        if (fileParameter &&
+            fileParameter->type() == ParameterValue::Type::FILENAME) {
+            auto filename = fileParameter->valueFile();
+            if (isMethodInverseOf) {
+                formatter->startInversion();
+            }
+            formatter->addStep("vgridshift");
+            formatter->addParam("grids", filename);
+            if (isMethodInverseOf) {
+                formatter->stopInversion();
+            }
+            return;
+        }
+    }
+
+    if (methodEPSGCode == EPSG_CODE_METHOD_VERTCON) {
+        auto fileParameter =
+            parameterValue(EPSG_NAME_PARAMETER_VERTICAL_OFFSET_FILE,
+                           EPSG_CODE_PARAMETER_VERTICAL_OFFSET_FILE);
+        if (fileParameter &&
+            fileParameter->type() == ParameterValue::Type::FILENAME) {
+            formatter->addStep("vgridshift");
+            // The vertcon grids go from NGVD 29 to NAVD 88, with units
+            // in millimeter (see
+            // https://github.com/OSGeo/proj.4/issues/1071)
+            formatter->addParam("grids", fileParameter->valueFile());
+            formatter->addParam("multiplier", 0.001);
+            return;
+        }
+    }
+
+    if (isLongitudeRotation()) {
+        double offsetDeg =
+            parameterValueNumeric(EPSG_CODE_PARAMETER_LONGITUDE_OFFSET,
+                                  common::UnitOfMeasure::DEGREE);
+
+        auto sourceCRSGeog =
+            dynamic_cast<const crs::GeographicCRS *>(sourceCRS().get());
+        if (!sourceCRSGeog) {
+            throw io::FormattingException(
+                concat("Can apply ", methodName, " only to GeographicCRS"));
+        }
+
+        auto targetCRSGeog =
+            dynamic_cast<const crs::GeographicCRS *>(targetCRS().get());
+        if (!targetCRSGeog) {
+            throw io::FormattingException(
+                concat("Can apply ", methodName + " only to GeographicCRS"));
+        }
+
+        if (!sourceCRSGeog->ellipsoid()->_isEquivalentTo(
+                targetCRSGeog->ellipsoid().get())) {
+            // This is arguable if we should check this...
+            throw io::FormattingException("Can apply Longitude rotation "
+                                          "only to SRS with same "
+                                          "ellipsoid");
+        }
+
+        formatter->startInversion();
+        sourceCRSGeog->addAngularUnitConvertAndAxisSwap(formatter);
+        formatter->stopInversion();
+
+        bool done = false;
+        if (offsetDeg != 0.0) {
+            // Optimization: as we are doing nominally a +step=inv,
+            // if the negation of the offset value is a well-known name,
+            // then use forward case with this name.
+            auto projPMName = datum::PrimeMeridian::getPROJStringWellKnownName(
+                common::Angle(-offsetDeg));
+            if (!projPMName.empty()) {
+                done = true;
+                formatter->addStep("longlat");
+                sourceCRSGeog->ellipsoid()->_exportToPROJString(formatter);
+                formatter->addParam("pm", projPMName);
+            }
+        }
+        if (!done) {
+            // To actually add the offset, we must use the reverse longlat
+            // operation.
+            formatter->startInversion();
+            formatter->addStep("longlat");
+            sourceCRSGeog->ellipsoid()->_exportToPROJString(formatter);
+            datum::PrimeMeridian::create(util::PropertyMap(),
+                                         common::Angle(offsetDeg))
+                ->_exportToPROJString(formatter);
+            formatter->stopInversion();
+        }
+
+        targetCRSGeog->addAngularUnitConvertAndAxisSwap(formatter);
+
+        return;
+    }
+
+    if (exportToPROJStringGeneric(formatter)) {
+        return;
+    }
+
+    throw io::FormattingException("Unimplemented");
+}
+
+// ---------------------------------------------------------------------------
+
+bool SingleOperation::exportToPROJStringGeneric(
+    io::PROJStringFormatter *formatter) const {
+    const int methodEPSGCode = method()->getEPSGCode();
+
+    if (methodEPSGCode == EPSG_CODE_METHOD_AFFINE_PARAMETRIC_TRANSFORMATION) {
+        const double A0 = parameterValueMeasure(EPSG_CODE_PARAMETER_A0).value();
+        const double A1 = parameterValueMeasure(EPSG_CODE_PARAMETER_A1).value();
+        const double A2 = parameterValueMeasure(EPSG_CODE_PARAMETER_A2).value();
+        const double B0 = parameterValueMeasure(EPSG_CODE_PARAMETER_B0).value();
+        const double B1 = parameterValueMeasure(EPSG_CODE_PARAMETER_B1).value();
+        const double B2 = parameterValueMeasure(EPSG_CODE_PARAMETER_B2).value();
+
+        // Do not mess with axis unit and order for that transformation
+
+        formatter->addStep("affine");
+        formatter->addParam("xoff", A0);
+        formatter->addParam("s11", A1);
+        formatter->addParam("s12", A2);
+        formatter->addParam("yoff", B0);
+        formatter->addParam("s21", B1);
+        formatter->addParam("s22", B2);
+
+        return true;
+    }
+
+    if (isAxisOrderReversal(methodEPSGCode)) {
+        formatter->addStep("axisswap");
+        formatter->addParam("order", "2,1");
+        auto sourceCRSGeog =
+            dynamic_cast<const crs::GeographicCRS *>(sourceCRS().get());
+        auto targetCRSGeog =
+            dynamic_cast<const crs::GeographicCRS *>(targetCRS().get());
+        if (sourceCRSGeog && targetCRSGeog) {
+            const auto &unitSrc =
+                sourceCRSGeog->coordinateSystem()->axisList()[0]->unit();
+            const auto &unitDst =
+                targetCRSGeog->coordinateSystem()->axisList()[0]->unit();
+            if (!unitSrc._isEquivalentTo(
+                    unitDst, util::IComparable::Criterion::EQUIVALENT)) {
+                formatter->addStep("unitconvert");
+                auto projUnit = unitSrc.exportToPROJString();
+                if (projUnit.empty()) {
+                    formatter->addParam("xy_in", unitSrc.conversionToSI());
+                } else {
+                    formatter->addParam("xy_in", projUnit);
+                }
+                projUnit = unitDst.exportToPROJString();
+                if (projUnit.empty()) {
+                    formatter->addParam("xy_out", unitDst.conversionToSI());
+                } else {
+                    formatter->addParam("xy_out", projUnit);
+                }
+            }
+        }
+        return true;
+    }
+
+    if (methodEPSGCode == EPSG_CODE_METHOD_GEOGRAPHIC_GEOCENTRIC) {
+
+        auto sourceCRSGeod =
+            dynamic_cast<const crs::GeodeticCRS *>(sourceCRS().get());
+        auto targetCRSGeod =
+            dynamic_cast<const crs::GeodeticCRS *>(targetCRS().get());
+        if (sourceCRSGeod && targetCRSGeod) {
+            auto sourceCRSGeog =
+                dynamic_cast<const crs::GeographicCRS *>(sourceCRSGeod);
+            auto targetCRSGeog =
+                dynamic_cast<const crs::GeographicCRS *>(targetCRSGeod);
+            bool isSrcGeocentric = sourceCRSGeod->isGeocentric();
+            bool isSrcGeographic = sourceCRSGeog != nullptr;
+            bool isTargetGeocentric = targetCRSGeod->isGeocentric();
+            bool isTargetGeographic = targetCRSGeog != nullptr;
+            if ((isSrcGeocentric && isTargetGeographic) ||
+                (isSrcGeographic && isTargetGeocentric)) {
+
+                formatter->startInversion();
+                sourceCRSGeod->_exportToPROJString(formatter);
+                formatter->stopInversion();
+
+                targetCRSGeod->_exportToPROJString(formatter);
+
+                return true;
+            }
+        }
+
+        throw io::FormattingException("Invalid nature of source and/or "
+                                      "targetCRS for Geographic/Geocentric "
+                                      "conversion");
+    }
+
+    return false;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+PointMotionOperation::~PointMotionOperation() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct ConcatenatedOperation::Private {
+    std::vector<CoordinateOperationNNPtr> operations_{};
+    bool computedName_ = false;
+
+    explicit Private(const std::vector<CoordinateOperationNNPtr> &operationsIn)
+        : operations_(operationsIn) {}
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+ConcatenatedOperation::~ConcatenatedOperation() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+ConcatenatedOperation::ConcatenatedOperation(
+    const std::vector<CoordinateOperationNNPtr> &operationsIn)
+    : CoordinateOperation(), d(internal::make_unique<Private>(operationsIn)) {}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the operation steps of the concatenated operation.
+ *
+ * @return the operation steps.
+ */
+const std::vector<CoordinateOperationNNPtr> &
+ConcatenatedOperation::operations() const {
+    return d->operations_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ConcatenatedOperation
+ *
+ * @param properties See \ref general_properties. At minimum the name should
+ * be
+ * defined.
+ * @param operationsIn Vector of the CoordinateOperation steps.
+ * @param accuracies Vector of positional accuracy (might be empty).
+ * @return new Transformation.
+ * @throws InvalidOperation
+ */
+ConcatenatedOperationNNPtr ConcatenatedOperation::create(
+    const util::PropertyMap &properties,
+    const std::vector<CoordinateOperationNNPtr> &operationsIn,
+    const std::vector<metadata::PositionalAccuracyNNPtr>
+        &accuracies) // throw InvalidOperation
+{
+    if (operationsIn.size() < 2) {
+        throw InvalidOperation(
+            "ConcatenatedOperation must have at least 2 operations");
+    }
+    crs::CRSPtr lastTargetCRS;
+    for (size_t i = 0; i < operationsIn.size(); i++) {
+        auto l_sourceCRS = operationsIn[i]->sourceCRS();
+        auto l_targetCRS = operationsIn[i]->targetCRS();
+        if (l_sourceCRS == nullptr || l_targetCRS == nullptr) {
+            throw InvalidOperation("At least one of the operation lacks a "
+                                   "source and/or target CRS");
+        }
+        if (i >= 1) {
+            const auto &sourceCRSIds = l_sourceCRS->identifiers();
+            const auto &targetCRSIds = lastTargetCRS->identifiers();
+            if (sourceCRSIds.size() == 1 && targetCRSIds.size() == 1 &&
+                sourceCRSIds[0]->code() == targetCRSIds[0]->code() &&
+                *sourceCRSIds[0]->codeSpace() ==
+                    *targetCRSIds[0]->codeSpace()) {
+                // same id --> ok
+            } else if (!l_sourceCRS->_isEquivalentTo(
+                           lastTargetCRS.get(),
+                           util::IComparable::Criterion::EQUIVALENT)) {
+                throw InvalidOperation(
+                    "Inconsistent chaining of CRS in operations");
+            }
+        }
+        lastTargetCRS = l_targetCRS;
+    }
+    auto op = ConcatenatedOperation::nn_make_shared<ConcatenatedOperation>(
+        operationsIn);
+    op->assignSelf(op);
+    op->setProperties(properties);
+    op->setCRSs(NN_NO_CHECK(operationsIn[0]->sourceCRS()),
+                NN_NO_CHECK(operationsIn.back()->targetCRS()), nullptr);
+    op->setAccuracies(accuracies);
+    return op;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static std::string computeConcatenatedName(
+    const std::vector<CoordinateOperationNNPtr> &flattenOps) {
+    std::string name;
+    for (const auto &subOp : flattenOps) {
+        if (!name.empty()) {
+            name += " + ";
+        }
+        const auto &l_name = subOp->nameStr();
+        if (l_name.empty()) {
+            name += "unnamed";
+        } else {
+            name += l_name;
+        }
+    }
+    return name;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ConcatenatedOperation, or return a single
+ * coordinate
+ * operation.
+ *
+ * This computes its accuracy from the sum of its member operations, its
+ * extent
+ *
+ * @param operationsIn Vector of the CoordinateOperation steps.
+ * @param checkExtent Whether we should check the non-emptyness of the
+ * intersection
+ * of the extents of the operations
+ * @throws InvalidOperation
+ */
+CoordinateOperationNNPtr ConcatenatedOperation::createComputeMetadata(
+    const std::vector<CoordinateOperationNNPtr> &operationsIn,
+    bool checkExtent) // throw InvalidOperation
+{
+    util::PropertyMap properties;
+
+    if (operationsIn.size() == 1) {
+        return operationsIn[0];
+    }
+
+    std::vector<CoordinateOperationNNPtr> flattenOps;
+    for (const auto &subOp : operationsIn) {
+        auto subOpConcat =
+            dynamic_cast<const ConcatenatedOperation *>(subOp.get());
+        if (subOpConcat) {
+            auto subOps = subOpConcat->operations();
+            for (const auto &subSubOp : subOps) {
+                flattenOps.emplace_back(subSubOp);
+            }
+        } else {
+            flattenOps.emplace_back(subOp);
+        }
+    }
+    if (flattenOps.size() == 1) {
+        return flattenOps[0];
+    }
+
+    properties.set(common::IdentifiedObject::NAME_KEY,
+                   computeConcatenatedName(flattenOps));
+
+    bool emptyIntersection = false;
+    auto extent = getExtent(flattenOps, false, emptyIntersection);
+    if (checkExtent && emptyIntersection) {
+        std::string msg(
+            "empty intersection of area of validity of concantenated "
+            "operations");
+        throw InvalidOperationEmptyIntersection(msg);
+    }
+    if (extent) {
+        properties.set(common::ObjectUsage::DOMAIN_OF_VALIDITY_KEY,
+                       NN_NO_CHECK(extent));
+    }
+
+    std::vector<metadata::PositionalAccuracyNNPtr> accuracies;
+    const double accuracy = getAccuracy(flattenOps);
+    if (accuracy >= 0.0) {
+        accuracies.emplace_back(
+            metadata::PositionalAccuracy::create(toString(accuracy)));
+    }
+
+    auto op = create(properties, flattenOps, accuracies);
+    op->d->computedName_ = true;
+    return op;
+}
+
+// ---------------------------------------------------------------------------
+
+CoordinateOperationNNPtr ConcatenatedOperation::inverse() const {
+    std::vector<CoordinateOperationNNPtr> inversedOperations;
+    auto l_operations = operations();
+    inversedOperations.reserve(l_operations.size());
+    for (const auto &operation : l_operations) {
+        inversedOperations.emplace_back(operation->inverse());
+    }
+    std::reverse(inversedOperations.begin(), inversedOperations.end());
+
+    auto properties = createPropertiesForInverse(this, false, false);
+    if (d->computedName_) {
+        properties.set(common::IdentifiedObject::NAME_KEY,
+                       computeConcatenatedName(inversedOperations));
+    }
+
+    auto op =
+        create(properties, inversedOperations, coordinateOperationAccuracies());
+    op->d->computedName_ = d->computedName_;
+    return op;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void ConcatenatedOperation::_exportToWKT(io::WKTFormatter *formatter) const {
+    const bool isWKT2 = formatter->version() == io::WKTFormatter::Version::WKT2;
+    if (!isWKT2 || !formatter->use2018Keywords()) {
+        throw io::FormattingException(
+            "Transformation can only be exported to WKT2:2018");
+    }
+
+    formatter->startNode(io::WKTConstants::CONCATENATEDOPERATION,
+                         !identifiers().empty());
+    formatter->addQuotedString(nameStr());
+
+    formatter->startNode(io::WKTConstants::SOURCECRS, false);
+    sourceCRS()->_exportToWKT(formatter);
+    formatter->endNode();
+
+    formatter->startNode(io::WKTConstants::TARGETCRS, false);
+    targetCRS()->_exportToWKT(formatter);
+    formatter->endNode();
+
+    for (const auto &operation : operations()) {
+        formatter->startNode(io::WKTConstants::STEP, false);
+        operation->_exportToWKT(formatter);
+        formatter->endNode();
+    }
+
+    ObjectUsage::baseExportToWKT(formatter);
+    formatter->endNode();
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+void ConcatenatedOperation::_exportToPROJString(
+    io::PROJStringFormatter *formatter) const // throw(FormattingException)
+{
+    for (const auto &operation : operations()) {
+        operation->_exportToPROJString(formatter);
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+bool ConcatenatedOperation::_isEquivalentTo(
+    const util::IComparable *other,
+    util::IComparable::Criterion criterion) const {
+    auto otherCO = dynamic_cast<const ConcatenatedOperation *>(other);
+    if (otherCO == nullptr || !ObjectUsage::_isEquivalentTo(other, criterion)) {
+        return false;
+    }
+    const auto &steps = operations();
+    const auto &otherSteps = otherCO->operations();
+    if (steps.size() != otherSteps.size()) {
+        return false;
+    }
+    for (size_t i = 0; i < steps.size(); i++) {
+        if (!steps[i]->_isEquivalentTo(otherSteps[i].get(), criterion)) {
+            return false;
+        }
+    }
+    return true;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+std::set<GridDescription> ConcatenatedOperation::gridsNeeded(
+    const io::DatabaseContextPtr &databaseContext) const {
+    std::set<GridDescription> res;
+    for (const auto &operation : operations()) {
+        const auto l_gridsNeeded = operation->gridsNeeded(databaseContext);
+        for (const auto &gridDesc : l_gridsNeeded) {
+            res.insert(gridDesc);
+        }
+    }
+    return res;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct CoordinateOperationContext::Private {
+    io::AuthorityFactoryPtr authorityFactory_{};
+    metadata::ExtentPtr extent_{};
+    double accuracy_ = 0.0;
+    SourceTargetCRSExtentUse sourceAndTargetCRSExtentUse_ =
+        CoordinateOperationContext::SourceTargetCRSExtentUse::SMALLEST;
+    SpatialCriterion spatialCriterion_ =
+        CoordinateOperationContext::SpatialCriterion::STRICT_CONTAINMENT;
+    bool usePROJNames_ = true;
+    GridAvailabilityUse gridAvailabilityUse_ =
+        GridAvailabilityUse::USE_FOR_SORTING;
+    bool allowUseIntermediateCRS_ = true;
+    std::vector<std::pair<std::string, std::string>>
+        intermediateCRSAuthCodes_{};
+    bool discardSuperseded_ = true;
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+CoordinateOperationContext::~CoordinateOperationContext() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+CoordinateOperationContext::CoordinateOperationContext()
+    : d(internal::make_unique<Private>()) {}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the authority factory, or null */
+const io::AuthorityFactoryPtr &
+CoordinateOperationContext::getAuthorityFactory() const {
+    return d->authorityFactory_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the desired area of interest, or null */
+const metadata::ExtentPtr &
+CoordinateOperationContext::getAreaOfInterest() const {
+    return d->extent_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Set the desired area of interest, or null */
+void CoordinateOperationContext::setAreaOfInterest(
+    const metadata::ExtentPtr &extent) {
+    d->extent_ = extent;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the desired accuracy (in metre), or 0 */
+double CoordinateOperationContext::getDesiredAccuracy() const {
+    return d->accuracy_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Set the desired accuracy (in metre), or 0 */
+void CoordinateOperationContext::setDesiredAccuracy(double accuracy) {
+    d->accuracy_ = accuracy;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Set how source and target CRS extent should be used
+ * when considering if a transformation can be used (only takes effect if
+ * no area of interest is explicitly defined).
+ *
+ * The default is
+ * CoordinateOperationContext::SourceTargetCRSExtentUse::SMALLEST.
+ */
+void CoordinateOperationContext::setSourceAndTargetCRSExtentUse(
+    SourceTargetCRSExtentUse use) {
+    d->sourceAndTargetCRSExtentUse_ = use;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return how source and target CRS extent should be used
+ * when considering if a transformation can be used (only takes effect if
+ * no area of interest is explicitly defined).
+ *
+ * The default is
+ * CoordinateOperationContext::SourceTargetCRSExtentUse::SMALLEST.
+ */
+CoordinateOperationContext::SourceTargetCRSExtentUse
+CoordinateOperationContext::getSourceAndTargetCRSExtentUse() const {
+    return d->sourceAndTargetCRSExtentUse_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Set the spatial criterion to use when comparing the area of
+ * validity
+ * of coordinate operations with the area of interest / area of validity of
+ * source and target CRS.
+ *
+ * The default is STRICT_CONTAINMENT.
+ */
+void CoordinateOperationContext::setSpatialCriterion(
+    SpatialCriterion criterion) {
+    d->spatialCriterion_ = criterion;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the spatial criterion to use when comparing the area of
+ * validity
+ * of coordinate operations with the area of interest / area of validity of
+ * source and target CRS.
+ *
+ * The default is STRICT_CONTAINMENT.
+ */
+CoordinateOperationContext::SpatialCriterion
+CoordinateOperationContext::getSpatialCriterion() const {
+    return d->spatialCriterion_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Set whether PROJ alternative grid names should be substituted to
+ * the official authority names.
+ *
+ * This only has effect is an authority factory with a non-null database context
+ * has been attached to this context.
+ *
+ * If set to false, it is still possible to
+ * obtain later the substitution by using io::PROJStringFormatter::create()
+ * with a non-null database context.
+ *
+ * The default is true.
+ */
+void CoordinateOperationContext::setUsePROJAlternativeGridNames(
+    bool usePROJNames) {
+    d->usePROJNames_ = usePROJNames;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return whether PROJ alternative grid names should be substituted to
+ * the official authority names.
+ *
+ * The default is true.
+ */
+bool CoordinateOperationContext::getUsePROJAlternativeGridNames() const {
+    return d->usePROJNames_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return whether transformations that are superseded (but not
+ * deprecated)
+ * should be discarded.
+ *
+ * The default is true.
+ */
+bool CoordinateOperationContext::getDiscardSuperseded() const {
+    return d->discardSuperseded_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Set whether transformations that are superseded (but not deprecated)
+ * should be discarded.
+ *
+ * The default is true.
+ */
+void CoordinateOperationContext::setDiscardSuperseded(bool discard) {
+    d->discardSuperseded_ = discard;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Set how grid availability is used.
+ *
+ * The default is USE_FOR_SORTING.
+ */
+void CoordinateOperationContext::setGridAvailabilityUse(
+    GridAvailabilityUse use) {
+    d->gridAvailabilityUse_ = use;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return how grid availability is used.
+ *
+ * The default is USE_FOR_SORTING.
+ */
+CoordinateOperationContext::GridAvailabilityUse
+CoordinateOperationContext::getGridAvailabilityUse() const {
+    return d->gridAvailabilityUse_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Set whether an intermediate pivot CRS can be used for researching
+ * coordinate operations between a source and target CRS.
+ *
+ * Concretely if in the database there is an operation from A to C
+ * (or C to A), and another one from C to B (or B to C), but no direct
+ * operation between A and B, setting this parameter to true, allow
+ * chaining both operations.
+ *
+ * The current implementation is limited to researching one intermediate
+ * step.
+ *
+ * By default, all potential C candidates will be used. setIntermediateCRS()
+ * can be used to restrict them.
+ *
+ * The default is true.
+ */
+void CoordinateOperationContext::setAllowUseIntermediateCRS(bool use) {
+    d->allowUseIntermediateCRS_ = use;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return whether an intermediate pivot CRS can be used for researching
+ * coordinate operations between a source and target CRS.
+ *
+ * Concretely if in the database there is an operation from A to C
+ * (or C to A), and another one from C to B (or B to C), but no direct
+ * operation between A and B, setting this parameter to true, allow
+ * chaining both operations.
+ *
+ * The default is true.
+ */
+bool CoordinateOperationContext::getAllowUseIntermediateCRS() const {
+    return d->allowUseIntermediateCRS_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Restrict the potential pivot CRSs that can be used when trying to
+ * build a coordinate operation between two CRS that have no direct operation.
+ *
+ * @param intermediateCRSAuthCodes a vector of (auth_name, code) that can be
+ * used as potential pivot RS
+ */
+void CoordinateOperationContext::setIntermediateCRS(
+    const std::vector<std::pair<std::string, std::string>>
+        &intermediateCRSAuthCodes) {
+    d->intermediateCRSAuthCodes_ = intermediateCRSAuthCodes;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the potential pivot CRSs that can be used when trying to
+ * build a coordinate operation between two CRS that have no direct operation.
+ *
+ */
+const std::vector<std::pair<std::string, std::string>> &
+CoordinateOperationContext::getIntermediateCRS() const {
+    return d->intermediateCRSAuthCodes_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Creates a context for a coordinate operation.
+ *
+ * If a non null authorityFactory is provided, the resulting context should
+ * not be used simultaneously by more than one thread.
+ *
+ * If authorityFactory->getAuthority() is the empty string, then coordinate
+ * operations from any authority will be searched, with the restrictions set
+ * in the authority_to_authority_preference database table.
+ * If authorityFactory->getAuthority() is set to "any", then coordinate
+ * operations from any authority will be searched
+ * If authorityFactory->getAuthority() is a non-empty string different of "any",
+ * then coordinate operatiosn will be searched only in that authority namespace.
+ *
+ * @param authorityFactory Authority factory, or null if no database lookup
+ * is allowed.
+ * Use io::authorityFactory::create(context, std::string()) to allow all
+ * authorities to be used.
+ * @param extent Area of interest, or null if none is known.
+ * @param accuracy Maximum allowed accuracy in metre, as specified in or
+ * 0 to get best accuracy.
+ * @return a new context.
+ */
+CoordinateOperationContextNNPtr CoordinateOperationContext::create(
+    const io::AuthorityFactoryPtr &authorityFactory,
+    const metadata::ExtentPtr &extent, double accuracy) {
+    auto ctxt = NN_NO_CHECK(
+        CoordinateOperationContext::make_unique<CoordinateOperationContext>());
+    ctxt->d->authorityFactory_ = authorityFactory;
+    ctxt->d->extent_ = extent;
+    ctxt->d->accuracy_ = accuracy;
+    return ctxt;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct CoordinateOperationFactory::Private {
+
+    struct Context {
+        // This is the source CRS and target CRS of the initial
+        // CoordinateOperationFactory::createOperations() public call, not
+        // necessarily the ones of intermediate
+        // CoordinateOperationFactory::Private::createOperations() calls.
+        // This is used to compare transformations area of use against the
+        // area of use of the source & target CRS.
+        const crs::CRSNNPtr &sourceCRS;
+        const crs::CRSNNPtr &targetCRS;
+        const CoordinateOperationContextNNPtr &context;
+        bool inCreateOperationsWithDatumPivotAntiRecursion = false;
+
+        Context(const crs::CRSNNPtr &sourceCRSIn,
+                const crs::CRSNNPtr &targetCRSIn,
+                const CoordinateOperationContextNNPtr &contextIn)
+            : sourceCRS(sourceCRSIn), targetCRS(targetCRSIn),
+              context(contextIn) {}
+    };
+
+    static std::vector<CoordinateOperationNNPtr>
+    createOperations(const crs::CRSNNPtr &sourceCRS,
+                     const crs::CRSNNPtr &targetCRS, Context &context);
+
+  private:
+    static std::vector<CoordinateOperationNNPtr> createOperationsGeogToGeog(
+        std::vector<CoordinateOperationNNPtr> &res,
+        const crs::CRSNNPtr &sourceCRS, const crs::CRSNNPtr &targetCRS,
+        const crs::GeographicCRS *geogSrc, const crs::GeographicCRS *geogDst);
+
+    static void createOperationsWithDatumPivot(
+        std::vector<CoordinateOperationNNPtr> &res,
+        const crs::CRSNNPtr &sourceCRS, const crs::CRSNNPtr &targetCRS,
+        const crs::GeodeticCRS *geodSrc, const crs::GeodeticCRS *geodDst,
+        Context &context);
+
+    static bool
+    hasPerfectAccuracyResult(const std::vector<CoordinateOperationNNPtr> &res,
+                             const Context &context);
+
+    static ConversionNNPtr
+    createGeographicGeocentric(const crs::CRSNNPtr &sourceCRS,
+                               const crs::CRSNNPtr &targetCRS);
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+CoordinateOperationFactory::~CoordinateOperationFactory() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+CoordinateOperationFactory::CoordinateOperationFactory() : d(nullptr) {}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Find a CoordinateOperation from sourceCRS to targetCRS.
+ *
+ * This is a helper of createOperations(), using a coordinate operation
+ * context
+ * with no authority factory (so no catalog searching is done), no desired
+ * accuracy and no area of interest.
+ * This returns the first operation of the result set of createOperations(),
+ * or null if none found.
+ *
+ * @param sourceCRS source CRS.
+ * @param targetCRS source CRS.
+ * @return a CoordinateOperation or nullptr.
+ */
+CoordinateOperationPtr CoordinateOperationFactory::createOperation(
+    const crs::CRSNNPtr &sourceCRS, const crs::CRSNNPtr &targetCRS) const {
+    auto res = createOperations(
+        sourceCRS, targetCRS,
+        CoordinateOperationContext::create(nullptr, nullptr, 0.0));
+    if (!res.empty()) {
+        return res[0];
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+// ---------------------------------------------------------------------------
+
+struct PrecomputedOpCharacteristics {
+    double area_{};
+    double accuracy_{};
+    bool hasGrids_ = false;
+    bool gridsAvailable_ = false;
+    bool gridsKnown_ = false;
+    size_t stepCount_ = 0;
+
+    PrecomputedOpCharacteristics() = default;
+    PrecomputedOpCharacteristics(double area, double accuracy, bool hasGrids,
+                                 bool gridsAvailable, bool gridsKnown,
+                                 size_t stepCount)
+        : area_(area), accuracy_(accuracy), hasGrids_(hasGrids),
+          gridsAvailable_(gridsAvailable), gridsKnown_(gridsKnown),
+          stepCount_(stepCount) {}
+};
+
+// ---------------------------------------------------------------------------
+
+// We could have used a lambda instead of this old-school way, but
+// filterAndSort() is already huge.
+struct SortFunction {
+
+    const std::map<CoordinateOperation *, PrecomputedOpCharacteristics> &map;
+
+    explicit SortFunction(const std::map<CoordinateOperation *,
+                                         PrecomputedOpCharacteristics> &mapIn)
+        : map(mapIn) {}
+
+    // Sorting function
+    // Return true if a < b
+    bool operator()(const CoordinateOperationNNPtr &a,
+                    const CoordinateOperationNNPtr &b) const {
+        auto iterA = map.find(a.get());
+        assert(iterA != map.end());
+        auto iterB = map.find(b.get());
+        assert(iterB != map.end());
+
+        // CAUTION: the order of the comparisons is extremely important
+        // to get the intended result.
+
+        if (iterA->second.hasGrids_ && iterB->second.hasGrids_) {
+            // Operations where grids are all available go before other
+            if (iterA->second.gridsAvailable_ &&
+                !iterB->second.gridsAvailable_) {
+                return true;
+            }
+            if (iterB->second.gridsAvailable_ &&
+                !iterA->second.gridsAvailable_) {
+                return false;
+            }
+        }
+
+        // Operations where grids are all known in our DB go before other
+        if (iterA->second.gridsKnown_ && !iterB->second.gridsKnown_) {
+            return true;
+        }
+        if (iterB->second.gridsKnown_ && !iterA->second.gridsKnown_) {
+            return false;
+        }
+
+        // Operations with known accuracy go before those with unknown accuracy
+        const double accuracyA = iterA->second.accuracy_;
+        const double accuracyB = iterB->second.accuracy_;
+        if (accuracyA >= 0 && accuracyB < 0) {
+            return true;
+        }
+        if (accuracyB >= 0 && accuracyA < 0) {
+            return false;
+        }
+
+        // Operations with larger non-zero area of use go before those with
+        // lower one
+        const double areaA = iterA->second.area_;
+        const double areaB = iterB->second.area_;
+        if (areaA > 0) {
+            if (areaA > areaB) {
+                return true;
+            }
+            if (areaA < areaB) {
+                return false;
+            }
+        } else if (areaB > 0) {
+            return false;
+        }
+
+        // Operations with better accuracy go before those with worse one
+        if (accuracyA >= 0 && accuracyA < accuracyB) {
+            return true;
+        }
+        if (accuracyB >= 0 && accuracyB < accuracyA) {
+            return false;
+        }
+
+        if (accuracyA >= 0 && accuracyA == accuracyB) {
+            // same accuracy ? then prefer operations without grids
+            if (!iterA->second.hasGrids_ && iterB->second.hasGrids_) {
+                return true;
+            }
+            if (iterA->second.hasGrids_ && !iterB->second.hasGrids_) {
+                return false;
+            }
+        } else if (accuracyA < 0 && accuracyB < 0) {
+            // unknown accuracy ? then prefer operations with grids, which
+            // are likely to have best practical accuracy
+            if (iterA->second.hasGrids_ && !iterB->second.hasGrids_) {
+                return true;
+            }
+            if (!iterA->second.hasGrids_ && iterB->second.hasGrids_) {
+                return false;
+            }
+        }
+
+        // The less intermediate steps, the better
+        if (iterA->second.stepCount_ < iterB->second.stepCount_) {
+            return true;
+        }
+        if (iterB->second.stepCount_ < iterA->second.stepCount_) {
+            return false;
+        }
+
+        const auto &a_name = a->nameStr();
+        const auto &b_name = b->nameStr();
+        // The shorter name, the better ?
+        if (a_name.size() < b_name.size()) {
+            return true;
+        }
+        if (b_name.size() < a_name.size()) {
+            return false;
+        }
+
+        // Arbitrary final criterion
+        return a_name < b_name;
+    }
+};
+
+// ---------------------------------------------------------------------------
+
+static size_t getStepCount(const CoordinateOperationNNPtr &op) {
+    auto concat = dynamic_cast<const ConcatenatedOperation *>(op.get());
+    size_t stepCount = 1;
+    if (concat) {
+        stepCount = concat->operations().size();
+    }
+    return stepCount;
+}
+
+// ---------------------------------------------------------------------------
+
+struct FilterResults {
+
+    FilterResults(const std::vector<CoordinateOperationNNPtr> &sourceListIn,
+                  const CoordinateOperationContextNNPtr &contextIn,
+                  const crs::CRSNNPtr &sourceCRSIn,
+                  const crs::CRSNNPtr &targetCRSIn,
+                  bool forceStrictContainmentTest)
+        : sourceList(sourceListIn), context(contextIn), sourceCRS(sourceCRSIn),
+          targetCRS(targetCRSIn), sourceCRSExtent(getExtent(sourceCRS)),
+          targetCRSExtent(getExtent(targetCRS)),
+          areaOfInterest(context->getAreaOfInterest()),
+          desiredAccuracy(context->getDesiredAccuracy()),
+          sourceAndTargetCRSExtentUse(
+              context->getSourceAndTargetCRSExtentUse()) {
+
+        computeAreaOfIntest();
+        filterOut(forceStrictContainmentTest);
+    }
+
+    FilterResults &andSort() {
+        sort();
+
+        // And now that we have a sorted list, we can remove uninteresting
+        // results
+        // ...
+        removeSyntheticNullTransforms();
+        removeUninterestingOps();
+        removeDuplicateOps();
+        removeSyntheticNullTransforms();
+        return *this;
+    }
+
+    // ----------------------------------------------------------------------
+
+    // cppcheck-suppress functionStatic
+    const std::vector<CoordinateOperationNNPtr> &getRes() { return res; }
+
+    // ----------------------------------------------------------------------
+  private:
+    const std::vector<CoordinateOperationNNPtr> &sourceList;
+    const CoordinateOperationContextNNPtr &context;
+    const crs::CRSNNPtr &sourceCRS;
+    const crs::CRSNNPtr &targetCRS;
+    const metadata::ExtentPtr &sourceCRSExtent;
+    const metadata::ExtentPtr &targetCRSExtent;
+    metadata::ExtentPtr areaOfInterest;
+    const double desiredAccuracy = context->getDesiredAccuracy();
+    const CoordinateOperationContext::SourceTargetCRSExtentUse
+        sourceAndTargetCRSExtentUse;
+
+    bool hasOpThatContainsAreaOfInterest = false;
+    std::vector<CoordinateOperationNNPtr> res{};
+
+    // ----------------------------------------------------------------------
+    void computeAreaOfIntest() {
+
+        // Compute an area of interest from the CRS extent if the user did
+        // not specify one
+        if (!areaOfInterest) {
+            if (sourceAndTargetCRSExtentUse ==
+                CoordinateOperationContext::SourceTargetCRSExtentUse::
+                    INTERSECTION) {
+                if (sourceCRSExtent && targetCRSExtent) {
+                    areaOfInterest = sourceCRSExtent->intersection(
+                        NN_NO_CHECK(targetCRSExtent));
+                }
+            } else if (sourceAndTargetCRSExtentUse ==
+                       CoordinateOperationContext::SourceTargetCRSExtentUse::
+                           SMALLEST) {
+                if (sourceCRSExtent && targetCRSExtent) {
+                    if (getPseudoArea(sourceCRSExtent) <
+                        getPseudoArea(targetCRSExtent)) {
+                        areaOfInterest = sourceCRSExtent;
+                    } else {
+                        areaOfInterest = targetCRSExtent;
+                    }
+                } else if (sourceCRSExtent) {
+                    areaOfInterest = sourceCRSExtent;
+                } else {
+                    areaOfInterest = targetCRSExtent;
+                }
+            }
+        }
+    }
+
+    // ---------------------------------------------------------------------------
+
+    void filterOut(bool forceStrictContainmentTest) {
+
+        // Filter out operations that do not match the expected accuracy
+        // and area of use.
+        const auto spatialCriterion =
+            forceStrictContainmentTest
+                ? CoordinateOperationContext::SpatialCriterion::
+                      STRICT_CONTAINMENT
+                : context->getSpatialCriterion();
+        for (const auto &op : sourceList) {
+            if (desiredAccuracy != 0) {
+                const double accuracy = getAccuracy(op);
+                if (accuracy < 0 || accuracy > desiredAccuracy) {
+                    continue;
+                }
+            }
+            if (areaOfInterest) {
+                bool emptyIntersection = false;
+                auto extent = getExtent(op, true, emptyIntersection);
+                if (!extent)
+                    continue;
+                bool extentContains =
+                    extent->contains(NN_NO_CHECK(areaOfInterest));
+                if (extentContains) {
+                    hasOpThatContainsAreaOfInterest = true;
+                }
+                if (spatialCriterion ==
+                        CoordinateOperationContext::SpatialCriterion::
+                            STRICT_CONTAINMENT &&
+                    !extentContains) {
+                    continue;
+                }
+                if (spatialCriterion ==
+                        CoordinateOperationContext::SpatialCriterion::
+                            PARTIAL_INTERSECTION &&
+                    !extent->intersects(NN_NO_CHECK(areaOfInterest))) {
+                    continue;
+                }
+            } else if (sourceAndTargetCRSExtentUse ==
+                       CoordinateOperationContext::SourceTargetCRSExtentUse::
+                           BOTH) {
+                bool emptyIntersection = false;
+                auto extent = getExtent(op, true, emptyIntersection);
+                if (!extent)
+                    continue;
+                bool extentContainsSource =
+                    !sourceCRSExtent ||
+                    extent->contains(NN_NO_CHECK(sourceCRSExtent));
+                bool extentContainsTarget =
+                    !targetCRSExtent ||
+                    extent->contains(NN_NO_CHECK(targetCRSExtent));
+                if (extentContainsSource && extentContainsTarget) {
+                    hasOpThatContainsAreaOfInterest = true;
+                }
+                if (spatialCriterion ==
+                    CoordinateOperationContext::SpatialCriterion::
+                        STRICT_CONTAINMENT) {
+                    if (!extentContainsSource || !extentContainsTarget) {
+                        continue;
+                    }
+                } else if (spatialCriterion ==
+                           CoordinateOperationContext::SpatialCriterion::
+                               PARTIAL_INTERSECTION) {
+                    bool extentIntersectsSource =
+                        !sourceCRSExtent ||
+                        extent->intersects(NN_NO_CHECK(sourceCRSExtent));
+                    bool extentIntersectsTarget =
+                        targetCRSExtent &&
+                        extent->intersects(NN_NO_CHECK(targetCRSExtent));
+                    if (!extentIntersectsSource || !extentIntersectsTarget) {
+                        continue;
+                    }
+                }
+            }
+            res.emplace_back(op);
+        }
+    }
+
+    // ----------------------------------------------------------------------
+
+    void sort() {
+
+        // Precompute a number of parameters for each operation that will be
+        // useful for the sorting.
+        std::map<CoordinateOperation *, PrecomputedOpCharacteristics> map;
+        const auto gridAvailabilityUse = context->getGridAvailabilityUse();
+        for (const auto &op : res) {
+            bool dummy = false;
+            auto extentOp = getExtent(op, true, dummy);
+            double area = 0.0;
+            if (extentOp) {
+                if (areaOfInterest) {
+                    area = getPseudoArea(
+                        extentOp->intersection(NN_NO_CHECK(areaOfInterest)));
+                } else if (sourceCRSExtent && targetCRSExtent) {
+                    auto x =
+                        extentOp->intersection(NN_NO_CHECK(sourceCRSExtent));
+                    auto y =
+                        extentOp->intersection(NN_NO_CHECK(targetCRSExtent));
+                    area = getPseudoArea(x) + getPseudoArea(y) -
+                           ((x && y)
+                                ? getPseudoArea(x->intersection(NN_NO_CHECK(y)))
+                                : 0.0);
+                } else if (sourceCRSExtent) {
+                    area = getPseudoArea(
+                        extentOp->intersection(NN_NO_CHECK(sourceCRSExtent)));
+                } else if (targetCRSExtent) {
+                    area = getPseudoArea(
+                        extentOp->intersection(NN_NO_CHECK(targetCRSExtent)));
+                } else {
+                    area = getPseudoArea(extentOp);
+                }
+            }
+
+            bool hasGrids = false;
+            bool gridsAvailable = true;
+            bool gridsKnown = true;
+            if (context->getAuthorityFactory() &&
+                (gridAvailabilityUse ==
+                     CoordinateOperationContext::GridAvailabilityUse::
+                         USE_FOR_SORTING ||
+                 gridAvailabilityUse ==
+                     CoordinateOperationContext::GridAvailabilityUse::
+                         IGNORE_GRID_AVAILABILITY)) {
+                const auto gridsNeeded = op->gridsNeeded(
+                    context->getAuthorityFactory()->databaseContext());
+                for (const auto &gridDesc : gridsNeeded) {
+                    hasGrids = true;
+                    if (gridAvailabilityUse ==
+                            CoordinateOperationContext::GridAvailabilityUse::
+                                USE_FOR_SORTING &&
+                        !gridDesc.available) {
+                        gridsAvailable = false;
+                    }
+                    if (gridDesc.packageName.empty()) {
+                        gridsKnown = false;
+                    }
+                }
+            }
+
+            const auto stepCount = getStepCount(op);
+
+            map[op.get()] = PrecomputedOpCharacteristics(
+                area, getAccuracy(op), hasGrids, gridsAvailable, gridsKnown,
+                stepCount);
+        }
+
+        // Sort !
+        std::sort(res.begin(), res.end(), SortFunction(map));
+    }
+
+    // ----------------------------------------------------------------------
+
+    void removeSyntheticNullTransforms() {
+
+        // If we have more than one result, and than the last result is the
+        // default "Null geographic offset" or "Null geocentric translation"
+        // operations we have synthetized, remove it as
+        // all previous results are necessarily better
+        if (hasOpThatContainsAreaOfInterest && res.size() > 1) {
+            const std::string &name = res.back()->nameStr();
+            if (name.find(NULL_GEOGRAPHIC_OFFSET) != std::string::npos ||
+                name.find(NULL_GEOCENTRIC_TRANSLATION) != std::string::npos) {
+                std::vector<CoordinateOperationNNPtr> resTemp;
+                for (size_t i = 0; i < res.size() - 1; i++) {
+                    resTemp.emplace_back(res[i]);
+                }
+                res = std::move(resTemp);
+            }
+        }
+    }
+
+    // ----------------------------------------------------------------------
+
+    void removeUninterestingOps() {
+
+        // Eliminate operations that bring nothing, ie for a given area of use,
+        // do not keep operations that have greater accuracy. Actually we must
+        // be a bit more subtle than that, and take into account grid
+        // availability
+        std::vector<CoordinateOperationNNPtr> resTemp;
+        metadata::ExtentPtr lastExtent;
+        double lastAccuracy = -1;
+        bool lastHasGrids = false;
+        bool lastGridsAvailable = true;
+        std::set<std::set<std::string>> setOfSetOfGrids;
+        size_t lastStepCount = 0;
+        CoordinateOperationPtr lastOp;
+
+        bool first = true;
+        for (const auto &op : res) {
+            const auto curAccuracy = getAccuracy(op);
+            bool dummy = false;
+            const auto curExtent = getExtent(op, true, dummy);
+            bool curHasGrids = false;
+            bool curGridsAvailable = true;
+            std::set<std::string> curSetOfGrids;
+
+            const auto curStepCount = getStepCount(op);
+
+            if (context->getAuthorityFactory()) {
+                const auto gridsNeeded = op->gridsNeeded(
+                    context->getAuthorityFactory()->databaseContext());
+                for (const auto &gridDesc : gridsNeeded) {
+                    curHasGrids = true;
+                    curSetOfGrids.insert(gridDesc.shortName);
+                    if (!gridDesc.available) {
+                        curGridsAvailable = false;
+                    }
+                }
+            }
+
+            if (first) {
+                resTemp.emplace_back(op);
+
+                lastHasGrids = curHasGrids;
+                lastGridsAvailable = curGridsAvailable;
+                first = false;
+            } else {
+                if (lastOp->_isEquivalentTo(op.get())) {
+                    continue;
+                }
+                const bool sameExtent =
+                    ((!curExtent && !lastExtent) ||
+                     (curExtent && lastExtent &&
+                      curExtent->contains(NN_NO_CHECK(lastExtent)) &&
+                      lastExtent->contains(NN_NO_CHECK(curExtent))));
+                if (((curAccuracy > lastAccuracy && lastAccuracy >= 0) ||
+                     (curAccuracy < 0 && lastAccuracy >= 0)) &&
+                    sameExtent) {
+                    // If that set of grids has always been used for that
+                    // extent,
+                    // no need to add them again
+                    if (setOfSetOfGrids.find(curSetOfGrids) !=
+                        setOfSetOfGrids.end()) {
+                        continue;
+                    }
+                    // If we have already found a operation without grids for
+                    // that extent, no need to add any lower accuracy operation
+                    if (!lastHasGrids) {
+                        continue;
+                    }
+                    // If we had only operations involving grids, but one
+                    // past operation had available grids, no need to add
+                    // the new one.
+                    if (curHasGrids && curGridsAvailable &&
+                        lastGridsAvailable) {
+                        continue;
+                    }
+                } else if (curAccuracy == lastAccuracy && sameExtent) {
+                    if (curStepCount > lastStepCount) {
+                        continue;
+                    }
+                }
+
+                resTemp.emplace_back(op);
+
+                if (sameExtent) {
+                    if (!curHasGrids) {
+                        lastHasGrids = false;
+                    }
+                    if (curGridsAvailable) {
+                        lastGridsAvailable = true;
+                    }
+                } else {
+                    setOfSetOfGrids.clear();
+
+                    lastHasGrids = curHasGrids;
+                    lastGridsAvailable = curGridsAvailable;
+                }
+            }
+
+            lastOp = op.as_nullable();
+            lastStepCount = curStepCount;
+            lastExtent = curExtent;
+            lastAccuracy = curAccuracy;
+            if (!curSetOfGrids.empty()) {
+                setOfSetOfGrids.insert(curSetOfGrids);
+            }
+        }
+        res = std::move(resTemp);
+    }
+
+    // ----------------------------------------------------------------------
+
+    // cppcheck-suppress functionStatic
+    void removeDuplicateOps() {
+
+        if (res.size() <= 1) {
+            return;
+        }
+
+        // When going from EPSG:4807 (NTF Paris) to EPSG:4171 (RGC93), we get
+        // EPSG:7811, NTF (Paris) to RGF93 (2), 1 m
+        // and unknown id, NTF (Paris) to NTF (1) + Inverse of RGF93 to NTF (2),
+        // 1 m
+        // both have same PROJ string and extent
+        // Do not keep the later (that has more steps) as it adds no value.
+
+        std::set<std::string> setPROJPlusExtent;
+        std::vector<CoordinateOperationNNPtr> resTemp;
+        for (const auto &op : res) {
+            auto formatter = io::PROJStringFormatter::create();
+            try {
+                std::string key(op->exportToPROJString(formatter.get()));
+                bool dummy = false;
+                auto extentOp = getExtent(op, true, dummy);
+                if (extentOp) {
+                    const auto &geogElts = extentOp->geographicElements();
+                    if (geogElts.size() == 1) {
+                        auto bbox = dynamic_cast<
+                            const metadata::GeographicBoundingBox *>(
+                            geogElts[0].get());
+                        if (bbox) {
+                            double w = bbox->westBoundLongitude();
+                            double s = bbox->southBoundLatitude();
+                            double e = bbox->eastBoundLongitude();
+                            double n = bbox->northBoundLatitude();
+                            key += "-";
+                            key += toString(w);
+                            key += "-";
+                            key += toString(s);
+                            key += "-";
+                            key += toString(e);
+                            key += "-";
+                            key += toString(n);
+                        }
+                    }
+                }
+
+                if (setPROJPlusExtent.find(key) == setPROJPlusExtent.end()) {
+                    resTemp.emplace_back(op);
+                    setPROJPlusExtent.insert(key);
+                }
+            } catch (const std::exception &) {
+                resTemp.emplace_back(op);
+            }
+        }
+        res = std::move(resTemp);
+    }
+};
+
+// ---------------------------------------------------------------------------
+
+/** \brief Filter operations and sort them given context.
+ *
+ * If a desired accuracy is specified, only keep operations whose accuracy
+ * is at least the desired one.
+ * If an area of interest is specified, only keep operations whose area of
+ * use include the area of interest.
+ * Then sort remaining operations by descending area of use, and increasing
+ * accuracy.
+ */
+static std::vector<CoordinateOperationNNPtr>
+filterAndSort(const std::vector<CoordinateOperationNNPtr> &sourceList,
+              const CoordinateOperationContextNNPtr &context,
+              const crs::CRSNNPtr &sourceCRS, const crs::CRSNNPtr &targetCRS) {
+    return FilterResults(sourceList, context, sourceCRS, targetCRS, false)
+        .andSort()
+        .getRes();
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+// Apply the inverse() method on all elements of the input list
+static std::vector<CoordinateOperationNNPtr>
+applyInverse(const std::vector<CoordinateOperationNNPtr> &list) {
+    auto res = list;
+    for (auto &op : res) {
+        op = op->inverse();
+    }
+    return res;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+// Look in the authority registry for operations from sourceCRS to targetCRS
+static std::vector<CoordinateOperationNNPtr>
+findOpsInRegistryDirect(const crs::CRSNNPtr &sourceCRS,
+                        const crs::CRSNNPtr &targetCRS,
+                        const CoordinateOperationContextNNPtr &context) {
+    const auto &authFactory = context->getAuthorityFactory();
+    assert(authFactory);
+    const auto &authFactoryName = authFactory->getAuthority();
+
+    for (const auto &idSrc : sourceCRS->identifiers()) {
+        const auto &srcAuthName = *(idSrc->codeSpace());
+        const auto &srcCode = idSrc->code();
+        if (!srcAuthName.empty()) {
+            for (const auto &idTarget : targetCRS->identifiers()) {
+                const auto &targetAuthName = *(idTarget->codeSpace());
+                const auto &targetCode = idTarget->code();
+                if (!targetAuthName.empty()) {
+                    std::vector<std::string> authorities;
+                    if (authFactoryName == "any") {
+                        authorities.emplace_back();
+                    }
+                    if (authFactoryName.empty()) {
+                        authorities = authFactory->databaseContext()
+                                          ->getAllowedAuthorities(
+                                              srcAuthName, targetAuthName);
+                        if (authorities.empty()) {
+                            authorities.emplace_back();
+                        }
+                    } else {
+                        authorities.emplace_back(authFactoryName);
+                    }
+                    for (const auto &authority : authorities) {
+                        const auto tmpAuthFactory =
+                            io::AuthorityFactory::create(
+                                authFactory->databaseContext(),
+                                authority == "any" ? std::string() : authority);
+                        auto res =
+                            tmpAuthFactory
+                                ->createFromCoordinateReferenceSystemCodes(
+                                    srcAuthName, srcCode, targetAuthName,
+                                    targetCode,
+                                    context->getUsePROJAlternativeGridNames(),
+                                    context->getGridAvailabilityUse() ==
+                                        CoordinateOperationContext::
+                                            GridAvailabilityUse::
+                                                DISCARD_OPERATION_IF_MISSING_GRID,
+                                    context->getDiscardSuperseded());
+                        if (!res.empty()) {
+                            return res;
+                        }
+                    }
+                }
+            }
+        }
+    }
+    return std::vector<CoordinateOperationNNPtr>();
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+// Look in the authority registry for operations from sourceCRS to targetCRS
+// using an intermediate pivot
+static std::vector<CoordinateOperationNNPtr> findsOpsInRegistryWithIntermediate(
+    const crs::CRSNNPtr &sourceCRS, const crs::CRSNNPtr &targetCRS,
+    const CoordinateOperationContextNNPtr &context) {
+    if (!context->getAllowUseIntermediateCRS()) {
+        return std::vector<CoordinateOperationNNPtr>();
+    }
+
+    const auto &authFactory = context->getAuthorityFactory();
+    assert(authFactory);
+    const auto &authFactoryName = authFactory->getAuthority();
+
+    for (const auto &idSrc : sourceCRS->identifiers()) {
+        const auto &srcAuthName = *(idSrc->codeSpace());
+        const auto &srcCode = idSrc->code();
+        if (!srcAuthName.empty()) {
+            for (const auto &idTarget : targetCRS->identifiers()) {
+                const auto &targetAuthName = *(idTarget->codeSpace());
+                const auto &targetCode = idTarget->code();
+                if (!targetAuthName.empty()) {
+                    std::vector<std::string> authorities;
+                    if (authFactoryName == "any") {
+                        authorities.emplace_back();
+                    }
+                    if (authFactoryName.empty()) {
+                        authorities = authFactory->databaseContext()
+                                          ->getAllowedAuthorities(
+                                              srcAuthName, targetAuthName);
+                        if (authorities.empty()) {
+                            authorities.emplace_back();
+                        }
+                    } else {
+                        authorities.emplace_back(authFactoryName);
+                    }
+                    for (const auto &authority : authorities) {
+                        const auto tmpAuthFactory =
+                            io::AuthorityFactory::create(
+                                authFactory->databaseContext(),
+                                authority == "any" ? std::string() : authority);
+
+                        auto res =
+                            tmpAuthFactory->createFromCRSCodesWithIntermediates(
+                                srcAuthName, srcCode, targetAuthName,
+                                targetCode,
+                                context->getUsePROJAlternativeGridNames(),
+                                context->getGridAvailabilityUse() ==
+                                    CoordinateOperationContext::
+                                        GridAvailabilityUse::
+                                            DISCARD_OPERATION_IF_MISSING_GRID,
+                                context->getDiscardSuperseded(),
+                                context->getIntermediateCRS());
+                        if (!res.empty()) {
+                            return res;
+                        }
+                    }
+                }
+            }
+        }
+    }
+    return std::vector<CoordinateOperationNNPtr>();
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static TransformationNNPtr
+createNullGeographicOffset(const crs::CRSNNPtr &sourceCRS,
+                           const crs::CRSNNPtr &targetCRS) {
+    std::string name(NULL_GEOGRAPHIC_OFFSET);
+    name += " from ";
+    name += sourceCRS->nameStr();
+    name += " to ";
+    name += targetCRS->nameStr();
+
+    const auto &sourceCRSExtent = getExtent(sourceCRS);
+    const auto &targetCRSExtent = getExtent(targetCRS);
+    const bool sameExtent =
+        sourceCRSExtent && targetCRSExtent &&
+        sourceCRSExtent->_isEquivalentTo(
+            targetCRSExtent.get(), util::IComparable::Criterion::EQUIVALENT);
+
+    util::PropertyMap map;
+    map.set(common::IdentifiedObject::NAME_KEY, name)
+        .set(common::ObjectUsage::DOMAIN_OF_VALIDITY_KEY,
+             sameExtent ? NN_NO_CHECK(sourceCRSExtent)
+                        : metadata::Extent::WORLD);
+    const common::Angle angle0(0);
+    if (dynamic_cast<const crs::SingleCRS *>(sourceCRS.get())
+                ->coordinateSystem()
+                ->axisList()
+                .size() == 3 ||
+        dynamic_cast<const crs::SingleCRS *>(targetCRS.get())
+                ->coordinateSystem()
+                ->axisList()
+                .size() == 3) {
+        return Transformation::createGeographic3DOffsets(
+            map, sourceCRS, targetCRS, angle0, angle0, common::Length(0), {});
+    } else {
+        return Transformation::createGeographic2DOffsets(
+            map, sourceCRS, targetCRS, angle0, angle0, {});
+    }
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+struct MyPROJStringExportableGeodToGeod final
+    : public io::IPROJStringExportable {
+    crs::GeodeticCRSPtr geodSrc{};
+    crs::GeodeticCRSPtr geodDst{};
+
+    MyPROJStringExportableGeodToGeod(const crs::GeodeticCRSPtr &geodSrcIn,
+                                     const crs::GeodeticCRSPtr &geodDstIn)
+        : geodSrc(geodSrcIn), geodDst(geodDstIn) {}
+
+    ~MyPROJStringExportableGeodToGeod() override;
+
+    void
+        // cppcheck-suppress functionStatic
+        _exportToPROJString(io::PROJStringFormatter *formatter) const override {
+
+        formatter->startInversion();
+        geodSrc->_exportToPROJString(formatter);
+        formatter->stopInversion();
+        geodDst->_exportToPROJString(formatter);
+    }
+};
+
+MyPROJStringExportableGeodToGeod::~MyPROJStringExportableGeodToGeod() = default;
+
+// ---------------------------------------------------------------------------
+
+struct MyPROJStringExportableHorizVertical final
+    : public io::IPROJStringExportable {
+    CoordinateOperationPtr horizTransform{};
+    CoordinateOperationPtr verticalTransform{};
+    crs::GeographicCRSPtr geogDst{};
+
+    MyPROJStringExportableHorizVertical(
+        const CoordinateOperationPtr &horizTransformIn,
+        const CoordinateOperationPtr &verticalTransformIn,
+        const crs::GeographicCRSPtr &geogDstIn)
+        : horizTransform(horizTransformIn),
+          verticalTransform(verticalTransformIn), geogDst(geogDstIn) {}
+
+    ~MyPROJStringExportableHorizVertical() override;
+
+    void
+        // cppcheck-suppress functionStatic
+        _exportToPROJString(io::PROJStringFormatter *formatter) const override {
+
+        formatter->setOmitZUnitConversion(true);
+        horizTransform->_exportToPROJString(formatter);
+
+        formatter->startInversion();
+        geogDst->addAngularUnitConvertAndAxisSwap(formatter);
+        formatter->stopInversion();
+        formatter->setOmitZUnitConversion(false);
+
+        verticalTransform->_exportToPROJString(formatter);
+
+        formatter->setOmitZUnitConversion(true);
+        geogDst->addAngularUnitConvertAndAxisSwap(formatter);
+        formatter->setOmitZUnitConversion(false);
+    }
+};
+
+MyPROJStringExportableHorizVertical::~MyPROJStringExportableHorizVertical() =
+    default;
+
+// ---------------------------------------------------------------------------
+
+struct MyPROJStringExportableHorizVerticalHorizPROJBased final
+    : public io::IPROJStringExportable {
+    CoordinateOperationPtr opSrcCRSToGeogCRS{};
+    CoordinateOperationPtr verticalTransform{};
+    CoordinateOperationPtr opGeogCRStoDstCRS{};
+    crs::GeographicCRSPtr interpolationGeogCRS{};
+
+    MyPROJStringExportableHorizVerticalHorizPROJBased(
+        const CoordinateOperationPtr &opSrcCRSToGeogCRSIn,
+        const CoordinateOperationPtr &verticalTransformIn,
+        const CoordinateOperationPtr &opGeogCRStoDstCRSIn,
+        const crs::GeographicCRSPtr &interpolationGeogCRSIn)
+        : opSrcCRSToGeogCRS(opSrcCRSToGeogCRSIn),
+          verticalTransform(verticalTransformIn),
+          opGeogCRStoDstCRS(opGeogCRStoDstCRSIn),
+          interpolationGeogCRS(interpolationGeogCRSIn) {}
+
+    ~MyPROJStringExportableHorizVerticalHorizPROJBased() override;
+
+    void
+        // cppcheck-suppress functionStatic
+        _exportToPROJString(io::PROJStringFormatter *formatter) const override {
+
+        formatter->setOmitZUnitConversion(true);
+
+        opSrcCRSToGeogCRS->_exportToPROJString(formatter);
+
+        formatter->startInversion();
+        interpolationGeogCRS->addAngularUnitConvertAndAxisSwap(formatter);
+        formatter->stopInversion();
+
+        formatter->setOmitZUnitConversion(false);
+
+        verticalTransform->_exportToPROJString(formatter);
+
+        formatter->setOmitZUnitConversion(true);
+
+        interpolationGeogCRS->addAngularUnitConvertAndAxisSwap(formatter);
+
+        opGeogCRStoDstCRS->_exportToPROJString(formatter);
+
+        formatter->setOmitZUnitConversion(false);
+    }
+};
+
+MyPROJStringExportableHorizVerticalHorizPROJBased::
+    ~MyPROJStringExportableHorizVerticalHorizPROJBased() = default;
+}
+NS_PROJ_END
+
+#if 0
+namespace dropbox{ namespace oxygen {
+template<> nn<std::shared_ptr<NS_PROJ::operation::MyPROJStringExportableGeodToGeod>>::~nn() = default;
+template<> nn<std::shared_ptr<NS_PROJ::operation::MyPROJStringExportableHorizVertical>>::~nn() = default;
+template<> nn<std::shared_ptr<NS_PROJ::operation::MyPROJStringExportableHorizVerticalHorizPROJBased>>::~nn() = default;
+}}
+#endif
+
+NS_PROJ_START
+namespace operation {
+
+// ---------------------------------------------------------------------------
+
+static std::string buildTransfName(const std::string &srcName,
+                                   const std::string &targetName) {
+    std::string name("Transformation from ");
+    name += srcName;
+    name += " to ";
+    name += targetName;
+    return name;
+}
+
+// ---------------------------------------------------------------------------
+
+static CoordinateOperationNNPtr
+createGeodToGeodPROJBased(const crs::CRSNNPtr &geodSrc,
+                          const crs::CRSNNPtr &geodDst) {
+
+    auto exportable = util::nn_make_shared<MyPROJStringExportableGeodToGeod>(
+        util::nn_dynamic_pointer_cast<crs::GeodeticCRS>(geodSrc),
+        util::nn_dynamic_pointer_cast<crs::GeodeticCRS>(geodDst));
+
+    auto properties = util::PropertyMap().set(
+        common::IdentifiedObject::NAME_KEY,
+        buildTransfName(geodSrc->nameStr(), geodDst->nameStr()));
+    return createPROJBased(properties, exportable, geodSrc, geodDst);
+}
+
+// ---------------------------------------------------------------------------
+
+static CoordinateOperationNNPtr createHorizVerticalPROJBased(
+    const crs::CRSNNPtr &sourceCRS, const crs::CRSNNPtr &targetCRS,
+    const operation::CoordinateOperationNNPtr &horizTransform,
+    const operation::CoordinateOperationNNPtr &verticalTransform) {
+
+    auto geogDst = util::nn_dynamic_pointer_cast<crs::GeographicCRS>(targetCRS);
+    assert(geogDst);
+
+    auto exportable = util::nn_make_shared<MyPROJStringExportableHorizVertical>(
+        horizTransform, verticalTransform, geogDst);
+
+    bool dummy = false;
+    auto ops = std::vector<CoordinateOperationNNPtr>{horizTransform,
+                                                     verticalTransform};
+    auto extent = getExtent(ops, true, dummy);
+    auto properties = util::PropertyMap();
+    properties.set(common::IdentifiedObject::NAME_KEY,
+                   computeConcatenatedName(ops));
+
+    if (extent) {
+        properties.set(common::ObjectUsage::DOMAIN_OF_VALIDITY_KEY,
+                       NN_NO_CHECK(extent));
+    }
+
+    std::vector<metadata::PositionalAccuracyNNPtr> accuracies;
+    const double accuracy = getAccuracy(ops);
+    if (accuracy >= 0.0) {
+        accuracies.emplace_back(
+            metadata::PositionalAccuracy::create(toString(accuracy)));
+    }
+
+    return createPROJBased(properties, exportable, sourceCRS, targetCRS,
+                           accuracies);
+}
+
+// ---------------------------------------------------------------------------
+
+static CoordinateOperationNNPtr createHorizVerticalHorizPROJBased(
+    const crs::CRSNNPtr &sourceCRS, const crs::CRSNNPtr &targetCRS,
+    const operation::CoordinateOperationNNPtr &opSrcCRSToGeogCRS,
+    const operation::CoordinateOperationNNPtr &verticalTransform,
+    const operation::CoordinateOperationNNPtr &opGeogCRStoDstCRS,
+    const crs::GeographicCRSPtr &interpolationGeogCRS) {
+
+    auto exportable =
+        util::nn_make_shared<MyPROJStringExportableHorizVerticalHorizPROJBased>(
+            opSrcCRSToGeogCRS, verticalTransform, opGeogCRStoDstCRS,
+            interpolationGeogCRS);
+
+    bool dummy = false;
+    auto ops = std::vector<CoordinateOperationNNPtr>{
+        opSrcCRSToGeogCRS, verticalTransform, opGeogCRStoDstCRS};
+    auto extent = getExtent(ops, true, dummy);
+    auto properties = util::PropertyMap();
+    properties.set(common::IdentifiedObject::NAME_KEY,
+                   computeConcatenatedName(ops));
+
+    if (extent) {
+        properties.set(common::ObjectUsage::DOMAIN_OF_VALIDITY_KEY,
+                       NN_NO_CHECK(extent));
+    }
+
+    std::vector<metadata::PositionalAccuracyNNPtr> accuracies;
+    const double accuracy = getAccuracy(ops);
+    if (accuracy >= 0.0) {
+        accuracies.emplace_back(
+            metadata::PositionalAccuracy::create(toString(accuracy)));
+    }
+
+    return createPROJBased(properties, exportable, sourceCRS, targetCRS,
+                           accuracies);
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+ConversionNNPtr CoordinateOperationFactory::Private::createGeographicGeocentric(
+    const crs::CRSNNPtr &sourceCRS, const crs::CRSNNPtr &targetCRS) {
+    auto properties = util::PropertyMap().set(
+        common::IdentifiedObject::NAME_KEY,
+        buildOpName("Conversion", sourceCRS, targetCRS));
+    auto conv = Conversion::createGeographicGeocentric(properties);
+    conv->setCRSs(sourceCRS, targetCRS, nullptr);
+    return conv;
+}
+
+// ---------------------------------------------------------------------------
+
+std::vector<CoordinateOperationNNPtr>
+CoordinateOperationFactory::Private::createOperationsGeogToGeog(
+    std::vector<CoordinateOperationNNPtr> &res, const crs::CRSNNPtr &sourceCRS,
+    const crs::CRSNNPtr &targetCRS, const crs::GeographicCRS *geogSrc,
+    const crs::GeographicCRS *geogDst) {
+
+    assert(sourceCRS.get() == geogSrc);
+    assert(targetCRS.get() == geogDst);
+    const bool allowEmptyIntersection = true;
+
+    const auto &src_pm = geogSrc->primeMeridian()->longitude();
+    const auto &dst_pm = geogDst->primeMeridian()->longitude();
+    auto offset_pm =
+        (src_pm.unit() == dst_pm.unit())
+            ? common::Angle(src_pm.value() - dst_pm.value(), src_pm.unit())
+            : common::Angle(
+                  src_pm.convertToUnit(common::UnitOfMeasure::DEGREE) -
+                      dst_pm.convertToUnit(common::UnitOfMeasure::DEGREE),
+                  common::UnitOfMeasure::DEGREE);
+
+    double vconvSrc = 1.0;
+    const auto &srcCS = geogSrc->coordinateSystem();
+    const auto &srcAxisList = srcCS->axisList();
+    if (srcAxisList.size() == 3) {
+        vconvSrc = srcAxisList[2]->unit().conversionToSI();
+    }
+    double vconvDst = 1.0;
+    const auto &dstCS = geogDst->coordinateSystem();
+    const auto &dstAxisList = dstCS->axisList();
+    if (dstAxisList.size() == 3) {
+        vconvDst = dstAxisList[2]->unit().conversionToSI();
+    }
+
+    std::string name(buildTransfName(geogSrc->nameStr(), geogDst->nameStr()));
+
+    // Do they differ by vertical units ?
+    if (vconvSrc != vconvDst &&
+        geogSrc->ellipsoid()->_isEquivalentTo(
+            geogDst->ellipsoid().get(),
+            util::IComparable::Criterion::EQUIVALENT)) {
+        if (offset_pm.value() == 0) {
+            // If only by vertical units, use a Change of Vertical
+            // Unit
+            // transformation
+            const double factor = vconvSrc / vconvDst;
+            auto conv = Conversion::createChangeVerticalUnit(
+                util::PropertyMap().set(common::IdentifiedObject::NAME_KEY,
+                                        name),
+                common::Scale(factor));
+            conv->setCRSs(sourceCRS, targetCRS, nullptr);
+            res.push_back(conv);
+            return res;
+        } else {
+            res.emplace_back(createGeodToGeodPROJBased(sourceCRS, targetCRS));
+            return res;
+        }
+    }
+
+    // Do the CRS differ only by their axis order ?
+    if (geogSrc->datum() != nullptr && geogDst->datum() != nullptr &&
+        geogSrc->datum()->_isEquivalentTo(
+            geogDst->datum().get(), util::IComparable::Criterion::EQUIVALENT) &&
+        !srcCS->_isEquivalentTo(dstCS.get(),
+                                util::IComparable::Criterion::EQUIVALENT)) {
+        auto srcOrder = srcCS->axisOrder();
+        auto dstOrder = dstCS->axisOrder();
+        if ((srcOrder == cs::EllipsoidalCS::AxisOrder::LAT_NORTH_LONG_EAST &&
+             dstOrder == cs::EllipsoidalCS::AxisOrder::LONG_EAST_LAT_NORTH) ||
+            (srcOrder == cs::EllipsoidalCS::AxisOrder::LONG_EAST_LAT_NORTH &&
+             dstOrder == cs::EllipsoidalCS::AxisOrder::LAT_NORTH_LONG_EAST)) {
+            auto conv = Conversion::createAxisOrderReversal(false);
+            conv->setCRSs(sourceCRS, targetCRS, nullptr);
+            res.emplace_back(conv);
+            return res;
+        }
+        if ((srcOrder ==
+                 cs::EllipsoidalCS::AxisOrder::LAT_NORTH_LONG_EAST_HEIGHT_UP &&
+             dstOrder ==
+                 cs::EllipsoidalCS::AxisOrder::LONG_EAST_LAT_NORTH_HEIGHT_UP) ||
+            (srcOrder ==
+                 cs::EllipsoidalCS::AxisOrder::LONG_EAST_LAT_NORTH_HEIGHT_UP &&
+             dstOrder ==
+                 cs::EllipsoidalCS::AxisOrder::LAT_NORTH_LONG_EAST_HEIGHT_UP)) {
+            auto conv = Conversion::createAxisOrderReversal(true);
+            conv->setCRSs(sourceCRS, targetCRS, nullptr);
+            res.emplace_back(conv);
+            return res;
+        }
+    }
+
+    std::vector<CoordinateOperationNNPtr> steps;
+    // If both are geographic and only differ by their prime
+    // meridian,
+    // apply a longitude rotation transformation.
+    if (geogSrc->ellipsoid()->_isEquivalentTo(
+            geogDst->ellipsoid().get(),
+            util::IComparable::Criterion::EQUIVALENT) &&
+        src_pm.getSIValue() != dst_pm.getSIValue()) {
+
+        steps.emplace_back(Transformation::createLongitudeRotation(
+            util::PropertyMap()
+                .set(common::IdentifiedObject::NAME_KEY, name)
+                .set(common::ObjectUsage::DOMAIN_OF_VALIDITY_KEY,
+                     metadata::Extent::WORLD),
+            sourceCRS, targetCRS, offset_pm));
+        // If only the target has a non-zero prime meridian, chain a
+        // null geographic offset and then the longitude rotation
+    } else if (src_pm.getSIValue() == 0 && dst_pm.getSIValue() != 0) {
+        auto datum = datum::GeodeticReferenceFrame::create(
+            util::PropertyMap(), geogDst->ellipsoid(),
+            util::optional<std::string>(), geogSrc->primeMeridian());
+        std::string interm_crs_name(geogDst->nameStr());
+        interm_crs_name += " altered to use prime meridian of ";
+        interm_crs_name += geogSrc->nameStr();
+        auto interm_crs =
+            util::nn_static_pointer_cast<crs::CRS>(crs::GeographicCRS::create(
+                util::PropertyMap()
+                    .set(common::IdentifiedObject::NAME_KEY, interm_crs_name)
+                    .set(common::ObjectUsage::DOMAIN_OF_VALIDITY_KEY,
+                         metadata::Extent::WORLD),
+                datum, dstCS));
+
+        steps.emplace_back(createNullGeographicOffset(sourceCRS, interm_crs));
+
+        steps.emplace_back(Transformation::createLongitudeRotation(
+            util::PropertyMap()
+                .set(common::IdentifiedObject::NAME_KEY,
+                     buildTransfName(geogSrc->nameStr(), interm_crs->nameStr()))
+                .set(common::ObjectUsage::DOMAIN_OF_VALIDITY_KEY,
+                     metadata::Extent::WORLD),
+            interm_crs, targetCRS, offset_pm));
+
+    } else {
+        // If the prime meridians are different, chain a longitude
+        // rotation and the null geographic offset.
+        if (src_pm.getSIValue() != dst_pm.getSIValue()) {
+            auto datum = datum::GeodeticReferenceFrame::create(
+                util::PropertyMap(), geogSrc->ellipsoid(),
+                util::optional<std::string>(), geogDst->primeMeridian());
+            std::string interm_crs_name(geogSrc->nameStr());
+            interm_crs_name += " altered to use prime meridian of ";
+            interm_crs_name += geogDst->nameStr();
+            auto interm_crs = util::nn_static_pointer_cast<crs::CRS>(
+                crs::GeographicCRS::create(
+                    util::PropertyMap().set(common::IdentifiedObject::NAME_KEY,
+                                            interm_crs_name),
+                    datum, srcCS));
+
+            steps.emplace_back(Transformation::createLongitudeRotation(
+                util::PropertyMap()
+                    .set(common::IdentifiedObject::NAME_KEY,
+                         buildTransfName(geogSrc->nameStr(),
+                                         interm_crs->nameStr()))
+                    .set(common::ObjectUsage::DOMAIN_OF_VALIDITY_KEY,
+                         metadata::Extent::WORLD),
+                sourceCRS, interm_crs, offset_pm));
+            steps.emplace_back(
+                createNullGeographicOffset(interm_crs, targetCRS));
+        } else {
+            steps.emplace_back(
+                createNullGeographicOffset(sourceCRS, targetCRS));
+        }
+    }
+
+    res.emplace_back(ConcatenatedOperation::createComputeMetadata(
+        steps, !allowEmptyIntersection));
+    return res;
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+static bool hasIdentifiers(const CoordinateOperationNNPtr &op) {
+    if (!op->identifiers().empty()) {
+        return true;
+    }
+    auto concatenated = dynamic_cast<const ConcatenatedOperation *>(op.get());
+    if (concatenated) {
+        for (const auto &subOp : concatenated->operations()) {
+            if (hasIdentifiers(subOp)) {
+                return true;
+            }
+        }
+    }
+    return false;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+static std::vector<crs::CRSNNPtr>
+findCandidateGeodCRSForDatum(const io::AuthorityFactoryPtr &authFactory,
+                             const datum::GeodeticReferenceFramePtr &datum) {
+    std::vector<crs::CRSNNPtr> candidates;
+    for (const auto &id : datum->identifiers()) {
+        const auto &authName = *(id->codeSpace());
+        const auto &code = id->code();
+        if (!authName.empty()) {
+            auto l_candidates = authFactory->createGeodeticCRSFromDatum(
+                authName, code, std::string());
+            for (const auto &candidate : l_candidates) {
+                candidates.emplace_back(candidate);
+            }
+        }
+    }
+    return candidates;
+}
+
+// ---------------------------------------------------------------------------
+
+static bool isNullTransformation(const std::string &name) {
+
+    return starts_with(name, NULL_GEOCENTRIC_TRANSLATION) ||
+           starts_with(name, NULL_GEOGRAPHIC_OFFSET);
+}
+
+// ---------------------------------------------------------------------------
+
+void CoordinateOperationFactory::Private::createOperationsWithDatumPivot(
+    std::vector<CoordinateOperationNNPtr> &res, const crs::CRSNNPtr &sourceCRS,
+    const crs::CRSNNPtr &targetCRS, const crs::GeodeticCRS *geodSrc,
+    const crs::GeodeticCRS *geodDst, Private::Context &context) {
+
+    const bool allowEmptyIntersection = true;
+
+    struct CreateOperationsWithDatumPivotAntiRecursion {
+        Context &context;
+
+        explicit CreateOperationsWithDatumPivotAntiRecursion(Context &contextIn)
+            : context(contextIn) {
+            assert(!context.inCreateOperationsWithDatumPivotAntiRecursion);
+            context.inCreateOperationsWithDatumPivotAntiRecursion = true;
+        }
+
+        ~CreateOperationsWithDatumPivotAntiRecursion() {
+            context.inCreateOperationsWithDatumPivotAntiRecursion = false;
+        }
+    };
+    CreateOperationsWithDatumPivotAntiRecursion guard(context);
+
+    const auto &authFactory = context.context->getAuthorityFactory();
+    const auto candidatesSrcGeod(
+        findCandidateGeodCRSForDatum(authFactory, geodSrc->datum()));
+    const auto candidatesDstGeod(
+        findCandidateGeodCRSForDatum(authFactory, geodDst->datum()));
+
+    auto createTransformations = [&](const crs::CRSNNPtr &candidateSrcGeod,
+                                     const crs::CRSNNPtr &candidateDstGeod,
+                                     const CoordinateOperationNNPtr &opFirst,
+                                     bool isNullFirst) {
+        const auto opsSecond =
+            createOperations(candidateSrcGeod, candidateDstGeod, context);
+        const auto opsThird =
+            createOperations(candidateDstGeod, targetCRS, context);
+        assert(!opsThird.empty());
+
+        for (auto &opSecond : opsSecond) {
+            // Check that it is not a transformation synthetized by
+            // ourselves
+            if (!hasIdentifiers(opSecond)) {
+                continue;
+            }
+            // And even if it is a referenced transformation, check that
+            // it is not a trivial one
+            auto so = dynamic_cast<const SingleOperation *>(opSecond.get());
+            if (so && isAxisOrderReversal(so->method()->getEPSGCode())) {
+                continue;
+            }
+
+            std::vector<CoordinateOperationNNPtr> subOps;
+            if (isNullFirst) {
+                opSecond->setCRSs(
+                    sourceCRS, NN_CHECK_ASSERT(opSecond->targetCRS()), nullptr);
+            } else {
+                subOps.emplace_back(opFirst);
+            }
+            if (isNullTransformation(opsThird[0]->nameStr())) {
+                opSecond->setCRSs(NN_CHECK_ASSERT(opSecond->sourceCRS()),
+                                  targetCRS, nullptr);
+                subOps.emplace_back(opSecond);
+            } else {
+                subOps.emplace_back(opSecond);
+                subOps.emplace_back(opsThird[0]);
+            }
+            res.emplace_back(ConcatenatedOperation::createComputeMetadata(
+                subOps, !allowEmptyIntersection));
+        }
+    };
+
+    // Start in priority with candidates that have exactly the same name as
+    // the sourcCRS and targetCRS. Typically for the case of init=IGNF:XXXX
+    for (const auto &candidateSrcGeod : candidatesSrcGeod) {
+        if (candidateSrcGeod->nameStr() == sourceCRS->nameStr()) {
+            for (const auto &candidateDstGeod : candidatesDstGeod) {
+                if (candidateDstGeod->nameStr() == targetCRS->nameStr()) {
+                    const auto opsFirst =
+                        createOperations(sourceCRS, candidateSrcGeod, context);
+                    assert(!opsFirst.empty());
+                    const bool isNullFirst =
+                        isNullTransformation(opsFirst[0]->nameStr());
+                    createTransformations(candidateSrcGeod, candidateDstGeod,
+                                          opsFirst[0], isNullFirst);
+                    if (!res.empty()) {
+                        return;
+                    }
+                    break;
+                }
+            }
+            break;
+        }
+    }
+
+    for (const auto &candidateSrcGeod : candidatesSrcGeod) {
+        const auto opsFirst =
+            createOperations(sourceCRS, candidateSrcGeod, context);
+        assert(!opsFirst.empty());
+        const bool isNullFirst = isNullTransformation(opsFirst[0]->nameStr());
+
+        for (const auto &candidateDstGeod : candidatesDstGeod) {
+            createTransformations(candidateSrcGeod, candidateDstGeod,
+                                  opsFirst[0], isNullFirst);
+        }
+        if (!res.empty()) {
+            return;
+        }
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+static CoordinateOperationNNPtr
+createNullGeocentricTranslation(const crs::CRSNNPtr &sourceCRS,
+                                const crs::CRSNNPtr &targetCRS) {
+    std::string name(NULL_GEOCENTRIC_TRANSLATION);
+    name += " from ";
+    name += sourceCRS->nameStr();
+    name += " to ";
+    name += targetCRS->nameStr();
+
+    return util::nn_static_pointer_cast<CoordinateOperation>(
+        Transformation::createGeocentricTranslations(
+            util::PropertyMap()
+                .set(common::IdentifiedObject::NAME_KEY, name)
+                .set(common::ObjectUsage::DOMAIN_OF_VALIDITY_KEY,
+                     metadata::Extent::WORLD),
+            sourceCRS, targetCRS, 0.0, 0.0, 0.0, {}));
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+bool CoordinateOperationFactory::Private::hasPerfectAccuracyResult(
+    const std::vector<CoordinateOperationNNPtr> &res, const Context &context) {
+    auto resTmp = FilterResults(res, context.context, context.sourceCRS,
+                                context.targetCRS, true)
+                      .getRes();
+    for (const auto &op : resTmp) {
+        const double acc = getAccuracy(op);
+        if (acc == 0.0) {
+            return true;
+        }
+    }
+    return false;
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+std::vector<CoordinateOperationNNPtr>
+CoordinateOperationFactory::Private::createOperations(
+    const crs::CRSNNPtr &sourceCRS, const crs::CRSNNPtr &targetCRS,
+    Private::Context &context) {
+
+    std::vector<CoordinateOperationNNPtr> res;
+    const bool allowEmptyIntersection = true;
+
+    const auto &sourceProj4Ext = sourceCRS->getExtensionProj4();
+    const auto &targetProj4Ext = targetCRS->getExtensionProj4();
+    if (!sourceProj4Ext.empty() || !targetProj4Ext.empty()) {
+
+        auto sourceProjExportable =
+            dynamic_cast<io::IPROJStringExportable *>(sourceCRS.get());
+        auto targetProjExportable =
+            dynamic_cast<io::IPROJStringExportable *>(targetCRS.get());
+        if (!sourceProjExportable) {
+            throw InvalidOperation("Source CRS is not PROJ exportable");
+        }
+        if (!targetProjExportable) {
+            throw InvalidOperation("Target CRS is not PROJ exportable");
+        }
+        auto projFormatter = io::PROJStringFormatter::create(
+            io::PROJStringFormatter::Convention::PROJ_4);
+        projFormatter->startInversion();
+        sourceProjExportable->_exportToPROJString(projFormatter.get());
+
+        auto geogSrc =
+            dynamic_cast<const crs::GeographicCRS *>(sourceCRS.get());
+        if (geogSrc) {
+            auto proj5Formatter = io::PROJStringFormatter::create(
+                io::PROJStringFormatter::Convention::PROJ_5);
+            geogSrc->addAngularUnitConvertAndAxisSwap(proj5Formatter.get());
+            projFormatter->ingestPROJString(proj5Formatter->toString());
+        }
+
+        projFormatter->stopInversion();
+
+        targetProjExportable->_exportToPROJString(projFormatter.get());
+
+        auto geogDst =
+            dynamic_cast<const crs::GeographicCRS *>(targetCRS.get());
+        if (geogDst) {
+            auto proj5Formatter = io::PROJStringFormatter::create(
+                io::PROJStringFormatter::Convention::PROJ_5);
+            geogDst->addAngularUnitConvertAndAxisSwap(proj5Formatter.get());
+            projFormatter->ingestPROJString(proj5Formatter->toString());
+        }
+
+        const auto PROJString = projFormatter->toString();
+        auto properties = util::PropertyMap().set(
+            common::IdentifiedObject::NAME_KEY,
+            buildTransfName(sourceCRS->nameStr(), targetCRS->nameStr()));
+        res.emplace_back(SingleOperation::createPROJBased(
+            properties, PROJString, sourceCRS, targetCRS, {}));
+        return res;
+    }
+
+    auto geodSrc = dynamic_cast<const crs::GeodeticCRS *>(sourceCRS.get());
+    auto geodDst = dynamic_cast<const crs::GeodeticCRS *>(targetCRS.get());
+
+    // First look-up if the registry provide us with operations.
+    auto derivedSrc = dynamic_cast<const crs::DerivedCRS *>(sourceCRS.get());
+    auto derivedDst = dynamic_cast<const crs::DerivedCRS *>(targetCRS.get());
+    if (context.context->getAuthorityFactory() &&
+        (derivedSrc == nullptr ||
+         !derivedSrc->baseCRS()->_isEquivalentTo(
+             targetCRS.get(), util::IComparable::Criterion::EQUIVALENT)) &&
+        (derivedDst == nullptr ||
+         !derivedDst->baseCRS()->_isEquivalentTo(
+             sourceCRS.get(), util::IComparable::Criterion::EQUIVALENT))) {
+
+        bool doFilterAndCheckPerfectOp = true;
+        res = findOpsInRegistryDirect(sourceCRS, targetCRS, context.context);
+        if (!sourceCRS->_isEquivalentTo(targetCRS.get())) {
+            auto resFromInverse = applyInverse(
+                findOpsInRegistryDirect(targetCRS, sourceCRS, context.context));
+            res.insert(res.end(), resFromInverse.begin(), resFromInverse.end());
+
+            // If we get at least a result with perfect accuracy, do not
+            // bother generating synthetic transforms.
+            if (hasPerfectAccuracyResult(res, context)) {
+                return res;
+            }
+
+            doFilterAndCheckPerfectOp = false;
+
+            // NAD27 to NAD83 has tens of results already. No need to look
+            // for a pivot
+            if (res.size() < 5 || getenv("PROJ_FORCE_SEARCH_PIVOT")) {
+                auto resWithIntermediate = findsOpsInRegistryWithIntermediate(
+                    sourceCRS, targetCRS, context.context);
+                res.insert(res.end(), resWithIntermediate.begin(),
+                           resWithIntermediate.end());
+                doFilterAndCheckPerfectOp = true;
+            }
+        }
+
+        if (res.empty() &&
+            !context.inCreateOperationsWithDatumPivotAntiRecursion && geodSrc &&
+            geodDst) {
+            // If we still didn't find a transformation, and that the source
+            // and target are GeodeticCRS, then go through their underlying
+            // datum to find potential transformations between other GeodeticRSs
+            // that are made of those datum
+            // The typical example is if transforming between two GeographicCRS,
+            // but transformations are only available between their
+            // corresponding geocentric CRS.
+            const auto &srcDatum = geodSrc->datum();
+            const bool srcHasDatumWithId =
+                srcDatum && !srcDatum->identifiers().empty();
+            const auto &dstDatum = geodDst->datum();
+            const bool dstHasDatumWithId =
+                dstDatum && !dstDatum->identifiers().empty();
+            if (srcHasDatumWithId && dstHasDatumWithId &&
+                !srcDatum->_isEquivalentTo(
+                    dstDatum.get(), util::IComparable::Criterion::EQUIVALENT)) {
+                createOperationsWithDatumPivot(res, sourceCRS, targetCRS,
+                                               geodSrc, geodDst, context);
+                doFilterAndCheckPerfectOp = !res.empty();
+            }
+        }
+
+        if (doFilterAndCheckPerfectOp) {
+            // If we get at least a result with perfect accuracy, do not bother
+            // generating synthetic transforms.
+            if (hasPerfectAccuracyResult(res, context)) {
+                return res;
+            }
+        }
+    }
+
+    // Special case if both CRS are geodetic
+    if (geodSrc && geodDst && !derivedSrc && !derivedDst) {
+
+        if (geodSrc->ellipsoid()->celestialBody() !=
+            geodDst->ellipsoid()->celestialBody()) {
+            throw util::UnsupportedOperationException(
+                "Source and target ellipsoid do not belong to the same "
+                "celestial body");
+        }
+
+        auto geogSrc =
+            dynamic_cast<const crs::GeographicCRS *>(sourceCRS.get());
+        auto geogDst =
+            dynamic_cast<const crs::GeographicCRS *>(targetCRS.get());
+        if (geogSrc && geogDst) {
+            return createOperationsGeogToGeog(res, sourceCRS, targetCRS,
+                                              geogSrc, geogDst);
+        }
+
+        const bool isSrcGeocentric = geodSrc->isGeocentric();
+        const bool isSrcGeographic = geogSrc != nullptr;
+        const bool isTargetGeocentric = geodDst->isGeocentric();
+        const bool isTargetGeographic = geogDst != nullptr;
+        if (((isSrcGeocentric && isTargetGeographic) ||
+             (isSrcGeographic && isTargetGeocentric)) &&
+            geodSrc->datum() != nullptr && geodDst->datum() != nullptr) {
+
+            // Same datum ?
+            if (geodSrc->datum()->_isEquivalentTo(
+                    geodDst->datum().get(),
+                    util::IComparable::Criterion::EQUIVALENT)) {
+                res.emplace_back(
+                    createGeographicGeocentric(sourceCRS, targetCRS));
+            } else if (isSrcGeocentric) {
+                std::string interm_crs_name(geogDst->nameStr());
+                interm_crs_name += " (geocentric)";
+                auto interm_crs = util::nn_static_pointer_cast<crs::CRS>(
+                    crs::GeodeticCRS::create(
+                        addDomains(util::PropertyMap().set(
+                                       common::IdentifiedObject::NAME_KEY,
+                                       interm_crs_name),
+                                   geogDst),
+                        NN_NO_CHECK(geogDst->datum()),
+                        NN_CHECK_ASSERT(
+                            util::nn_dynamic_pointer_cast<cs::CartesianCS>(
+                                geodSrc->coordinateSystem()))));
+                auto opFirst =
+                    createNullGeocentricTranslation(sourceCRS, interm_crs);
+                auto opSecond =
+                    createGeographicGeocentric(interm_crs, targetCRS);
+                res.emplace_back(ConcatenatedOperation::createComputeMetadata(
+                    {opFirst, opSecond}, !allowEmptyIntersection));
+            } else {
+                return applyInverse(
+                    createOperations(targetCRS, sourceCRS, context));
+            }
+
+            return res;
+        }
+
+        if (isSrcGeocentric && isTargetGeocentric) {
+            res.emplace_back(
+                createNullGeocentricTranslation(sourceCRS, targetCRS));
+            return res;
+        }
+
+        // Tranformation between two geodetic systems of unknown type
+        // This should normally not be triggered with "standard" CRS
+        res.emplace_back(createGeodToGeodPROJBased(sourceCRS, targetCRS));
+        return res;
+    }
+
+    // If the source is a derived CRS, then chain the inverse of its
+    // deriving conversion, with transforms from its baseCRS to the
+    // targetCRS
+    if (derivedSrc) {
+        auto opFirst = derivedSrc->derivingConversion()->inverse();
+        // Small optimization if the targetCRS is the baseCRS of the source
+        // derivedCRS.
+        if (derivedSrc->baseCRS()->_isEquivalentTo(
+                targetCRS.get(), util::IComparable::Criterion::EQUIVALENT)) {
+            res.emplace_back(opFirst);
+            return res;
+        }
+        auto opsSecond =
+            createOperations(derivedSrc->baseCRS(), targetCRS, context);
+        for (const auto &opSecond : opsSecond) {
+            try {
+                res.emplace_back(ConcatenatedOperation::createComputeMetadata(
+                    {opFirst, opSecond}, !allowEmptyIntersection));
+            } catch (const InvalidOperationEmptyIntersection &) {
+            }
+        }
+        return res;
+    }
+
+    // reverse of previous case
+    if (derivedDst) {
+        return applyInverse(createOperations(targetCRS, sourceCRS, context));
+    }
+
+    // boundCRS to a geogCRS that is the same as the hubCRS
+    auto boundSrc = dynamic_cast<const crs::BoundCRS *>(sourceCRS.get());
+    auto geogDst = dynamic_cast<const crs::GeographicCRS *>(targetCRS.get());
+    if (boundSrc && geogDst) {
+        const auto &hubSrc = boundSrc->hubCRS();
+        auto hubSrcGeog =
+            dynamic_cast<const crs::GeographicCRS *>(hubSrc.get());
+        auto geogCRSOfBaseOfBoundSrc =
+            boundSrc->baseCRS()->extractGeographicCRS();
+        if (hubSrcGeog && geogCRSOfBaseOfBoundSrc &&
+            (hubSrcGeog->_isEquivalentTo(
+                 geogDst, util::IComparable::Criterion::EQUIVALENT) ||
+             hubSrcGeog->is2DPartOf3D(NN_NO_CHECK(geogDst)))) {
+            if (boundSrc->baseCRS() == geogCRSOfBaseOfBoundSrc) {
+                // Optimization to avoid creating a useless concatenated
+                // operation
+                res.emplace_back(boundSrc->transformation());
+                return res;
+            }
+            auto opsFirst =
+                createOperations(boundSrc->baseCRS(),
+                                 NN_NO_CHECK(geogCRSOfBaseOfBoundSrc), context);
+            if (!opsFirst.empty()) {
+                for (const auto &opFirst : opsFirst) {
+                    try {
+                        res.emplace_back(
+                            ConcatenatedOperation::createComputeMetadata(
+                                {opFirst, boundSrc->transformation()},
+                                !allowEmptyIntersection));
+                    } catch (const InvalidOperationEmptyIntersection &) {
+                    }
+                }
+                if (!res.empty()) {
+                    return res;
+                }
+            }
+            // If the datum are equivalent, this is also fine
+        } else if (geogCRSOfBaseOfBoundSrc && hubSrcGeog->datum() &&
+                   geogDst->datum() &&
+                   hubSrcGeog->datum()->_isEquivalentTo(
+                       geogDst->datum().get(),
+                       util::IComparable::Criterion::EQUIVALENT)) {
+            auto opsFirst =
+                createOperations(boundSrc->baseCRS(),
+                                 NN_NO_CHECK(geogCRSOfBaseOfBoundSrc), context);
+            auto opsLast = createOperations(hubSrc, targetCRS, context);
+            if (!opsFirst.empty() && !opsLast.empty()) {
+                for (const auto &opFirst : opsFirst) {
+                    for (const auto &opLast : opsLast) {
+                        try {
+                            res.emplace_back(
+                                ConcatenatedOperation::createComputeMetadata(
+                                    {opFirst, boundSrc->transformation(),
+                                     opLast},
+                                    !allowEmptyIntersection));
+                        } catch (const InvalidOperationEmptyIntersection &) {
+                        }
+                    }
+                }
+                if (!res.empty()) {
+                    return res;
+                }
+            }
+            // Consider WGS 84 and NAD83 as equivalent in that context if the
+            // geogCRSOfBaseOfBoundSrc ellipsoid is Clarke66 (for NAD27)
+            // Case of "+proj=latlong +ellps=clrk66
+            // +nadgrids=ntv1_can.dat,conus"
+            // to "+proj=latlong +datum=NAD83"
+        } else if (geogCRSOfBaseOfBoundSrc && hubSrcGeog->datum() &&
+                   geogDst->datum() &&
+                   geogCRSOfBaseOfBoundSrc->ellipsoid()->_isEquivalentTo(
+                       datum::Ellipsoid::CLARKE_1866.get(),
+                       util::IComparable::Criterion::EQUIVALENT) &&
+                   hubSrcGeog->datum()->_isEquivalentTo(
+                       datum::GeodeticReferenceFrame::EPSG_6326.get(),
+                       util::IComparable::Criterion::EQUIVALENT) &&
+                   geogDst->datum()->_isEquivalentTo(
+                       datum::GeodeticReferenceFrame::EPSG_6269.get(),
+                       util::IComparable::Criterion::EQUIVALENT)) {
+            auto nnGeogCRSOfBaseOfBoundSrc =
+                NN_NO_CHECK(geogCRSOfBaseOfBoundSrc);
+            if (boundSrc->baseCRS()->_isEquivalentTo(
+                    nnGeogCRSOfBaseOfBoundSrc.get(),
+                    util::IComparable::Criterion::EQUIVALENT)) {
+                auto transf = boundSrc->transformation()->shallowClone();
+                transf->setProperties(util::PropertyMap().set(
+                    common::IdentifiedObject::NAME_KEY,
+                    buildTransfName(boundSrc->baseCRS()->nameStr(),
+                                    targetCRS->nameStr())));
+                transf->setCRSs(boundSrc->baseCRS(), targetCRS, nullptr);
+                res.emplace_back(transf);
+                return res;
+            } else {
+                auto opsFirst = createOperations(
+                    boundSrc->baseCRS(), nnGeogCRSOfBaseOfBoundSrc, context);
+                auto transf = boundSrc->transformation()->shallowClone();
+                transf->setProperties(util::PropertyMap().set(
+                    common::IdentifiedObject::NAME_KEY,
+                    buildTransfName(nnGeogCRSOfBaseOfBoundSrc->nameStr(),
+                                    targetCRS->nameStr())));
+                transf->setCRSs(nnGeogCRSOfBaseOfBoundSrc, targetCRS, nullptr);
+                if (!opsFirst.empty()) {
+                    for (const auto &opFirst : opsFirst) {
+                        try {
+                            res.emplace_back(
+                                ConcatenatedOperation::createComputeMetadata(
+                                    {opFirst, transf},
+                                    !allowEmptyIntersection));
+                        } catch (const InvalidOperationEmptyIntersection &) {
+                        }
+                    }
+                    if (!res.empty()) {
+                        return res;
+                    }
+                }
+            }
+        }
+
+        if (hubSrcGeog &&
+            hubSrcGeog->_isEquivalentTo(
+                geogDst, util::IComparable::Criterion::EQUIVALENT) &&
+            dynamic_cast<const crs::VerticalCRS *>(boundSrc->baseCRS().get())) {
+            res.emplace_back(boundSrc->transformation());
+            return res;
+        }
+
+        return createOperations(boundSrc->baseCRS(), targetCRS, context);
+    }
+
+    // reverse of previous case
+    auto boundDst = dynamic_cast<const crs::BoundCRS *>(targetCRS.get());
+    auto geogSrc = dynamic_cast<const crs::GeographicCRS *>(sourceCRS.get());
+    if (geogSrc && boundDst) {
+        return applyInverse(createOperations(targetCRS, sourceCRS, context));
+    }
+
+    // vertCRS (as boundCRS with transformation to target vertCRS) to
+    // vertCRS
+    auto vertDst = dynamic_cast<const crs::VerticalCRS *>(targetCRS.get());
+    if (boundSrc && vertDst) {
+        auto baseSrcVert =
+            dynamic_cast<const crs::VerticalCRS *>(boundSrc->baseCRS().get());
+        const auto &hubSrc = boundSrc->hubCRS();
+        auto hubSrcVert = dynamic_cast<const crs::VerticalCRS *>(hubSrc.get());
+        if (baseSrcVert && hubSrcVert &&
+            vertDst->_isEquivalentTo(
+                hubSrcVert, util::IComparable::Criterion::EQUIVALENT)) {
+            res.emplace_back(boundSrc->transformation());
+            return res;
+        }
+
+        return createOperations(boundSrc->baseCRS(), targetCRS, context);
+    }
+
+    // reverse of previous case
+    auto vertSrc = dynamic_cast<const crs::VerticalCRS *>(sourceCRS.get());
+    if (boundDst && vertSrc) {
+        return applyInverse(createOperations(targetCRS, sourceCRS, context));
+    }
+
+    if (vertSrc && vertDst) {
+        const auto &srcDatum = vertSrc->datum();
+        const auto &dstDatum = vertDst->datum();
+        if (srcDatum && dstDatum &&
+            srcDatum->_isEquivalentTo(
+                dstDatum.get(), util::IComparable::Criterion::EQUIVALENT)) {
+            const double convSrc = vertSrc->coordinateSystem()
+                                       ->axisList()[0]
+                                       ->unit()
+                                       .conversionToSI();
+            const double convDst = vertDst->coordinateSystem()
+                                       ->axisList()[0]
+                                       ->unit()
+                                       .conversionToSI();
+            if (convSrc != convDst) {
+                const double factor = convSrc / convDst;
+                auto conv = Conversion::createChangeVerticalUnit(
+                    util::PropertyMap().set(
+                        common::IdentifiedObject::NAME_KEY,
+                        buildTransfName(sourceCRS->nameStr(),
+                                        targetCRS->nameStr())),
+                    common::Scale(factor));
+                conv->setCRSs(sourceCRS, targetCRS, nullptr);
+                res.push_back(conv);
+                return res;
+            }
+        }
+    }
+
+    // A bit odd case as we are comparing apples to oranges, but in case
+    // the vertical unit differ, do something useful.
+    if (vertSrc && geogDst) {
+        const double convSrc =
+            vertSrc->coordinateSystem()->axisList()[0]->unit().conversionToSI();
+        double convDst = 1.0;
+        const auto &geogAxis = geogDst->coordinateSystem()->axisList();
+        if (geogAxis.size() == 3) {
+            convDst = geogAxis[2]->unit().conversionToSI();
+        }
+        if (convSrc != convDst) {
+            const double factor = convSrc / convDst;
+            auto conv = Conversion::createChangeVerticalUnit(
+                util::PropertyMap().set(common::IdentifiedObject::NAME_KEY,
+                                        buildTransfName(sourceCRS->nameStr(),
+                                                        targetCRS->nameStr())),
+                common::Scale(factor));
+            conv->setCRSs(sourceCRS, targetCRS, nullptr);
+            res.push_back(conv);
+            return res;
+        }
+    }
+
+    // reverse of previous case
+    if (vertDst && geogSrc) {
+        return applyInverse(createOperations(targetCRS, sourceCRS, context));
+    }
+
+    // boundCRS to boundCRS using the same geographic hubCRS
+    if (boundSrc && boundDst) {
+        const auto &hubSrc = boundSrc->hubCRS();
+        auto hubSrcGeog =
+            dynamic_cast<const crs::GeographicCRS *>(hubSrc.get());
+        const auto &hubDst = boundDst->hubCRS();
+        auto hubDstGeog =
+            dynamic_cast<const crs::GeographicCRS *>(hubDst.get());
+        auto geogCRSOfBaseOfBoundSrc =
+            boundSrc->baseCRS()->extractGeographicCRS();
+        auto geogCRSOfBaseOfBoundDst =
+            boundDst->baseCRS()->extractGeographicCRS();
+        if (hubSrcGeog && hubDstGeog &&
+            hubSrcGeog->_isEquivalentTo(
+                hubDstGeog, util::IComparable::Criterion::EQUIVALENT) &&
+            geogCRSOfBaseOfBoundSrc && geogCRSOfBaseOfBoundDst) {
+            const bool firstIsNoOp = geogCRSOfBaseOfBoundSrc->_isEquivalentTo(
+                boundSrc->baseCRS().get(),
+                util::IComparable::Criterion::EQUIVALENT);
+            const bool lastIsNoOp = geogCRSOfBaseOfBoundDst->_isEquivalentTo(
+                boundDst->baseCRS().get(),
+                util::IComparable::Criterion::EQUIVALENT);
+            auto opsFirst =
+                createOperations(boundSrc->baseCRS(),
+                                 NN_NO_CHECK(geogCRSOfBaseOfBoundSrc), context);
+            auto opsLast =
+                createOperations(NN_NO_CHECK(geogCRSOfBaseOfBoundDst),
+                                 boundDst->baseCRS(), context);
+            if (!opsFirst.empty() && !opsLast.empty()) {
+                const auto &opSecond = boundSrc->transformation();
+                auto opThird = boundDst->transformation()->inverse();
+                for (const auto &opFirst : opsFirst) {
+                    for (const auto &opLast : opsLast) {
+                        try {
+                            std::vector<CoordinateOperationNNPtr> ops;
+                            if (!firstIsNoOp) {
+                                ops.push_back(opFirst);
+                            }
+                            ops.push_back(opSecond);
+                            ops.push_back(opThird);
+                            if (!lastIsNoOp) {
+                                ops.push_back(opLast);
+                            }
+                            res.emplace_back(
+                                ConcatenatedOperation::createComputeMetadata(
+                                    ops, !allowEmptyIntersection));
+                        } catch (const InvalidOperationEmptyIntersection &) {
+                        }
+                    }
+                }
+                if (!res.empty()) {
+                    return res;
+                }
+            }
+        }
+
+        return createOperations(boundSrc->baseCRS(), boundDst->baseCRS(),
+                                context);
+    }
+
+    auto compoundSrc = dynamic_cast<crs::CompoundCRS *>(sourceCRS.get());
+    if (compoundSrc && geogDst) {
+        const auto &componentsSrc = compoundSrc->componentReferenceSystems();
+        if (!componentsSrc.empty()) {
+            std::vector<CoordinateOperationNNPtr> horizTransforms;
+            if (componentsSrc[0]->extractGeographicCRS()) {
+                horizTransforms =
+                    createOperations(componentsSrc[0], targetCRS, context);
+            }
+            std::vector<CoordinateOperationNNPtr> verticalTransforms;
+            if (componentsSrc.size() >= 2 &&
+                componentsSrc[1]->extractVerticalCRS()) {
+                verticalTransforms =
+                    createOperations(componentsSrc[1], targetCRS, context);
+            }
+            if (!horizTransforms.empty() && !verticalTransforms.empty()) {
+                for (const auto &horizTransform : horizTransforms) {
+                    for (const auto &verticalTransform : verticalTransforms) {
+
+                        auto op = createHorizVerticalPROJBased(
+                            sourceCRS, targetCRS, horizTransform,
+                            verticalTransform);
+
+                        res.emplace_back(op);
+                    }
+                }
+                return res;
+            } else {
+                return horizTransforms;
+            }
+        }
+    }
+
+    // reverse of previous case
+    auto compoundDst = dynamic_cast<const crs::CompoundCRS *>(targetCRS.get());
+    if (geogSrc && compoundDst) {
+        return applyInverse(createOperations(targetCRS, sourceCRS, context));
+    }
+
+    if (compoundSrc && compoundDst) {
+        const auto &componentsSrc = compoundSrc->componentReferenceSystems();
+        const auto &componentsDst = compoundDst->componentReferenceSystems();
+        if (!componentsSrc.empty() &&
+            componentsSrc.size() == componentsDst.size()) {
+            if (componentsSrc[0]->extractGeographicCRS() &&
+                componentsDst[0]->extractGeographicCRS()) {
+
+                std::vector<CoordinateOperationNNPtr> verticalTransforms;
+                if (componentsSrc.size() >= 2 &&
+                    componentsSrc[1]->extractVerticalCRS() &&
+                    componentsDst[1]->extractVerticalCRS()) {
+                    verticalTransforms = createOperations(
+                        componentsSrc[1], componentsDst[1], context);
+                }
+
+                for (const auto &verticalTransform : verticalTransforms) {
+                    auto interpolationGeogCRS =
+                        NN_NO_CHECK(componentsSrc[0]->extractGeographicCRS());
+                    auto transformationVerticalTransform =
+                        dynamic_cast<const Transformation *>(
+                            verticalTransform.get());
+                    if (transformationVerticalTransform) {
+                        auto interpTransformCRS =
+                            transformationVerticalTransform->interpolationCRS();
+                        if (interpTransformCRS) {
+                            auto nn_interpTransformCRS =
+                                NN_NO_CHECK(interpTransformCRS);
+                            if (dynamic_cast<const crs::GeographicCRS *>(
+                                    nn_interpTransformCRS.get())) {
+                                interpolationGeogCRS =
+                                    NN_NO_CHECK(util::nn_dynamic_pointer_cast<
+                                                crs::GeographicCRS>(
+                                        nn_interpTransformCRS));
+                            }
+                        }
+                    }
+                    auto opSrcCRSToGeogCRS = createOperations(
+                        componentsSrc[0], interpolationGeogCRS, context);
+                    auto opGeogCRStoDstCRS = createOperations(
+                        interpolationGeogCRS, componentsDst[0], context);
+                    for (const auto &opSrc : opSrcCRSToGeogCRS) {
+                        for (const auto &opDst : opGeogCRStoDstCRS) {
+
+                            auto op = createHorizVerticalHorizPROJBased(
+                                sourceCRS, targetCRS, opSrc, verticalTransform,
+                                opDst, interpolationGeogCRS);
+                            res.emplace_back(op);
+                        }
+                    }
+                }
+
+                if (verticalTransforms.empty()) {
+                    return createOperations(componentsSrc[0], componentsDst[0],
+                                            context);
+                }
+            }
+        }
+    }
+
+    return res;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Find a list of CoordinateOperation from sourceCRS to targetCRS.
+ *
+ * The operations are sorted with the most relevant ones first: by
+ * descending
+ * area (intersection of the transformation area with the area of interest,
+ * or intersection of the transformation with the area of use of the CRS),
+ * and
+ * by increasing accuracy. Operations with unknown accuracy are sorted last,
+ * whatever their area.
+ *
+ * @param sourceCRS source CRS.
+ * @param targetCRS source CRS.
+ * @param context Search context.
+ * @return a list
+ */
+std::vector<CoordinateOperationNNPtr>
+CoordinateOperationFactory::createOperations(
+    const crs::CRSNNPtr &sourceCRS, const crs::CRSNNPtr &targetCRS,
+    const CoordinateOperationContextNNPtr &context) const {
+
+    // Look if we are called on CRS that have a link to a 'canonical'
+    // BoundCRS
+    // If so, use that one as input
+    const auto &srcBoundCRS = sourceCRS->canonicalBoundCRS();
+    const auto &targetBoundCRS = targetCRS->canonicalBoundCRS();
+    auto l_sourceCRS = srcBoundCRS ? NN_NO_CHECK(srcBoundCRS) : sourceCRS;
+    auto l_targetCRS = targetBoundCRS ? NN_NO_CHECK(targetBoundCRS) : targetCRS;
+
+    Private::Context contextPrivate(sourceCRS, targetCRS, context);
+    return filterAndSort(
+        Private::createOperations(l_sourceCRS, l_targetCRS, contextPrivate),
+        context, l_sourceCRS, l_targetCRS);
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a CoordinateOperationFactory.
+ */
+CoordinateOperationFactoryNNPtr CoordinateOperationFactory::create() {
+    return NN_NO_CHECK(
+        CoordinateOperationFactory::make_unique<CoordinateOperationFactory>());
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+InverseCoordinateOperation::~InverseCoordinateOperation() = default;
+
+// ---------------------------------------------------------------------------
+
+InverseCoordinateOperation::InverseCoordinateOperation(
+    const CoordinateOperationNNPtr &forwardOperation, bool wktSupportsInversion)
+    : forwardOperation_(forwardOperation),
+      wktSupportsInversion_(wktSupportsInversion) {}
+
+// ---------------------------------------------------------------------------
+
+void InverseCoordinateOperation::setPropertiesFromForward() {
+    setProperties(
+        createPropertiesForInverse(forwardOperation_.get(), false, false));
+    setAccuracies(forwardOperation_->coordinateOperationAccuracies());
+    if (forwardOperation_->sourceCRS() && forwardOperation_->targetCRS()) {
+        setCRSs(forwardOperation_.get(), true);
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+CoordinateOperationNNPtr InverseCoordinateOperation::inverse() const {
+    return forwardOperation_;
+}
+
+// ---------------------------------------------------------------------------
+
+void InverseCoordinateOperation::_exportToPROJString(
+    io::PROJStringFormatter *formatter) const {
+    formatter->startInversion();
+    forwardOperation_->_exportToPROJString(formatter);
+    formatter->stopInversion();
+}
+
+// ---------------------------------------------------------------------------
+
+bool InverseCoordinateOperation::_isEquivalentTo(
+    const util::IComparable *other,
+    util::IComparable::Criterion criterion) const {
+    auto otherICO = dynamic_cast<const InverseCoordinateOperation *>(other);
+    if (otherICO == nullptr ||
+        !ObjectUsage::_isEquivalentTo(other, criterion)) {
+        return false;
+    }
+    return inverse()->_isEquivalentTo(otherICO->inverse().get(), criterion);
+}
+
+// ---------------------------------------------------------------------------
+
+PROJBasedOperation::~PROJBasedOperation() = default;
+
+// ---------------------------------------------------------------------------
+
+PROJBasedOperation::PROJBasedOperation(
+    const OperationMethodNNPtr &methodIn,
+    const std::vector<GeneralParameterValueNNPtr> &values)
+    : SingleOperation(methodIn) {
+    setParameterValues(values);
+}
+
+// ---------------------------------------------------------------------------
+
+static const std::string PROJSTRING_PARAMETER_NAME("PROJ string");
+
+PROJBasedOperationNNPtr PROJBasedOperation::create(
+    const util::PropertyMap &properties, const std::string &PROJString,
+    const crs::CRSPtr &sourceCRS, const crs::CRSPtr &targetCRS,
+    const std::vector<metadata::PositionalAccuracyNNPtr> &accuracies) {
+    auto parameter = OperationParameter::create(util::PropertyMap().set(
+        common::IdentifiedObject::NAME_KEY, PROJSTRING_PARAMETER_NAME));
+    auto method = OperationMethod::create(
+        util::PropertyMap().set(common::IdentifiedObject::NAME_KEY,
+                                "PROJ-based operation method"),
+        std::vector<OperationParameterNNPtr>{parameter});
+    std::vector<GeneralParameterValueNNPtr> values;
+    values.push_back(OperationParameterValue::create(
+        parameter, ParameterValue::create(PROJString)));
+    auto op =
+        PROJBasedOperation::nn_make_shared<PROJBasedOperation>(method, values);
+    op->assignSelf(op);
+    if (sourceCRS && targetCRS) {
+        op->setCRSs(NN_NO_CHECK(sourceCRS), NN_NO_CHECK(targetCRS), nullptr);
+    }
+    op->setProperties(
+        addDefaultNameIfNeeded(properties, "PROJ-based coordinate operation"));
+    op->setAccuracies(accuracies);
+    return op;
+}
+
+// ---------------------------------------------------------------------------
+
+static const std::string
+    APPROX_PROJSTRING_PARAMETER_NAME("(Approximte) PROJ string");
+
+PROJBasedOperationNNPtr PROJBasedOperation::create(
+    const util::PropertyMap &properties,
+    const io::IPROJStringExportableNNPtr &projExportable, bool inverse,
+    const crs::CRSNNPtr &sourceCRS, const crs::CRSNNPtr &targetCRS,
+    const std::vector<metadata::PositionalAccuracyNNPtr> &accuracies) {
+    auto parameter = OperationParameter::create(util::PropertyMap().set(
+        common::IdentifiedObject::NAME_KEY, APPROX_PROJSTRING_PARAMETER_NAME));
+    auto method = OperationMethod::create(
+        util::PropertyMap().set(common::IdentifiedObject::NAME_KEY,
+                                "PROJ-based operation method"),
+        std::vector<OperationParameterNNPtr>{parameter});
+    std::vector<GeneralParameterValueNNPtr> values;
+
+    auto formatter = io::PROJStringFormatter::create();
+    if (inverse) {
+        formatter->startInversion();
+    }
+    projExportable->_exportToPROJString(formatter.get());
+    if (inverse) {
+        formatter->stopInversion();
+    }
+    auto projString = formatter->toString();
+
+    values.push_back(OperationParameterValue::create(
+        parameter, ParameterValue::create(projString)));
+    auto op =
+        PROJBasedOperation::nn_make_shared<PROJBasedOperation>(method, values);
+    op->assignSelf(op);
+    op->setCRSs(sourceCRS, targetCRS, nullptr);
+    op->setProperties(
+        addDefaultNameIfNeeded(properties, "PROJ-based coordinate operation"));
+    op->setAccuracies(accuracies);
+    op->projStringExportable_ = projExportable.as_nullable();
+    op->inverse_ = inverse;
+    return op;
+}
+
+// ---------------------------------------------------------------------------
+
+CoordinateOperationNNPtr PROJBasedOperation::inverse() const {
+
+    if (projStringExportable_) {
+        return util::nn_static_pointer_cast<CoordinateOperation>(
+            PROJBasedOperation::create(
+                createPropertiesForInverse(this, false, false),
+                NN_NO_CHECK(projStringExportable_), !inverse_,
+                NN_NO_CHECK(targetCRS()), NN_NO_CHECK(sourceCRS()),
+                coordinateOperationAccuracies()));
+    }
+
+    auto formatter = io::PROJStringFormatter::create();
+    formatter->startInversion();
+    try {
+        formatter->ingestPROJString(
+            parameterValue(PROJSTRING_PARAMETER_NAME)->stringValue());
+    } catch (const io::ParsingException &e) {
+        throw util::UnsupportedOperationException(
+            std::string("PROJBasedOperation::inverse() failed: ") + e.what());
+    }
+    formatter->stopInversion();
+
+    return util::nn_static_pointer_cast<CoordinateOperation>(
+        PROJBasedOperation::create(
+            createPropertiesForInverse(this, false, false),
+            formatter->toString(), targetCRS(), sourceCRS(),
+            coordinateOperationAccuracies()));
+}
+
+// ---------------------------------------------------------------------------
+
+void PROJBasedOperation::_exportToWKT(io::WKTFormatter *formatter) const {
+
+    if (sourceCRS() && targetCRS()) {
+        exportTransformationToWKT(formatter);
+        return;
+    }
+
+    const bool isWKT2 = formatter->version() == io::WKTFormatter::Version::WKT2;
+    if (!isWKT2) {
+        throw io::FormattingException(
+            "PROJBasedOperation can only be exported to WKT2");
+    }
+
+    formatter->startNode(io::WKTConstants::CONVERSION, false);
+    formatter->addQuotedString(nameStr());
+    method()->_exportToWKT(formatter);
+
+    for (const auto &paramValue : parameterValues()) {
+        paramValue->_exportToWKT(formatter);
+    }
+    formatter->endNode();
+}
+
+// ---------------------------------------------------------------------------
+
+void PROJBasedOperation::_exportToPROJString(
+    io::PROJStringFormatter *formatter) const {
+    if (projStringExportable_) {
+        if (inverse_) {
+            formatter->startInversion();
+        }
+        projStringExportable_->_exportToPROJString(formatter);
+        if (inverse_) {
+            formatter->stopInversion();
+        }
+        return;
+    }
+
+    try {
+        formatter->ingestPROJString(
+            parameterValue(PROJSTRING_PARAMETER_NAME)->stringValue());
+    } catch (const io::ParsingException &e) {
+        throw io::FormattingException(
+            std::string("PROJBasedOperation::exportToPROJString() failed: ") +
+            e.what());
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+std::set<GridDescription> PROJBasedOperation::gridsNeeded(
+    const io::DatabaseContextPtr &databaseContext) const {
+    std::set<GridDescription> res;
+
+    try {
+        auto formatterOut = io::PROJStringFormatter::create();
+        auto formatter = io::PROJStringFormatter::create();
+        formatter->ingestPROJString(exportToPROJString(formatterOut.get()));
+        const auto usedGridNames = formatter->getUsedGridNames();
+        for (const auto &shortName : usedGridNames) {
+            GridDescription desc;
+            desc.shortName = shortName;
+            if (databaseContext) {
+                databaseContext->lookForGridInfo(
+                    desc.shortName, desc.fullName, desc.packageName, desc.url,
+                    desc.directDownload, desc.openLicense, desc.available);
+            }
+            res.insert(desc);
+        }
+    } catch (const io::ParsingException &) {
+    }
+
+    return res;
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+} // namespace operation
+NS_PROJ_END
diff --git a/src/iso19111/coordinatesystem.cpp b/src/iso19111/coordinatesystem.cpp
new file mode 100644
index 00000000..a3ad04e0
--- /dev/null
+++ b/src/iso19111/coordinatesystem.cpp
@@ -0,0 +1,1279 @@
+/******************************************************************************
+ *
+ * Project:  PROJ
+ * Purpose:  ISO19111:2018 implementation
+ * Author:   Even Rouault <even dot rouault at spatialys dot com>
+ *
+ ******************************************************************************
+ * Copyright (c) 2018, Even Rouault <even dot rouault at spatialys dot com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ ****************************************************************************/
+
+#ifndef FROM_PROJ_CPP
+#define FROM_PROJ_CPP
+#endif
+
+#include "proj/coordinatesystem.hpp"
+#include "proj/common.hpp"
+#include "proj/io.hpp"
+#include "proj/metadata.hpp"
+#include "proj/util.hpp"
+
+#include "proj/internal/coordinatesystem_internal.hpp"
+#include "proj/internal/internal.hpp"
+#include "proj/internal/io_internal.hpp"
+
+#include <map>
+#include <memory>
+#include <set>
+#include <string>
+#include <vector>
+
+using namespace NS_PROJ::internal;
+
+#if 0
+namespace dropbox{ namespace oxygen {
+template<> nn<NS_PROJ::cs::MeridianPtr>::~nn() = default;
+template<> nn<NS_PROJ::cs::CoordinateSystemAxisPtr>::~nn() = default;
+template<> nn<NS_PROJ::cs::CoordinateSystemPtr>::~nn() = default;
+template<> nn<NS_PROJ::cs::SphericalCSPtr>::~nn() = default;
+template<> nn<NS_PROJ::cs::EllipsoidalCSPtr>::~nn() = default;
+template<> nn<NS_PROJ::cs::CartesianCSPtr>::~nn() = default;
+template<> nn<NS_PROJ::cs::TemporalCSPtr>::~nn() = default;
+template<> nn<NS_PROJ::cs::TemporalCountCSPtr>::~nn() = default;
+template<> nn<NS_PROJ::cs::TemporalMeasureCSPtr>::~nn() = default;
+template<> nn<NS_PROJ::cs::DateTimeTemporalCSPtr>::~nn() = default;
+template<> nn<NS_PROJ::cs::VerticalCSPtr>::~nn() = default;
+template<> nn<NS_PROJ::cs::ParametricCSPtr>::~nn() = default;
+template<> nn<NS_PROJ::cs::OrdinalCSPtr>::~nn() = default;
+}}
+#endif
+
+NS_PROJ_START
+namespace cs {
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct Meridian::Private {
+    common::Angle longitude_{};
+
+    explicit Private(const common::Angle &longitude) : longitude_(longitude) {}
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+Meridian::Meridian(const common::Angle &longitudeIn)
+    : d(internal::make_unique<Private>(longitudeIn)) {}
+
+// ---------------------------------------------------------------------------
+
+#ifdef notdef
+Meridian::Meridian(const Meridian &other)
+    : IdentifiedObject(other), d(internal::make_unique<Private>(*other.d)) {}
+#endif
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+Meridian::~Meridian() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the longitude of the meridian that the axis follows from the
+ * pole.
+ *
+ * @return the longitude.
+ */
+const common::Angle &Meridian::longitude() PROJ_CONST_DEFN {
+    return d->longitude_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a Meridian.
+ *
+ * @param longitudeIn longitude of the meridian that the axis follows from the
+ * pole.
+ * @return new Meridian.
+ */
+MeridianNNPtr Meridian::create(const common::Angle &longitudeIn) {
+    return Meridian::nn_make_shared<Meridian>(longitudeIn);
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void Meridian::_exportToWKT(
+    io::WKTFormatter *formatter) const // throw(FormattingException)
+{
+    formatter->startNode(io::WKTConstants::MERIDIAN, !identifiers().empty());
+    formatter->add(longitude().value());
+    longitude().unit()._exportToWKT(formatter, io::WKTConstants::ANGLEUNIT);
+    if (formatter->outputId()) {
+        formatID(formatter);
+    }
+    formatter->endNode();
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct CoordinateSystemAxis::Private {
+    std::string abbreviation{};
+    const AxisDirection *direction = &(AxisDirection::UNSPECIFIED);
+    common::UnitOfMeasure unit{};
+    util::optional<double> minimumValue{};
+    util::optional<double> maximumValue{};
+    MeridianPtr meridian{};
+    // TODO rangeMeaning
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+CoordinateSystemAxis::CoordinateSystemAxis()
+    : d(internal::make_unique<Private>()) {}
+
+// ---------------------------------------------------------------------------
+
+#ifdef notdef
+CoordinateSystemAxis::CoordinateSystemAxis(const CoordinateSystemAxis &other)
+    : IdentifiedObject(other), d(internal::make_unique<Private>(*other.d)) {}
+#endif
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+CoordinateSystemAxis::~CoordinateSystemAxis() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the axis abbreviation.
+ *
+ * The abbreviation used for this coordinate system axis; this abbreviation
+ * is also used to identify the coordinates in the coordinate tuple.
+ * Examples are X and Y.
+ *
+ * @return the abbreviation.
+ */
+const std::string &CoordinateSystemAxis::abbreviation() PROJ_CONST_DEFN {
+    return d->abbreviation;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the axis direction.
+ *
+ * The direction of this coordinate system axis (or in the case of Cartesian
+ * projected coordinates, the direction of this coordinate system axis locally)
+ * Examples: north or south, east or west, up or down. Within any set of
+ * coordinate system axes, only one of each pair of terms can be used. For
+ * Earth-fixed CRSs, this direction is often approximate and intended to
+ * provide a human interpretable meaning to the axis. When a geodetic reference
+ * frame is used, the precise directions of the axes may therefore vary
+ * slightly from this approximate direction. Note that an EngineeringCRS often
+ * requires specific descriptions of the directions of its coordinate system
+ * axes.
+ *
+ * @return the direction.
+ */
+const AxisDirection &CoordinateSystemAxis::direction() PROJ_CONST_DEFN {
+    return *(d->direction);
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the axis unit.
+ *
+ * This is the spatial unit or temporal quantity used for this coordinate
+ * system axis. The value of a coordinate in a coordinate tuple shall be
+ * recorded using this unit.
+ *
+ * @return the axis unit.
+ */
+const common::UnitOfMeasure &CoordinateSystemAxis::unit() PROJ_CONST_DEFN {
+    return d->unit;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the minimum value normally allowed for this axis, in the unit
+ * for the axis.
+ *
+ * @return the minimum value, or empty.
+ */
+const util::optional<double> &
+CoordinateSystemAxis::minimumValue() PROJ_CONST_DEFN {
+    return d->minimumValue;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the maximum value normally allowed for this axis, in the unit
+ * for the axis.
+ *
+ * @return the maximum value, or empty.
+ */
+const util::optional<double> &
+CoordinateSystemAxis::maximumValue() PROJ_CONST_DEFN {
+    return d->maximumValue;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the meridian that the axis follows from the pole, for a
+ * coordinate
+ * reference system centered on a pole.
+ *
+ * @return the meridian, or null.
+ */
+const MeridianPtr &CoordinateSystemAxis::meridian() PROJ_CONST_DEFN {
+    return d->meridian;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a CoordinateSystemAxis.
+ *
+ * @param properties See \ref general_properties. The name should generally be
+ * defined.
+ * @param abbreviationIn Axis abbreviation (might be empty)
+ * @param directionIn Axis direction
+ * @param unitIn Axis unit
+ * @param meridianIn The meridian that the axis follows from the pole, for a
+ * coordinate
+ * reference system centered on a pole, or nullptr
+ * @return a new CoordinateSystemAxis.
+ */
+CoordinateSystemAxisNNPtr CoordinateSystemAxis::create(
+    const util::PropertyMap &properties, const std::string &abbreviationIn,
+    const AxisDirection &directionIn, const common::UnitOfMeasure &unitIn,
+    const MeridianPtr &meridianIn) {
+    auto csa(CoordinateSystemAxis::nn_make_shared<CoordinateSystemAxis>());
+    csa->setProperties(properties);
+    csa->d->abbreviation = abbreviationIn;
+    csa->d->direction = &directionIn;
+    csa->d->unit = unitIn;
+    csa->d->meridian = meridianIn;
+    return csa;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void CoordinateSystemAxis::_exportToWKT(
+    // cppcheck-suppress passedByValue
+    io::WKTFormatter *formatter) const // throw(FormattingException)
+{
+    _exportToWKT(formatter, 0, false);
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+std::string CoordinateSystemAxis::normalizeAxisName(const std::string &str) {
+    if (str.empty()) {
+        return str;
+    }
+    // on import, transform from WKT2 "longitude" to "Longitude", as in the
+    // EPSG database.
+    return toupper(str.substr(0, 1)) + str.substr(1);
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void CoordinateSystemAxis::_exportToWKT(io::WKTFormatter *formatter, int order,
+                                        bool disableAbbrev) const {
+    const bool isWKT2 = formatter->version() == io::WKTFormatter::Version::WKT2;
+    formatter->startNode(io::WKTConstants::AXIS, !identifiers().empty());
+    std::string axisName = *(name()->description());
+    std::string abbrev = abbreviation();
+    std::string parenthesedAbbrev = "(" + abbrev + ")";
+    std::string dir = direction().toString();
+    std::string axisDesignation;
+
+    // It seems that the convention in WKT2 for axis name is first letter in
+    // lower case. Whereas in WKT1 GDAL, it is in upper case (as in the EPSG
+    // database)
+    if (!axisName.empty()) {
+        if (isWKT2) {
+            axisDesignation =
+                tolower(axisName.substr(0, 1)) + axisName.substr(1);
+        } else {
+            if (axisName == "Geodetic latitude") {
+                axisDesignation = "Latitude";
+            } else if (axisName == "Geodetic longitude") {
+                axisDesignation = "Longitude";
+            } else {
+                axisDesignation = axisName;
+            }
+        }
+    }
+
+    if (!disableAbbrev && isWKT2 &&
+        // For geodetic CS, export the axis name without abbreviation
+        !(axisName == AxisName::Latitude || axisName == AxisName::Longitude)) {
+        if (!axisDesignation.empty() && !abbrev.empty()) {
+            axisDesignation += " ";
+        }
+        if (!abbrev.empty()) {
+            axisDesignation += parenthesedAbbrev;
+        }
+    }
+    if (!isWKT2) {
+        dir = toupper(dir);
+
+        if (direction() == AxisDirection::GEOCENTRIC_Z) {
+            dir = AxisDirectionWKT1::NORTH;
+        } else if (AxisDirectionWKT1::valueOf(dir) == nullptr) {
+            dir = AxisDirectionWKT1::OTHER;
+        }
+    } else if (!abbrev.empty()) {
+        // For geocentric CS, just put the abbreviation
+        if (direction() == AxisDirection::GEOCENTRIC_X ||
+            direction() == AxisDirection::GEOCENTRIC_Y ||
+            direction() == AxisDirection::GEOCENTRIC_Z) {
+            axisDesignation = parenthesedAbbrev;
+        }
+        // For cartesian CS with Easting/Northing, export only the abbreviation
+        else if ((order == 1 && axisName == AxisName::Easting &&
+                  abbrev == AxisAbbreviation::E) ||
+                 (order == 2 && axisName == AxisName::Northing &&
+                  abbrev == AxisAbbreviation::N)) {
+            axisDesignation = parenthesedAbbrev;
+        }
+    }
+    formatter->addQuotedString(axisDesignation);
+    formatter->add(dir);
+    const auto &l_meridian = meridian();
+    if (isWKT2 && l_meridian) {
+        l_meridian->_exportToWKT(formatter);
+    }
+    if (formatter->outputAxisOrder() && order > 0) {
+        formatter->startNode(io::WKTConstants::ORDER, false);
+        formatter->add(order);
+        formatter->endNode();
+    }
+    if (formatter->outputUnit() &&
+        unit().type() != common::UnitOfMeasure::Type::NONE) {
+        unit()._exportToWKT(formatter);
+    }
+    if (formatter->outputId()) {
+        formatID(formatter);
+    }
+    formatter->endNode();
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+bool CoordinateSystemAxis::_isEquivalentTo(
+    const util::IComparable *other,
+    util::IComparable::Criterion criterion) const {
+    auto otherCSA = dynamic_cast<const CoordinateSystemAxis *>(other);
+    if (otherCSA == nullptr) {
+        return false;
+    }
+    // For approximate comparison, only care about axis direction and unit.
+    if (!(*(d->direction) == *(otherCSA->d->direction) &&
+          d->unit._isEquivalentTo(otherCSA->d->unit, criterion))) {
+        return false;
+    }
+    if (criterion == util::IComparable::Criterion::STRICT) {
+        if (!IdentifiedObject::_isEquivalentTo(other, criterion)) {
+            return false;
+        }
+        if (abbreviation() != otherCSA->abbreviation()) {
+            return false;
+        }
+        // TODO other metadata
+    }
+
+    return true;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+CoordinateSystemAxisNNPtr
+CoordinateSystemAxis::alterUnit(const common::UnitOfMeasure &newUnit) const {
+    return create(util::PropertyMap().set(IdentifiedObject::NAME_KEY, name()),
+                  abbreviation(), direction(), newUnit, meridian());
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct CoordinateSystem::Private {
+    std::vector<CoordinateSystemAxisNNPtr> axisList{};
+
+    explicit Private(const std::vector<CoordinateSystemAxisNNPtr> &axisListIn)
+        : axisList(axisListIn) {}
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+CoordinateSystem::CoordinateSystem(
+    const std::vector<CoordinateSystemAxisNNPtr> &axisIn)
+    : d(internal::make_unique<Private>(axisIn)) {}
+
+// ---------------------------------------------------------------------------
+
+#ifdef notdef
+CoordinateSystem::CoordinateSystem(const CoordinateSystem &other)
+    : IdentifiedObject(other), d(internal::make_unique<Private>(*other.d)) {}
+#endif
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+CoordinateSystem::~CoordinateSystem() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the list of axes of this coordinate system.
+ *
+ * @return the axes.
+ */
+const std::vector<CoordinateSystemAxisNNPtr> &
+CoordinateSystem::axisList() PROJ_CONST_DEFN {
+    return d->axisList;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void CoordinateSystem::_exportToWKT(
+    io::WKTFormatter *formatter) const // throw(FormattingException)
+{
+    if (formatter->outputAxis() != io::WKTFormatter::OutputAxisRule::YES) {
+        return;
+    }
+    const bool isWKT2 = formatter->version() == io::WKTFormatter::Version::WKT2;
+
+    const auto &l_axisList = axisList();
+    if (isWKT2) {
+        formatter->startNode(io::WKTConstants::CS, !identifiers().empty());
+        formatter->add(getWKT2Type(formatter->use2018Keywords()));
+        formatter->add(static_cast<int>(l_axisList.size()));
+        formatter->endNode();
+        formatter->startNode(std::string(),
+                             false); // anonymous indentation level
+    }
+
+    common::UnitOfMeasure unit = common::UnitOfMeasure::NONE;
+    bool bAllSameUnit = true;
+    bool bFirstUnit = true;
+    for (const auto &axis : l_axisList) {
+        const auto &l_unit = axis->unit();
+        if (bFirstUnit) {
+            unit = l_unit;
+            bFirstUnit = false;
+        } else if (unit != l_unit) {
+            bAllSameUnit = false;
+        }
+    }
+
+    formatter->pushOutputUnit(
+        isWKT2 && (!bAllSameUnit || !formatter->outputCSUnitOnlyOnceIfSame()));
+
+    int order = 1;
+    const bool disableAbbrev =
+        (l_axisList.size() == 3 &&
+         l_axisList[0]->nameStr() == AxisName::Latitude &&
+         l_axisList[1]->nameStr() == AxisName::Longitude &&
+         l_axisList[2]->nameStr() == AxisName::Ellipsoidal_height);
+
+    for (auto &axis : l_axisList) {
+        int axisOrder = (isWKT2 && l_axisList.size() > 1) ? order : 0;
+        axis->_exportToWKT(formatter, axisOrder, disableAbbrev);
+        order++;
+    }
+    if (isWKT2 && !l_axisList.empty() && bAllSameUnit &&
+        formatter->outputCSUnitOnlyOnceIfSame()) {
+        unit._exportToWKT(formatter);
+    }
+
+    formatter->popOutputUnit();
+
+    if (isWKT2) {
+        formatter->endNode();
+    }
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+bool CoordinateSystem::_isEquivalentTo(
+    const util::IComparable *other,
+    util::IComparable::Criterion criterion) const {
+    auto otherCS = dynamic_cast<const CoordinateSystem *>(other);
+    if (otherCS == nullptr ||
+        !IdentifiedObject::_isEquivalentTo(other, criterion)) {
+        return false;
+    }
+    const auto &list = axisList();
+    const auto &otherList = otherCS->axisList();
+    if (list.size() != otherList.size()) {
+        return false;
+    }
+    if (getWKT2Type(true) != otherCS->getWKT2Type(true)) {
+        return false;
+    }
+    for (size_t i = 0; i < list.size(); i++) {
+        if (!list[i]->_isEquivalentTo(otherList[i].get(), criterion)) {
+            return false;
+        }
+    }
+    return true;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+SphericalCS::~SphericalCS() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+SphericalCS::SphericalCS(const std::vector<CoordinateSystemAxisNNPtr> &axisIn)
+    : CoordinateSystem(axisIn) {}
+
+// ---------------------------------------------------------------------------
+
+#ifdef notdef
+SphericalCS::SphericalCS(const SphericalCS &) = default;
+#endif
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a SphericalCS.
+ *
+ * @param properties See \ref general_properties.
+ * @param axis1 The first axis.
+ * @param axis2 The second axis.
+ * @param axis3 The third axis.
+ * @return a new SphericalCS.
+ */
+SphericalCSNNPtr SphericalCS::create(const util::PropertyMap &properties,
+                                     const CoordinateSystemAxisNNPtr &axis1,
+                                     const CoordinateSystemAxisNNPtr &axis2,
+                                     const CoordinateSystemAxisNNPtr &axis3) {
+    std::vector<CoordinateSystemAxisNNPtr> axis{axis1, axis2, axis3};
+    auto cs(SphericalCS::nn_make_shared<SphericalCS>(axis));
+    cs->setProperties(properties);
+    return cs;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+EllipsoidalCS::~EllipsoidalCS() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+EllipsoidalCS::EllipsoidalCS(
+    const std::vector<CoordinateSystemAxisNNPtr> &axisIn)
+    : CoordinateSystem(axisIn) {}
+
+// ---------------------------------------------------------------------------
+
+#ifdef notdef
+EllipsoidalCS::EllipsoidalCS(const EllipsoidalCS &) = default;
+#endif
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a EllipsoidalCS.
+ *
+ * @param properties See \ref general_properties.
+ * @param axis1 The first axis.
+ * @param axis2 The second axis.
+ * @return a new EllipsoidalCS.
+ */
+EllipsoidalCSNNPtr
+EllipsoidalCS::create(const util::PropertyMap &properties,
+                      const CoordinateSystemAxisNNPtr &axis1,
+                      const CoordinateSystemAxisNNPtr &axis2) {
+    std::vector<CoordinateSystemAxisNNPtr> axis{axis1, axis2};
+    auto cs(EllipsoidalCS::nn_make_shared<EllipsoidalCS>(axis));
+    cs->setProperties(properties);
+    return cs;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a EllipsoidalCS.
+ *
+ * @param properties See \ref general_properties.
+ * @param axis1 The first axis.
+ * @param axis2 The second axis.
+ * @param axis3 The third axis.
+ * @return a new EllipsoidalCS.
+ */
+EllipsoidalCSNNPtr
+EllipsoidalCS::create(const util::PropertyMap &properties,
+                      const CoordinateSystemAxisNNPtr &axis1,
+                      const CoordinateSystemAxisNNPtr &axis2,
+                      const CoordinateSystemAxisNNPtr &axis3) {
+    std::vector<CoordinateSystemAxisNNPtr> axis{axis1, axis2, axis3};
+    auto cs(EllipsoidalCS::nn_make_shared<EllipsoidalCS>(axis));
+    cs->setProperties(properties);
+    return cs;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+CoordinateSystemAxisNNPtr
+CoordinateSystemAxis::createLAT_NORTH(const common::UnitOfMeasure &unit) {
+    return create(
+        util::PropertyMap().set(IdentifiedObject::NAME_KEY, AxisName::Latitude),
+        AxisAbbreviation::lat, AxisDirection::NORTH, unit);
+}
+
+CoordinateSystemAxisNNPtr
+CoordinateSystemAxis::createLONG_EAST(const common::UnitOfMeasure &unit) {
+    return create(util::PropertyMap().set(IdentifiedObject::NAME_KEY,
+                                          AxisName::Longitude),
+                  AxisAbbreviation::lon, AxisDirection::EAST, unit);
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a EllipsoidalCS with a Latitude (first) and Longitude
+ * (second) axis.
+ *
+ * @param unit Angular unit of the axes.
+ * @return a new EllipsoidalCS.
+ */
+EllipsoidalCSNNPtr
+EllipsoidalCS::createLatitudeLongitude(const common::UnitOfMeasure &unit) {
+    return EllipsoidalCS::create(util::PropertyMap(),
+                                 CoordinateSystemAxis::createLAT_NORTH(unit),
+                                 CoordinateSystemAxis::createLONG_EAST(unit));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a EllipsoidalCS with a Latitude (first), Longitude
+ * (second) axis and ellipsoidal height (third) axis.
+ *
+ * @param angularUnit Angular unit of the latitude and longitude axes.
+ * @param linearUnit Linear unit of the ellipsoidal height axis.
+ * @return a new EllipsoidalCS.
+ */
+EllipsoidalCSNNPtr EllipsoidalCS::createLatitudeLongitudeEllipsoidalHeight(
+    const common::UnitOfMeasure &angularUnit,
+    const common::UnitOfMeasure &linearUnit) {
+    return EllipsoidalCS::create(
+        util::PropertyMap(), CoordinateSystemAxis::createLAT_NORTH(angularUnit),
+        CoordinateSystemAxis::createLONG_EAST(angularUnit),
+        CoordinateSystemAxis::create(
+            util::PropertyMap().set(IdentifiedObject::NAME_KEY,
+                                    AxisName::Ellipsoidal_height),
+            AxisAbbreviation::h, AxisDirection::UP, linearUnit));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a EllipsoidalCS with a Longitude (first) and Latitude
+ * (second) axis.
+ *
+ * @param unit Angular unit of the axes.
+ * @return a new EllipsoidalCS.
+ */
+EllipsoidalCSNNPtr
+EllipsoidalCS::createLongitudeLatitude(const common::UnitOfMeasure &unit) {
+    return EllipsoidalCS::create(util::PropertyMap(),
+                                 CoordinateSystemAxis::createLONG_EAST(unit),
+                                 CoordinateSystemAxis::createLAT_NORTH(unit));
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+/** \brief Return the axis order in an enumerated way. */
+EllipsoidalCS::AxisOrder EllipsoidalCS::axisOrder() const {
+    const auto &l_axisList = CoordinateSystem::getPrivate()->axisList;
+    const auto &dir0 = l_axisList[0]->direction();
+    const auto &dir1 = l_axisList[1]->direction();
+    if (&dir0 == &AxisDirection::NORTH && &dir1 == &AxisDirection::EAST) {
+        if (l_axisList.size() == 2) {
+            return AxisOrder::LAT_NORTH_LONG_EAST;
+        } else if (&l_axisList[2]->direction() == &AxisDirection::UP) {
+            return AxisOrder::LAT_NORTH_LONG_EAST_HEIGHT_UP;
+        }
+    } else if (&dir0 == &AxisDirection::EAST &&
+               &dir1 == &AxisDirection::NORTH) {
+        if (l_axisList.size() == 2) {
+            return AxisOrder::LONG_EAST_LAT_NORTH;
+        } else if (&l_axisList[2]->direction() == &AxisDirection::UP) {
+            return AxisOrder::LONG_EAST_LAT_NORTH_HEIGHT_UP;
+        }
+    }
+
+    return AxisOrder::OTHER;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+EllipsoidalCSNNPtr EllipsoidalCS::alterAngularUnit(
+    const common::UnitOfMeasure &angularUnit) const {
+    const auto &l_axisList = CoordinateSystem::getPrivate()->axisList;
+    if (l_axisList.size() == 2) {
+        return EllipsoidalCS::create(util::PropertyMap(),
+                                     l_axisList[0]->alterUnit(angularUnit),
+                                     l_axisList[1]->alterUnit(angularUnit));
+    } else {
+        assert(l_axisList.size() == 3);
+        return EllipsoidalCS::create(
+            util::PropertyMap(), l_axisList[0]->alterUnit(angularUnit),
+            l_axisList[1]->alterUnit(angularUnit), l_axisList[2]);
+    }
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+EllipsoidalCSNNPtr
+EllipsoidalCS::alterLinearUnit(const common::UnitOfMeasure &linearUnit) const {
+    const auto &l_axisList = CoordinateSystem::getPrivate()->axisList;
+    if (l_axisList.size() == 2) {
+        return EllipsoidalCS::create(util::PropertyMap(), l_axisList[0],
+                                     l_axisList[1]);
+    } else {
+        assert(l_axisList.size() == 3);
+        return EllipsoidalCS::create(util::PropertyMap(), l_axisList[0],
+                                     l_axisList[1],
+                                     l_axisList[2]->alterUnit(linearUnit));
+    }
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+VerticalCS::~VerticalCS() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+VerticalCS::VerticalCS(const CoordinateSystemAxisNNPtr &axisIn)
+    : CoordinateSystem(std::vector<CoordinateSystemAxisNNPtr>{axisIn}) {}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+#ifdef notdef
+VerticalCS::VerticalCS(const VerticalCS &) = default;
+#endif
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a VerticalCS.
+ *
+ * @param properties See \ref general_properties.
+ * @param axis The axis.
+ * @return a new VerticalCS.
+ */
+VerticalCSNNPtr VerticalCS::create(const util::PropertyMap &properties,
+                                   const CoordinateSystemAxisNNPtr &axis) {
+    auto cs(VerticalCS::nn_make_shared<VerticalCS>(axis));
+    cs->setProperties(properties);
+    return cs;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a VerticalCS with a Gravity-related height axis
+ *
+ * @param unit linear unit.
+ * @return a new VerticalCS.
+ */
+VerticalCSNNPtr
+VerticalCS::createGravityRelatedHeight(const common::UnitOfMeasure &unit) {
+    auto cs(VerticalCS::nn_make_shared<VerticalCS>(CoordinateSystemAxis::create(
+        util::PropertyMap().set(IdentifiedObject::NAME_KEY,
+                                "Gravity-related height"),
+        "H", AxisDirection::UP, unit)));
+    return cs;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+VerticalCSNNPtr VerticalCS::alterUnit(const common::UnitOfMeasure &unit) const {
+    const auto &l_axisList = CoordinateSystem::getPrivate()->axisList;
+    return VerticalCS::nn_make_shared<VerticalCS>(
+        l_axisList[0]->alterUnit(unit));
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+CartesianCS::~CartesianCS() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+CartesianCS::CartesianCS(const std::vector<CoordinateSystemAxisNNPtr> &axisIn)
+    : CoordinateSystem(axisIn) {}
+
+// ---------------------------------------------------------------------------
+
+#ifdef notdef
+CartesianCS::CartesianCS(const CartesianCS &) = default;
+#endif
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a CartesianCS.
+ *
+ * @param properties See \ref general_properties.
+ * @param axis1 The first axis.
+ * @param axis2 The second axis.
+ * @return a new CartesianCS.
+ */
+CartesianCSNNPtr CartesianCS::create(const util::PropertyMap &properties,
+                                     const CoordinateSystemAxisNNPtr &axis1,
+                                     const CoordinateSystemAxisNNPtr &axis2) {
+    std::vector<CoordinateSystemAxisNNPtr> axis{axis1, axis2};
+    auto cs(CartesianCS::nn_make_shared<CartesianCS>(axis));
+    cs->setProperties(properties);
+    return cs;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a CartesianCS.
+ *
+ * @param properties See \ref general_properties.
+ * @param axis1 The first axis.
+ * @param axis2 The second axis.
+ * @param axis3 The third axis.
+ * @return a new CartesianCS.
+ */
+CartesianCSNNPtr CartesianCS::create(const util::PropertyMap &properties,
+                                     const CoordinateSystemAxisNNPtr &axis1,
+                                     const CoordinateSystemAxisNNPtr &axis2,
+                                     const CoordinateSystemAxisNNPtr &axis3) {
+    std::vector<CoordinateSystemAxisNNPtr> axis{axis1, axis2, axis3};
+    auto cs(CartesianCS::nn_make_shared<CartesianCS>(axis));
+    cs->setProperties(properties);
+    return cs;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a CartesianCS with a Easting (first) and Northing
+ * (second) axis.
+ *
+ * @param unit Linear unit of the axes.
+ * @return a new CartesianCS.
+ */
+CartesianCSNNPtr
+CartesianCS::createEastingNorthing(const common::UnitOfMeasure &unit) {
+    return create(util::PropertyMap(),
+                  CoordinateSystemAxis::create(
+                      util::PropertyMap().set(IdentifiedObject::NAME_KEY,
+                                              AxisName::Easting),
+                      AxisAbbreviation::E, AxisDirection::EAST, unit),
+                  CoordinateSystemAxis::create(
+                      util::PropertyMap().set(IdentifiedObject::NAME_KEY,
+                                              AxisName::Northing),
+                      AxisAbbreviation::N, AxisDirection::NORTH, unit));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a CartesianCS with a Northing (first) and Easting
+ * (second) axis.
+ *
+ * @param unit Linear unit of the axes.
+ * @return a new CartesianCS.
+ */
+CartesianCSNNPtr
+CartesianCS::createNorthingEasting(const common::UnitOfMeasure &unit) {
+    return create(util::PropertyMap(),
+                  CoordinateSystemAxis::create(
+                      util::PropertyMap().set(IdentifiedObject::NAME_KEY,
+                                              AxisName::Northing),
+                      AxisAbbreviation::N, AxisDirection::NORTH, unit),
+                  CoordinateSystemAxis::create(
+                      util::PropertyMap().set(IdentifiedObject::NAME_KEY,
+                                              AxisName::Easting),
+                      AxisAbbreviation::E, AxisDirection::EAST, unit));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a CartesianCS with a Westing (first) and Southing
+ * (second) axis.
+ *
+ * @param unit Linear unit of the axes.
+ * @return a new CartesianCS.
+ */
+CartesianCSNNPtr
+CartesianCS::createWestingSouthing(const common::UnitOfMeasure &unit) {
+    return create(util::PropertyMap(),
+                  CoordinateSystemAxis::create(
+                      util::PropertyMap().set(IdentifiedObject::NAME_KEY,
+                                              AxisName::Easting),
+                      AxisAbbreviation::Y, AxisDirection::WEST, unit),
+                  CoordinateSystemAxis::create(
+                      util::PropertyMap().set(IdentifiedObject::NAME_KEY,
+                                              AxisName::Northing),
+                      AxisAbbreviation::X, AxisDirection::SOUTH, unit));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a CartesianCS, north-pole centered,
+ * with a Easting (first) South-Oriented and
+ * Northing (second) South-Oriented axis.
+ *
+ * @param unit Linear unit of the axes.
+ * @return a new CartesianCS.
+ */
+CartesianCSNNPtr CartesianCS::createNorthPoleEastingSouthNorthingSouth(
+    const common::UnitOfMeasure &unit) {
+    return create(util::PropertyMap(),
+                  CoordinateSystemAxis::create(
+                      util::PropertyMap().set(IdentifiedObject::NAME_KEY,
+                                              AxisName::Easting),
+                      AxisAbbreviation::E, AxisDirection::SOUTH, unit,
+                      Meridian::create(common::Angle(90))),
+                  CoordinateSystemAxis::create(
+                      util::PropertyMap().set(IdentifiedObject::NAME_KEY,
+                                              AxisName::Northing),
+                      AxisAbbreviation::N, AxisDirection::SOUTH, unit,
+                      Meridian::create(common::Angle(180))));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a CartesianCS, south-pole centered,
+ * with a Easting (first) North-Oriented and
+ * Northing (second) North-Oriented axis.
+ *
+ * @param unit Linear unit of the axes.
+ * @return a new CartesianCS.
+ */
+CartesianCSNNPtr CartesianCS::createSouthPoleEastingNorthNorthingNorth(
+    const common::UnitOfMeasure &unit) {
+    return create(util::PropertyMap(),
+                  CoordinateSystemAxis::create(
+                      util::PropertyMap().set(IdentifiedObject::NAME_KEY,
+                                              AxisName::Easting),
+                      AxisAbbreviation::E, AxisDirection::NORTH, unit,
+                      Meridian::create(common::Angle(90))),
+                  CoordinateSystemAxis::create(
+                      util::PropertyMap().set(IdentifiedObject::NAME_KEY,
+                                              AxisName::Northing),
+                      AxisAbbreviation::N, AxisDirection::NORTH, unit,
+                      Meridian::create(common::Angle(0))));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a CartesianCS with the three geocentric axes.
+ *
+ * @param unit Liinear unit of the axes.
+ * @return a new CartesianCS.
+ */
+CartesianCSNNPtr
+CartesianCS::createGeocentric(const common::UnitOfMeasure &unit) {
+    return create(util::PropertyMap(),
+                  CoordinateSystemAxis::create(
+                      util::PropertyMap().set(IdentifiedObject::NAME_KEY,
+                                              AxisName::Geocentric_X),
+                      AxisAbbreviation::X, AxisDirection::GEOCENTRIC_X, unit),
+                  CoordinateSystemAxis::create(
+                      util::PropertyMap().set(IdentifiedObject::NAME_KEY,
+                                              AxisName::Geocentric_Y),
+                      AxisAbbreviation::Y, AxisDirection::GEOCENTRIC_Y, unit),
+                  CoordinateSystemAxis::create(
+                      util::PropertyMap().set(IdentifiedObject::NAME_KEY,
+                                              AxisName::Geocentric_Z),
+                      AxisAbbreviation::Z, AxisDirection::GEOCENTRIC_Z, unit));
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+CartesianCSNNPtr
+CartesianCS::alterUnit(const common::UnitOfMeasure &unit) const {
+    const auto &l_axisList = CoordinateSystem::getPrivate()->axisList;
+    if (l_axisList.size() == 2) {
+        return CartesianCS::create(util::PropertyMap(),
+                                   l_axisList[0]->alterUnit(unit),
+                                   l_axisList[1]->alterUnit(unit));
+    } else {
+        assert(l_axisList.size() == 3);
+        return CartesianCS::create(
+            util::PropertyMap(), l_axisList[0]->alterUnit(unit),
+            l_axisList[1]->alterUnit(unit), l_axisList[2]->alterUnit(unit));
+    }
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+OrdinalCS::~OrdinalCS() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+OrdinalCS::OrdinalCS(const std::vector<CoordinateSystemAxisNNPtr> &axisIn)
+    : CoordinateSystem(axisIn) {}
+
+// ---------------------------------------------------------------------------
+
+#ifdef notdef
+OrdinalCS::OrdinalCS(const OrdinalCS &) = default;
+#endif
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a OrdinalCS.
+ *
+ * @param properties See \ref general_properties.
+ * @param axisIn List of axis.
+ * @return a new OrdinalCS.
+ */
+OrdinalCSNNPtr
+OrdinalCS::create(const util::PropertyMap &properties,
+                  const std::vector<CoordinateSystemAxisNNPtr> &axisIn) {
+    auto cs(OrdinalCS::nn_make_shared<OrdinalCS>(axisIn));
+    cs->setProperties(properties);
+    return cs;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+ParametricCS::~ParametricCS() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+ParametricCS::ParametricCS(const std::vector<CoordinateSystemAxisNNPtr> &axisIn)
+    : CoordinateSystem(axisIn) {}
+
+// ---------------------------------------------------------------------------
+
+#ifdef notdef
+ParametricCS::ParametricCS(const ParametricCS &) = default;
+#endif
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ParametricCS.
+ *
+ * @param properties See \ref general_properties.
+ * @param axisIn Axis.
+ * @return a new ParametricCS.
+ */
+ParametricCSNNPtr
+ParametricCS::create(const util::PropertyMap &properties,
+                     const CoordinateSystemAxisNNPtr &axisIn) {
+    auto cs(ParametricCS::nn_make_shared<ParametricCS>(
+        std::vector<CoordinateSystemAxisNNPtr>{axisIn}));
+    cs->setProperties(properties);
+    return cs;
+}
+
+// ---------------------------------------------------------------------------
+
+AxisDirection::AxisDirection(const std::string &nameIn) : CodeList(nameIn) {
+    assert(registry.find(nameIn) == registry.end());
+    registry[nameIn] = this;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+const AxisDirection *
+AxisDirection::valueOf(const std::string &nameIn) noexcept {
+    auto iter = registry.find(nameIn);
+    if (iter == registry.end())
+        return nullptr;
+    return iter->second;
+}
+//! @endcond
+
+//! @cond Doxygen_Suppress
+// ---------------------------------------------------------------------------
+
+AxisDirectionWKT1::AxisDirectionWKT1(const std::string &nameIn)
+    : CodeList(nameIn) {
+    assert(registry.find(nameIn) == registry.end());
+    registry[nameIn] = this;
+}
+
+// ---------------------------------------------------------------------------
+
+const AxisDirectionWKT1 *AxisDirectionWKT1::valueOf(const std::string &nameIn) {
+    auto iter = registry.find(nameIn);
+    if (iter == registry.end())
+        return nullptr;
+    return iter->second;
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+TemporalCS::~TemporalCS() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+TemporalCS::TemporalCS(const CoordinateSystemAxisNNPtr &axisIn)
+    : CoordinateSystem(std::vector<CoordinateSystemAxisNNPtr>{axisIn}) {}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+DateTimeTemporalCS::~DateTimeTemporalCS() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+DateTimeTemporalCS::DateTimeTemporalCS(const CoordinateSystemAxisNNPtr &axisIn)
+    : TemporalCS(axisIn) {}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a DateTimeTemporalCS.
+ *
+ * @param properties See \ref general_properties.
+ * @param axisIn The axis.
+ * @return a new DateTimeTemporalCS.
+ */
+DateTimeTemporalCSNNPtr
+DateTimeTemporalCS::create(const util::PropertyMap &properties,
+                           const CoordinateSystemAxisNNPtr &axisIn) {
+    auto cs(DateTimeTemporalCS::nn_make_shared<DateTimeTemporalCS>(axisIn));
+    cs->setProperties(properties);
+    return cs;
+}
+
+// ---------------------------------------------------------------------------
+
+std::string DateTimeTemporalCS::getWKT2Type(bool use2018Keywords) const {
+    return use2018Keywords ? "TemporalDateTime" : "temporal";
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+TemporalCountCS::~TemporalCountCS() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+TemporalCountCS::TemporalCountCS(const CoordinateSystemAxisNNPtr &axisIn)
+    : TemporalCS(axisIn) {}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a TemporalCountCS.
+ *
+ * @param properties See \ref general_properties.
+ * @param axisIn The axis.
+ * @return a new TemporalCountCS.
+ */
+TemporalCountCSNNPtr
+TemporalCountCS::create(const util::PropertyMap &properties,
+                        const CoordinateSystemAxisNNPtr &axisIn) {
+    auto cs(TemporalCountCS::nn_make_shared<TemporalCountCS>(axisIn));
+    cs->setProperties(properties);
+    return cs;
+}
+
+// ---------------------------------------------------------------------------
+
+std::string TemporalCountCS::getWKT2Type(bool use2018Keywords) const {
+    return use2018Keywords ? "TemporalCount" : "temporal";
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+TemporalMeasureCS::~TemporalMeasureCS() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+TemporalMeasureCS::TemporalMeasureCS(const CoordinateSystemAxisNNPtr &axisIn)
+    : TemporalCS(axisIn) {}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a TemporalMeasureCS.
+ *
+ * @param properties See \ref general_properties.
+ * @param axisIn The axis.
+ * @return a new TemporalMeasureCS.
+ */
+TemporalMeasureCSNNPtr
+TemporalMeasureCS::create(const util::PropertyMap &properties,
+                          const CoordinateSystemAxisNNPtr &axisIn) {
+    auto cs(TemporalMeasureCS::nn_make_shared<TemporalMeasureCS>(axisIn));
+    cs->setProperties(properties);
+    return cs;
+}
+
+// ---------------------------------------------------------------------------
+
+std::string TemporalMeasureCS::getWKT2Type(bool use2018Keywords) const {
+    return use2018Keywords ? "TemporalMeasure" : "temporal";
+}
+
+} // namespace cs
+NS_PROJ_END
diff --git a/src/iso19111/crs.cpp b/src/iso19111/crs.cpp
new file mode 100644
index 00000000..a05470ff
--- /dev/null
+++ b/src/iso19111/crs.cpp
@@ -0,0 +1,4971 @@
+/******************************************************************************
+ *
+ * Project:  PROJ
+ * Purpose:  ISO19111:2018 implementation
+ * Author:   Even Rouault <even dot rouault at spatialys dot com>
+ *
+ ******************************************************************************
+ * Copyright (c) 2018, Even Rouault <even dot rouault at spatialys dot com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ ****************************************************************************/
+
+#ifndef FROM_PROJ_CPP
+#define FROM_PROJ_CPP
+#endif
+
+//! @cond Doxygen_Suppress
+#define DO_NOT_DEFINE_EXTERN_DERIVED_CRS_TEMPLATE
+//! @endcond
+
+#include "proj/crs.hpp"
+#include "proj/common.hpp"
+#include "proj/coordinateoperation.hpp"
+#include "proj/coordinatesystem.hpp"
+#include "proj/io.hpp"
+#include "proj/util.hpp"
+
+#include "proj/internal/coordinatesystem_internal.hpp"
+#include "proj/internal/internal.hpp"
+#include "proj/internal/io_internal.hpp"
+
+#include <algorithm>
+#include <cassert>
+#include <cstring>
+#include <iostream>
+#include <memory>
+#include <string>
+#include <vector>
+
+using namespace NS_PROJ::internal;
+
+#if 0
+namespace dropbox{ namespace oxygen {
+template<> nn<NS_PROJ::crs::CRSPtr>::~nn() = default;
+template<> nn<NS_PROJ::crs::SingleCRSPtr>::~nn() = default;
+template<> nn<NS_PROJ::crs::GeodeticCRSPtr>::~nn() = default;
+template<> nn<NS_PROJ::crs::GeographicCRSPtr>::~nn() = default;
+template<> nn<NS_PROJ::crs::DerivedCRSPtr>::~nn() = default;
+template<> nn<NS_PROJ::crs::ProjectedCRSPtr>::~nn() = default;
+template<> nn<NS_PROJ::crs::VerticalCRSPtr>::~nn() = default;
+template<> nn<NS_PROJ::crs::CompoundCRSPtr>::~nn() = default;
+template<> nn<NS_PROJ::crs::TemporalCRSPtr>::~nn() = default;
+template<> nn<NS_PROJ::crs::EngineeringCRSPtr>::~nn() = default;
+template<> nn<NS_PROJ::crs::ParametricCRSPtr>::~nn() = default;
+template<> nn<NS_PROJ::crs::BoundCRSPtr>::~nn() = default;
+template<> nn<NS_PROJ::crs::DerivedGeodeticCRSPtr>::~nn() = default;
+template<> nn<NS_PROJ::crs::DerivedGeographicCRSPtr>::~nn() = default;
+template<> nn<NS_PROJ::crs::DerivedProjectedCRSPtr>::~nn() = default;
+template<> nn<NS_PROJ::crs::DerivedVerticalCRSPtr>::~nn() = default;
+template<> nn<NS_PROJ::crs::DerivedTemporalCRSPtr>::~nn() = default;
+template<> nn<NS_PROJ::crs::DerivedEngineeringCRSPtr>::~nn() = default;
+template<> nn<NS_PROJ::crs::DerivedParametricCRSPtr>::~nn() = default;
+}}
+#endif
+
+NS_PROJ_START
+
+namespace crs {
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct CRS::Private {
+    BoundCRSPtr canonicalBoundCRS_{};
+    std::string extensionProj4_{};
+    bool implicitCS_ = false;
+
+    void setImplicitCS(const util::PropertyMap &properties) {
+        const auto pVal = properties.get("IMPLICIT_CS");
+        if (pVal) {
+            if (const auto genVal =
+                    dynamic_cast<const util::BoxedValue *>(pVal->get())) {
+                if (genVal->type() == util::BoxedValue::Type::BOOLEAN &&
+                    genVal->booleanValue()) {
+                    implicitCS_ = true;
+                }
+            }
+        }
+    }
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+CRS::CRS() : d(internal::make_unique<Private>()) {}
+
+// ---------------------------------------------------------------------------
+
+CRS::CRS(const CRS &other)
+    : ObjectUsage(other), d(internal::make_unique<Private>(*(other.d))) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+CRS::~CRS() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the BoundCRS potentially attached to this CRS.
+ *
+ * In the case this method is called on a object returned by
+ * BoundCRS::baseCRSWithCanonicalBoundCRS(), this method will return this
+ * BoundCRS
+ *
+ * @return a BoundCRSPtr, that might be null.
+ */
+const BoundCRSPtr &CRS::canonicalBoundCRS() PROJ_CONST_DEFN {
+    return d->canonicalBoundCRS_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the GeodeticCRS of the CRS.
+ *
+ * Returns the GeodeticCRS contained in a CRS. This works currently with
+ * input parameters of type GeodeticCRS or derived, ProjectedCRS,
+ * CompoundCRS or BoundCRS.
+ *
+ * @return a GeodeticCRSPtr, that might be null.
+ */
+GeodeticCRSPtr CRS::extractGeodeticCRS() const {
+    auto raw = extractGeodeticCRSRaw();
+    if (raw) {
+        return std::dynamic_pointer_cast<GeodeticCRS>(
+            raw->shared_from_this().as_nullable());
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+const GeodeticCRS *CRS::extractGeodeticCRSRaw() const {
+    auto geodCRS = dynamic_cast<const GeodeticCRS *>(this);
+    if (geodCRS) {
+        return geodCRS;
+    }
+    auto projCRS = dynamic_cast<const ProjectedCRS *>(this);
+    if (projCRS) {
+        return projCRS->baseCRS()->extractGeodeticCRSRaw();
+    }
+    auto compoundCRS = dynamic_cast<const CompoundCRS *>(this);
+    if (compoundCRS) {
+        for (const auto &subCrs : compoundCRS->componentReferenceSystems()) {
+            auto retGeogCRS = subCrs->extractGeodeticCRSRaw();
+            if (retGeogCRS) {
+                return retGeogCRS;
+            }
+        }
+    }
+    auto boundCRS = dynamic_cast<const BoundCRS *>(this);
+    if (boundCRS) {
+        return boundCRS->baseCRS()->extractGeodeticCRSRaw();
+    }
+    return nullptr;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+const std::string &CRS::getExtensionProj4() const noexcept {
+    return d->extensionProj4_;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the GeographicCRS of the CRS.
+ *
+ * Returns the GeographicCRS contained in a CRS. This works currently with
+ * input parameters of type GeographicCRS or derived, ProjectedCRS,
+ * CompoundCRS or BoundCRS.
+ *
+ * @return a GeographicCRSPtr, that might be null.
+ */
+GeographicCRSPtr CRS::extractGeographicCRS() const {
+    auto raw = extractGeodeticCRSRaw();
+    if (raw) {
+        return std::dynamic_pointer_cast<GeographicCRS>(
+            raw->shared_from_this().as_nullable());
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static util::PropertyMap
+createPropertyMap(const common::IdentifiedObject *obj) {
+    auto props = util::PropertyMap().set(common::IdentifiedObject::NAME_KEY,
+                                         obj->nameStr());
+    if (obj->isDeprecated()) {
+        props.set(common::IdentifiedObject::DEPRECATED_KEY, true);
+    }
+    return props;
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+CRSNNPtr CRS::alterGeodeticCRS(const GeodeticCRSNNPtr &newGeodCRS) const {
+    auto geodCRS = dynamic_cast<const GeodeticCRS *>(this);
+    if (geodCRS) {
+        return newGeodCRS;
+    }
+
+    auto projCRS = dynamic_cast<const ProjectedCRS *>(this);
+    if (projCRS) {
+        return ProjectedCRS::create(createPropertyMap(this), newGeodCRS,
+                                    projCRS->derivingConversionRef(),
+                                    projCRS->coordinateSystem());
+    }
+
+    auto compoundCRS = dynamic_cast<const CompoundCRS *>(this);
+    if (compoundCRS) {
+        std::vector<CRSNNPtr> components;
+        for (const auto &subCrs : compoundCRS->componentReferenceSystems()) {
+            components.emplace_back(subCrs->alterGeodeticCRS(newGeodCRS));
+        }
+        return CompoundCRS::create(createPropertyMap(this), components);
+    }
+
+    return NN_NO_CHECK(
+        std::dynamic_pointer_cast<CRS>(shared_from_this().as_nullable()));
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+CRSNNPtr CRS::alterCSLinearUnit(const common::UnitOfMeasure &unit) const {
+    {
+        auto projCRS = dynamic_cast<const ProjectedCRS *>(this);
+        if (projCRS) {
+            return ProjectedCRS::create(
+                createPropertyMap(this), projCRS->baseCRS(),
+                projCRS->derivingConversionRef(),
+                projCRS->coordinateSystem()->alterUnit(unit));
+        }
+    }
+
+    {
+        auto geodCRS = dynamic_cast<const GeodeticCRS *>(this);
+        if (geodCRS && geodCRS->isGeocentric()) {
+            auto cs = dynamic_cast<const cs::CartesianCS *>(
+                geodCRS->coordinateSystem().get());
+            assert(cs);
+            return GeodeticCRS::create(
+                createPropertyMap(this), geodCRS->datum(),
+                geodCRS->datumEnsemble(), cs->alterUnit(unit));
+        }
+    }
+
+    {
+        auto geogCRS = dynamic_cast<const GeographicCRS *>(this);
+        if (geogCRS && geogCRS->coordinateSystem()->axisList().size() == 3) {
+            return GeographicCRS::create(
+                createPropertyMap(this), geogCRS->datum(),
+                geogCRS->datumEnsemble(),
+                geogCRS->coordinateSystem()->alterLinearUnit(unit));
+        }
+    }
+
+    {
+        auto vertCRS = dynamic_cast<const VerticalCRS *>(this);
+        if (vertCRS) {
+            return VerticalCRS::create(
+                createPropertyMap(this), vertCRS->datum(),
+                vertCRS->datumEnsemble(),
+                vertCRS->coordinateSystem()->alterUnit(unit));
+        }
+    }
+
+    {
+        auto engCRS = dynamic_cast<const EngineeringCRS *>(this);
+        if (engCRS) {
+            auto cartCS = util::nn_dynamic_pointer_cast<cs::CartesianCS>(
+                engCRS->coordinateSystem());
+            if (cartCS) {
+                auto props = createPropertyMap(this);
+                props.set("FORCE_OUTPUT_CS", true);
+                return EngineeringCRS::create(props, engCRS->datum(),
+                                              cartCS->alterUnit(unit));
+            } else {
+                auto vertCS = util::nn_dynamic_pointer_cast<cs::VerticalCS>(
+                    engCRS->coordinateSystem());
+                if (vertCS) {
+                    auto props = createPropertyMap(this);
+                    props.set("FORCE_OUTPUT_CS", true);
+                    return EngineeringCRS::create(props, engCRS->datum(),
+                                                  vertCS->alterUnit(unit));
+                }
+            }
+        }
+    }
+
+    return NN_NO_CHECK(
+        std::dynamic_pointer_cast<CRS>(shared_from_this().as_nullable()));
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the VerticalCRS of the CRS.
+ *
+ * Returns the VerticalCRS contained in a CRS. This works currently with
+ * input parameters of type VerticalCRS or derived, CompoundCRS or BoundCRS.
+ *
+ * @return a VerticalCRSPtr, that might be null.
+ */
+VerticalCRSPtr CRS::extractVerticalCRS() const {
+    auto vertCRS = dynamic_cast<const VerticalCRS *>(this);
+    if (vertCRS) {
+        return std::dynamic_pointer_cast<VerticalCRS>(
+            shared_from_this().as_nullable());
+    }
+    auto compoundCRS = dynamic_cast<const CompoundCRS *>(this);
+    if (compoundCRS) {
+        for (const auto &subCrs : compoundCRS->componentReferenceSystems()) {
+            auto retVertCRS = subCrs->extractVerticalCRS();
+            if (retVertCRS) {
+                return retVertCRS;
+            }
+        }
+    }
+    auto boundCRS = dynamic_cast<const BoundCRS *>(this);
+    if (boundCRS) {
+        return boundCRS->baseCRS()->extractVerticalCRS();
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns potentially
+ * a BoundCRS, with a transformation to EPSG:4326, wrapping this CRS
+ *
+ * If no such BoundCRS is possible, the object will be returned.
+ *
+ * The purpose of this method is to be able to format a PROJ.4 string with
+ * a +towgs84 parameter or a WKT1:GDAL string with a TOWGS node.
+ *
+ * This method will fetch the GeographicCRS of this CRS and find a
+ * transformation to EPSG:4326 using the domain of the validity of the main CRS.
+ *
+ * @return a CRS.
+ */
+CRSNNPtr
+CRS::createBoundCRSToWGS84IfPossible(const io::DatabaseContextPtr &dbContext,
+                                     bool allowIntermediateCRS) const {
+    auto thisAsCRS = NN_NO_CHECK(
+        std::static_pointer_cast<CRS>(shared_from_this().as_nullable()));
+    auto boundCRS = util::nn_dynamic_pointer_cast<BoundCRS>(thisAsCRS);
+    if (!boundCRS) {
+        boundCRS = canonicalBoundCRS();
+    }
+    if (boundCRS) {
+        if (boundCRS->hubCRS()->_isEquivalentTo(
+                GeographicCRS::EPSG_4326.get(),
+                util::IComparable::Criterion::EQUIVALENT)) {
+            return NN_NO_CHECK(boundCRS);
+        }
+    }
+
+    auto geodCRS = util::nn_dynamic_pointer_cast<GeodeticCRS>(thisAsCRS);
+    auto geogCRS = extractGeographicCRS();
+    auto hubCRS = util::nn_static_pointer_cast<CRS>(GeographicCRS::EPSG_4326);
+    if (geodCRS && !geogCRS) {
+        if (geodCRS->_isEquivalentTo(
+                GeographicCRS::EPSG_4978.get(),
+                util::IComparable::Criterion::EQUIVALENT)) {
+            return thisAsCRS;
+        }
+        hubCRS = util::nn_static_pointer_cast<CRS>(GeodeticCRS::EPSG_4978);
+    } else if (!geogCRS ||
+               geogCRS->_isEquivalentTo(
+                   GeographicCRS::EPSG_4326.get(),
+                   util::IComparable::Criterion::EQUIVALENT)) {
+        return thisAsCRS;
+    } else {
+        geodCRS = geogCRS;
+    }
+
+    if (!dbContext) {
+        return thisAsCRS;
+    }
+
+    const auto &l_domains = domains();
+    metadata::ExtentPtr extent;
+    if (!l_domains.empty()) {
+        extent = l_domains[0]->domainOfValidity();
+    }
+
+    std::string crs_authority;
+    const auto &l_identifiers = identifiers();
+    // If the object has an authority, restrict the transformations to
+    // come from that codespace too. This avoids for example EPSG:4269
+    // (NAD83) to use a (dubious) ESRI transformation.
+    if (!l_identifiers.empty()) {
+        crs_authority = *(l_identifiers[0]->codeSpace());
+    }
+
+    auto authorities = dbContext->getAllowedAuthorities(crs_authority, "EPSG");
+    if (authorities.empty()) {
+        authorities.emplace_back();
+    }
+    for (const auto &authority : authorities) {
+        try {
+
+            auto authFactory = io::AuthorityFactory::create(
+                NN_NO_CHECK(dbContext),
+                authority == "any" ? std::string() : authority);
+            auto ctxt = operation::CoordinateOperationContext::create(
+                authFactory, extent, 0.0);
+            ctxt->setAllowUseIntermediateCRS(allowIntermediateCRS);
+            // ctxt->setSpatialCriterion(
+            //    operation::CoordinateOperationContext::SpatialCriterion::PARTIAL_INTERSECTION);
+            auto list =
+                operation::CoordinateOperationFactory::create()
+                    ->createOperations(NN_NO_CHECK(geodCRS), hubCRS, ctxt);
+            for (const auto &op : list) {
+                auto transf =
+                    util::nn_dynamic_pointer_cast<operation::Transformation>(
+                        op);
+                if (transf && !starts_with(transf->nameStr(), "Null geo")) {
+                    try {
+                        transf->getTOWGS84Parameters();
+                    } catch (const std::exception &) {
+                        continue;
+                    }
+                    return util::nn_static_pointer_cast<CRS>(BoundCRS::create(
+                        thisAsCRS, hubCRS, NN_NO_CHECK(transf)));
+                } else {
+                    auto concatenated =
+                        dynamic_cast<const operation::ConcatenatedOperation *>(
+                            op.get());
+                    if (concatenated) {
+                        // Case for EPSG:4807 / "NTF (Paris)" that is made of a
+                        // longitude rotation followed by a Helmert
+                        // The prime meridian shift will be accounted elsewhere
+                        const auto &subops = concatenated->operations();
+                        if (subops.size() == 2) {
+                            auto firstOpIsTransformation =
+                                dynamic_cast<const operation::Transformation *>(
+                                    subops[0].get());
+                            auto firstOpIsConversion =
+                                dynamic_cast<const operation::Conversion *>(
+                                    subops[0].get());
+                            if ((firstOpIsTransformation &&
+                                 firstOpIsTransformation
+                                     ->isLongitudeRotation()) ||
+                                (dynamic_cast<DerivedCRS *>(thisAsCRS.get()) &&
+                                 firstOpIsConversion)) {
+                                transf = util::nn_dynamic_pointer_cast<
+                                    operation::Transformation>(subops[1]);
+                                if (transf &&
+                                    !starts_with(transf->nameStr(),
+                                                 "Null geo")) {
+                                    try {
+                                        transf->getTOWGS84Parameters();
+                                    } catch (const std::exception &) {
+                                        continue;
+                                    }
+                                    return util::nn_static_pointer_cast<CRS>(
+                                        BoundCRS::create(thisAsCRS, hubCRS,
+                                                         NN_NO_CHECK(transf)));
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+        } catch (const std::exception &) {
+        }
+    }
+    return thisAsCRS;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns a CRS whose coordinate system does not contain a vertical
+ * component
+ *
+ * @return a CRS.
+ */
+CRSNNPtr CRS::stripVerticalComponent() const {
+    auto self = NN_NO_CHECK(
+        std::dynamic_pointer_cast<CRS>(shared_from_this().as_nullable()));
+
+    auto geogCRS = dynamic_cast<const GeographicCRS *>(this);
+    if (geogCRS) {
+        const auto &axisList = geogCRS->coordinateSystem()->axisList();
+        if (axisList.size() == 3) {
+            auto cs = cs::EllipsoidalCS::create(util::PropertyMap(),
+                                                axisList[0], axisList[1]);
+            return util::nn_static_pointer_cast<CRS>(GeographicCRS::create(
+                util::PropertyMap().set(common::IdentifiedObject::NAME_KEY,
+                                        nameStr()),
+                geogCRS->datum(), geogCRS->datumEnsemble(), cs));
+        }
+    }
+    auto projCRS = dynamic_cast<const ProjectedCRS *>(this);
+    if (projCRS) {
+        const auto &axisList = projCRS->coordinateSystem()->axisList();
+        if (axisList.size() == 3) {
+            auto cs = cs::CartesianCS::create(util::PropertyMap(), axisList[0],
+                                              axisList[1]);
+            return util::nn_static_pointer_cast<CRS>(ProjectedCRS::create(
+                util::PropertyMap().set(common::IdentifiedObject::NAME_KEY,
+                                        nameStr()),
+                projCRS->baseCRS(), projCRS->derivingConversion(), cs));
+        }
+    }
+    return self;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+/** \brief Return a shallow clone of this object. */
+CRSNNPtr CRS::shallowClone() const { return _shallowClone(); }
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+CRSNNPtr CRS::alterName(const std::string &newName) const {
+    auto crs = shallowClone();
+    auto newNameMod(newName);
+    auto props = util::PropertyMap();
+    if (ends_with(newNameMod, " (deprecated)")) {
+        newNameMod.resize(newNameMod.size() - strlen(" (deprecated)"));
+        props.set(common::IdentifiedObject::DEPRECATED_KEY, true);
+    }
+    props.set(common::IdentifiedObject::NAME_KEY, newNameMod);
+    crs->setProperties(props);
+    return crs;
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+CRSNNPtr CRS::alterId(const std::string &authName,
+                      const std::string &code) const {
+    auto crs = shallowClone();
+    auto props = util::PropertyMap();
+    props.set(metadata::Identifier::CODESPACE_KEY, authName)
+        .set(metadata::Identifier::CODE_KEY, code);
+    crs->setProperties(props);
+    return crs;
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Identify the CRS with reference CRSs.
+ *
+ * The candidate CRSs are either hard-coded, or looked in the database when
+ * authorityFactory is not null.
+ *
+ * The method returns a list of matching reference CRS, and the percentage
+ * (0-100) of confidence in the match. The list is sorted by decreasing
+ * confidence.
+ *
+ * 100% means that the name of the reference entry
+ * perfectly matches the CRS name, and both are equivalent. In which case a
+ * single result is returned.
+ * 90% means that CRS are equivalent, but the names are not exactly the same.
+ * 70% means that CRS are equivalent), but the names do not match at all.
+ * 25% means that the CRS are not equivalent, but there is some similarity in
+ * the names.
+ * Other confidence values may be returned by some specialized implementations.
+ *
+ * This is implemented for GeodeticCRS, ProjectedCRS, VerticalCRS and
+ * CompoundCRS.
+ *
+ * @param authorityFactory Authority factory (or null, but degraded
+ * functionality)
+ * @return a list of matching reference CRS, and the percentage (0-100) of
+ * confidence in the match.
+ */
+std::list<std::pair<CRSNNPtr, int>>
+CRS::identify(const io::AuthorityFactoryPtr &authorityFactory) const {
+    return _identify(authorityFactory);
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return CRSs that are non-deprecated substitutes for the current CRS.
+ */
+std::list<CRSNNPtr>
+CRS::getNonDeprecated(const io::DatabaseContextNNPtr &dbContext) const {
+    std::list<CRSNNPtr> res;
+    const auto &l_identifiers = identifiers();
+    if (l_identifiers.empty()) {
+        return res;
+    }
+    const char *tableName = nullptr;
+    if (dynamic_cast<const GeodeticCRS *>(this)) {
+        tableName = "geodetic_crs";
+    } else if (dynamic_cast<const ProjectedCRS *>(this)) {
+        tableName = "projected_crs";
+    } else if (dynamic_cast<const VerticalCRS *>(this)) {
+        tableName = "vertical_crs";
+    } else if (dynamic_cast<const CompoundCRS *>(this)) {
+        tableName = "compound_crs";
+    }
+    if (!tableName) {
+        return res;
+    }
+    const auto &id = l_identifiers[0];
+    auto tmpRes =
+        dbContext->getNonDeprecated(tableName, *(id->codeSpace()), id->code());
+    for (const auto &pair : tmpRes) {
+        res.emplace_back(io::AuthorityFactory::create(dbContext, pair.first)
+                             ->createCoordinateReferenceSystem(pair.second));
+    }
+    return res;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+std::list<std::pair<CRSNNPtr, int>>
+CRS::_identify(const io::AuthorityFactoryPtr &) const {
+    return {};
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct SingleCRS::Private {
+    datum::DatumPtr datum{};
+    datum::DatumEnsemblePtr datumEnsemble{};
+    cs::CoordinateSystemNNPtr coordinateSystem;
+
+    Private(const datum::DatumPtr &datumIn,
+            const datum::DatumEnsemblePtr &datumEnsembleIn,
+            const cs::CoordinateSystemNNPtr &csIn)
+        : datum(datumIn), datumEnsemble(datumEnsembleIn),
+          coordinateSystem(csIn) {
+        if ((datum ? 1 : 0) + (datumEnsemble ? 1 : 0) != 1) {
+            throw util::Exception("datum or datumEnsemble should be set");
+        }
+    }
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+SingleCRS::SingleCRS(const datum::DatumPtr &datumIn,
+                     const datum::DatumEnsemblePtr &datumEnsembleIn,
+                     const cs::CoordinateSystemNNPtr &csIn)
+    : d(internal::make_unique<Private>(datumIn, datumEnsembleIn, csIn)) {}
+
+// ---------------------------------------------------------------------------
+
+SingleCRS::SingleCRS(const SingleCRS &other)
+    : CRS(other), d(internal::make_unique<Private>(*other.d)) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+SingleCRS::~SingleCRS() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the datum::Datum associated with the CRS.
+ *
+ * This might be null, in which case datumEnsemble() return will not be null.
+ *
+ * @return a Datum that might be null.
+ */
+const datum::DatumPtr &SingleCRS::datum() PROJ_CONST_DEFN { return d->datum; }
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the datum::DatumEnsemble associated with the CRS.
+ *
+ * This might be null, in which case datum() return will not be null.
+ *
+ * @return a DatumEnsemble that might be null.
+ */
+const datum::DatumEnsemblePtr &SingleCRS::datumEnsemble() PROJ_CONST_DEFN {
+    return d->datumEnsemble;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the cs::CoordinateSystem associated with the CRS.
+ *
+ * This might be null, in which case datumEnsemble() return will not be null.
+ *
+ * @return a CoordinateSystem that might be null.
+ */
+const cs::CoordinateSystemNNPtr &SingleCRS::coordinateSystem() PROJ_CONST_DEFN {
+    return d->coordinateSystem;
+}
+
+// ---------------------------------------------------------------------------
+
+bool SingleCRS::baseIsEquivalentTo(
+    const util::IComparable *other,
+    util::IComparable::Criterion criterion) const {
+    auto otherSingleCRS = dynamic_cast<const SingleCRS *>(other);
+    if (otherSingleCRS == nullptr ||
+        (criterion == util::IComparable::Criterion::STRICT &&
+         !ObjectUsage::_isEquivalentTo(other, criterion))) {
+        return false;
+    }
+    const auto &thisDatum = d->datum;
+    const auto &otherDatum = otherSingleCRS->d->datum;
+    if (thisDatum) {
+        if (!thisDatum->_isEquivalentTo(otherDatum.get(), criterion)) {
+            return false;
+        }
+    } else {
+        if (otherDatum) {
+            return false;
+        }
+    }
+
+    // TODO test DatumEnsemble
+    return d->coordinateSystem->_isEquivalentTo(
+        otherSingleCRS->d->coordinateSystem.get(), criterion);
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void SingleCRS::exportDatumOrDatumEnsembleToWkt(
+    io::WKTFormatter *formatter) const // throw(io::FormattingException)
+{
+    const auto &l_datum = d->datum;
+    if (l_datum) {
+        l_datum->_exportToWKT(formatter);
+    } else {
+        const auto &l_datumEnsemble = d->datumEnsemble;
+        assert(l_datumEnsemble);
+        l_datumEnsemble->_exportToWKT(formatter);
+    }
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct GeodeticCRS::Private {
+    std::vector<operation::PointMotionOperationNNPtr> velocityModel{};
+    datum::GeodeticReferenceFramePtr datum_;
+
+    explicit Private(const datum::GeodeticReferenceFramePtr &datumIn)
+        : datum_(datumIn) {}
+};
+
+// ---------------------------------------------------------------------------
+
+static const datum::DatumEnsemblePtr &
+checkEnsembleForGeodeticCRS(const datum::GeodeticReferenceFramePtr &datumIn,
+                            const datum::DatumEnsemblePtr &ensemble) {
+    const char *msg = "One of Datum or DatumEnsemble should be defined";
+    if (datumIn) {
+        if (!ensemble) {
+            return ensemble;
+        }
+        msg = "Datum and DatumEnsemble should not be defined";
+    } else if (ensemble) {
+        const auto &datums = ensemble->datums();
+        assert(!datums.empty());
+        auto grfFirst =
+            dynamic_cast<datum::GeodeticReferenceFrame *>(datums[0].get());
+        if (grfFirst) {
+            return ensemble;
+        }
+        msg = "Ensemble should contain GeodeticReferenceFrame";
+    }
+    throw util::Exception(msg);
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+GeodeticCRS::GeodeticCRS(const datum::GeodeticReferenceFramePtr &datumIn,
+                         const datum::DatumEnsemblePtr &datumEnsembleIn,
+                         const cs::EllipsoidalCSNNPtr &csIn)
+    : SingleCRS(datumIn, checkEnsembleForGeodeticCRS(datumIn, datumEnsembleIn),
+                csIn),
+      d(internal::make_unique<Private>(datumIn)) {}
+
+// ---------------------------------------------------------------------------
+
+GeodeticCRS::GeodeticCRS(const datum::GeodeticReferenceFramePtr &datumIn,
+                         const datum::DatumEnsemblePtr &datumEnsembleIn,
+                         const cs::SphericalCSNNPtr &csIn)
+    : SingleCRS(datumIn, checkEnsembleForGeodeticCRS(datumIn, datumEnsembleIn),
+                csIn),
+      d(internal::make_unique<Private>(datumIn)) {}
+
+// ---------------------------------------------------------------------------
+
+GeodeticCRS::GeodeticCRS(const datum::GeodeticReferenceFramePtr &datumIn,
+                         const datum::DatumEnsemblePtr &datumEnsembleIn,
+                         const cs::CartesianCSNNPtr &csIn)
+    : SingleCRS(datumIn, checkEnsembleForGeodeticCRS(datumIn, datumEnsembleIn),
+                csIn),
+      d(internal::make_unique<Private>(datumIn)) {}
+
+// ---------------------------------------------------------------------------
+
+GeodeticCRS::GeodeticCRS(const GeodeticCRS &other)
+    : SingleCRS(other), d(internal::make_unique<Private>(*other.d)) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+GeodeticCRS::~GeodeticCRS() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+CRSNNPtr GeodeticCRS::_shallowClone() const {
+    auto crs(GeodeticCRS::nn_make_shared<GeodeticCRS>(*this));
+    crs->assignSelf(crs);
+    return crs;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the datum::GeodeticReferenceFrame associated with the CRS.
+ *
+ * @return a GeodeticReferenceFrame or null (in which case datumEnsemble()
+ * should return a non-null pointer.)
+ */
+const datum::GeodeticReferenceFramePtr &GeodeticCRS::datum() PROJ_CONST_DEFN {
+    return d->datum_;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static datum::GeodeticReferenceFrame *oneDatum(const GeodeticCRS *crs) {
+    const auto &l_datumEnsemble = crs->datumEnsemble();
+    assert(l_datumEnsemble);
+    const auto &l_datums = l_datumEnsemble->datums();
+    return static_cast<datum::GeodeticReferenceFrame *>(l_datums[0].get());
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the PrimeMeridian associated with the GeodeticReferenceFrame
+ * or with one of the GeodeticReferenceFrame of the datumEnsemble().
+ *
+ * @return the PrimeMeridian.
+ */
+const datum::PrimeMeridianNNPtr &GeodeticCRS::primeMeridian() PROJ_CONST_DEFN {
+    if (d->datum_) {
+        return d->datum_->primeMeridian();
+    }
+    return oneDatum(this)->primeMeridian();
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the ellipsoid associated with the GeodeticReferenceFrame
+ * or with one of the GeodeticReferenceFrame of the datumEnsemble().
+ *
+ * @return the PrimeMeridian.
+ */
+const datum::EllipsoidNNPtr &GeodeticCRS::ellipsoid() PROJ_CONST_DEFN {
+    if (d->datum_) {
+        return d->datum_->ellipsoid();
+    }
+    return oneDatum(this)->ellipsoid();
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the velocity model associated with the CRS.
+ *
+ * @return a velocity model. might be null.
+ */
+const std::vector<operation::PointMotionOperationNNPtr> &
+GeodeticCRS::velocityModel() PROJ_CONST_DEFN {
+    return d->velocityModel;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return whether the CRS is a geocentric one.
+ *
+ * A geocentric CRS is a geodetic CRS that has a Cartesian coordinate system
+ * with three axis, whose direction is respectively
+ * cs::AxisDirection::GEOCENTRIC_X,
+ * cs::AxisDirection::GEOCENTRIC_Y and cs::AxisDirection::GEOCENTRIC_Z.
+ *
+ * @return true if the CRS is a geocentric CRS.
+ */
+bool GeodeticCRS::isGeocentric() PROJ_CONST_DEFN {
+    const auto &cs = coordinateSystem();
+    const auto &axisList = cs->axisList();
+    return axisList.size() == 3 &&
+           dynamic_cast<cs::CartesianCS *>(cs.get()) != nullptr &&
+           &axisList[0]->direction() == &cs::AxisDirection::GEOCENTRIC_X &&
+           &axisList[1]->direction() == &cs::AxisDirection::GEOCENTRIC_Y &&
+           &axisList[2]->direction() == &cs::AxisDirection::GEOCENTRIC_Z;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a GeodeticCRS from a datum::GeodeticReferenceFrame and a
+ * cs::SphericalCS.
+ *
+ * @param properties See \ref general_properties.
+ * At minimum the name should be defined.
+ * @param datum The datum of the CRS.
+ * @param cs a SphericalCS.
+ * @return new GeodeticCRS.
+ */
+GeodeticCRSNNPtr
+GeodeticCRS::create(const util::PropertyMap &properties,
+                    const datum::GeodeticReferenceFrameNNPtr &datum,
+                    const cs::SphericalCSNNPtr &cs) {
+    return create(properties, datum.as_nullable(), nullptr, cs);
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a GeodeticCRS from a datum::GeodeticReferenceFrame or
+ * datum::DatumEnsemble and a cs::SphericalCS.
+ *
+ * One and only one of datum or datumEnsemble should be set to a non-null value.
+ *
+ * @param properties See \ref general_properties.
+ * At minimum the name should be defined.
+ * @param datum The datum of the CRS, or nullptr
+ * @param datumEnsemble The datum ensemble of the CRS, or nullptr.
+ * @param cs a SphericalCS.
+ * @return new GeodeticCRS.
+ */
+GeodeticCRSNNPtr
+GeodeticCRS::create(const util::PropertyMap &properties,
+                    const datum::GeodeticReferenceFramePtr &datum,
+                    const datum::DatumEnsemblePtr &datumEnsemble,
+                    const cs::SphericalCSNNPtr &cs) {
+    auto crs(
+        GeodeticCRS::nn_make_shared<GeodeticCRS>(datum, datumEnsemble, cs));
+    crs->assignSelf(crs);
+    crs->setProperties(properties);
+    properties.getStringValue("EXTENSION_PROJ4",
+                              crs->CRS::getPrivate()->extensionProj4_);
+
+    return crs;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a GeodeticCRS from a datum::GeodeticReferenceFrame and a
+ * cs::CartesianCS.
+ *
+ * @param properties See \ref general_properties.
+ * At minimum the name should be defined.
+ * @param datum The datum of the CRS.
+ * @param cs a CartesianCS.
+ * @return new GeodeticCRS.
+ */
+GeodeticCRSNNPtr
+GeodeticCRS::create(const util::PropertyMap &properties,
+                    const datum::GeodeticReferenceFrameNNPtr &datum,
+                    const cs::CartesianCSNNPtr &cs) {
+    return create(properties, datum.as_nullable(), nullptr, cs);
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a GeodeticCRS from a datum::GeodeticReferenceFrame or
+ * datum::DatumEnsemble and a cs::CartesianCS.
+ *
+ * One and only one of datum or datumEnsemble should be set to a non-null value.
+ *
+ * @param properties See \ref general_properties.
+ * At minimum the name should be defined.
+ * @param datum The datum of the CRS, or nullptr
+ * @param datumEnsemble The datum ensemble of the CRS, or nullptr.
+ * @param cs a CartesianCS
+ * @return new GeodeticCRS.
+ */
+GeodeticCRSNNPtr
+GeodeticCRS::create(const util::PropertyMap &properties,
+                    const datum::GeodeticReferenceFramePtr &datum,
+                    const datum::DatumEnsemblePtr &datumEnsemble,
+                    const cs::CartesianCSNNPtr &cs) {
+    auto crs(
+        GeodeticCRS::nn_make_shared<GeodeticCRS>(datum, datumEnsemble, cs));
+    crs->assignSelf(crs);
+    crs->setProperties(properties);
+    properties.getStringValue("EXTENSION_PROJ4",
+                              crs->CRS::getPrivate()->extensionProj4_);
+    return crs;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void GeodeticCRS::_exportToWKT(io::WKTFormatter *formatter) const {
+    const bool isWKT2 = formatter->version() == io::WKTFormatter::Version::WKT2;
+    formatter->startNode(isWKT2 ? ((formatter->use2018Keywords() &&
+                                    dynamic_cast<const GeographicCRS *>(this))
+                                       ? io::WKTConstants::GEOGCRS
+                                       : io::WKTConstants::GEODCRS)
+                                : isGeocentric() ? io::WKTConstants::GEOCCS
+                                                 : io::WKTConstants::GEOGCS,
+                         !identifiers().empty());
+    auto l_name = nameStr();
+    const auto &cs = coordinateSystem();
+    const auto &axisList = cs->axisList();
+
+    if (formatter->useESRIDialect()) {
+        if (axisList.size() != 2) {
+            io::FormattingException::Throw(
+                "Only export of Geographic 2D CRS is supported in WKT1_ESRI");
+        }
+
+        if (l_name == "WGS 84") {
+            l_name = "GCS_WGS_1984";
+        } else {
+            bool aliasFound = false;
+            const auto &dbContext = formatter->databaseContext();
+            if (dbContext) {
+                auto l_alias = dbContext->getAliasFromOfficialName(
+                    l_name, "geodetic_crs", "ESRI");
+                if (!l_alias.empty()) {
+                    l_name = l_alias;
+                    aliasFound = true;
+                }
+            }
+            if (!aliasFound) {
+                l_name = io::WKTFormatter::morphNameToESRI(l_name);
+                if (!starts_with(l_name, "GCS_")) {
+                    l_name = "GCS_" + l_name;
+                }
+            }
+        }
+    }
+    if (!isWKT2 && !formatter->useESRIDialect() && isDeprecated()) {
+        l_name += " (deprecated)";
+    }
+    formatter->addQuotedString(l_name);
+
+    const auto &unit = axisList[0]->unit();
+    formatter->pushAxisAngularUnit(common::UnitOfMeasure::create(unit));
+    exportDatumOrDatumEnsembleToWkt(formatter);
+    primeMeridian()->_exportToWKT(formatter);
+    formatter->popAxisAngularUnit();
+    if (!isWKT2) {
+        unit._exportToWKT(formatter);
+    }
+
+    const auto oldAxisOutputRule = formatter->outputAxis();
+    if (oldAxisOutputRule ==
+            io::WKTFormatter::OutputAxisRule::WKT1_GDAL_EPSG_STYLE &&
+        isGeocentric()) {
+        formatter->setOutputAxis(io::WKTFormatter::OutputAxisRule::YES);
+    }
+    cs->_exportToWKT(formatter);
+    formatter->setOutputAxis(oldAxisOutputRule);
+
+    ObjectUsage::baseExportToWKT(formatter);
+
+    if (!isWKT2 && !formatter->useESRIDialect()) {
+        const auto &extensionProj4 = CRS::getPrivate()->extensionProj4_;
+        if (!extensionProj4.empty()) {
+            formatter->startNode(io::WKTConstants::EXTENSION, false);
+            formatter->addQuotedString("PROJ4");
+            formatter->addQuotedString(extensionProj4);
+            formatter->endNode();
+        }
+    }
+
+    formatter->endNode();
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void GeodeticCRS::addGeocentricUnitConversionIntoPROJString(
+    io::PROJStringFormatter *formatter) const {
+
+    const auto &axisList = coordinateSystem()->axisList();
+    const auto &unit = axisList[0]->unit();
+    if (!unit._isEquivalentTo(common::UnitOfMeasure::METRE,
+                              util::IComparable::Criterion::EQUIVALENT)) {
+        if (formatter->convention() ==
+            io::PROJStringFormatter::Convention::PROJ_4) {
+            io::FormattingException::Throw("GeodeticCRS::exportToPROJString(): "
+                                           "non-meter unit not supported for "
+                                           "PROJ.4");
+        }
+
+        formatter->addStep("unitconvert");
+        formatter->addParam("xy_in", "m");
+        formatter->addParam("z_in", "m");
+        {
+            auto projUnit = unit.exportToPROJString();
+            if (!projUnit.empty()) {
+                formatter->addParam("xy_out", projUnit);
+                formatter->addParam("z_out", projUnit);
+                return;
+            }
+        }
+
+        const auto &toSI = unit.conversionToSI();
+        formatter->addParam("xy_out", toSI);
+        formatter->addParam("z_out", toSI);
+    } else if (formatter->convention() ==
+               io::PROJStringFormatter::Convention::PROJ_4) {
+        formatter->addParam("units", "m");
+    }
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void GeodeticCRS::_exportToPROJString(
+    io::PROJStringFormatter *formatter) const // throw(io::FormattingException)
+{
+    if (formatter->convention() ==
+        io::PROJStringFormatter::Convention::PROJ_4) {
+        const auto &extensionProj4 = CRS::getPrivate()->extensionProj4_;
+        if (!extensionProj4.empty()) {
+            formatter->ingestPROJString(extensionProj4);
+            formatter->addNoDefs(false);
+            return;
+        }
+    }
+
+    if (!isGeocentric()) {
+        io::FormattingException::Throw(
+            "GeodeticCRS::exportToPROJString() only "
+            "supports geocentric coordinate systems");
+    }
+
+    if (formatter->convention() ==
+        io::PROJStringFormatter::Convention::PROJ_4) {
+        formatter->addStep("geocent");
+    } else {
+        formatter->addStep("cart");
+    }
+    addDatumInfoToPROJString(formatter);
+    addGeocentricUnitConversionIntoPROJString(formatter);
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void GeodeticCRS::addDatumInfoToPROJString(
+    io::PROJStringFormatter *formatter) const // throw(io::FormattingException)
+{
+    const auto &TOWGS84Params = formatter->getTOWGS84Parameters();
+    bool datumWritten = false;
+    const auto &nadgrids = formatter->getHDatumExtension();
+    const auto &l_datum = datum();
+    if (formatter->convention() ==
+            io::PROJStringFormatter::Convention::PROJ_4 &&
+        l_datum && TOWGS84Params.empty() && nadgrids.empty()) {
+        if (l_datum->_isEquivalentTo(
+                datum::GeodeticReferenceFrame::EPSG_6326.get(),
+                util::IComparable::Criterion::EQUIVALENT)) {
+            datumWritten = true;
+            formatter->addParam("datum", "WGS84");
+        } else if (l_datum->_isEquivalentTo(
+                       datum::GeodeticReferenceFrame::EPSG_6267.get(),
+                       util::IComparable::Criterion::EQUIVALENT)) {
+            datumWritten = true;
+            formatter->addParam("datum", "NAD27");
+        } else if (l_datum->_isEquivalentTo(
+                       datum::GeodeticReferenceFrame::EPSG_6269.get(),
+                       util::IComparable::Criterion::EQUIVALENT)) {
+            datumWritten = true;
+            formatter->addParam("datum", "NAD83");
+        }
+    }
+    if (!datumWritten) {
+        ellipsoid()->_exportToPROJString(formatter);
+        primeMeridian()->_exportToPROJString(formatter);
+    }
+    if (TOWGS84Params.size() == 7) {
+        formatter->addParam("towgs84", TOWGS84Params);
+    }
+    if (!nadgrids.empty()) {
+        formatter->addParam("nadgrids", nadgrids);
+    }
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static util::IComparable::Criterion
+getStandardCriterion(util::IComparable::Criterion criterion) {
+    return criterion == util::IComparable::Criterion::
+                            EQUIVALENT_EXCEPT_AXIS_ORDER_GEOGCRS
+               ? util::IComparable::Criterion::EQUIVALENT
+               : criterion;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+bool GeodeticCRS::_isEquivalentTo(
+    const util::IComparable *other,
+    util::IComparable::Criterion criterion) const {
+    const auto standardCriterion = getStandardCriterion(criterion);
+    auto otherGeodCRS = dynamic_cast<const GeodeticCRS *>(other);
+    // TODO test velocityModel
+    return otherGeodCRS != nullptr &&
+           SingleCRS::baseIsEquivalentTo(other, standardCriterion);
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static util::PropertyMap createMapNameEPSGCode(const char *name, int code) {
+    return util::PropertyMap()
+        .set(common::IdentifiedObject::NAME_KEY, name)
+        .set(metadata::Identifier::CODESPACE_KEY, metadata::Identifier::EPSG)
+        .set(metadata::Identifier::CODE_KEY, code);
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+GeodeticCRSNNPtr GeodeticCRS::createEPSG_4978() {
+    return create(
+        createMapNameEPSGCode("WGS 84", 4978),
+        datum::GeodeticReferenceFrame::EPSG_6326,
+        cs::CartesianCS::createGeocentric(common::UnitOfMeasure::METRE));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Identify the CRS with reference CRSs.
+ *
+ * The candidate CRSs are either hard-coded, or looked in the database when
+ * authorityFactory is not null.
+ *
+ * The method returns a list of matching reference CRS, and the percentage
+ * (0-100) of confidence in the match.
+ * 100% means that the name of the reference entry
+ * perfectly matches the CRS name, and both are equivalent. In which case a
+ * single result is returned.
+ * 90% means that CRS are equivalent, but the names are not exactly the same.
+ * 70% means that CRS are equivalent (equivalent datum and coordinate system),
+ * but the names do not match at all.
+ * 60% means that ellipsoid, prime meridian and coordinate systems are
+ * equivalent, but the CRS and datum names do not match.
+ * 25% means that the CRS are not equivalent, but there is some similarity in
+ * the names.
+ *
+ * @param authorityFactory Authority factory (or null, but degraded
+ * functionality)
+ * @return a list of matching reference CRS, and the percentage (0-100) of
+ * confidence in the match.
+ */
+std::list<std::pair<GeodeticCRSNNPtr, int>>
+GeodeticCRS::identify(const io::AuthorityFactoryPtr &authorityFactory) const {
+    typedef std::pair<GeodeticCRSNNPtr, int> Pair;
+    std::list<Pair> res;
+    const auto &thisName(nameStr());
+
+    const bool l_implicitCS = CRS::getPrivate()->implicitCS_;
+    const auto crsCriterion =
+        l_implicitCS
+            ? util::IComparable::Criterion::EQUIVALENT_EXCEPT_AXIS_ORDER_GEOGCRS
+            : util::IComparable::Criterion::EQUIVALENT;
+
+    const GeographicCRSNNPtr candidatesCRS[] = {GeographicCRS::EPSG_4326,
+                                                GeographicCRS::EPSG_4267,
+                                                GeographicCRS::EPSG_4269};
+    for (const auto &crs : candidatesCRS) {
+        const bool nameEquivalent = metadata::Identifier::isEquivalentName(
+            thisName.c_str(), crs->nameStr().c_str());
+        const bool nameEqual = thisName == crs->nameStr();
+        const bool isEq = _isEquivalentTo(crs.get(), crsCriterion);
+        if (nameEquivalent && isEq && (!authorityFactory || nameEqual)) {
+            res.emplace_back(util::nn_static_pointer_cast<GeodeticCRS>(crs),
+                             nameEqual ? 100 : 90);
+            return res;
+        } else if (nameEqual && !isEq && !authorityFactory) {
+            res.emplace_back(util::nn_static_pointer_cast<GeodeticCRS>(crs),
+                             25);
+            return res;
+        } else if (isEq && !authorityFactory) {
+            res.emplace_back(util::nn_static_pointer_cast<GeodeticCRS>(crs),
+                             70);
+            return res;
+        }
+    }
+
+    std::string geodetic_crs_type;
+    if (isGeocentric()) {
+        geodetic_crs_type = "geocentric";
+    } else {
+        auto geogCRS = dynamic_cast<const GeographicCRS *>(this);
+        if (geogCRS) {
+            if (coordinateSystem()->axisList().size() == 2) {
+                geodetic_crs_type = "geographic 2D";
+            } else {
+                geodetic_crs_type = "geographic 3D";
+            }
+        }
+    }
+
+    if (authorityFactory) {
+
+        const auto &thisDatum(datum());
+
+        auto searchByDatum = [this, &authorityFactory, &res, &thisDatum,
+                              &geodetic_crs_type, crsCriterion]() {
+            for (const auto &id : thisDatum->identifiers()) {
+                try {
+                    auto tempRes = authorityFactory->createGeodeticCRSFromDatum(
+                        *id->codeSpace(), id->code(), geodetic_crs_type);
+                    for (const auto &crs : tempRes) {
+                        if (_isEquivalentTo(crs.get(), crsCriterion)) {
+                            res.emplace_back(crs, 70);
+                        }
+                    }
+                } catch (const std::exception &) {
+                }
+            }
+        };
+
+        const auto &thisEllipsoid(ellipsoid());
+        auto searchByEllipsoid = [this, &authorityFactory, &res, &thisDatum,
+                                  &thisEllipsoid, &geodetic_crs_type,
+                                  l_implicitCS]() {
+            const auto ellipsoids =
+                thisEllipsoid->identifiers().empty()
+                    ? authorityFactory->createEllipsoidFromExisting(
+                          thisEllipsoid)
+                    : std::list<datum::EllipsoidNNPtr>{thisEllipsoid};
+            for (const auto &ellps : ellipsoids) {
+                for (const auto &id : ellps->identifiers()) {
+                    try {
+                        auto tempRes =
+                            authorityFactory->createGeodeticCRSFromEllipsoid(
+                                *id->codeSpace(), id->code(),
+                                geodetic_crs_type);
+                        for (const auto &crs : tempRes) {
+                            const auto &crsDatum(crs->datum());
+                            if (crsDatum &&
+                                crsDatum->ellipsoid()->_isEquivalentTo(
+                                    ellps.get(),
+                                    util::IComparable::Criterion::EQUIVALENT) &&
+                                crsDatum->primeMeridian()->_isEquivalentTo(
+                                    thisDatum->primeMeridian().get(),
+                                    util::IComparable::Criterion::EQUIVALENT) &&
+                                (!l_implicitCS ||
+                                 coordinateSystem()->_isEquivalentTo(
+                                     crs->coordinateSystem().get(),
+                                     util::IComparable::Criterion::
+                                         EQUIVALENT))) {
+                                res.emplace_back(crs, 60);
+                            }
+                        }
+                    } catch (const std::exception &) {
+                    }
+                }
+            }
+        };
+
+        const bool unsignificantName = thisName.empty() ||
+                                       ci_equal(thisName, "unknown") ||
+                                       ci_equal(thisName, "unnamed");
+
+        if (unsignificantName) {
+            if (thisDatum) {
+                if (!thisDatum->identifiers().empty()) {
+                    searchByDatum();
+                } else {
+                    searchByEllipsoid();
+                }
+            }
+        } else if (!identifiers().empty()) {
+            // If the CRS has already an id, check in the database for the
+            // official object, and verify that they are equivalent.
+            for (const auto &id : identifiers()) {
+                try {
+                    auto crs = io::AuthorityFactory::create(
+                                   authorityFactory->databaseContext(),
+                                   *id->codeSpace())
+                                   ->createGeodeticCRS(id->code());
+                    bool match = _isEquivalentTo(crs.get(), crsCriterion);
+                    res.emplace_back(crs, match ? 100 : 25);
+                    return res;
+                } catch (const std::exception &) {
+                }
+            }
+        } else {
+            bool gotAbove25Pct = false;
+            for (int ipass = 0; ipass < 2; ipass++) {
+                const bool approximateMatch = ipass == 1;
+                auto objects = authorityFactory->createObjectsFromName(
+                    thisName, {io::AuthorityFactory::ObjectType::GEODETIC_CRS},
+                    approximateMatch);
+                for (const auto &obj : objects) {
+                    auto crs = util::nn_dynamic_pointer_cast<GeodeticCRS>(obj);
+                    assert(crs);
+                    auto crsNN = NN_NO_CHECK(crs);
+                    if (_isEquivalentTo(crs.get(), crsCriterion)) {
+                        if (crs->nameStr() == thisName) {
+                            res.clear();
+                            res.emplace_back(crsNN, 100);
+                            return res;
+                        }
+                        const bool eqName =
+                            metadata::Identifier::isEquivalentName(
+                                thisName.c_str(), crs->nameStr().c_str());
+                        res.emplace_back(crsNN, eqName ? 90 : 70);
+                        gotAbove25Pct = true;
+                    } else {
+                        res.emplace_back(crsNN, 25);
+                    }
+                }
+                if (!res.empty()) {
+                    break;
+                }
+            }
+            if (!gotAbove25Pct && thisDatum) {
+                if (!thisDatum->identifiers().empty()) {
+                    searchByDatum();
+                } else {
+                    searchByEllipsoid();
+                }
+            }
+        }
+
+        const auto &thisCS(coordinateSystem());
+        // Sort results
+        res.sort([&thisName, &thisDatum, &thisCS](const Pair &a,
+                                                  const Pair &b) {
+            // First consider confidence
+            if (a.second > b.second) {
+                return true;
+            }
+            if (a.second < b.second) {
+                return false;
+            }
+
+            // Then consider exact name matching
+            const auto &aName(a.first->nameStr());
+            const auto &bName(b.first->nameStr());
+            if (aName == thisName && bName != thisName) {
+                return true;
+            }
+            if (bName == thisName && aName != thisName) {
+                return false;
+            }
+
+            // Then datum matching
+            const auto &aDatum(a.first->datum());
+            const auto &bDatum(b.first->datum());
+            if (thisDatum && aDatum && bDatum) {
+                const auto thisEquivADatum(thisDatum->_isEquivalentTo(
+                    aDatum.get(), util::IComparable::Criterion::EQUIVALENT));
+                const auto thisEquivBDatum(thisDatum->_isEquivalentTo(
+                    bDatum.get(), util::IComparable::Criterion::EQUIVALENT));
+
+                if (thisEquivADatum && !thisEquivBDatum) {
+                    return true;
+                }
+                if (!thisEquivADatum && thisEquivBDatum) {
+                    return false;
+                }
+            }
+
+            // Then coordinate system matching
+            const auto &aCS(a.first->coordinateSystem());
+            const auto &bCS(b.first->coordinateSystem());
+            const auto thisEquivACs(thisCS->_isEquivalentTo(
+                aCS.get(), util::IComparable::Criterion::EQUIVALENT));
+            const auto thisEquivBCs(thisCS->_isEquivalentTo(
+                bCS.get(), util::IComparable::Criterion::EQUIVALENT));
+            if (thisEquivACs && !thisEquivBCs) {
+                return true;
+            }
+            if (!thisEquivACs && thisEquivBCs) {
+                return false;
+            }
+
+            // Then dimension of the coordinate system matching
+            const auto thisCSAxisListSize = thisCS->axisList().size();
+            const auto aCSAxistListSize = aCS->axisList().size();
+            const auto bCSAxistListSize = bCS->axisList().size();
+            if (thisCSAxisListSize == aCSAxistListSize &&
+                thisCSAxisListSize != bCSAxistListSize) {
+                return true;
+            }
+            if (thisCSAxisListSize != aCSAxistListSize &&
+                thisCSAxisListSize == bCSAxistListSize) {
+                return false;
+            }
+
+            if (aDatum && bDatum) {
+                // Favor the CRS whole ellipsoid names matches the ellipsoid
+                // name (WGS84...)
+                const bool aEllpsNameEqCRSName =
+                    metadata::Identifier::isEquivalentName(
+                        aDatum->ellipsoid()->nameStr().c_str(),
+                        a.first->nameStr().c_str());
+                const bool bEllpsNameEqCRSName =
+                    metadata::Identifier::isEquivalentName(
+                        bDatum->ellipsoid()->nameStr().c_str(),
+                        b.first->nameStr().c_str());
+                if (aEllpsNameEqCRSName && !bEllpsNameEqCRSName) {
+                    return true;
+                }
+                if (bEllpsNameEqCRSName && !aEllpsNameEqCRSName) {
+                    return false;
+                }
+            }
+
+            // Arbitrary final sorting criterion
+            return aName < bName;
+        });
+
+        // If there are results with 90% confidence, only keep those
+        if (res.size() >= 2 && res.front().second == 90) {
+            std::list<Pair> newRes;
+            for (const auto &pair : res) {
+                if (pair.second == 90) {
+                    newRes.push_back(pair);
+                } else {
+                    break;
+                }
+            }
+            return newRes;
+        }
+    }
+    return res;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+std::list<std::pair<CRSNNPtr, int>>
+GeodeticCRS::_identify(const io::AuthorityFactoryPtr &authorityFactory) const {
+    typedef std::pair<CRSNNPtr, int> Pair;
+    std::list<Pair> res;
+    auto resTemp = identify(authorityFactory);
+    for (const auto &pair : resTemp) {
+        res.emplace_back(pair.first, pair.second);
+    }
+    return res;
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct GeographicCRS::Private {
+    cs::EllipsoidalCSNNPtr coordinateSystem_;
+    explicit Private(const cs::EllipsoidalCSNNPtr &csIn)
+        : coordinateSystem_(csIn) {}
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+GeographicCRS::GeographicCRS(const datum::GeodeticReferenceFramePtr &datumIn,
+                             const datum::DatumEnsemblePtr &datumEnsembleIn,
+                             const cs::EllipsoidalCSNNPtr &csIn)
+    : SingleCRS(datumIn, datumEnsembleIn, csIn),
+      GeodeticCRS(datumIn,
+                  checkEnsembleForGeodeticCRS(datumIn, datumEnsembleIn), csIn),
+      d(internal::make_unique<Private>(csIn)) {}
+
+// ---------------------------------------------------------------------------
+
+GeographicCRS::GeographicCRS(const GeographicCRS &other)
+    : SingleCRS(other), GeodeticCRS(other),
+      d(internal::make_unique<Private>(*other.d)) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+GeographicCRS::~GeographicCRS() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+CRSNNPtr GeographicCRS::_shallowClone() const {
+    auto crs(GeographicCRS::nn_make_shared<GeographicCRS>(*this));
+    crs->assignSelf(crs);
+    return crs;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the cs::EllipsoidalCS associated with the CRS.
+ *
+ * @return a EllipsoidalCS.
+ */
+const cs::EllipsoidalCSNNPtr &
+GeographicCRS::coordinateSystem() PROJ_CONST_DEFN {
+    return d->coordinateSystem_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a GeographicCRS from a datum::GeodeticReferenceFrameNNPtr
+ * and a
+ * cs::EllipsoidalCS.
+ *
+ * @param properties See \ref general_properties.
+ * At minimum the name should be defined.
+ * @param datum The datum of the CRS.
+ * @param cs a EllipsoidalCS.
+ * @return new GeographicCRS.
+ */
+GeographicCRSNNPtr
+GeographicCRS::create(const util::PropertyMap &properties,
+                      const datum::GeodeticReferenceFrameNNPtr &datum,
+                      const cs::EllipsoidalCSNNPtr &cs) {
+    return create(properties, datum.as_nullable(), nullptr, cs);
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a GeographicCRS from a datum::GeodeticReferenceFramePtr
+ * or
+ * datum::DatumEnsemble and a
+ * cs::EllipsoidalCS.
+ *
+ * One and only one of datum or datumEnsemble should be set to a non-null value.
+ *
+ * @param properties See \ref general_properties.
+ * At minimum the name should be defined.
+ * @param datum The datum of the CRS, or nullptr
+ * @param datumEnsemble The datum ensemble of the CRS, or nullptr.
+ * @param cs a EllipsoidalCS.
+ * @return new GeographicCRS.
+ */
+GeographicCRSNNPtr
+GeographicCRS::create(const util::PropertyMap &properties,
+                      const datum::GeodeticReferenceFramePtr &datum,
+                      const datum::DatumEnsemblePtr &datumEnsemble,
+                      const cs::EllipsoidalCSNNPtr &cs) {
+    GeographicCRSNNPtr crs(
+        GeographicCRS::nn_make_shared<GeographicCRS>(datum, datumEnsemble, cs));
+    crs->assignSelf(crs);
+    crs->setProperties(properties);
+    properties.getStringValue("EXTENSION_PROJ4",
+                              crs->CRS::getPrivate()->extensionProj4_);
+    crs->CRS::getPrivate()->setImplicitCS(properties);
+    return crs;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+/** \brief Return whether the current GeographicCRS is the 2D part of the
+ * other 3D GeographicCRS.
+ */
+bool GeographicCRS::is2DPartOf3D(util::nn<const GeographicCRS *> other)
+    PROJ_CONST_DEFN {
+    const auto &axis = d->coordinateSystem_->axisList();
+    const auto &otherAxis = other->d->coordinateSystem_->axisList();
+    if (!(axis.size() == 2 && otherAxis.size() == 3)) {
+        return false;
+    }
+    const auto &firstAxis = axis[0];
+    const auto &secondAxis = axis[1];
+    const auto &otherFirstAxis = otherAxis[0];
+    const auto &otherSecondAxis = otherAxis[1];
+    if (!(firstAxis->_isEquivalentTo(otherFirstAxis.get()) &&
+          secondAxis->_isEquivalentTo(otherSecondAxis.get()))) {
+        return false;
+    }
+    const auto &thisDatum = GeodeticCRS::getPrivate()->datum_;
+    const auto &otherDatum = other->GeodeticCRS::getPrivate()->datum_;
+    if (thisDatum && otherDatum) {
+        return thisDatum->_isEquivalentTo(otherDatum.get());
+    }
+    return false;
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+bool GeographicCRS::_isEquivalentTo(
+    const util::IComparable *other,
+    util::IComparable::Criterion criterion) const {
+    auto otherGeogCRS = dynamic_cast<const GeographicCRS *>(other);
+    if (otherGeogCRS == nullptr) {
+        return false;
+    }
+    const auto standardCriterion = getStandardCriterion(criterion);
+    if (GeodeticCRS::_isEquivalentTo(other, standardCriterion)) {
+        return true;
+    }
+    if (criterion !=
+        util::IComparable::Criterion::EQUIVALENT_EXCEPT_AXIS_ORDER_GEOGCRS) {
+        return false;
+    }
+    const auto axisOrder = coordinateSystem()->axisOrder();
+    if (axisOrder == cs::EllipsoidalCS::AxisOrder::LONG_EAST_LAT_NORTH ||
+        axisOrder == cs::EllipsoidalCS::AxisOrder::LAT_NORTH_LONG_EAST) {
+        const auto &unit = coordinateSystem()->axisList()[0]->unit();
+        return GeographicCRS::create(
+                   util::PropertyMap().set(common::IdentifiedObject::NAME_KEY,
+                                           nameStr()),
+                   datum(), datumEnsemble(),
+                   axisOrder ==
+                           cs::EllipsoidalCS::AxisOrder::LONG_EAST_LAT_NORTH
+                       ? cs::EllipsoidalCS::createLatitudeLongitude(unit)
+                       : cs::EllipsoidalCS::createLongitudeLatitude(unit))
+            ->GeodeticCRS::_isEquivalentTo(other, standardCriterion);
+    }
+    return false;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+GeographicCRSNNPtr GeographicCRS::createEPSG_4267() {
+    return create(createMapNameEPSGCode("NAD27", 4267),
+                  datum::GeodeticReferenceFrame::EPSG_6267,
+                  cs::EllipsoidalCS::createLatitudeLongitude(
+                      common::UnitOfMeasure::DEGREE));
+}
+
+// ---------------------------------------------------------------------------
+
+GeographicCRSNNPtr GeographicCRS::createEPSG_4269() {
+    return create(createMapNameEPSGCode("NAD83", 4269),
+                  datum::GeodeticReferenceFrame::EPSG_6269,
+                  cs::EllipsoidalCS::createLatitudeLongitude(
+                      common::UnitOfMeasure::DEGREE));
+}
+
+// ---------------------------------------------------------------------------
+
+GeographicCRSNNPtr GeographicCRS::createEPSG_4326() {
+    return create(createMapNameEPSGCode("WGS 84", 4326),
+                  datum::GeodeticReferenceFrame::EPSG_6326,
+                  cs::EllipsoidalCS::createLatitudeLongitude(
+                      common::UnitOfMeasure::DEGREE));
+}
+
+// ---------------------------------------------------------------------------
+
+GeographicCRSNNPtr GeographicCRS::createOGC_CRS84() {
+    util::PropertyMap propertiesCRS;
+    propertiesCRS
+        .set(metadata::Identifier::CODESPACE_KEY, metadata::Identifier::OGC)
+        .set(metadata::Identifier::CODE_KEY, "CRS84")
+        .set(common::IdentifiedObject::NAME_KEY, "WGS 84 (CRS84)");
+    return create(propertiesCRS, datum::GeodeticReferenceFrame::EPSG_6326,
+                  cs::EllipsoidalCS::createLongitudeLatitude( // Long Lat !
+                      common::UnitOfMeasure::DEGREE));
+}
+
+// ---------------------------------------------------------------------------
+
+GeographicCRSNNPtr GeographicCRS::createEPSG_4979() {
+    return create(
+        createMapNameEPSGCode("WGS 84", 4979),
+        datum::GeodeticReferenceFrame::EPSG_6326,
+        cs::EllipsoidalCS::createLatitudeLongitudeEllipsoidalHeight(
+            common::UnitOfMeasure::DEGREE, common::UnitOfMeasure::METRE));
+}
+
+// ---------------------------------------------------------------------------
+
+GeographicCRSNNPtr GeographicCRS::createEPSG_4807() {
+    auto ellps(datum::Ellipsoid::createFlattenedSphere(
+        createMapNameEPSGCode("Clarke 1880 (IGN)", 7011),
+        common::Length(6378249.2), common::Scale(293.4660212936269)));
+
+    auto cs(cs::EllipsoidalCS::createLatitudeLongitude(
+        common::UnitOfMeasure::GRAD));
+
+    auto datum(datum::GeodeticReferenceFrame::create(
+        createMapNameEPSGCode("Nouvelle Triangulation Francaise (Paris)", 6807),
+        ellps, util::optional<std::string>(), datum::PrimeMeridian::PARIS));
+
+    return create(createMapNameEPSGCode("NTF (Paris)", 4807), datum, cs);
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void GeographicCRS::addAngularUnitConvertAndAxisSwap(
+    io::PROJStringFormatter *formatter) const {
+    const auto &axisList = coordinateSystem()->axisList();
+
+    if (formatter->convention() ==
+        io::PROJStringFormatter::Convention::PROJ_5) {
+
+        formatter->addStep("unitconvert");
+        formatter->addParam("xy_in", "rad");
+        if (axisList.size() == 3 && !formatter->omitZUnitConversion()) {
+            formatter->addParam("z_in", "m");
+        }
+        {
+            const auto &unitHoriz = axisList[0]->unit();
+            const auto projUnit = unitHoriz.exportToPROJString();
+            if (projUnit.empty()) {
+                formatter->addParam("xy_out", unitHoriz.conversionToSI());
+            } else {
+                formatter->addParam("xy_out", projUnit);
+            }
+        }
+        if (axisList.size() == 3 && !formatter->omitZUnitConversion()) {
+            const auto &unitZ = axisList[2]->unit();
+            auto projVUnit = unitZ.exportToPROJString();
+            if (projVUnit.empty()) {
+                formatter->addParam("z_out", unitZ.conversionToSI());
+            } else {
+                formatter->addParam("z_out", projVUnit);
+            }
+        }
+
+        const char *order[2] = {nullptr, nullptr};
+        const char *one = "1";
+        const char *two = "2";
+        for (int i = 0; i < 2; i++) {
+            const auto &dir = axisList[i]->direction();
+            if (&dir == &cs::AxisDirection::WEST) {
+                order[i] = "-1";
+            } else if (&dir == &cs::AxisDirection::EAST) {
+                order[i] = one;
+            } else if (&dir == &cs::AxisDirection::SOUTH) {
+                order[i] = "-2";
+            } else if (&dir == &cs::AxisDirection::NORTH) {
+                order[i] = two;
+            }
+        }
+        if (order[0] && order[1] && (order[0] != one || order[1] != two)) {
+            formatter->addStep("axisswap");
+            char orderStr[10];
+            strcpy(orderStr, order[0]);
+            strcat(orderStr, ",");
+            strcat(orderStr, order[1]);
+            formatter->addParam("order", orderStr);
+        }
+    }
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void GeographicCRS::_exportToPROJString(
+    io::PROJStringFormatter *formatter) const // throw(io::FormattingException)
+{
+    if (formatter->convention() ==
+        io::PROJStringFormatter::Convention::PROJ_4) {
+        const auto &extensionProj4 = CRS::getPrivate()->extensionProj4_;
+        if (!extensionProj4.empty()) {
+            formatter->ingestPROJString(extensionProj4);
+            formatter->addNoDefs(false);
+            return;
+        }
+    }
+
+    if (!formatter->omitProjLongLatIfPossible() ||
+        primeMeridian()->longitude().getSIValue() != 0.0 ||
+        !formatter->getTOWGS84Parameters().empty() ||
+        !formatter->getHDatumExtension().empty()) {
+        formatter->addStep("longlat");
+        addDatumInfoToPROJString(formatter);
+    }
+
+    addAngularUnitConvertAndAxisSwap(formatter);
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct VerticalCRS::Private {
+    std::vector<operation::TransformationNNPtr> geoidModel{};
+    std::vector<operation::PointMotionOperationNNPtr> velocityModel{};
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static const datum::DatumEnsemblePtr &
+checkEnsembleForVerticalCRS(const datum::VerticalReferenceFramePtr &datumIn,
+                            const datum::DatumEnsemblePtr &ensemble) {
+    const char *msg = "One of Datum or DatumEnsemble should be defined";
+    if (datumIn) {
+        if (!ensemble) {
+            return ensemble;
+        }
+        msg = "Datum and DatumEnsemble should not be defined";
+    } else if (ensemble) {
+        const auto &datums = ensemble->datums();
+        assert(!datums.empty());
+        auto grfFirst =
+            dynamic_cast<datum::VerticalReferenceFrame *>(datums[0].get());
+        if (grfFirst) {
+            return ensemble;
+        }
+        msg = "Ensemble should contain VerticalReferenceFrame";
+    }
+    throw util::Exception(msg);
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+VerticalCRS::VerticalCRS(const datum::VerticalReferenceFramePtr &datumIn,
+                         const datum::DatumEnsemblePtr &datumEnsembleIn,
+                         const cs::VerticalCSNNPtr &csIn)
+    : SingleCRS(datumIn, checkEnsembleForVerticalCRS(datumIn, datumEnsembleIn),
+                csIn),
+      d(internal::make_unique<Private>()) {}
+
+// ---------------------------------------------------------------------------
+
+VerticalCRS::VerticalCRS(const VerticalCRS &other)
+    : SingleCRS(other), d(internal::make_unique<Private>(*other.d)) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+VerticalCRS::~VerticalCRS() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+CRSNNPtr VerticalCRS::_shallowClone() const {
+    auto crs(VerticalCRS::nn_make_shared<VerticalCRS>(*this));
+    crs->assignSelf(crs);
+    return crs;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the datum::VerticalReferenceFrame associated with the CRS.
+ *
+ * @return a VerticalReferenceFrame.
+ */
+const datum::VerticalReferenceFramePtr VerticalCRS::datum() const {
+    return std::static_pointer_cast<datum::VerticalReferenceFrame>(
+        SingleCRS::getPrivate()->datum);
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the geoid model associated with the CRS.
+ *
+ * Geoid height model or height correction model linked to a geoid-based
+ * vertical CRS.
+ *
+ * @return a geoid model. might be null
+ */
+const std::vector<operation::TransformationNNPtr> &
+VerticalCRS::geoidModel() PROJ_CONST_DEFN {
+    return d->geoidModel;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the velocity model associated with the CRS.
+ *
+ * @return a velocity model. might be null.
+ */
+const std::vector<operation::PointMotionOperationNNPtr> &
+VerticalCRS::velocityModel() PROJ_CONST_DEFN {
+    return d->velocityModel;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the cs::VerticalCS associated with the CRS.
+ *
+ * @return a VerticalCS.
+ */
+const cs::VerticalCSNNPtr VerticalCRS::coordinateSystem() const {
+    return util::nn_static_pointer_cast<cs::VerticalCS>(
+        SingleCRS::getPrivate()->coordinateSystem);
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void VerticalCRS::_exportToWKT(io::WKTFormatter *formatter) const {
+    const bool isWKT2 = formatter->version() == io::WKTFormatter::Version::WKT2;
+    formatter->startNode(isWKT2 ? io::WKTConstants::VERTCRS
+                                : io::WKTConstants::VERT_CS,
+                         !identifiers().empty());
+    formatter->addQuotedString(nameStr());
+    exportDatumOrDatumEnsembleToWkt(formatter);
+    const auto &cs = SingleCRS::getPrivate()->coordinateSystem;
+    const auto &axisList = cs->axisList();
+    if (!isWKT2) {
+        axisList[0]->unit()._exportToWKT(formatter);
+    }
+
+    const auto oldAxisOutputRule = formatter->outputAxis();
+    if (oldAxisOutputRule ==
+        io::WKTFormatter::OutputAxisRule::WKT1_GDAL_EPSG_STYLE) {
+        formatter->setOutputAxis(io::WKTFormatter::OutputAxisRule::YES);
+    }
+    cs->_exportToWKT(formatter);
+    formatter->setOutputAxis(oldAxisOutputRule);
+
+    ObjectUsage::baseExportToWKT(formatter);
+    formatter->endNode();
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+void VerticalCRS::_exportToPROJString(
+    io::PROJStringFormatter *formatter) const // throw(io::FormattingException)
+{
+    auto geoidgrids = formatter->getVDatumExtension();
+    if (!geoidgrids.empty()) {
+        formatter->addParam("geoidgrids", geoidgrids);
+    }
+
+    auto &axisList = coordinateSystem()->axisList();
+    if (!axisList.empty()) {
+        auto projUnit = axisList[0]->unit().exportToPROJString();
+        if (projUnit.empty()) {
+            formatter->addParam("vto_meter",
+                                axisList[0]->unit().conversionToSI());
+        } else {
+            formatter->addParam("vunits", projUnit);
+        }
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void VerticalCRS::addLinearUnitConvert(
+    io::PROJStringFormatter *formatter) const {
+    auto &axisList = coordinateSystem()->axisList();
+
+    if (formatter->convention() ==
+        io::PROJStringFormatter::Convention::PROJ_5) {
+        if (!axisList.empty()) {
+            auto projUnit = axisList[0]->unit().exportToPROJString();
+            if (axisList[0]->unit().conversionToSI() != 1.0) {
+                formatter->addStep("unitconvert");
+                formatter->addParam("z_in", "m");
+                auto projVUnit = axisList[0]->unit().exportToPROJString();
+                if (projVUnit.empty()) {
+                    formatter->addParam("z_out",
+                                        axisList[0]->unit().conversionToSI());
+                } else {
+                    formatter->addParam("z_out", projVUnit);
+                }
+            }
+        }
+    }
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a VerticalCRS from a datum::VerticalReferenceFrame and a
+ * cs::VerticalCS.
+ *
+ * @param properties See \ref general_properties.
+ * At minimum the name should be defined.
+ * @param datumIn The datum of the CRS.
+ * @param csIn a VerticalCS.
+ * @return new VerticalCRS.
+ */
+VerticalCRSNNPtr
+VerticalCRS::create(const util::PropertyMap &properties,
+                    const datum::VerticalReferenceFrameNNPtr &datumIn,
+                    const cs::VerticalCSNNPtr &csIn) {
+    return create(properties, datumIn.as_nullable(), nullptr, csIn);
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a VerticalCRS from a datum::VerticalReferenceFrame or
+ * datum::DatumEnsemble and a cs::VerticalCS.
+ *
+ * One and only one of datum or datumEnsemble should be set to a non-null value.
+ *
+ * @param properties See \ref general_properties.
+ * At minimum the name should be defined.
+ * @param datumIn The datum of the CRS, or nullptr
+ * @param datumEnsembleIn The datum ensemble of the CRS, or nullptr.
+ * @param csIn a VerticalCS.
+ * @return new VerticalCRS.
+ */
+VerticalCRSNNPtr
+VerticalCRS::create(const util::PropertyMap &properties,
+                    const datum::VerticalReferenceFramePtr &datumIn,
+                    const datum::DatumEnsemblePtr &datumEnsembleIn,
+                    const cs::VerticalCSNNPtr &csIn) {
+    auto crs(VerticalCRS::nn_make_shared<VerticalCRS>(datumIn, datumEnsembleIn,
+                                                      csIn));
+    crs->assignSelf(crs);
+    crs->setProperties(properties);
+    return crs;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+bool VerticalCRS::_isEquivalentTo(
+    const util::IComparable *other,
+    util::IComparable::Criterion criterion) const {
+    auto otherVertCRS = dynamic_cast<const VerticalCRS *>(other);
+    // TODO test geoidModel and velocityModel
+    return otherVertCRS != nullptr &&
+           SingleCRS::baseIsEquivalentTo(other, criterion);
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Identify the CRS with reference CRSs.
+ *
+ * The candidate CRSs are looked in the database when
+ * authorityFactory is not null.
+ *
+ * The method returns a list of matching reference CRS, and the percentage
+ * (0-100) of confidence in the match.
+ * 100% means that the name of the reference entry
+ * perfectly matches the CRS name, and both are equivalent. In which case a
+ * single result is returned.
+ * 90% means that CRS are equivalent, but the names are not exactly the same.
+ * 70% means that CRS are equivalent (equivalent datum and coordinate system),
+ * but the names do not match at all.
+ * 25% means that the CRS are not equivalent, but there is some similarity in
+ * the names.
+ *
+ * @param authorityFactory Authority factory (if null, will return an empty
+ * list)
+ * @return a list of matching reference CRS, and the percentage (0-100) of
+ * confidence in the match.
+ */
+std::list<std::pair<VerticalCRSNNPtr, int>>
+VerticalCRS::identify(const io::AuthorityFactoryPtr &authorityFactory) const {
+    typedef std::pair<VerticalCRSNNPtr, int> Pair;
+    std::list<Pair> res;
+
+    const auto &thisName(nameStr());
+
+    if (authorityFactory) {
+
+        const bool unsignificantName = thisName.empty() ||
+                                       ci_equal(thisName, "unknown") ||
+                                       ci_equal(thisName, "unnamed");
+        if (!identifiers().empty()) {
+            // If the CRS has already an id, check in the database for the
+            // official object, and verify that they are equivalent.
+            for (const auto &id : identifiers()) {
+                try {
+                    auto crs = io::AuthorityFactory::create(
+                                   authorityFactory->databaseContext(),
+                                   *id->codeSpace())
+                                   ->createVerticalCRS(id->code());
+                    bool match = _isEquivalentTo(
+                        crs.get(), util::IComparable::Criterion::EQUIVALENT);
+                    res.emplace_back(crs, match ? 100 : 25);
+                    return res;
+                } catch (const std::exception &) {
+                }
+            }
+        } else if (!unsignificantName) {
+            for (int ipass = 0; ipass < 2; ipass++) {
+                const bool approximateMatch = ipass == 1;
+                auto objects = authorityFactory->createObjectsFromName(
+                    thisName, {io::AuthorityFactory::ObjectType::VERTICAL_CRS},
+                    approximateMatch);
+                for (const auto &obj : objects) {
+                    auto crs = util::nn_dynamic_pointer_cast<VerticalCRS>(obj);
+                    assert(crs);
+                    auto crsNN = NN_NO_CHECK(crs);
+                    if (_isEquivalentTo(
+                            crs.get(),
+                            util::IComparable::Criterion::EQUIVALENT)) {
+                        if (crs->nameStr() == thisName) {
+                            res.clear();
+                            res.emplace_back(crsNN, 100);
+                            return res;
+                        }
+                        res.emplace_back(crsNN, 90);
+                    } else {
+                        res.emplace_back(crsNN, 25);
+                    }
+                }
+                if (!res.empty()) {
+                    break;
+                }
+            }
+        }
+
+        // Sort results
+        res.sort([&thisName](const Pair &a, const Pair &b) {
+            // First consider confidence
+            if (a.second > b.second) {
+                return true;
+            }
+            if (a.second < b.second) {
+                return false;
+            }
+
+            // Then consider exact name matching
+            const auto &aName(a.first->nameStr());
+            const auto &bName(b.first->nameStr());
+            if (aName == thisName && bName != thisName) {
+                return true;
+            }
+            if (bName == thisName && aName != thisName) {
+                return false;
+            }
+
+            // Arbitrary final sorting criterion
+            return aName < bName;
+        });
+
+        // Keep only results of the highest confidence
+        if (res.size() >= 2) {
+            const auto highestConfidence = res.front().second;
+            std::list<Pair> newRes;
+            for (const auto &pair : res) {
+                if (pair.second == highestConfidence) {
+                    newRes.push_back(pair);
+                } else {
+                    break;
+                }
+            }
+            return newRes;
+        }
+    }
+
+    return res;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+std::list<std::pair<CRSNNPtr, int>>
+VerticalCRS::_identify(const io::AuthorityFactoryPtr &authorityFactory) const {
+    typedef std::pair<CRSNNPtr, int> Pair;
+    std::list<Pair> res;
+    auto resTemp = identify(authorityFactory);
+    for (const auto &pair : resTemp) {
+        res.emplace_back(pair.first, pair.second);
+    }
+    return res;
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct DerivedCRS::Private {
+    SingleCRSNNPtr baseCRS_;
+    operation::ConversionNNPtr derivingConversion_;
+
+    Private(const SingleCRSNNPtr &baseCRSIn,
+            const operation::ConversionNNPtr &derivingConversionIn)
+        : baseCRS_(baseCRSIn), derivingConversion_(derivingConversionIn) {}
+
+    // For the conversion make a _shallowClone(), so that we can later set
+    // its targetCRS to this.
+    Private(const Private &other)
+        : baseCRS_(other.baseCRS_),
+          derivingConversion_(other.derivingConversion_->shallowClone()) {}
+};
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+// DerivedCRS is an abstract class, that virtually inherits from SingleCRS
+// Consequently the base constructor in SingleCRS will never be called by
+// that constructor. clang -Wabstract-vbase-init and VC++ underline this, but
+// other
+// compilers will complain if we don't call the base constructor.
+
+DerivedCRS::DerivedCRS(const SingleCRSNNPtr &baseCRSIn,
+                       const operation::ConversionNNPtr &derivingConversionIn,
+                       const cs::CoordinateSystemNNPtr &
+#if !defined(COMPILER_WARNS_ABOUT_ABSTRACT_VBASE_INIT)
+                           cs
+#endif
+                       )
+    :
+#if !defined(COMPILER_WARNS_ABOUT_ABSTRACT_VBASE_INIT)
+      SingleCRS(baseCRSIn->datum(), baseCRSIn->datumEnsemble(), cs),
+#endif
+      d(internal::make_unique<Private>(baseCRSIn, derivingConversionIn)) {
+}
+
+// ---------------------------------------------------------------------------
+
+DerivedCRS::DerivedCRS(const DerivedCRS &other)
+    :
+#if !defined(COMPILER_WARNS_ABOUT_ABSTRACT_VBASE_INIT)
+      SingleCRS(other),
+#endif
+      d(internal::make_unique<Private>(*other.d)) {
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+DerivedCRS::~DerivedCRS() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the base CRS of a DerivedCRS.
+ *
+ * @return the base CRS.
+ */
+const SingleCRSNNPtr &DerivedCRS::baseCRS() PROJ_CONST_DEFN {
+    return d->baseCRS_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the deriving conversion from the base CRS to this CRS.
+ *
+ * @return the deriving conversion.
+ */
+const operation::ConversionNNPtr DerivedCRS::derivingConversion() const {
+    return d->derivingConversion_->shallowClone();
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+const operation::ConversionNNPtr &
+DerivedCRS::derivingConversionRef() PROJ_CONST_DEFN {
+    return d->derivingConversion_;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+bool DerivedCRS::_isEquivalentTo(const util::IComparable *other,
+                                 util::IComparable::Criterion criterion) const {
+    auto otherDerivedCRS = dynamic_cast<const DerivedCRS *>(other);
+    const auto standardCriterion = getStandardCriterion(criterion);
+    if (otherDerivedCRS == nullptr ||
+        !SingleCRS::baseIsEquivalentTo(other, standardCriterion)) {
+        return false;
+    }
+    return d->baseCRS_->_isEquivalentTo(otherDerivedCRS->d->baseCRS_.get(),
+                                        criterion) &&
+           d->derivingConversion_->_isEquivalentTo(
+               otherDerivedCRS->d->derivingConversion_.get(),
+               standardCriterion);
+}
+
+// ---------------------------------------------------------------------------
+
+void DerivedCRS::setDerivingConversionCRS() {
+    derivingConversionRef()->setWeakSourceTargetCRS(
+        baseCRS().as_nullable(),
+        std::static_pointer_cast<CRS>(shared_from_this().as_nullable()));
+}
+
+// ---------------------------------------------------------------------------
+
+void DerivedCRS::baseExportToPROJString(
+    io::PROJStringFormatter *formatter) const // throw(io::FormattingException)
+{
+    d->derivingConversion_->_exportToPROJString(formatter);
+}
+
+// ---------------------------------------------------------------------------
+
+void DerivedCRS::baseExportToWKT(io::WKTFormatter *&formatter,
+                                 const std::string &keyword,
+                                 const std::string &baseKeyword) const {
+    formatter->startNode(keyword, !identifiers().empty());
+    formatter->addQuotedString(nameStr());
+
+    const auto &l_baseCRS = d->baseCRS_;
+    formatter->startNode(baseKeyword, !l_baseCRS->identifiers().empty());
+    formatter->addQuotedString(l_baseCRS->nameStr());
+    l_baseCRS->exportDatumOrDatumEnsembleToWkt(formatter);
+    formatter->endNode();
+
+    formatter->setUseDerivingConversion(true);
+    derivingConversionRef()->_exportToWKT(formatter);
+    formatter->setUseDerivingConversion(false);
+
+    coordinateSystem()->_exportToWKT(formatter);
+    ObjectUsage::baseExportToWKT(formatter);
+    formatter->endNode();
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct ProjectedCRS::Private {
+    GeodeticCRSNNPtr baseCRS_;
+    cs::CartesianCSNNPtr cs_;
+    Private(const GeodeticCRSNNPtr &baseCRSIn, const cs::CartesianCSNNPtr &csIn)
+        : baseCRS_(baseCRSIn), cs_(csIn) {}
+
+    inline const GeodeticCRSNNPtr &baseCRS() const { return baseCRS_; }
+
+    inline const cs::CartesianCSNNPtr &coordinateSystem() const { return cs_; }
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+ProjectedCRS::ProjectedCRS(
+    const GeodeticCRSNNPtr &baseCRSIn,
+    const operation::ConversionNNPtr &derivingConversionIn,
+    const cs::CartesianCSNNPtr &csIn)
+    : SingleCRS(baseCRSIn->datum(), baseCRSIn->datumEnsemble(), csIn),
+      DerivedCRS(baseCRSIn, derivingConversionIn, csIn),
+      d(internal::make_unique<Private>(baseCRSIn, csIn)) {}
+
+// ---------------------------------------------------------------------------
+
+ProjectedCRS::ProjectedCRS(const ProjectedCRS &other)
+    : SingleCRS(other), DerivedCRS(other),
+      d(internal::make_unique<Private>(other.baseCRS(),
+                                       other.coordinateSystem())) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+ProjectedCRS::~ProjectedCRS() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+CRSNNPtr ProjectedCRS::_shallowClone() const {
+    auto crs(ProjectedCRS::nn_make_shared<ProjectedCRS>(*this));
+    crs->assignSelf(crs);
+    crs->setDerivingConversionCRS();
+    return crs;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the base CRS (a GeodeticCRS, which is generally a
+ * GeographicCRS) of the ProjectedCRS.
+ *
+ * @return the base CRS.
+ */
+const GeodeticCRSNNPtr &ProjectedCRS::baseCRS() PROJ_CONST_DEFN {
+    return d->baseCRS();
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the cs::CartesianCS associated with the CRS.
+ *
+ * @return a CartesianCS
+ */
+const cs::CartesianCSNNPtr &ProjectedCRS::coordinateSystem() PROJ_CONST_DEFN {
+    return d->coordinateSystem();
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void ProjectedCRS::_exportToWKT(io::WKTFormatter *formatter) const {
+    const bool isWKT2 = formatter->version() == io::WKTFormatter::Version::WKT2;
+
+    const auto &l_identifiers = identifiers();
+    // Try to perfectly round-trip ESRI projectedCRS if the current object
+    // perfectly matches the database definition
+    const auto &dbContext = formatter->databaseContext();
+
+    auto l_name = nameStr();
+    std::string l_alias;
+    if (formatter->useESRIDialect() && dbContext) {
+        l_alias = dbContext->getAliasFromOfficialName(l_name, "projected_crs",
+                                                      "ESRI");
+    }
+
+    if (!isWKT2 && formatter->useESRIDialect() && !l_identifiers.empty() &&
+        *(l_identifiers[0]->codeSpace()) == "ESRI" && dbContext) {
+        try {
+            const auto definition = dbContext->getTextDefinition(
+                "projected_crs", "ESRI", l_identifiers[0]->code());
+            if (starts_with(definition, "PROJCS")) {
+                auto crsFromFromDef = io::WKTParser()
+                                          .attachDatabaseContext(dbContext)
+                                          .createFromWKT(definition);
+                if (_isEquivalentTo(
+                        dynamic_cast<IComparable *>(crsFromFromDef.get()),
+                        util::IComparable::Criterion::EQUIVALENT)) {
+                    formatter->ingestWKTNode(
+                        io::WKTNode::createFrom(definition));
+                    return;
+                }
+            }
+        } catch (const std::exception &) {
+        }
+    } else if (!isWKT2 && formatter->useESRIDialect() && !l_alias.empty()) {
+        try {
+            auto res =
+                io::AuthorityFactory::create(NN_NO_CHECK(dbContext), "ESRI")
+                    ->createObjectsFromName(
+                        l_alias,
+                        {io::AuthorityFactory::ObjectType::PROJECTED_CRS},
+                        false);
+            if (res.size() == 1) {
+                const auto definition = dbContext->getTextDefinition(
+                    "projected_crs", "ESRI",
+                    res.front()->identifiers()[0]->code());
+                if (starts_with(definition, "PROJCS")) {
+                    if (_isEquivalentTo(
+                            dynamic_cast<IComparable *>(res.front().get()),
+                            util::IComparable::Criterion::EQUIVALENT)) {
+                        formatter->ingestWKTNode(
+                            io::WKTNode::createFrom(definition));
+                        return;
+                    }
+                }
+            }
+        } catch (const std::exception &) {
+        }
+    }
+
+    const auto &l_coordinateSystem = d->coordinateSystem();
+    const auto &axisList = l_coordinateSystem->axisList();
+    if (axisList.size() == 3 && !(isWKT2 && formatter->use2018Keywords())) {
+        io::FormattingException::Throw(
+            "Projected 3D CRS can only be exported since WKT2:2018");
+    }
+
+    const auto exportAxis = [&l_coordinateSystem, &axisList, &formatter]() {
+        const auto oldAxisOutputRule = formatter->outputAxis();
+        if (oldAxisOutputRule ==
+            io::WKTFormatter::OutputAxisRule::WKT1_GDAL_EPSG_STYLE) {
+            if (&axisList[0]->direction() == &cs::AxisDirection::EAST &&
+                &axisList[1]->direction() == &cs::AxisDirection::NORTH) {
+                formatter->setOutputAxis(io::WKTFormatter::OutputAxisRule::YES);
+            }
+        }
+        l_coordinateSystem->_exportToWKT(formatter);
+        formatter->setOutputAxis(oldAxisOutputRule);
+    };
+
+    if (!isWKT2 && !formatter->useESRIDialect() &&
+        starts_with(nameStr(), "Popular Visualisation CRS / Mercator")) {
+        formatter->startNode(io::WKTConstants::PROJCS, !l_identifiers.empty());
+        formatter->addQuotedString(nameStr());
+        formatter->setTOWGS84Parameters({0, 0, 0, 0, 0, 0, 0});
+        baseCRS()->_exportToWKT(formatter);
+        formatter->setTOWGS84Parameters({});
+
+        formatter->startNode(io::WKTConstants::PROJECTION, false);
+        formatter->addQuotedString("Mercator_1SP");
+        formatter->endNode();
+
+        formatter->startNode(io::WKTConstants::PARAMETER, false);
+        formatter->addQuotedString("central_meridian");
+        formatter->add(0.0);
+        formatter->endNode();
+
+        formatter->startNode(io::WKTConstants::PARAMETER, false);
+        formatter->addQuotedString("scale_factor");
+        formatter->add(1.0);
+        formatter->endNode();
+
+        formatter->startNode(io::WKTConstants::PARAMETER, false);
+        formatter->addQuotedString("false_easting");
+        formatter->add(0.0);
+        formatter->endNode();
+
+        formatter->startNode(io::WKTConstants::PARAMETER, false);
+        formatter->addQuotedString("false_northing");
+        formatter->add(0.0);
+        formatter->endNode();
+
+        axisList[0]->unit()._exportToWKT(formatter);
+        exportAxis();
+        derivingConversionRef()->addWKTExtensionNode(formatter);
+        ObjectUsage::baseExportToWKT(formatter);
+        formatter->endNode();
+        return;
+    }
+
+    formatter->startNode(isWKT2 ? io::WKTConstants::PROJCRS
+                                : io::WKTConstants::PROJCS,
+                         !l_identifiers.empty());
+
+    if (formatter->useESRIDialect()) {
+        if (l_alias.empty()) {
+            l_name = io::WKTFormatter::morphNameToESRI(l_name);
+        } else {
+            l_name = l_alias;
+        }
+    }
+    if (!isWKT2 && !formatter->useESRIDialect() && isDeprecated()) {
+        l_name += " (deprecated)";
+    }
+    formatter->addQuotedString(l_name);
+
+    const auto &l_baseCRS = d->baseCRS();
+    const auto &geodeticCRSAxisList = l_baseCRS->coordinateSystem()->axisList();
+
+    if (isWKT2) {
+        formatter->startNode(
+            (formatter->use2018Keywords() &&
+             dynamic_cast<const GeographicCRS *>(l_baseCRS.get()))
+                ? io::WKTConstants::BASEGEOGCRS
+                : io::WKTConstants::BASEGEODCRS,
+            !l_baseCRS->identifiers().empty());
+        formatter->addQuotedString(l_baseCRS->nameStr());
+        l_baseCRS->exportDatumOrDatumEnsembleToWkt(formatter);
+        // insert ellipsoidal cs unit when the units of the map
+        // projection angular parameters are not explicitly given within those
+        // parameters. See
+        // http://docs.opengeospatial.org/is/12-063r5/12-063r5.html#61
+        if (formatter->primeMeridianOrParameterUnitOmittedIfSameAsAxis()) {
+            geodeticCRSAxisList[0]->unit()._exportToWKT(formatter);
+        }
+        l_baseCRS->primeMeridian()->_exportToWKT(formatter);
+        formatter->endNode();
+    } else {
+        const auto oldAxisOutputRule = formatter->outputAxis();
+        formatter->setOutputAxis(io::WKTFormatter::OutputAxisRule::NO);
+        l_baseCRS->_exportToWKT(formatter);
+        formatter->setOutputAxis(oldAxisOutputRule);
+    }
+
+    formatter->pushAxisLinearUnit(
+        common::UnitOfMeasure::create(axisList[0]->unit()));
+
+    formatter->pushAxisAngularUnit(
+        common::UnitOfMeasure::create(geodeticCRSAxisList[0]->unit()));
+
+    derivingConversionRef()->_exportToWKT(formatter);
+
+    formatter->popAxisAngularUnit();
+
+    formatter->popAxisLinearUnit();
+
+    if (!isWKT2) {
+        axisList[0]->unit()._exportToWKT(formatter);
+    }
+
+    exportAxis();
+
+    if (!isWKT2 && !formatter->useESRIDialect()) {
+        const auto &extensionProj4 = CRS::getPrivate()->extensionProj4_;
+        if (!extensionProj4.empty()) {
+            formatter->startNode(io::WKTConstants::EXTENSION, false);
+            formatter->addQuotedString("PROJ4");
+            formatter->addQuotedString(extensionProj4);
+            formatter->endNode();
+        } else {
+            derivingConversionRef()->addWKTExtensionNode(formatter);
+        }
+    }
+
+    ObjectUsage::baseExportToWKT(formatter);
+    formatter->endNode();
+    return;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+void ProjectedCRS::_exportToPROJString(
+    io::PROJStringFormatter *formatter) const // throw(io::FormattingException)
+{
+    if (formatter->convention() ==
+        io::PROJStringFormatter::Convention::PROJ_4) {
+        const auto &extensionProj4 = CRS::getPrivate()->extensionProj4_;
+        if (!extensionProj4.empty()) {
+            formatter->ingestPROJString(extensionProj4);
+            formatter->addNoDefs(false);
+            return;
+        }
+    }
+
+    baseExportToPROJString(formatter);
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ProjectedCRS from a base CRS, a deriving
+ * operation::Conversion
+ * and a coordinate system.
+ *
+ * @param properties See \ref general_properties.
+ * At minimum the name should be defined.
+ * @param baseCRSIn The base CRS, a GeodeticCRS that is generally a
+ * GeographicCRS.
+ * @param derivingConversionIn The deriving operation::Conversion (typically
+ * using a map
+ * projection method)
+ * @param csIn The coordniate system.
+ * @return new ProjectedCRS.
+ */
+ProjectedCRSNNPtr
+ProjectedCRS::create(const util::PropertyMap &properties,
+                     const GeodeticCRSNNPtr &baseCRSIn,
+                     const operation::ConversionNNPtr &derivingConversionIn,
+                     const cs::CartesianCSNNPtr &csIn) {
+    auto crs = ProjectedCRS::nn_make_shared<ProjectedCRS>(
+        baseCRSIn, derivingConversionIn, csIn);
+    crs->assignSelf(crs);
+    crs->setProperties(properties);
+    crs->setDerivingConversionCRS();
+    properties.getStringValue("EXTENSION_PROJ4",
+                              crs->CRS::getPrivate()->extensionProj4_);
+    crs->CRS::getPrivate()->setImplicitCS(properties);
+    return crs;
+}
+
+// ---------------------------------------------------------------------------
+
+bool ProjectedCRS::_isEquivalentTo(
+    const util::IComparable *other,
+    util::IComparable::Criterion criterion) const {
+    auto otherProjCRS = dynamic_cast<const ProjectedCRS *>(other);
+    return otherProjCRS != nullptr &&
+           DerivedCRS::_isEquivalentTo(other, criterion);
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+ProjectedCRSNNPtr
+ProjectedCRS::alterParametersLinearUnit(const common::UnitOfMeasure &unit,
+                                        bool convertToNewUnit) const {
+    return create(createPropertyMap(this), baseCRS(),
+                  derivingConversionRef()->alterParametersLinearUnit(
+                      unit, convertToNewUnit),
+                  coordinateSystem());
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void ProjectedCRS::addUnitConvertAndAxisSwap(io::PROJStringFormatter *formatter,
+                                             bool axisSpecFound) const {
+    const auto &axisList = d->coordinateSystem()->axisList();
+    const auto &unit = axisList[0]->unit();
+    if (!unit._isEquivalentTo(common::UnitOfMeasure::METRE,
+                              util::IComparable::Criterion::EQUIVALENT)) {
+        auto projUnit = unit.exportToPROJString();
+        const double toSI = unit.conversionToSI();
+        if (formatter->convention() ==
+            io::PROJStringFormatter::Convention::PROJ_5) {
+            formatter->addStep("unitconvert");
+            formatter->addParam("xy_in", "m");
+            formatter->addParam("z_in", "m");
+            if (projUnit.empty()) {
+                formatter->addParam("xy_out", toSI);
+                formatter->addParam("z_out", toSI);
+            } else {
+                formatter->addParam("xy_out", projUnit);
+                formatter->addParam("z_out", projUnit);
+            }
+        } else {
+            if (projUnit.empty()) {
+                formatter->addParam("to_meter", toSI);
+            } else {
+                formatter->addParam("units", projUnit);
+            }
+        }
+    } else if (formatter->convention() ==
+               io::PROJStringFormatter::Convention::PROJ_4) {
+        // could come from the hardcoded def of webmerc
+        if (!formatter->hasParam("units")) {
+            formatter->addParam("units", "m");
+        }
+    }
+
+    if (formatter->convention() ==
+            io::PROJStringFormatter::Convention::PROJ_5 &&
+        !axisSpecFound) {
+        const auto &dir0 = axisList[0]->direction();
+        const auto &dir1 = axisList[1]->direction();
+        if (!(&dir0 == &cs::AxisDirection::EAST &&
+              &dir1 == &cs::AxisDirection::NORTH) &&
+            // For polar projections, that have south+south direction,
+            // we don't want to mess with axes.
+            dir0 != dir1) {
+
+            const char *order[2] = {nullptr, nullptr};
+            for (int i = 0; i < 2; i++) {
+                const auto &dir = axisList[i]->direction();
+                if (&dir == &cs::AxisDirection::WEST)
+                    order[i] = "-1";
+                else if (&dir == &cs::AxisDirection::EAST)
+                    order[i] = "1";
+                else if (&dir == &cs::AxisDirection::SOUTH)
+                    order[i] = "-2";
+                else if (&dir == &cs::AxisDirection::NORTH)
+                    order[i] = "2";
+            }
+
+            if (order[0] && order[1]) {
+                formatter->addStep("axisswap");
+                char orderStr[10];
+                strcpy(orderStr, order[0]);
+                strcat(orderStr, ",");
+                strcat(orderStr, order[1]);
+                formatter->addParam("order", orderStr);
+            }
+        } else {
+            const auto &name0 = axisList[0]->nameStr();
+            const auto &name1 = axisList[1]->nameStr();
+            const bool northingEasting = ci_starts_with(name0, "northing") &&
+                                         ci_starts_with(name1, "easting");
+            // case of EPSG:32661 ["WGS 84 / UPS North (N,E)]"
+            // case of EPSG:32761 ["WGS 84 / UPS South (N,E)]"
+            if (((&dir0 == &cs::AxisDirection::SOUTH &&
+                  &dir1 == &cs::AxisDirection::SOUTH) ||
+                 (&dir0 == &cs::AxisDirection::NORTH &&
+                  &dir1 == &cs::AxisDirection::NORTH)) &&
+                northingEasting) {
+                formatter->addStep("axisswap");
+                formatter->addParam("order", "2,1");
+            }
+        }
+    }
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Identify the CRS with reference CRSs.
+ *
+ * The candidate CRSs are either hard-coded, or looked in the database when
+ * authorityFactory is not null.
+ *
+ * The method returns a list of matching reference CRS, and the percentage
+ * (0-100) of confidence in the match. The list is sorted by decreasing
+ * confidence.
+ *
+ * 100% means that the name of the reference entry
+ * perfectly matches the CRS name, and both are equivalent. In which case a
+ * single result is returned.
+ * 90% means that CRS are equivalent, but the names are not exactly the same.
+ * 70% means that CRS are equivalent (equivalent base CRS, conversion and
+ * coordinate system), but the names do not match at all.
+ * 50% means that CRS have similarity (equivalent base CRS and conversion),
+ * but the coordinate system do not match (e.g. different axis ordering or
+ * axis unit).
+ * 25% means that the CRS are not equivalent, but there is some similarity in
+ * the names.
+ *
+ * For the purpose of this function, equivalence is tested with the
+ * util::IComparable::Criterion::EQUIVALENT_EXCEPT_AXIS_ORDER_GEOGCRS, that is
+ * to say that the axis order of the base GeographicCRS is ignored.
+ *
+ * @param authorityFactory Authority factory (or null, but degraded
+ * functionality)
+ * @return a list of matching reference CRS, and the percentage (0-100) of
+ * confidence in the match.
+ */
+std::list<std::pair<ProjectedCRSNNPtr, int>>
+ProjectedCRS::identify(const io::AuthorityFactoryPtr &authorityFactory) const {
+    typedef std::pair<ProjectedCRSNNPtr, int> Pair;
+    std::list<Pair> res;
+
+    const auto &thisName(nameStr());
+
+    std::list<std::pair<GeodeticCRSNNPtr, int>> baseRes;
+    const auto &l_baseCRS(baseCRS());
+    auto geogCRS = dynamic_cast<const GeographicCRS *>(l_baseCRS.get());
+    if (geogCRS &&
+        geogCRS->coordinateSystem()->axisOrder() ==
+            cs::EllipsoidalCS::AxisOrder::LONG_EAST_LAT_NORTH) {
+        baseRes =
+            GeographicCRS::create(
+                util::PropertyMap().set(common::IdentifiedObject::NAME_KEY,
+                                        geogCRS->nameStr()),
+                geogCRS->datum(), geogCRS->datumEnsemble(),
+                cs::EllipsoidalCS::createLatitudeLongitude(
+                    geogCRS->coordinateSystem()->axisList()[0]->unit()))
+                ->identify(authorityFactory);
+    } else {
+        baseRes = l_baseCRS->identify(authorityFactory);
+    }
+
+    int zone = 0;
+    bool north = false;
+
+    auto computeConfidence = [&thisName](const std::string &crsName) {
+        return crsName == thisName ? 100
+                                   : metadata::Identifier::isEquivalentName(
+                                         crsName.c_str(), thisName.c_str())
+                                         ? 90
+                                         : 70;
+    };
+    auto computeUTMCRSName = [](const char *base, int l_zone, bool l_north) {
+        return base + toString(l_zone) + (l_north ? "N" : "S");
+    };
+
+    const auto &conv = derivingConversionRef();
+    const auto &cs = coordinateSystem();
+    if (baseRes.size() == 1 && baseRes.front().second >= 70 &&
+        conv->isUTM(zone, north) &&
+        cs->_isEquivalentTo(
+            cs::CartesianCS::createEastingNorthing(common::UnitOfMeasure::METRE)
+                .get())) {
+        if (baseRes.front().first->_isEquivalentTo(
+                GeographicCRS::EPSG_4326.get(),
+                util::IComparable::Criterion::EQUIVALENT)) {
+            std::string crsName(
+                computeUTMCRSName("WGS 84 / UTM zone ", zone, north));
+            res.emplace_back(
+                ProjectedCRS::create(
+                    createMapNameEPSGCode(crsName.c_str(),
+                                          (north ? 32600 : 32700) + zone),
+                    GeographicCRS::EPSG_4326, conv->identify(), cs),
+                computeConfidence(crsName));
+            return res;
+        } else if (((zone >= 1 && zone <= 22) || zone == 59 || zone == 60) &&
+                   north &&
+                   baseRes.front().first->_isEquivalentTo(
+                       GeographicCRS::EPSG_4267.get(),
+                       util::IComparable::Criterion::EQUIVALENT)) {
+            std::string crsName(
+                computeUTMCRSName("NAD27 / UTM zone ", zone, north));
+            res.emplace_back(
+                ProjectedCRS::create(
+                    createMapNameEPSGCode(crsName.c_str(),
+                                          (zone >= 59) ? 3370 + zone - 59
+                                                       : 26700 + zone),
+                    GeographicCRS::EPSG_4267, conv->identify(), cs),
+                computeConfidence(crsName));
+            return res;
+        } else if (((zone >= 1 && zone <= 23) || zone == 59 || zone == 60) &&
+                   north &&
+                   baseRes.front().first->_isEquivalentTo(
+                       GeographicCRS::EPSG_4269.get(),
+                       util::IComparable::Criterion::EQUIVALENT)) {
+            std::string crsName(
+                computeUTMCRSName("NAD83 / UTM zone ", zone, north));
+            res.emplace_back(
+                ProjectedCRS::create(
+                    createMapNameEPSGCode(crsName.c_str(),
+                                          (zone >= 59) ? 3372 + zone - 59
+                                                       : 26900 + zone),
+                    GeographicCRS::EPSG_4269, conv->identify(), cs),
+                computeConfidence(crsName));
+            return res;
+        }
+    }
+
+    if (authorityFactory) {
+
+        const bool unsignificantName = thisName.empty() ||
+                                       ci_equal(thisName, "unknown") ||
+                                       ci_equal(thisName, "unnamed");
+        bool foundEquivalentName = false;
+
+        if (!identifiers().empty()) {
+            // If the CRS has already an id, check in the database for the
+            // official object, and verify that they are equivalent.
+            for (const auto &id : identifiers()) {
+                try {
+                    auto crs = io::AuthorityFactory::create(
+                                   authorityFactory->databaseContext(),
+                                   *id->codeSpace())
+                                   ->createProjectedCRS(id->code());
+                    bool match = _isEquivalentTo(
+                        crs.get(), util::IComparable::Criterion::
+                                       EQUIVALENT_EXCEPT_AXIS_ORDER_GEOGCRS);
+                    res.emplace_back(crs, match ? 100 : 25);
+                    return res;
+                } catch (const std::exception &) {
+                }
+            }
+        } else if (!unsignificantName) {
+            for (int ipass = 0; ipass < 2; ipass++) {
+                const bool approximateMatch = ipass == 1;
+                auto objects = authorityFactory->createObjectsFromName(
+                    thisName, {io::AuthorityFactory::ObjectType::PROJECTED_CRS},
+                    approximateMatch);
+                for (const auto &obj : objects) {
+                    auto crs = util::nn_dynamic_pointer_cast<ProjectedCRS>(obj);
+                    assert(crs);
+                    auto crsNN = NN_NO_CHECK(crs);
+                    const bool eqName = metadata::Identifier::isEquivalentName(
+                        thisName.c_str(), crs->nameStr().c_str());
+                    foundEquivalentName |= eqName;
+                    if (_isEquivalentTo(
+                            crs.get(),
+                            util::IComparable::Criterion::
+                                EQUIVALENT_EXCEPT_AXIS_ORDER_GEOGCRS)) {
+                        if (crs->nameStr() == thisName) {
+                            res.clear();
+                            res.emplace_back(crsNN, 100);
+                            return res;
+                        }
+                        res.emplace_back(crsNN, eqName ? 90 : 70);
+                    } else if (crs->nameStr() == thisName &&
+                               CRS::getPrivate()->implicitCS_ &&
+                               l_baseCRS->_isEquivalentTo(
+                                   crs->baseCRS().get(),
+                                   util::IComparable::Criterion::
+                                       EQUIVALENT_EXCEPT_AXIS_ORDER_GEOGCRS) &&
+                               derivingConversionRef()->_isEquivalentTo(
+                                   crs->derivingConversionRef().get(),
+                                   util::IComparable::Criterion::EQUIVALENT) &&
+                               objects.size() == 1) {
+                        res.clear();
+                        res.emplace_back(crsNN, 100);
+                        return res;
+                    } else {
+                        res.emplace_back(crsNN, 25);
+                    }
+                }
+                if (!res.empty()) {
+                    break;
+                }
+            }
+        }
+
+        const auto lambdaSort = [&thisName](const Pair &a, const Pair &b) {
+            // First consider confidence
+            if (a.second > b.second) {
+                return true;
+            }
+            if (a.second < b.second) {
+                return false;
+            }
+
+            // Then consider exact name matching
+            const auto &aName(a.first->nameStr());
+            const auto &bName(b.first->nameStr());
+            if (aName == thisName && bName != thisName) {
+                return true;
+            }
+            if (bName == thisName && aName != thisName) {
+                return false;
+            }
+
+            // Arbitrary final sorting criterion
+            return aName < bName;
+        };
+
+        // Sort results
+        res.sort(lambdaSort);
+
+        if (identifiers().empty() && !foundEquivalentName &&
+            (res.empty() || res.front().second < 50)) {
+            std::set<std::pair<std::string, std::string>> alreadyKnown;
+            for (const auto &pair : res) {
+                const auto &ids = pair.first->identifiers();
+                assert(!ids.empty());
+                alreadyKnown.insert(std::pair<std::string, std::string>(
+                    *(ids[0]->codeSpace()), ids[0]->code()));
+            }
+
+            auto self = NN_NO_CHECK(std::dynamic_pointer_cast<ProjectedCRS>(
+                shared_from_this().as_nullable()));
+            auto candidates =
+                authorityFactory->createProjectedCRSFromExisting(self);
+            const auto &ellipsoid = l_baseCRS->ellipsoid();
+            for (const auto &crs : candidates) {
+                const auto &ids = crs->identifiers();
+                assert(!ids.empty());
+                if (alreadyKnown.find(std::pair<std::string, std::string>(
+                        *(ids[0]->codeSpace()), ids[0]->code())) !=
+                    alreadyKnown.end()) {
+                    continue;
+                }
+
+                if (_isEquivalentTo(crs.get(),
+                                    util::IComparable::Criterion::
+                                        EQUIVALENT_EXCEPT_AXIS_ORDER_GEOGCRS)) {
+                    res.emplace_back(crs, unsignificantName ? 90 : 70);
+                } else if (ellipsoid->_isEquivalentTo(
+                               crs->baseCRS()->ellipsoid().get(),
+                               util::IComparable::Criterion::EQUIVALENT) &&
+                           derivingConversionRef()->_isEquivalentTo(
+                               crs->derivingConversionRef().get(),
+                               util::IComparable::Criterion::EQUIVALENT)) {
+                    if (coordinateSystem()->_isEquivalentTo(
+                            crs->coordinateSystem().get(),
+                            util::IComparable::Criterion::EQUIVALENT)) {
+                        res.emplace_back(crs, 70);
+                    } else {
+                        res.emplace_back(crs, 50);
+                    }
+                } else {
+                    res.emplace_back(crs, 25);
+                }
+            }
+
+            res.sort(lambdaSort);
+        }
+
+        // Keep only results of the highest confidence
+        if (res.size() >= 2) {
+            const auto highestConfidence = res.front().second;
+            std::list<Pair> newRes;
+            for (const auto &pair : res) {
+                if (pair.second == highestConfidence) {
+                    newRes.push_back(pair);
+                } else {
+                    break;
+                }
+            }
+            return newRes;
+        }
+    }
+
+    return res;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+std::list<std::pair<CRSNNPtr, int>>
+ProjectedCRS::_identify(const io::AuthorityFactoryPtr &authorityFactory) const {
+    typedef std::pair<CRSNNPtr, int> Pair;
+    std::list<Pair> res;
+    auto resTemp = identify(authorityFactory);
+    for (const auto &pair : resTemp) {
+        res.emplace_back(pair.first, pair.second);
+    }
+    return res;
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct CompoundCRS::Private {
+    std::vector<CRSNNPtr> components_{};
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+CompoundCRS::CompoundCRS(const std::vector<CRSNNPtr> &components)
+    : CRS(), d(internal::make_unique<Private>()) {
+    d->components_ = components;
+}
+
+// ---------------------------------------------------------------------------
+
+CompoundCRS::CompoundCRS(const CompoundCRS &other)
+    : CRS(other), d(internal::make_unique<Private>(*other.d)) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+CompoundCRS::~CompoundCRS() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+CRSNNPtr CompoundCRS::_shallowClone() const {
+    auto crs(CompoundCRS::nn_make_shared<CompoundCRS>(*this));
+    crs->assignSelf(crs);
+    return crs;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the components of a CompoundCRS.
+ *
+ * @return the components.
+ */
+const std::vector<CRSNNPtr> &
+CompoundCRS::componentReferenceSystems() PROJ_CONST_DEFN {
+    return d->components_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a CompoundCRS from a vector of CRS.
+ *
+ * @param properties See \ref general_properties.
+ * At minimum the name should be defined.
+ * @param components the component CRS of the CompoundCRS.
+ * @return new CompoundCRS.
+ */
+CompoundCRSNNPtr CompoundCRS::create(const util::PropertyMap &properties,
+                                     const std::vector<CRSNNPtr> &components) {
+    auto compoundCRS(CompoundCRS::nn_make_shared<CompoundCRS>(components));
+    compoundCRS->assignSelf(compoundCRS);
+    compoundCRS->setProperties(properties);
+    if (!properties.get(common::IdentifiedObject::NAME_KEY)) {
+        std::string name;
+        for (const auto &crs : components) {
+            if (!name.empty()) {
+                name += " + ";
+            }
+            const auto &l_name = crs->nameStr();
+            if (!l_name.empty()) {
+                name += l_name;
+            } else {
+                name += "unnamed";
+            }
+        }
+        util::PropertyMap propertyName;
+        propertyName.set(common::IdentifiedObject::NAME_KEY, name);
+        compoundCRS->setProperties(propertyName);
+    }
+
+    return compoundCRS;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void CompoundCRS::_exportToWKT(io::WKTFormatter *formatter) const {
+    const bool isWKT2 = formatter->version() == io::WKTFormatter::Version::WKT2;
+    formatter->startNode(isWKT2 ? io::WKTConstants::COMPOUNDCRS
+                                : io::WKTConstants::COMPD_CS,
+                         !identifiers().empty());
+    formatter->addQuotedString(nameStr());
+    for (const auto &crs : componentReferenceSystems()) {
+        crs->_exportToWKT(formatter);
+    }
+    ObjectUsage::baseExportToWKT(formatter);
+    formatter->endNode();
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+void CompoundCRS::_exportToPROJString(
+    io::PROJStringFormatter *formatter) const // throw(io::FormattingException)
+{
+    for (const auto &crs : componentReferenceSystems()) {
+        auto crs_exportable =
+            dynamic_cast<const IPROJStringExportable *>(crs.get());
+        if (crs_exportable) {
+            crs_exportable->_exportToPROJString(formatter);
+        }
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+bool CompoundCRS::_isEquivalentTo(
+    const util::IComparable *other,
+    util::IComparable::Criterion criterion) const {
+    auto otherCompoundCRS = dynamic_cast<const CompoundCRS *>(other);
+    if (otherCompoundCRS == nullptr ||
+        (criterion == util::IComparable::Criterion::STRICT &&
+         !ObjectUsage::_isEquivalentTo(other, criterion))) {
+        return false;
+    }
+    const auto &components = componentReferenceSystems();
+    const auto &otherComponents = otherCompoundCRS->componentReferenceSystems();
+    if (components.size() != otherComponents.size()) {
+        return false;
+    }
+    for (size_t i = 0; i < components.size(); i++) {
+        if (!components[i]->_isEquivalentTo(otherComponents[i].get(),
+                                            criterion)) {
+            return false;
+        }
+    }
+    return true;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Identify the CRS with reference CRSs.
+ *
+ * The candidate CRSs are looked in the database when
+ * authorityFactory is not null.
+ *
+ * The method returns a list of matching reference CRS, and the percentage
+ * (0-100) of confidence in the match. The list is sorted by decreasing
+ * confidence.
+ *
+ * 100% means that the name of the reference entry
+ * perfectly matches the CRS name, and both are equivalent. In which case a
+ * single result is returned.
+ * 90% means that CRS are equivalent, but the names are not exactly the same.
+ * 70% means that CRS are equivalent (equivalent horizontal and vertical CRS),
+ * but the names do not match at all.
+ * 25% means that the CRS are not equivalent, but there is some similarity in
+ * the names.
+ *
+ * @param authorityFactory Authority factory (if null, will return an empty
+ * list)
+ * @return a list of matching reference CRS, and the percentage (0-100) of
+ * confidence in the match.
+ */
+std::list<std::pair<CompoundCRSNNPtr, int>>
+CompoundCRS::identify(const io::AuthorityFactoryPtr &authorityFactory) const {
+    typedef std::pair<CompoundCRSNNPtr, int> Pair;
+    std::list<Pair> res;
+
+    const auto &thisName(nameStr());
+
+    if (authorityFactory) {
+
+        const bool unsignificantName = thisName.empty() ||
+                                       ci_equal(thisName, "unknown") ||
+                                       ci_equal(thisName, "unnamed");
+        bool foundEquivalentName = false;
+
+        if (!identifiers().empty()) {
+            // If the CRS has already an id, check in the database for the
+            // official object, and verify that they are equivalent.
+            for (const auto &id : identifiers()) {
+                try {
+                    auto crs = io::AuthorityFactory::create(
+                                   authorityFactory->databaseContext(),
+                                   *id->codeSpace())
+                                   ->createCompoundCRS(id->code());
+                    bool match = _isEquivalentTo(
+                        crs.get(), util::IComparable::Criterion::EQUIVALENT);
+                    res.emplace_back(crs, match ? 100 : 25);
+                    return res;
+                } catch (const std::exception &) {
+                }
+            }
+        } else if (!unsignificantName) {
+            for (int ipass = 0; ipass < 2; ipass++) {
+                const bool approximateMatch = ipass == 1;
+                auto objects = authorityFactory->createObjectsFromName(
+                    thisName, {io::AuthorityFactory::ObjectType::COMPOUND_CRS},
+                    approximateMatch);
+                for (const auto &obj : objects) {
+                    auto crs = util::nn_dynamic_pointer_cast<CompoundCRS>(obj);
+                    assert(crs);
+                    auto crsNN = NN_NO_CHECK(crs);
+                    const bool eqName = metadata::Identifier::isEquivalentName(
+                        thisName.c_str(), crs->nameStr().c_str());
+                    foundEquivalentName |= eqName;
+                    if (_isEquivalentTo(
+                            crs.get(),
+                            util::IComparable::Criterion::EQUIVALENT)) {
+                        if (crs->nameStr() == thisName) {
+                            res.clear();
+                            res.emplace_back(crsNN, 100);
+                            return res;
+                        }
+                        res.emplace_back(crsNN, eqName ? 90 : 70);
+                    } else {
+                        res.emplace_back(crsNN, 25);
+                    }
+                }
+                if (!res.empty()) {
+                    break;
+                }
+            }
+        }
+
+        const auto lambdaSort = [&thisName](const Pair &a, const Pair &b) {
+            // First consider confidence
+            if (a.second > b.second) {
+                return true;
+            }
+            if (a.second < b.second) {
+                return false;
+            }
+
+            // Then consider exact name matching
+            const auto &aName(a.first->nameStr());
+            const auto &bName(b.first->nameStr());
+            if (aName == thisName && bName != thisName) {
+                return true;
+            }
+            if (bName == thisName && aName != thisName) {
+                return false;
+            }
+
+            // Arbitrary final sorting criterion
+            return aName < bName;
+        };
+
+        // Sort results
+        res.sort(lambdaSort);
+
+        if (identifiers().empty() && !foundEquivalentName &&
+            (res.empty() || res.front().second < 50)) {
+            std::set<std::pair<std::string, std::string>> alreadyKnown;
+            for (const auto &pair : res) {
+                const auto &ids = pair.first->identifiers();
+                assert(!ids.empty());
+                alreadyKnown.insert(std::pair<std::string, std::string>(
+                    *(ids[0]->codeSpace()), ids[0]->code()));
+            }
+
+            auto self = NN_NO_CHECK(std::dynamic_pointer_cast<CompoundCRS>(
+                shared_from_this().as_nullable()));
+            auto candidates =
+                authorityFactory->createCompoundCRSFromExisting(self);
+            for (const auto &crs : candidates) {
+                const auto &ids = crs->identifiers();
+                assert(!ids.empty());
+                if (alreadyKnown.find(std::pair<std::string, std::string>(
+                        *(ids[0]->codeSpace()), ids[0]->code())) !=
+                    alreadyKnown.end()) {
+                    continue;
+                }
+
+                if (_isEquivalentTo(crs.get(),
+                                    util::IComparable::Criterion::EQUIVALENT)) {
+                    res.emplace_back(crs, unsignificantName ? 90 : 70);
+                } else {
+                    res.emplace_back(crs, 25);
+                }
+            }
+
+            res.sort(lambdaSort);
+        }
+
+        // Keep only results of the highest confidence
+        if (res.size() >= 2) {
+            const auto highestConfidence = res.front().second;
+            std::list<Pair> newRes;
+            for (const auto &pair : res) {
+                if (pair.second == highestConfidence) {
+                    newRes.push_back(pair);
+                } else {
+                    break;
+                }
+            }
+            return newRes;
+        }
+    }
+
+    return res;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+std::list<std::pair<CRSNNPtr, int>>
+CompoundCRS::_identify(const io::AuthorityFactoryPtr &authorityFactory) const {
+    typedef std::pair<CRSNNPtr, int> Pair;
+    std::list<Pair> res;
+    auto resTemp = identify(authorityFactory);
+    for (const auto &pair : resTemp) {
+        res.emplace_back(pair.first, pair.second);
+    }
+    return res;
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct PROJ_INTERNAL BoundCRS::Private {
+    CRSNNPtr baseCRS_;
+    CRSNNPtr hubCRS_;
+    operation::TransformationNNPtr transformation_;
+
+    Private(const CRSNNPtr &baseCRSIn, const CRSNNPtr &hubCRSIn,
+            const operation::TransformationNNPtr &transformationIn);
+
+    inline const CRSNNPtr &baseCRS() const { return baseCRS_; }
+    inline const CRSNNPtr &hubCRS() const { return hubCRS_; }
+    inline const operation::TransformationNNPtr &transformation() const {
+        return transformation_;
+    }
+};
+
+BoundCRS::Private::Private(
+    const CRSNNPtr &baseCRSIn, const CRSNNPtr &hubCRSIn,
+    const operation::TransformationNNPtr &transformationIn)
+    : baseCRS_(baseCRSIn), hubCRS_(hubCRSIn),
+      transformation_(transformationIn) {}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+BoundCRS::BoundCRS(const CRSNNPtr &baseCRSIn, const CRSNNPtr &hubCRSIn,
+                   const operation::TransformationNNPtr &transformationIn)
+    : d(internal::make_unique<Private>(baseCRSIn, hubCRSIn, transformationIn)) {
+}
+
+// ---------------------------------------------------------------------------
+
+BoundCRS::BoundCRS(const BoundCRS &other)
+    : CRS(other),
+      d(internal::make_unique<Private>(other.d->baseCRS(), other.d->hubCRS(),
+                                       other.d->transformation())) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+BoundCRS::~BoundCRS() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+BoundCRSNNPtr BoundCRS::shallowCloneAsBoundCRS() const {
+    auto crs(BoundCRS::nn_make_shared<BoundCRS>(*this));
+    crs->assignSelf(crs);
+    return crs;
+}
+
+// ---------------------------------------------------------------------------
+
+CRSNNPtr BoundCRS::_shallowClone() const { return shallowCloneAsBoundCRS(); }
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the base CRS.
+ *
+ * This is the CRS into which coordinates of the BoundCRS are expressed.
+ *
+ * @return the base CRS.
+ */
+const CRSNNPtr &BoundCRS::baseCRS() PROJ_CONST_DEFN { return d->baseCRS_; }
+
+// ---------------------------------------------------------------------------
+
+// The only legit caller is BoundCRS::baseCRSWithCanonicalBoundCRS()
+void CRS::setCanonicalBoundCRS(const BoundCRSNNPtr &boundCRS) {
+
+    d->canonicalBoundCRS_ = boundCRS;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return a shallow clone of the base CRS that points to a
+ * shallow clone of this BoundCRS.
+ *
+ * The base CRS is the CRS into which coordinates of the BoundCRS are expressed.
+ *
+ * The returned CRS will actually be a shallow clone of the actual base CRS,
+ * with the extra property that CRS::canonicalBoundCRS() will point to a
+ * shallow clone of this BoundCRS. Use this only if you want to work with
+ * the base CRS object rather than the BoundCRS, but wanting to be able to
+ * retrieve the BoundCRS later.
+ *
+ * @return the base CRS.
+ */
+CRSNNPtr BoundCRS::baseCRSWithCanonicalBoundCRS() const {
+    auto baseCRSClone = baseCRS()->_shallowClone();
+    baseCRSClone->setCanonicalBoundCRS(shallowCloneAsBoundCRS());
+    return baseCRSClone;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the target / hub CRS.
+ *
+ * @return the hub CRS.
+ */
+const CRSNNPtr &BoundCRS::hubCRS() PROJ_CONST_DEFN { return d->hubCRS_; }
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the transformation to the hub RS.
+ *
+ * @return transformation.
+ */
+const operation::TransformationNNPtr &
+BoundCRS::transformation() PROJ_CONST_DEFN {
+    return d->transformation_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a BoundCRS from a base CRS, a hub CRS and a
+ * transformation.
+ *
+ * @param baseCRSIn base CRS.
+ * @param hubCRSIn hub CRS.
+ * @param transformationIn transformation from base CRS to hub CRS.
+ * @return new BoundCRS.
+ */
+BoundCRSNNPtr
+BoundCRS::create(const CRSNNPtr &baseCRSIn, const CRSNNPtr &hubCRSIn,
+                 const operation::TransformationNNPtr &transformationIn) {
+    auto crs = BoundCRS::nn_make_shared<BoundCRS>(baseCRSIn, hubCRSIn,
+                                                  transformationIn);
+    crs->assignSelf(crs);
+    const auto &l_name = baseCRSIn->nameStr();
+    if (!l_name.empty()) {
+        crs->setProperties(util::PropertyMap().set(
+            common::IdentifiedObject::NAME_KEY, l_name));
+    }
+    return crs;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a BoundCRS from a base CRS and TOWGS84 parameters
+ *
+ * @param baseCRSIn base CRS.
+ * @param TOWGS84Parameters a vector of 3 or 7 double values representing WKT1
+ * TOWGS84 parameter.
+ * @return new BoundCRS.
+ */
+BoundCRSNNPtr
+BoundCRS::createFromTOWGS84(const CRSNNPtr &baseCRSIn,
+                            const std::vector<double> &TOWGS84Parameters) {
+
+    auto geodCRS = baseCRSIn->extractGeodeticCRS();
+    auto targetCRS =
+        geodCRS.get() == nullptr ||
+                dynamic_cast<const crs::GeographicCRS *>(geodCRS.get())
+            ? util::nn_static_pointer_cast<crs::CRS>(
+                  crs::GeographicCRS::EPSG_4326)
+            : util::nn_static_pointer_cast<crs::CRS>(
+                  crs::GeodeticCRS::EPSG_4978);
+    return create(
+        baseCRSIn, targetCRS,
+        operation::Transformation::createTOWGS84(baseCRSIn, TOWGS84Parameters));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a BoundCRS from a base CRS and nadgrids parameters
+ *
+ * @param baseCRSIn base CRS.
+ * @param filename Horizontal grid filename
+ * @return new BoundCRS.
+ */
+BoundCRSNNPtr BoundCRS::createFromNadgrids(const CRSNNPtr &baseCRSIn,
+                                           const std::string &filename) {
+    const CRSPtr sourceGeographicCRS = baseCRSIn->extractGeographicCRS();
+    auto transformationSourceCRS =
+        sourceGeographicCRS ? sourceGeographicCRS : baseCRSIn.as_nullable();
+    std::string transformationName = transformationSourceCRS->nameStr();
+    transformationName += " to WGS84";
+
+    return create(
+        baseCRSIn, GeographicCRS::EPSG_4326,
+        operation::Transformation::createNTv2(
+            util::PropertyMap().set(common::IdentifiedObject::NAME_KEY,
+                                    transformationName),
+            baseCRSIn, GeographicCRS::EPSG_4326, filename,
+            std::vector<metadata::PositionalAccuracyNNPtr>()));
+}
+
+// ---------------------------------------------------------------------------
+
+bool BoundCRS::isTOWGS84Compatible() const {
+    return dynamic_cast<GeodeticCRS *>(d->hubCRS().get()) != nullptr &&
+           ci_equal(d->hubCRS()->nameStr(), "WGS 84");
+}
+
+// ---------------------------------------------------------------------------
+
+std::string BoundCRS::getHDatumPROJ4GRIDS() const {
+    if (ci_equal(d->hubCRS()->nameStr(), "WGS 84")) {
+        return d->transformation()->getNTv2Filename();
+    }
+    return std::string();
+}
+
+// ---------------------------------------------------------------------------
+
+std::string BoundCRS::getVDatumPROJ4GRIDS() const {
+    if (dynamic_cast<VerticalCRS *>(d->baseCRS().get()) &&
+        ci_equal(d->hubCRS()->nameStr(), "WGS 84")) {
+        return d->transformation()->getHeightToGeographic3DFilename();
+    }
+    return std::string();
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void BoundCRS::_exportToWKT(io::WKTFormatter *formatter) const {
+    const bool isWKT2 = formatter->version() == io::WKTFormatter::Version::WKT2;
+    if (isWKT2) {
+        formatter->startNode(io::WKTConstants::BOUNDCRS, false);
+        formatter->startNode(io::WKTConstants::SOURCECRS, false);
+        d->baseCRS()->_exportToWKT(formatter);
+        formatter->endNode();
+        formatter->startNode(io::WKTConstants::TARGETCRS, false);
+        d->hubCRS()->_exportToWKT(formatter);
+        formatter->endNode();
+        formatter->setAbridgedTransformation(true);
+        d->transformation()->_exportToWKT(formatter);
+        formatter->setAbridgedTransformation(false);
+        formatter->endNode();
+    } else {
+
+        auto vdatumProj4GridName = getVDatumPROJ4GRIDS();
+        if (!vdatumProj4GridName.empty()) {
+            formatter->setVDatumExtension(vdatumProj4GridName);
+            d->baseCRS()->_exportToWKT(formatter);
+            formatter->setVDatumExtension(std::string());
+            return;
+        }
+
+        auto hdatumProj4GridName = getHDatumPROJ4GRIDS();
+        if (!hdatumProj4GridName.empty()) {
+            formatter->setHDatumExtension(hdatumProj4GridName);
+            d->baseCRS()->_exportToWKT(formatter);
+            formatter->setHDatumExtension(std::string());
+            return;
+        }
+
+        if (!isTOWGS84Compatible()) {
+            io::FormattingException::Throw(
+                "Cannot export BoundCRS with non-WGS 84 hub CRS in WKT1");
+        }
+        auto params = d->transformation()->getTOWGS84Parameters();
+        if (!formatter->useESRIDialect()) {
+            formatter->setTOWGS84Parameters(params);
+        }
+        d->baseCRS()->_exportToWKT(formatter);
+        formatter->setTOWGS84Parameters(std::vector<double>());
+    }
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+void BoundCRS::_exportToPROJString(
+    io::PROJStringFormatter *formatter) const // throw(io::FormattingException)
+{
+    if (formatter->convention() ==
+        io::PROJStringFormatter::Convention::PROJ_5) {
+        io::FormattingException::Throw(
+            "BoundCRS cannot be exported as a PROJ.5 string, but its baseCRS "
+            "might");
+    }
+
+    auto crs_exportable =
+        dynamic_cast<const io::IPROJStringExportable *>(d->baseCRS_.get());
+    if (!crs_exportable) {
+        io::FormattingException::Throw(
+            "baseCRS of BoundCRS cannot be exported as a PROJ string");
+    }
+
+    auto vdatumProj4GridName = getVDatumPROJ4GRIDS();
+    if (!vdatumProj4GridName.empty()) {
+        formatter->setVDatumExtension(vdatumProj4GridName);
+        crs_exportable->_exportToPROJString(formatter);
+        formatter->setVDatumExtension(std::string());
+    } else {
+        auto hdatumProj4GridName = getHDatumPROJ4GRIDS();
+        if (!hdatumProj4GridName.empty()) {
+            formatter->setHDatumExtension(hdatumProj4GridName);
+            crs_exportable->_exportToPROJString(formatter);
+            formatter->setHDatumExtension(std::string());
+        } else {
+            if (isTOWGS84Compatible()) {
+                auto params = transformation()->getTOWGS84Parameters();
+                formatter->setTOWGS84Parameters(params);
+            }
+            crs_exportable->_exportToPROJString(formatter);
+            formatter->setTOWGS84Parameters(std::vector<double>());
+        }
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+bool BoundCRS::_isEquivalentTo(const util::IComparable *other,
+                               util::IComparable::Criterion criterion) const {
+    auto otherBoundCRS = dynamic_cast<const BoundCRS *>(other);
+    if (otherBoundCRS == nullptr ||
+        (criterion == util::IComparable::Criterion::STRICT &&
+         !ObjectUsage::_isEquivalentTo(other, criterion))) {
+        return false;
+    }
+    const auto standardCriterion = getStandardCriterion(criterion);
+    return d->baseCRS_->_isEquivalentTo(otherBoundCRS->d->baseCRS_.get(),
+                                        criterion) &&
+           d->hubCRS_->_isEquivalentTo(otherBoundCRS->d->hubCRS_.get(),
+                                       criterion) &&
+           d->transformation_->_isEquivalentTo(
+               otherBoundCRS->d->transformation_.get(), standardCriterion);
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+std::list<std::pair<CRSNNPtr, int>>
+BoundCRS::_identify(const io::AuthorityFactoryPtr &authorityFactory) const {
+    typedef std::pair<CRSNNPtr, int> Pair;
+    std::list<Pair> res;
+    if (authorityFactory &&
+        d->hubCRS_->_isEquivalentTo(GeographicCRS::EPSG_4326.get(),
+                                    util::IComparable::Criterion::EQUIVALENT)) {
+        auto resTemp = d->baseCRS_->identify(authorityFactory);
+        for (const auto &pair : resTemp) {
+            const auto &candidateBaseCRS = pair.first;
+            auto projCRS =
+                dynamic_cast<const ProjectedCRS *>(candidateBaseCRS.get());
+            auto geodCRS = projCRS ? projCRS->baseCRS().as_nullable()
+                                   : util::nn_dynamic_pointer_cast<GeodeticCRS>(
+                                         candidateBaseCRS);
+            if (geodCRS) {
+                auto context = operation::CoordinateOperationContext::create(
+                    authorityFactory, nullptr, 0.0);
+                auto ops =
+                    operation::CoordinateOperationFactory::create()
+                        ->createOperations(NN_NO_CHECK(geodCRS),
+                                           GeographicCRS::EPSG_4326, context);
+                std::string refTransfPROJString;
+                bool refTransfPROJStringValid = false;
+                try {
+                    refTransfPROJString =
+                        d->transformation_->exportToPROJString(
+                            io::PROJStringFormatter::create().get());
+                    refTransfPROJStringValid = true;
+                    if (refTransfPROJString == "+proj=axisswap +order=2,1") {
+                        refTransfPROJString.clear();
+                    }
+                } catch (const std::exception &) {
+                }
+                bool foundOp = false;
+                for (const auto &op : ops) {
+                    std::string opTransfPROJString;
+                    bool opTransfPROJStringValid = false;
+                    if (op->nameStr().find("Null geographic") == 0) {
+                        if (isTOWGS84Compatible()) {
+                            auto params =
+                                transformation()->getTOWGS84Parameters();
+                            if (params ==
+                                std::vector<double>{0, 0, 0, 0, 0, 0, 0}) {
+                                res.emplace_back(create(candidateBaseCRS,
+                                                        d->hubCRS_,
+                                                        transformation()),
+                                                 pair.second);
+                                foundOp = true;
+                                break;
+                            }
+                        }
+                        continue;
+                    }
+                    try {
+                        opTransfPROJString = op->exportToPROJString(
+                            io::PROJStringFormatter::create().get());
+                        opTransfPROJStringValid = true;
+                    } catch (const std::exception &) {
+                    }
+                    if ((refTransfPROJStringValid && opTransfPROJStringValid &&
+                         refTransfPROJString == opTransfPROJString) ||
+                        op->_isEquivalentTo(
+                            d->transformation_.get(),
+                            util::IComparable::Criterion::EQUIVALENT)) {
+                        res.emplace_back(
+                            create(candidateBaseCRS, d->hubCRS_,
+                                   NN_NO_CHECK(util::nn_dynamic_pointer_cast<
+                                               operation::Transformation>(op))),
+                            pair.second);
+                        foundOp = true;
+                        break;
+                    }
+                }
+                if (!foundOp) {
+                    res.emplace_back(
+                        create(candidateBaseCRS, d->hubCRS_, transformation()),
+                        std::min(70, pair.second));
+                }
+            }
+        }
+    }
+    return res;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct DerivedGeodeticCRS::Private {};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+DerivedGeodeticCRS::~DerivedGeodeticCRS() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+DerivedGeodeticCRS::DerivedGeodeticCRS(
+    const GeodeticCRSNNPtr &baseCRSIn,
+    const operation::ConversionNNPtr &derivingConversionIn,
+    const cs::CartesianCSNNPtr &csIn)
+    : SingleCRS(baseCRSIn->datum(), baseCRSIn->datumEnsemble(), csIn),
+      GeodeticCRS(baseCRSIn->datum(), baseCRSIn->datumEnsemble(), csIn),
+      DerivedCRS(baseCRSIn, derivingConversionIn, csIn), d(nullptr) {}
+
+// ---------------------------------------------------------------------------
+
+DerivedGeodeticCRS::DerivedGeodeticCRS(
+    const GeodeticCRSNNPtr &baseCRSIn,
+    const operation::ConversionNNPtr &derivingConversionIn,
+    const cs::SphericalCSNNPtr &csIn)
+    : SingleCRS(baseCRSIn->datum(), baseCRSIn->datumEnsemble(), csIn),
+      GeodeticCRS(baseCRSIn->datum(), baseCRSIn->datumEnsemble(), csIn),
+      DerivedCRS(baseCRSIn, derivingConversionIn, csIn), d(nullptr) {}
+
+// ---------------------------------------------------------------------------
+
+DerivedGeodeticCRS::DerivedGeodeticCRS(const DerivedGeodeticCRS &other)
+    : SingleCRS(other), GeodeticCRS(other), DerivedCRS(other), d(nullptr) {}
+
+// ---------------------------------------------------------------------------
+
+CRSNNPtr DerivedGeodeticCRS::_shallowClone() const {
+    auto crs(DerivedGeodeticCRS::nn_make_shared<DerivedGeodeticCRS>(*this));
+    crs->assignSelf(crs);
+    crs->setDerivingConversionCRS();
+    return crs;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the base CRS (a GeodeticCRS) of a DerivedGeodeticCRS.
+ *
+ * @return the base CRS.
+ */
+const GeodeticCRSNNPtr DerivedGeodeticCRS::baseCRS() const {
+    return NN_NO_CHECK(util::nn_dynamic_pointer_cast<GeodeticCRS>(
+        DerivedCRS::getPrivate()->baseCRS_));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a DerivedGeodeticCRS from a base CRS, a deriving
+ * conversion and a cs::CartesianCS.
+ *
+ * @param properties See \ref general_properties.
+ * At minimum the name should be defined.
+ * @param baseCRSIn base CRS.
+ * @param derivingConversionIn the deriving conversion from the base CRS to this
+ * CRS.
+ * @param csIn the coordinate system.
+ * @return new DerivedGeodeticCRS.
+ */
+DerivedGeodeticCRSNNPtr DerivedGeodeticCRS::create(
+    const util::PropertyMap &properties, const GeodeticCRSNNPtr &baseCRSIn,
+    const operation::ConversionNNPtr &derivingConversionIn,
+    const cs::CartesianCSNNPtr &csIn) {
+    auto crs(DerivedGeodeticCRS::nn_make_shared<DerivedGeodeticCRS>(
+        baseCRSIn, derivingConversionIn, csIn));
+    crs->assignSelf(crs);
+    crs->setProperties(properties);
+    crs->setDerivingConversionCRS();
+    return crs;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a DerivedGeodeticCRS from a base CRS, a deriving
+ * conversion and a cs::SphericalCS.
+ *
+ * @param properties See \ref general_properties.
+ * At minimum the name should be defined.
+ * @param baseCRSIn base CRS.
+ * @param derivingConversionIn the deriving conversion from the base CRS to this
+ * CRS.
+ * @param csIn the coordinate system.
+ * @return new DerivedGeodeticCRS.
+ */
+DerivedGeodeticCRSNNPtr DerivedGeodeticCRS::create(
+    const util::PropertyMap &properties, const GeodeticCRSNNPtr &baseCRSIn,
+    const operation::ConversionNNPtr &derivingConversionIn,
+    const cs::SphericalCSNNPtr &csIn) {
+    auto crs(DerivedGeodeticCRS::nn_make_shared<DerivedGeodeticCRS>(
+        baseCRSIn, derivingConversionIn, csIn));
+    crs->assignSelf(crs);
+    crs->setProperties(properties);
+    crs->setDerivingConversionCRS();
+    return crs;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void DerivedGeodeticCRS::_exportToWKT(io::WKTFormatter *formatter) const {
+    const bool isWKT2 = formatter->version() == io::WKTFormatter::Version::WKT2;
+    if (!isWKT2) {
+        io::FormattingException::Throw(
+            "DerivedGeodeticCRS can only be exported to WKT2");
+    }
+    formatter->startNode(io::WKTConstants::GEODCRS, !identifiers().empty());
+    formatter->addQuotedString(nameStr());
+
+    auto l_baseCRS = baseCRS();
+    formatter->startNode((formatter->use2018Keywords() &&
+                          dynamic_cast<const GeographicCRS *>(l_baseCRS.get()))
+                             ? io::WKTConstants::BASEGEOGCRS
+                             : io::WKTConstants::BASEGEODCRS,
+                         !baseCRS()->identifiers().empty());
+    formatter->addQuotedString(l_baseCRS->nameStr());
+    auto l_datum = l_baseCRS->datum();
+    if (l_datum) {
+        l_datum->_exportToWKT(formatter);
+    } else {
+        auto l_datumEnsemble = datumEnsemble();
+        assert(l_datumEnsemble);
+        l_datumEnsemble->_exportToWKT(formatter);
+    }
+    l_baseCRS->primeMeridian()->_exportToWKT(formatter);
+    formatter->endNode();
+
+    formatter->setUseDerivingConversion(true);
+    derivingConversionRef()->_exportToWKT(formatter);
+    formatter->setUseDerivingConversion(false);
+
+    coordinateSystem()->_exportToWKT(formatter);
+    ObjectUsage::baseExportToWKT(formatter);
+    formatter->endNode();
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+void DerivedGeodeticCRS::_exportToPROJString(
+    io::PROJStringFormatter *formatter) const // throw(io::FormattingException)
+{
+    baseExportToPROJString(formatter);
+}
+
+// ---------------------------------------------------------------------------
+
+bool DerivedGeodeticCRS::_isEquivalentTo(
+    const util::IComparable *other,
+    util::IComparable::Criterion criterion) const {
+    auto otherDerivedCRS = dynamic_cast<const DerivedGeodeticCRS *>(other);
+    return otherDerivedCRS != nullptr &&
+           DerivedCRS::_isEquivalentTo(other, criterion);
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+std::list<std::pair<CRSNNPtr, int>>
+DerivedGeodeticCRS::_identify(const io::AuthorityFactoryPtr &factory) const {
+    return CRS::_identify(factory);
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct DerivedGeographicCRS::Private {};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+DerivedGeographicCRS::~DerivedGeographicCRS() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+DerivedGeographicCRS::DerivedGeographicCRS(
+    const GeodeticCRSNNPtr &baseCRSIn,
+    const operation::ConversionNNPtr &derivingConversionIn,
+    const cs::EllipsoidalCSNNPtr &csIn)
+    : SingleCRS(baseCRSIn->datum(), baseCRSIn->datumEnsemble(), csIn),
+      GeographicCRS(baseCRSIn->datum(), baseCRSIn->datumEnsemble(), csIn),
+      DerivedCRS(baseCRSIn, derivingConversionIn, csIn), d(nullptr) {}
+
+// ---------------------------------------------------------------------------
+
+DerivedGeographicCRS::DerivedGeographicCRS(const DerivedGeographicCRS &other)
+    : SingleCRS(other), GeographicCRS(other), DerivedCRS(other), d(nullptr) {}
+
+// ---------------------------------------------------------------------------
+
+CRSNNPtr DerivedGeographicCRS::_shallowClone() const {
+    auto crs(DerivedGeographicCRS::nn_make_shared<DerivedGeographicCRS>(*this));
+    crs->assignSelf(crs);
+    crs->setDerivingConversionCRS();
+    return crs;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the base CRS (a GeodeticCRS) of a DerivedGeographicCRS.
+ *
+ * @return the base CRS.
+ */
+const GeodeticCRSNNPtr DerivedGeographicCRS::baseCRS() const {
+    return NN_NO_CHECK(util::nn_dynamic_pointer_cast<GeodeticCRS>(
+        DerivedCRS::getPrivate()->baseCRS_));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a DerivedGeographicCRS from a base CRS, a deriving
+ * conversion and a cs::EllipsoidalCS.
+ *
+ * @param properties See \ref general_properties.
+ * At minimum the name should be defined.
+ * @param baseCRSIn base CRS.
+ * @param derivingConversionIn the deriving conversion from the base CRS to this
+ * CRS.
+ * @param csIn the coordinate system.
+ * @return new DerivedGeographicCRS.
+ */
+DerivedGeographicCRSNNPtr DerivedGeographicCRS::create(
+    const util::PropertyMap &properties, const GeodeticCRSNNPtr &baseCRSIn,
+    const operation::ConversionNNPtr &derivingConversionIn,
+    const cs::EllipsoidalCSNNPtr &csIn) {
+    auto crs(DerivedGeographicCRS::nn_make_shared<DerivedGeographicCRS>(
+        baseCRSIn, derivingConversionIn, csIn));
+    crs->assignSelf(crs);
+    crs->setProperties(properties);
+    crs->setDerivingConversionCRS();
+    return crs;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void DerivedGeographicCRS::_exportToWKT(io::WKTFormatter *formatter) const {
+    const bool isWKT2 = formatter->version() == io::WKTFormatter::Version::WKT2;
+    if (!isWKT2) {
+        io::FormattingException::Throw(
+            "DerivedGeographicCRS can only be exported to WKT2");
+    }
+    formatter->startNode(formatter->use2018Keywords()
+                             ? io::WKTConstants::GEOGCRS
+                             : io::WKTConstants::GEODCRS,
+                         !identifiers().empty());
+    formatter->addQuotedString(nameStr());
+
+    auto l_baseCRS = baseCRS();
+    formatter->startNode((formatter->use2018Keywords() &&
+                          dynamic_cast<const GeographicCRS *>(l_baseCRS.get()))
+                             ? io::WKTConstants::BASEGEOGCRS
+                             : io::WKTConstants::BASEGEODCRS,
+                         !l_baseCRS->identifiers().empty());
+    formatter->addQuotedString(l_baseCRS->nameStr());
+    l_baseCRS->exportDatumOrDatumEnsembleToWkt(formatter);
+    l_baseCRS->primeMeridian()->_exportToWKT(formatter);
+    formatter->endNode();
+
+    formatter->setUseDerivingConversion(true);
+    derivingConversionRef()->_exportToWKT(formatter);
+    formatter->setUseDerivingConversion(false);
+
+    coordinateSystem()->_exportToWKT(formatter);
+    ObjectUsage::baseExportToWKT(formatter);
+    formatter->endNode();
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+void DerivedGeographicCRS::_exportToPROJString(
+    io::PROJStringFormatter *formatter) const // throw(io::FormattingException)
+{
+    baseExportToPROJString(formatter);
+}
+
+// ---------------------------------------------------------------------------
+
+bool DerivedGeographicCRS::_isEquivalentTo(
+    const util::IComparable *other,
+    util::IComparable::Criterion criterion) const {
+    auto otherDerivedCRS = dynamic_cast<const DerivedGeographicCRS *>(other);
+    return otherDerivedCRS != nullptr &&
+           DerivedCRS::_isEquivalentTo(other, criterion);
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+std::list<std::pair<CRSNNPtr, int>>
+DerivedGeographicCRS::_identify(const io::AuthorityFactoryPtr &factory) const {
+    return CRS::_identify(factory);
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct DerivedProjectedCRS::Private {};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+DerivedProjectedCRS::~DerivedProjectedCRS() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+DerivedProjectedCRS::DerivedProjectedCRS(
+    const ProjectedCRSNNPtr &baseCRSIn,
+    const operation::ConversionNNPtr &derivingConversionIn,
+    const cs::CoordinateSystemNNPtr &csIn)
+    : SingleCRS(baseCRSIn->datum(), baseCRSIn->datumEnsemble(), csIn),
+      DerivedCRS(baseCRSIn, derivingConversionIn, csIn), d(nullptr) {}
+
+// ---------------------------------------------------------------------------
+
+DerivedProjectedCRS::DerivedProjectedCRS(const DerivedProjectedCRS &other)
+    : SingleCRS(other), DerivedCRS(other), d(nullptr) {}
+
+// ---------------------------------------------------------------------------
+
+CRSNNPtr DerivedProjectedCRS::_shallowClone() const {
+    auto crs(DerivedProjectedCRS::nn_make_shared<DerivedProjectedCRS>(*this));
+    crs->assignSelf(crs);
+    crs->setDerivingConversionCRS();
+    return crs;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the base CRS (a ProjectedCRS) of a DerivedProjectedCRS.
+ *
+ * @return the base CRS.
+ */
+const ProjectedCRSNNPtr DerivedProjectedCRS::baseCRS() const {
+    return NN_NO_CHECK(util::nn_dynamic_pointer_cast<ProjectedCRS>(
+        DerivedCRS::getPrivate()->baseCRS_));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a DerivedProjectedCRS from a base CRS, a deriving
+ * conversion and a cs::CS.
+ *
+ * @param properties See \ref general_properties.
+ * At minimum the name should be defined.
+ * @param baseCRSIn base CRS.
+ * @param derivingConversionIn the deriving conversion from the base CRS to this
+ * CRS.
+ * @param csIn the coordinate system.
+ * @return new DerivedProjectedCRS.
+ */
+DerivedProjectedCRSNNPtr DerivedProjectedCRS::create(
+    const util::PropertyMap &properties, const ProjectedCRSNNPtr &baseCRSIn,
+    const operation::ConversionNNPtr &derivingConversionIn,
+    const cs::CoordinateSystemNNPtr &csIn) {
+    auto crs(DerivedProjectedCRS::nn_make_shared<DerivedProjectedCRS>(
+        baseCRSIn, derivingConversionIn, csIn));
+    crs->assignSelf(crs);
+    crs->setProperties(properties);
+    crs->setDerivingConversionCRS();
+    return crs;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void DerivedProjectedCRS::_exportToWKT(io::WKTFormatter *formatter) const {
+    const bool isWKT2 = formatter->version() == io::WKTFormatter::Version::WKT2;
+    if (!isWKT2 || !formatter->use2018Keywords()) {
+        io::FormattingException::Throw(
+            "DerivedProjectedCRS can only be exported to WKT2:2018");
+    }
+    formatter->startNode(io::WKTConstants::DERIVEDPROJCRS,
+                         !identifiers().empty());
+    formatter->addQuotedString(nameStr());
+
+    {
+        auto l_baseProjCRS = baseCRS();
+        formatter->startNode(io::WKTConstants::BASEPROJCRS,
+                             !l_baseProjCRS->identifiers().empty());
+        formatter->addQuotedString(l_baseProjCRS->nameStr());
+
+        auto l_baseGeodCRS = l_baseProjCRS->baseCRS();
+        auto &geodeticCRSAxisList =
+            l_baseGeodCRS->coordinateSystem()->axisList();
+
+        formatter->startNode(
+            dynamic_cast<const GeographicCRS *>(l_baseGeodCRS.get())
+                ? io::WKTConstants::BASEGEOGCRS
+                : io::WKTConstants::BASEGEODCRS,
+            !l_baseGeodCRS->identifiers().empty());
+        formatter->addQuotedString(l_baseGeodCRS->nameStr());
+        l_baseGeodCRS->exportDatumOrDatumEnsembleToWkt(formatter);
+        // insert ellipsoidal cs unit when the units of the map
+        // projection angular parameters are not explicitly given within those
+        // parameters. See
+        // http://docs.opengeospatial.org/is/12-063r5/12-063r5.html#61
+        if (formatter->primeMeridianOrParameterUnitOmittedIfSameAsAxis() &&
+            !geodeticCRSAxisList.empty()) {
+            geodeticCRSAxisList[0]->unit()._exportToWKT(formatter);
+        }
+        l_baseGeodCRS->primeMeridian()->_exportToWKT(formatter);
+        formatter->endNode();
+
+        l_baseProjCRS->derivingConversionRef()->_exportToWKT(formatter);
+        formatter->endNode();
+    }
+
+    formatter->setUseDerivingConversion(true);
+    derivingConversionRef()->_exportToWKT(formatter);
+    formatter->setUseDerivingConversion(false);
+
+    coordinateSystem()->_exportToWKT(formatter);
+    ObjectUsage::baseExportToWKT(formatter);
+    formatter->endNode();
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+void DerivedProjectedCRS::_exportToPROJString(
+    io::PROJStringFormatter *formatter) const // throw(io::FormattingException)
+{
+    baseExportToPROJString(formatter);
+}
+
+// ---------------------------------------------------------------------------
+
+bool DerivedProjectedCRS::_isEquivalentTo(
+    const util::IComparable *other,
+    util::IComparable::Criterion criterion) const {
+    auto otherDerivedCRS = dynamic_cast<const DerivedProjectedCRS *>(other);
+    return otherDerivedCRS != nullptr &&
+           DerivedCRS::_isEquivalentTo(other, criterion);
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct TemporalCRS::Private {};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+TemporalCRS::~TemporalCRS() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+TemporalCRS::TemporalCRS(const datum::TemporalDatumNNPtr &datumIn,
+                         const cs::TemporalCSNNPtr &csIn)
+    : SingleCRS(datumIn.as_nullable(), nullptr, csIn), d(nullptr) {}
+
+// ---------------------------------------------------------------------------
+
+TemporalCRS::TemporalCRS(const TemporalCRS &other)
+    : SingleCRS(other), d(nullptr) {}
+
+// ---------------------------------------------------------------------------
+
+CRSNNPtr TemporalCRS::_shallowClone() const {
+    auto crs(TemporalCRS::nn_make_shared<TemporalCRS>(*this));
+    crs->assignSelf(crs);
+    return crs;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the datum::TemporalDatum associated with the CRS.
+ *
+ * @return a TemporalDatum
+ */
+const datum::TemporalDatumNNPtr TemporalCRS::datum() const {
+    return NN_NO_CHECK(std::static_pointer_cast<datum::TemporalDatum>(
+        SingleCRS::getPrivate()->datum));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the cs::TemporalCS associated with the CRS.
+ *
+ * @return a TemporalCS
+ */
+const cs::TemporalCSNNPtr TemporalCRS::coordinateSystem() const {
+    return util::nn_static_pointer_cast<cs::TemporalCS>(
+        SingleCRS::getPrivate()->coordinateSystem);
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a TemporalCRS from a datum and a coordinate system.
+ *
+ * @param properties See \ref general_properties.
+ * At minimum the name should be defined.
+ * @param datumIn the datum.
+ * @param csIn the coordinate system.
+ * @return new TemporalCRS.
+ */
+TemporalCRSNNPtr TemporalCRS::create(const util::PropertyMap &properties,
+                                     const datum::TemporalDatumNNPtr &datumIn,
+                                     const cs::TemporalCSNNPtr &csIn) {
+    auto crs(TemporalCRS::nn_make_shared<TemporalCRS>(datumIn, csIn));
+    crs->assignSelf(crs);
+    crs->setProperties(properties);
+    return crs;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void TemporalCRS::_exportToWKT(io::WKTFormatter *formatter) const {
+    const bool isWKT2 = formatter->version() == io::WKTFormatter::Version::WKT2;
+    if (!isWKT2) {
+        io::FormattingException::Throw(
+            "TemporalCRS can only be exported to WKT2");
+    }
+    formatter->startNode(io::WKTConstants::TIMECRS, !identifiers().empty());
+    formatter->addQuotedString(nameStr());
+    datum()->_exportToWKT(formatter);
+    coordinateSystem()->_exportToWKT(formatter);
+    ObjectUsage::baseExportToWKT(formatter);
+    formatter->endNode();
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+bool TemporalCRS::_isEquivalentTo(
+    const util::IComparable *other,
+    util::IComparable::Criterion criterion) const {
+    auto otherTemporalCRS = dynamic_cast<const TemporalCRS *>(other);
+    return otherTemporalCRS != nullptr &&
+           SingleCRS::baseIsEquivalentTo(other, criterion);
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct EngineeringCRS::Private {
+    bool forceOutputCS_ = false;
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+EngineeringCRS::~EngineeringCRS() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+EngineeringCRS::EngineeringCRS(const datum::EngineeringDatumNNPtr &datumIn,
+                               const cs::CoordinateSystemNNPtr &csIn)
+    : SingleCRS(datumIn.as_nullable(), nullptr, csIn),
+      d(internal::make_unique<Private>()) {}
+
+// ---------------------------------------------------------------------------
+
+EngineeringCRS::EngineeringCRS(const EngineeringCRS &other)
+    : SingleCRS(other), d(internal::make_unique<Private>(*(other.d))) {}
+
+// ---------------------------------------------------------------------------
+
+CRSNNPtr EngineeringCRS::_shallowClone() const {
+    auto crs(EngineeringCRS::nn_make_shared<EngineeringCRS>(*this));
+    crs->assignSelf(crs);
+    return crs;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the datum::EngineeringDatum associated with the CRS.
+ *
+ * @return a EngineeringDatum
+ */
+const datum::EngineeringDatumNNPtr EngineeringCRS::datum() const {
+    return NN_NO_CHECK(std::static_pointer_cast<datum::EngineeringDatum>(
+        SingleCRS::getPrivate()->datum));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a EngineeringCRS from a datum and a coordinate system.
+ *
+ * @param properties See \ref general_properties.
+ * At minimum the name should be defined.
+ * @param datumIn the datum.
+ * @param csIn the coordinate system.
+ * @return new EngineeringCRS.
+ */
+EngineeringCRSNNPtr
+EngineeringCRS::create(const util::PropertyMap &properties,
+                       const datum::EngineeringDatumNNPtr &datumIn,
+                       const cs::CoordinateSystemNNPtr &csIn) {
+    auto crs(EngineeringCRS::nn_make_shared<EngineeringCRS>(datumIn, csIn));
+    crs->assignSelf(crs);
+    crs->setProperties(properties);
+
+    const auto pVal = properties.get("FORCE_OUTPUT_CS");
+    if (pVal) {
+        if (const auto genVal =
+                dynamic_cast<const util::BoxedValue *>(pVal->get())) {
+            if (genVal->type() == util::BoxedValue::Type::BOOLEAN &&
+                genVal->booleanValue()) {
+                crs->d->forceOutputCS_ = true;
+            }
+        }
+    }
+
+    return crs;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void EngineeringCRS::_exportToWKT(io::WKTFormatter *formatter) const {
+    const bool isWKT2 = formatter->version() == io::WKTFormatter::Version::WKT2;
+    formatter->startNode(isWKT2 ? io::WKTConstants::ENGCRS
+                                : io::WKTConstants::LOCAL_CS,
+                         !identifiers().empty());
+    formatter->addQuotedString(nameStr());
+    if (isWKT2 || !datum()->nameStr().empty()) {
+        datum()->_exportToWKT(formatter);
+        coordinateSystem()->_exportToWKT(formatter);
+    }
+    if (!isWKT2 && d->forceOutputCS_) {
+        coordinateSystem()->axisList()[0]->unit()._exportToWKT(formatter);
+    }
+    ObjectUsage::baseExportToWKT(formatter);
+    formatter->endNode();
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+bool EngineeringCRS::_isEquivalentTo(
+    const util::IComparable *other,
+    util::IComparable::Criterion criterion) const {
+    auto otherEngineeringCRS = dynamic_cast<const EngineeringCRS *>(other);
+    return otherEngineeringCRS != nullptr &&
+           SingleCRS::baseIsEquivalentTo(other, criterion);
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct ParametricCRS::Private {};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+ParametricCRS::~ParametricCRS() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+ParametricCRS::ParametricCRS(const datum::ParametricDatumNNPtr &datumIn,
+                             const cs::ParametricCSNNPtr &csIn)
+    : SingleCRS(datumIn.as_nullable(), nullptr, csIn), d(nullptr) {}
+
+// ---------------------------------------------------------------------------
+
+ParametricCRS::ParametricCRS(const ParametricCRS &other)
+    : SingleCRS(other), d(nullptr) {}
+
+// ---------------------------------------------------------------------------
+
+CRSNNPtr ParametricCRS::_shallowClone() const {
+    auto crs(ParametricCRS::nn_make_shared<ParametricCRS>(*this));
+    crs->assignSelf(crs);
+    return crs;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the datum::ParametricDatum associated with the CRS.
+ *
+ * @return a ParametricDatum
+ */
+const datum::ParametricDatumNNPtr ParametricCRS::datum() const {
+    return NN_NO_CHECK(std::static_pointer_cast<datum::ParametricDatum>(
+        SingleCRS::getPrivate()->datum));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the cs::TemporalCS associated with the CRS.
+ *
+ * @return a TemporalCS
+ */
+const cs::ParametricCSNNPtr ParametricCRS::coordinateSystem() const {
+    return util::nn_static_pointer_cast<cs::ParametricCS>(
+        SingleCRS::getPrivate()->coordinateSystem);
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ParametricCRS from a datum and a coordinate system.
+ *
+ * @param properties See \ref general_properties.
+ * At minimum the name should be defined.
+ * @param datumIn the datum.
+ * @param csIn the coordinate system.
+ * @return new ParametricCRS.
+ */
+ParametricCRSNNPtr
+ParametricCRS::create(const util::PropertyMap &properties,
+                      const datum::ParametricDatumNNPtr &datumIn,
+                      const cs::ParametricCSNNPtr &csIn) {
+    auto crs(ParametricCRS::nn_make_shared<ParametricCRS>(datumIn, csIn));
+    crs->assignSelf(crs);
+    crs->setProperties(properties);
+    return crs;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void ParametricCRS::_exportToWKT(io::WKTFormatter *formatter) const {
+    const bool isWKT2 = formatter->version() == io::WKTFormatter::Version::WKT2;
+    if (!isWKT2) {
+        io::FormattingException::Throw(
+            "ParametricCRS can only be exported to WKT2");
+    }
+    formatter->startNode(io::WKTConstants::PARAMETRICCRS,
+                         !identifiers().empty());
+    formatter->addQuotedString(nameStr());
+    datum()->_exportToWKT(formatter);
+    coordinateSystem()->_exportToWKT(formatter);
+    ObjectUsage::baseExportToWKT(formatter);
+    formatter->endNode();
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+bool ParametricCRS::_isEquivalentTo(
+    const util::IComparable *other,
+    util::IComparable::Criterion criterion) const {
+    auto otherParametricCRS = dynamic_cast<const ParametricCRS *>(other);
+    return otherParametricCRS != nullptr &&
+           SingleCRS::baseIsEquivalentTo(other, criterion);
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct DerivedVerticalCRS::Private {};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+DerivedVerticalCRS::~DerivedVerticalCRS() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+DerivedVerticalCRS::DerivedVerticalCRS(
+    const VerticalCRSNNPtr &baseCRSIn,
+    const operation::ConversionNNPtr &derivingConversionIn,
+    const cs::VerticalCSNNPtr &csIn)
+    : SingleCRS(baseCRSIn->datum(), baseCRSIn->datumEnsemble(), csIn),
+      VerticalCRS(baseCRSIn->datum(), baseCRSIn->datumEnsemble(), csIn),
+      DerivedCRS(baseCRSIn, derivingConversionIn, csIn), d(nullptr) {}
+
+// ---------------------------------------------------------------------------
+
+DerivedVerticalCRS::DerivedVerticalCRS(const DerivedVerticalCRS &other)
+    : SingleCRS(other), VerticalCRS(other), DerivedCRS(other), d(nullptr) {}
+
+// ---------------------------------------------------------------------------
+
+CRSNNPtr DerivedVerticalCRS::_shallowClone() const {
+    auto crs(DerivedVerticalCRS::nn_make_shared<DerivedVerticalCRS>(*this));
+    crs->assignSelf(crs);
+    crs->setDerivingConversionCRS();
+    return crs;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the base CRS (a VerticalCRS) of a DerivedVerticalCRS.
+ *
+ * @return the base CRS.
+ */
+const VerticalCRSNNPtr DerivedVerticalCRS::baseCRS() const {
+    return NN_NO_CHECK(util::nn_dynamic_pointer_cast<VerticalCRS>(
+        DerivedCRS::getPrivate()->baseCRS_));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a DerivedVerticalCRS from a base CRS, a deriving
+ * conversion and a cs::VerticalCS.
+ *
+ * @param properties See \ref general_properties.
+ * At minimum the name should be defined.
+ * @param baseCRSIn base CRS.
+ * @param derivingConversionIn the deriving conversion from the base CRS to this
+ * CRS.
+ * @param csIn the coordinate system.
+ * @return new DerivedVerticalCRS.
+ */
+DerivedVerticalCRSNNPtr DerivedVerticalCRS::create(
+    const util::PropertyMap &properties, const VerticalCRSNNPtr &baseCRSIn,
+    const operation::ConversionNNPtr &derivingConversionIn,
+    const cs::VerticalCSNNPtr &csIn) {
+    auto crs(DerivedVerticalCRS::nn_make_shared<DerivedVerticalCRS>(
+        baseCRSIn, derivingConversionIn, csIn));
+    crs->assignSelf(crs);
+    crs->setProperties(properties);
+    crs->setDerivingConversionCRS();
+    return crs;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void DerivedVerticalCRS::_exportToWKT(io::WKTFormatter *formatter) const {
+    const bool isWKT2 = formatter->version() == io::WKTFormatter::Version::WKT2;
+    if (!isWKT2) {
+        io::FormattingException::Throw(
+            "DerivedVerticalCRS can only be exported to WKT2");
+    }
+    baseExportToWKT(formatter, io::WKTConstants::VERTCRS,
+                    io::WKTConstants::BASEVERTCRS);
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+void DerivedVerticalCRS::_exportToPROJString(
+    io::PROJStringFormatter *formatter) const // throw(io::FormattingException)
+{
+    baseExportToPROJString(formatter);
+}
+
+// ---------------------------------------------------------------------------
+
+bool DerivedVerticalCRS::_isEquivalentTo(
+    const util::IComparable *other,
+    util::IComparable::Criterion criterion) const {
+    auto otherDerivedCRS = dynamic_cast<const DerivedVerticalCRS *>(other);
+    return otherDerivedCRS != nullptr &&
+           DerivedCRS::_isEquivalentTo(other, criterion);
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+std::list<std::pair<CRSNNPtr, int>>
+DerivedVerticalCRS::_identify(const io::AuthorityFactoryPtr &factory) const {
+    return CRS::_identify(factory);
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+template <class DerivedCRSTraits>
+struct DerivedCRSTemplate<DerivedCRSTraits>::Private {};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+template <class DerivedCRSTraits>
+DerivedCRSTemplate<DerivedCRSTraits>::~DerivedCRSTemplate() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+template <class DerivedCRSTraits>
+DerivedCRSTemplate<DerivedCRSTraits>::DerivedCRSTemplate(
+    const BaseNNPtr &baseCRSIn,
+    const operation::ConversionNNPtr &derivingConversionIn, const CSNNPtr &csIn)
+    : SingleCRS(baseCRSIn->datum().as_nullable(), nullptr, csIn),
+      BaseType(baseCRSIn->datum(), csIn),
+      DerivedCRS(baseCRSIn, derivingConversionIn, csIn), d(nullptr) {}
+
+// ---------------------------------------------------------------------------
+
+template <class DerivedCRSTraits>
+DerivedCRSTemplate<DerivedCRSTraits>::DerivedCRSTemplate(
+    const DerivedCRSTemplate &other)
+    : SingleCRS(other), BaseType(other), DerivedCRS(other), d(nullptr) {}
+
+// ---------------------------------------------------------------------------
+
+template <class DerivedCRSTraits>
+const typename DerivedCRSTemplate<DerivedCRSTraits>::BaseNNPtr
+DerivedCRSTemplate<DerivedCRSTraits>::baseCRS() const {
+    auto l_baseCRS = DerivedCRS::getPrivate()->baseCRS_;
+    return NN_NO_CHECK(util::nn_dynamic_pointer_cast<BaseType>(l_baseCRS));
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+template <class DerivedCRSTraits>
+CRSNNPtr DerivedCRSTemplate<DerivedCRSTraits>::_shallowClone() const {
+    auto crs(DerivedCRSTemplate::nn_make_shared<DerivedCRSTemplate>(*this));
+    crs->assignSelf(crs);
+    crs->setDerivingConversionCRS();
+    return crs;
+}
+
+// ---------------------------------------------------------------------------
+
+template <class DerivedCRSTraits>
+typename DerivedCRSTemplate<DerivedCRSTraits>::NNPtr
+DerivedCRSTemplate<DerivedCRSTraits>::create(
+    const util::PropertyMap &properties, const BaseNNPtr &baseCRSIn,
+    const operation::ConversionNNPtr &derivingConversionIn,
+    const CSNNPtr &csIn) {
+    auto crs(DerivedCRSTemplate::nn_make_shared<DerivedCRSTemplate>(
+        baseCRSIn, derivingConversionIn, csIn));
+    crs->assignSelf(crs);
+    crs->setProperties(properties);
+    crs->setDerivingConversionCRS();
+    return crs;
+}
+
+// ---------------------------------------------------------------------------
+
+static void DerivedCRSTemplateCheckExportToWKT(io::WKTFormatter *&formatter,
+                                               const std::string &crsName,
+                                               bool wkt2_2018_only) {
+    const bool isWKT2 = formatter->version() == io::WKTFormatter::Version::WKT2;
+    if (!isWKT2 || (wkt2_2018_only && !formatter->use2018Keywords())) {
+        io::FormattingException::Throw(crsName +
+                                       " can only be exported to WKT2" +
+                                       (wkt2_2018_only ? ":2018" : ""));
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+template <class DerivedCRSTraits>
+void DerivedCRSTemplate<DerivedCRSTraits>::_exportToWKT(
+    io::WKTFormatter *formatter) const {
+    DerivedCRSTemplateCheckExportToWKT(formatter, DerivedCRSTraits::CRSName(),
+                                       DerivedCRSTraits::wkt2_2018_only);
+    baseExportToWKT(formatter, DerivedCRSTraits::WKTKeyword(),
+                    DerivedCRSTraits::WKTBaseKeyword());
+}
+
+// ---------------------------------------------------------------------------
+
+template <class DerivedCRSTraits>
+bool DerivedCRSTemplate<DerivedCRSTraits>::_isEquivalentTo(
+    const util::IComparable *other,
+    util::IComparable::Criterion criterion) const {
+    auto otherDerivedCRS = dynamic_cast<const DerivedCRSTemplate *>(other);
+    return otherDerivedCRS != nullptr &&
+           DerivedCRS::_isEquivalentTo(other, criterion);
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static const std::string STRING_DerivedEngineeringCRS("DerivedEngineeringCRS");
+const std::string &DerivedEngineeringCRSTraits::CRSName() {
+    return STRING_DerivedEngineeringCRS;
+}
+const std::string &DerivedEngineeringCRSTraits::WKTKeyword() {
+    return io::WKTConstants::ENGCRS;
+}
+const std::string &DerivedEngineeringCRSTraits::WKTBaseKeyword() {
+    return io::WKTConstants::BASEENGCRS;
+}
+
+template class DerivedCRSTemplate<DerivedEngineeringCRSTraits>;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static const std::string STRING_DerivedParametricCRS("DerivedParametricCRS");
+const std::string &DerivedParametricCRSTraits::CRSName() {
+    return STRING_DerivedParametricCRS;
+}
+const std::string &DerivedParametricCRSTraits::WKTKeyword() {
+    return io::WKTConstants::PARAMETRICCRS;
+}
+const std::string &DerivedParametricCRSTraits::WKTBaseKeyword() {
+    return io::WKTConstants::BASEPARAMCRS;
+}
+
+template class DerivedCRSTemplate<DerivedParametricCRSTraits>;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static const std::string STRING_DerivedTemporalCRS("DerivedTemporalCRS");
+const std::string &DerivedTemporalCRSTraits::CRSName() {
+    return STRING_DerivedTemporalCRS;
+}
+const std::string &DerivedTemporalCRSTraits::WKTKeyword() {
+    return io::WKTConstants::TIMECRS;
+}
+const std::string &DerivedTemporalCRSTraits::WKTBaseKeyword() {
+    return io::WKTConstants::BASETIMECRS;
+}
+
+template class DerivedCRSTemplate<DerivedTemporalCRSTraits>;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+} // namespace crs
+NS_PROJ_END
diff --git a/src/iso19111/datum.cpp b/src/iso19111/datum.cpp
new file mode 100644
index 00000000..16e86296
--- /dev/null
+++ b/src/iso19111/datum.cpp
@@ -0,0 +1,1996 @@
+/******************************************************************************
+ *
+ * Project:  PROJ
+ * Purpose:  ISO19111:2018 implementation
+ * Author:   Even Rouault <even dot rouault at spatialys dot com>
+ *
+ ******************************************************************************
+ * Copyright (c) 2018, Even Rouault <even dot rouault at spatialys dot com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ ****************************************************************************/
+
+#ifndef FROM_PROJ_CPP
+#define FROM_PROJ_CPP
+#endif
+
+#include "proj/datum.hpp"
+#include "proj/common.hpp"
+#include "proj/io.hpp"
+#include "proj/metadata.hpp"
+#include "proj/util.hpp"
+
+#include "proj/internal/internal.hpp"
+#include "proj/internal/io_internal.hpp"
+
+// PROJ include order is sensitive
+// clang-format off
+#include "proj.h"
+#include "projects.h"
+#include "proj_api.h"
+// clang-format on
+
+#include <cmath>
+#include <cstdlib>
+#include <memory>
+#include <string>
+
+using namespace NS_PROJ::internal;
+
+#if 0
+namespace dropbox{ namespace oxygen {
+template<> nn<NS_PROJ::datum::DatumPtr>::~nn() = default;
+template<> nn<NS_PROJ::datum::DatumEnsemblePtr>::~nn() = default;
+template<> nn<NS_PROJ::datum::PrimeMeridianPtr>::~nn() = default;
+template<> nn<NS_PROJ::datum::EllipsoidPtr>::~nn() = default;
+template<> nn<NS_PROJ::datum::GeodeticReferenceFramePtr>::~nn() = default;
+template<> nn<NS_PROJ::datum::DynamicGeodeticReferenceFramePtr>::~nn() = default;
+template<> nn<NS_PROJ::datum::VerticalReferenceFramePtr>::~nn() = default;
+template<> nn<NS_PROJ::datum::DynamicVerticalReferenceFramePtr>::~nn() = default;
+template<> nn<NS_PROJ::datum::EngineeringDatumPtr>::~nn() = default;
+template<> nn<NS_PROJ::datum::TemporalDatumPtr>::~nn() = default;
+template<> nn<NS_PROJ::datum::ParametricDatumPtr>::~nn() = default;
+}}
+#endif
+
+NS_PROJ_START
+namespace datum {
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static util::PropertyMap createMapNameEPSGCode(const char *name, int code) {
+    return util::PropertyMap()
+        .set(common::IdentifiedObject::NAME_KEY, name)
+        .set(metadata::Identifier::CODESPACE_KEY, metadata::Identifier::EPSG)
+        .set(metadata::Identifier::CODE_KEY, code);
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct Datum::Private {
+    util::optional<std::string> anchorDefinition{};
+    util::optional<common::DateTime> publicationDate{};
+    common::IdentifiedObjectPtr conventionalRS{};
+
+    // cppcheck-suppress functionStatic
+    void exportAnchorDefinition(io::WKTFormatter *formatter) const;
+};
+
+// ---------------------------------------------------------------------------
+
+void Datum::Private::exportAnchorDefinition(io::WKTFormatter *formatter) const {
+    if (anchorDefinition) {
+        formatter->startNode(io::WKTConstants::ANCHOR, false);
+        formatter->addQuotedString(*anchorDefinition);
+        formatter->endNode();
+    }
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+Datum::Datum() : d(internal::make_unique<Private>()) {}
+
+// ---------------------------------------------------------------------------
+
+#ifdef notdef
+Datum::Datum(const Datum &other)
+    : ObjectUsage(other), d(internal::make_unique<Private>(*other.d)) {}
+#endif
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+Datum::~Datum() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the anchor definition.
+ *
+ * A description - possibly including coordinates of an identified point or
+ * points - of the relationship used to anchor a coordinate system to the
+ * Earth or alternate object.
+ * <ul>
+ * <li>For modern geodetic reference frames the anchor may be a set of station
+ * coordinates; if the reference frame is dynamic it will also include
+ * coordinate velocities. For a traditional geodetic datum, this anchor may be
+ * a point known as the fundamental point, which is traditionally the point
+ * where the relationship between geoid and ellipsoid is defined, together
+ * with a direction from that point.</li>
+ * <li>For a vertical reference frame the anchor may be the zero level at one
+ * or more defined locations or a conventionally defined surface.</li>
+ * <li>For an engineering datum, the anchor may be an identified physical point
+ * with the orientation defined relative to the object.</li>
+ * </ul>
+ *
+ * @return the anchor definition, or empty.
+ */
+const util::optional<std::string> &Datum::anchorDefinition() const {
+    return d->anchorDefinition;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the date on which the datum definition was published.
+ *
+ * \note Departure from \ref ISO_19111_2018 : we return a DateTime instead of
+ * a Citation::Date.
+ *
+ * @return the publication date, or empty.
+ */
+const util::optional<common::DateTime> &Datum::publicationDate() const {
+    return d->publicationDate;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the conventional reference system.
+ *
+ * This is the name, identifier, alias and remarks for the terrestrial
+ * reference system or vertical reference system realized by this reference
+ * frame, for example "ITRS" for ITRF88 through ITRF2008 and ITRF2014, or
+ * "EVRS" for EVRF2000 and EVRF2007.
+ *
+ * @return the conventional reference system, or nullptr.
+ */
+const common::IdentifiedObjectPtr &Datum::conventionalRS() const {
+    return d->conventionalRS;
+}
+
+// ---------------------------------------------------------------------------
+
+void Datum::setAnchor(const util::optional<std::string> &anchor) {
+    d->anchorDefinition = anchor;
+}
+
+// ---------------------------------------------------------------------------
+
+bool Datum::__isEquivalentTo(const util::IComparable *other,
+                             util::IComparable::Criterion criterion) const {
+    auto otherDatum = dynamic_cast<const Datum *>(other);
+    if (otherDatum == nullptr ||
+        !ObjectUsage::_isEquivalentTo(other, criterion)) {
+        return false;
+    }
+    if (criterion == util::IComparable::Criterion::STRICT) {
+        if ((anchorDefinition().has_value() ^
+             otherDatum->anchorDefinition().has_value())) {
+            return false;
+        }
+        if (anchorDefinition().has_value() &&
+            otherDatum->anchorDefinition().has_value() &&
+            *anchorDefinition() != *otherDatum->anchorDefinition()) {
+            return false;
+        }
+
+        if ((publicationDate().has_value() ^
+             otherDatum->publicationDate().has_value())) {
+            return false;
+        }
+        if (publicationDate().has_value() &&
+            otherDatum->publicationDate().has_value() &&
+            publicationDate()->toString() !=
+                otherDatum->publicationDate()->toString()) {
+            return false;
+        }
+
+        if (((conventionalRS() != nullptr) ^
+             (otherDatum->conventionalRS() != nullptr))) {
+            return false;
+        }
+        if (conventionalRS() && otherDatum->conventionalRS() &&
+            conventionalRS()->_isEquivalentTo(
+                otherDatum->conventionalRS().get(), criterion)) {
+            return false;
+        }
+    }
+    return true;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct PrimeMeridian::Private {
+    common::Angle longitude_{};
+
+    explicit Private(const common::Angle &longitude) : longitude_(longitude) {}
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+PrimeMeridian::PrimeMeridian(const common::Angle &longitudeIn)
+    : d(internal::make_unique<Private>(longitudeIn)) {}
+
+// ---------------------------------------------------------------------------
+
+#ifdef notdef
+PrimeMeridian::PrimeMeridian(const PrimeMeridian &other)
+    : common::IdentifiedObject(other),
+      d(internal::make_unique<Private>(*other.d)) {}
+#endif
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+PrimeMeridian::~PrimeMeridian() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the longitude of the prime meridian.
+ *
+ * It is measured from the internationally-recognised reference meridian
+ * ('Greenwich meridian'), positive eastward.
+ * The default value is 0 degrees.
+ *
+ * @return the longitude of the prime meridian.
+ */
+const common::Angle &PrimeMeridian::longitude() PROJ_CONST_DEFN {
+    return d->longitude_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a PrimeMeridian.
+ *
+ * @param properties See \ref general_properties.
+ * At minimum the name should be defined.
+ * @param longitudeIn the longitude of the prime meridian.
+ * @return new PrimeMeridian.
+ */
+PrimeMeridianNNPtr PrimeMeridian::create(const util::PropertyMap &properties,
+                                         const common::Angle &longitudeIn) {
+    auto pm(PrimeMeridian::nn_make_shared<PrimeMeridian>(longitudeIn));
+    pm->setProperties(properties);
+    return pm;
+}
+
+// ---------------------------------------------------------------------------
+
+const PrimeMeridianNNPtr PrimeMeridian::createGREENWICH() {
+    return create(createMapNameEPSGCode("Greenwich", 8901), common::Angle(0));
+}
+
+// ---------------------------------------------------------------------------
+
+const PrimeMeridianNNPtr PrimeMeridian::createREFERENCE_MERIDIAN() {
+    return create(util::PropertyMap().set(IdentifiedObject::NAME_KEY,
+                                          "Reference meridian"),
+                  common::Angle(0));
+}
+
+// ---------------------------------------------------------------------------
+
+const PrimeMeridianNNPtr PrimeMeridian::createPARIS() {
+    return create(createMapNameEPSGCode("Paris", 8903),
+                  common::Angle(2.5969213, common::UnitOfMeasure::GRAD));
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void PrimeMeridian::_exportToWKT(
+    io::WKTFormatter *formatter) const // throw(FormattingException)
+{
+    const bool isWKT2 = formatter->version() == io::WKTFormatter::Version::WKT2;
+    std::string l_name =
+        name()->description().has_value() ? nameStr() : "Greenwich";
+    if (!(isWKT2 && formatter->primeMeridianOmittedIfGreenwich() &&
+          l_name == "Greenwich")) {
+        formatter->startNode(io::WKTConstants::PRIMEM, !identifiers().empty());
+        formatter->addQuotedString(l_name);
+        const auto &l_long = longitude();
+        if (formatter->primeMeridianInDegree()) {
+            formatter->add(l_long.convertToUnit(common::UnitOfMeasure::DEGREE));
+        } else {
+            formatter->add(l_long.value());
+        }
+        const auto &unit = l_long.unit();
+        if (isWKT2) {
+            if (!(formatter
+                      ->primeMeridianOrParameterUnitOmittedIfSameAsAxis() &&
+                  unit == *(formatter->axisAngularUnit()))) {
+                unit._exportToWKT(formatter, io::WKTConstants::ANGLEUNIT);
+            }
+        } else if (!formatter->primeMeridianInDegree()) {
+            unit._exportToWKT(formatter);
+        }
+        if (formatter->outputId()) {
+            formatID(formatter);
+        }
+        formatter->endNode();
+    }
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+std::string
+PrimeMeridian::getPROJStringWellKnownName(const common::Angle &angle) {
+    const double valRad = angle.getSIValue();
+    std::string projPMName;
+    projCtx ctxt = pj_ctx_alloc();
+    auto proj_pm = proj_list_prime_meridians();
+    for (int i = 0; proj_pm[i].id != nullptr; ++i) {
+        double valRefRad = dmstor_ctx(ctxt, proj_pm[i].defn, nullptr);
+        if (::fabs(valRad - valRefRad) < 1e-10) {
+            projPMName = proj_pm[i].id;
+            break;
+        }
+    }
+    pj_ctx_free(ctxt);
+    return projPMName;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void PrimeMeridian::_exportToPROJString(
+    io::PROJStringFormatter *formatter) const // throw(FormattingException)
+{
+    if (longitude().getSIValue() != 0) {
+        std::string projPMName(getPROJStringWellKnownName(longitude()));
+        if (!projPMName.empty()) {
+            formatter->addParam("pm", projPMName);
+        } else {
+            const double valDeg =
+                longitude().convertToUnit(common::UnitOfMeasure::DEGREE);
+            formatter->addParam("pm", valDeg);
+        }
+    }
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+bool PrimeMeridian::_isEquivalentTo(
+    const util::IComparable *other,
+    util::IComparable::Criterion criterion) const {
+    auto otherPM = dynamic_cast<const PrimeMeridian *>(other);
+    if (otherPM == nullptr ||
+        !IdentifiedObject::_isEquivalentTo(other, criterion)) {
+        return false;
+    }
+    // In MapInfo, the Paris prime meridian is returned as 2.3372291666667
+    // instead of the official value of 2.33722917, which is a relative
+    // error in the 1e-9 range.
+    return longitude()._isEquivalentTo(otherPM->longitude(), criterion, 1e-8);
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct Ellipsoid::Private {
+    common::Length semiMajorAxis_{};
+    util::optional<common::Scale> inverseFlattening_{};
+    util::optional<common::Length> semiMinorAxis_{};
+    util::optional<common::Length> semiMedianAxis_{};
+    std::string celestialBody_{};
+
+    explicit Private(const common::Length &radius,
+                     const std::string &celestialBody)
+        : semiMajorAxis_(radius), celestialBody_(celestialBody) {}
+
+    Private(const common::Length &semiMajorAxisIn,
+            const common::Scale &invFlattening,
+            const std::string &celestialBody)
+        : semiMajorAxis_(semiMajorAxisIn), inverseFlattening_(invFlattening),
+          celestialBody_(celestialBody) {}
+
+    Private(const common::Length &semiMajorAxisIn,
+            const common::Length &semiMinorAxisIn,
+            const std::string &celestialBody)
+        : semiMajorAxis_(semiMajorAxisIn), semiMinorAxis_(semiMinorAxisIn),
+          celestialBody_(celestialBody) {}
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+Ellipsoid::Ellipsoid(const common::Length &radius,
+                     const std::string &celestialBodyIn)
+    : d(internal::make_unique<Private>(radius, celestialBodyIn)) {}
+
+// ---------------------------------------------------------------------------
+
+Ellipsoid::Ellipsoid(const common::Length &semiMajorAxisIn,
+                     const common::Scale &invFlattening,
+                     const std::string &celestialBodyIn)
+    : d(internal::make_unique<Private>(semiMajorAxisIn, invFlattening,
+                                       celestialBodyIn)) {}
+
+// ---------------------------------------------------------------------------
+
+Ellipsoid::Ellipsoid(const common::Length &semiMajorAxisIn,
+                     const common::Length &semiMinorAxisIn,
+                     const std::string &celestialBodyIn)
+    : d(internal::make_unique<Private>(semiMajorAxisIn, semiMinorAxisIn,
+                                       celestialBodyIn)) {}
+
+// ---------------------------------------------------------------------------
+
+#ifdef notdef
+Ellipsoid::Ellipsoid(const Ellipsoid &other)
+    : common::IdentifiedObject(other),
+      d(internal::make_unique<Private>(*other.d)) {}
+#endif
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+Ellipsoid::~Ellipsoid() = default;
+
+Ellipsoid::Ellipsoid(const Ellipsoid &other)
+    : IdentifiedObject(other), d(internal::make_unique<Private>(*(other.d))) {}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the length of the semi-major axis of the ellipsoid.
+ *
+ * @return the semi-major axis.
+ */
+const common::Length &Ellipsoid::semiMajorAxis() PROJ_CONST_DEFN {
+    return d->semiMajorAxis_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the inverse flattening value of the ellipsoid, if the
+ * ellipsoid
+ * has been defined with this value.
+ *
+ * @see computeInverseFlattening() that will always return a valid value of the
+ * inverse flattening, whether the ellipsoid has been defined through inverse
+ * flattening or semi-minor axis.
+ *
+ * @return the inverse flattening value of the ellipsoid, or empty.
+ */
+const util::optional<common::Scale> &
+Ellipsoid::inverseFlattening() PROJ_CONST_DEFN {
+    return d->inverseFlattening_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the length of the semi-minor axis of the ellipsoid, if the
+ * ellipsoid
+ * has been defined with this value.
+ *
+ * @see computeSemiMinorAxis() that will always return a valid value of the
+ * inverse flattening, whether the ellipsoid has been defined through inverse
+ * flattening or semi-minor axis.
+ *
+ * @return the semi-minor axis of the ellipsoid, or empty.
+ */
+const util::optional<common::Length> &
+Ellipsoid::semiMinorAxis() PROJ_CONST_DEFN {
+    return d->semiMinorAxis_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return whether the ellipsoid is spherical.
+ *
+ * That is to say is semiMajorAxis() == computeSemiMinorAxis().
+ *
+ * A sphere is completely defined by the semi-major axis, which is the radius
+ * of the sphere.
+ *
+ * @return true if the ellipsoid is spherical.
+ */
+bool Ellipsoid::isSphere() PROJ_CONST_DEFN {
+    if (d->inverseFlattening_.has_value()) {
+        return d->inverseFlattening_->value() == 0;
+    }
+
+    if (semiMinorAxis().has_value()) {
+        return semiMajorAxis() == *semiMinorAxis();
+    }
+
+    return true;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the length of the semi-median axis of a triaxial ellipsoid
+ *
+ * This parameter is not required for a biaxial ellipsoid.
+ *
+ * @return the semi-median axis of the ellipsoid, or empty.
+ */
+const util::optional<common::Length> &
+Ellipsoid::semiMedianAxis() PROJ_CONST_DEFN {
+    return d->semiMedianAxis_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return or compute the inverse flattening value of the ellipsoid.
+ *
+ * If computed, the inverse flattening is the result of a / (a - b),
+ * where a is the semi-major axis and b the semi-minor axis.
+ *
+ * @return the inverse flattening value of the ellipsoid, or 0 for a sphere.
+ */
+double Ellipsoid::computedInverseFlattening() PROJ_CONST_DEFN {
+    if (d->inverseFlattening_.has_value()) {
+        return d->inverseFlattening_->getSIValue();
+    }
+
+    if (d->semiMinorAxis_.has_value()) {
+        const double a = d->semiMajorAxis_.getSIValue();
+        const double b = d->semiMinorAxis_->getSIValue();
+        return (a == b) ? 0.0 : a / (a - b);
+    }
+
+    return 0.0;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the squared eccentricity of the ellipsoid.
+ *
+ * @return the squared eccentricity, or a negative value if invalid.
+ */
+double Ellipsoid::squaredEccentricity() PROJ_CONST_DEFN {
+    const double rf = computedInverseFlattening();
+    const double f = rf != 0.0 ? 1. / rf : 0.0;
+    const double e2 = f * (2 - f);
+    return e2;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return or compute the length of the semi-minor axis of the ellipsoid.
+ *
+ * If computed, the semi-minor axis is the result of a * (1 - 1 / rf)
+ * where a is the semi-major axis and rf the reverse/inverse flattening.
+
+ * @return the semi-minor axis of the ellipsoid.
+ */
+common::Length Ellipsoid::computeSemiMinorAxis() const {
+    if (d->semiMinorAxis_.has_value()) {
+        return *d->semiMinorAxis_;
+    }
+
+    if (inverseFlattening().has_value()) {
+        return common::Length(
+            (1.0 - 1.0 / d->inverseFlattening_->getSIValue()) *
+                d->semiMajorAxis_.value(),
+            d->semiMajorAxis_.unit());
+    }
+
+    return d->semiMajorAxis_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the name of the celestial body on which the ellipsoid refers
+ * to.
+ */
+const std::string &Ellipsoid::celestialBody() PROJ_CONST_DEFN {
+    return d->celestialBody_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a Ellipsoid as a sphere.
+ *
+ * @param properties See \ref general_properties.
+ * At minimum the name should be defined.
+ * @param radius the sphere radius (semi-major axis).
+ * @param celestialBody Name of the celestial body on which the ellipsoid refers
+ * to.
+ * @return new Ellipsoid.
+ */
+EllipsoidNNPtr Ellipsoid::createSphere(const util::PropertyMap &properties,
+                                       const common::Length &radius,
+                                       const std::string &celestialBody) {
+    auto ellipsoid(Ellipsoid::nn_make_shared<Ellipsoid>(radius, celestialBody));
+    ellipsoid->setProperties(properties);
+    return ellipsoid;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a Ellipsoid from its inverse/reverse flattening.
+ *
+ * @param properties See \ref general_properties.
+ * At minimum the name should be defined.
+ * @param semiMajorAxisIn the semi-major axis.
+ * @param invFlattening the inverse/reverse flattening.
+ * @param celestialBody Name of the celestial body on which the ellipsoid refers
+ * to.
+ * @return new Ellipsoid.
+ */
+EllipsoidNNPtr Ellipsoid::createFlattenedSphere(
+    const util::PropertyMap &properties, const common::Length &semiMajorAxisIn,
+    const common::Scale &invFlattening, const std::string &celestialBody) {
+    auto ellipsoid(Ellipsoid::nn_make_shared<Ellipsoid>(
+        semiMajorAxisIn, invFlattening, celestialBody));
+    ellipsoid->setProperties(properties);
+    return ellipsoid;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a Ellipsoid from the value of its two semi axis.
+ *
+ * @param properties See \ref general_properties.
+ * At minimum the name should be defined.
+ * @param semiMajorAxisIn the semi-major axis.
+ * @param semiMinorAxisIn the semi-minor axis.
+ * @param celestialBody Name of the celestial body on which the ellipsoid refers
+ * to.
+ * @return new Ellipsoid.
+ */
+EllipsoidNNPtr Ellipsoid::createTwoAxis(const util::PropertyMap &properties,
+                                        const common::Length &semiMajorAxisIn,
+                                        const common::Length &semiMinorAxisIn,
+                                        const std::string &celestialBody) {
+    auto ellipsoid(Ellipsoid::nn_make_shared<Ellipsoid>(
+        semiMajorAxisIn, semiMinorAxisIn, celestialBody));
+    ellipsoid->setProperties(properties);
+    return ellipsoid;
+}
+
+// ---------------------------------------------------------------------------
+
+const EllipsoidNNPtr Ellipsoid::createCLARKE_1866() {
+    return createTwoAxis(createMapNameEPSGCode("Clarke 1866", 7008),
+                         common::Length(6378206.4), common::Length(6356583.8));
+}
+
+// ---------------------------------------------------------------------------
+
+const EllipsoidNNPtr Ellipsoid::createWGS84() {
+    return createFlattenedSphere(createMapNameEPSGCode("WGS 84", 7030),
+                                 common::Length(6378137),
+                                 common::Scale(298.257223563));
+}
+
+// ---------------------------------------------------------------------------
+
+const EllipsoidNNPtr Ellipsoid::createGRS1980() {
+    return createFlattenedSphere(createMapNameEPSGCode("GRS 1980", 7019),
+                                 common::Length(6378137),
+                                 common::Scale(298.257222101));
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void Ellipsoid::_exportToWKT(
+    io::WKTFormatter *formatter) const // throw(FormattingException)
+{
+    const bool isWKT2 = formatter->version() == io::WKTFormatter::Version::WKT2;
+    formatter->startNode(isWKT2 ? io::WKTConstants::ELLIPSOID
+                                : io::WKTConstants::SPHEROID,
+                         !identifiers().empty());
+    {
+        auto l_name = nameStr();
+        if (l_name.empty()) {
+            formatter->addQuotedString("unnamed");
+        } else {
+            if (formatter->useESRIDialect()) {
+                if (l_name == "WGS 84") {
+                    l_name = "WGS_1984";
+                } else {
+                    bool aliasFound = false;
+                    const auto &dbContext = formatter->databaseContext();
+                    if (dbContext) {
+                        auto l_alias = dbContext->getAliasFromOfficialName(
+                            l_name, "ellipsoid", "ESRI");
+                        if (!l_alias.empty()) {
+                            l_name = l_alias;
+                            aliasFound = true;
+                        }
+                    }
+                    if (!aliasFound) {
+                        l_name = io::WKTFormatter::morphNameToESRI(l_name);
+                    }
+                }
+            }
+            formatter->addQuotedString(l_name);
+        }
+        const auto &semiMajor = semiMajorAxis();
+        if (isWKT2) {
+            formatter->add(semiMajor.value());
+        } else {
+            formatter->add(semiMajor.getSIValue());
+        }
+        formatter->add(computedInverseFlattening());
+        const auto &unit = semiMajor.unit();
+        if (isWKT2 &&
+            !(formatter->ellipsoidUnitOmittedIfMetre() &&
+              unit == common::UnitOfMeasure::METRE)) {
+            unit._exportToWKT(formatter, io::WKTConstants::LENGTHUNIT);
+        }
+        if (formatter->outputId()) {
+            formatID(formatter);
+        }
+    }
+    formatter->endNode();
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+bool Ellipsoid::lookForProjWellKnownEllps(std::string &projEllpsName,
+                                          std::string &ellpsName) const {
+    const double a = semiMajorAxis().getSIValue();
+    const double b = computeSemiMinorAxis().getSIValue();
+    const double rf = computedInverseFlattening();
+    auto proj_ellps = proj_list_ellps();
+    for (int i = 0; proj_ellps[i].id != nullptr; i++) {
+        assert(strncmp(proj_ellps[i].major, "a=", 2) == 0);
+        const double a_iter = c_locale_stod(proj_ellps[i].major + 2);
+        if (::fabs(a - a_iter) < 1e-10 * a_iter) {
+            if (strncmp(proj_ellps[i].ell, "b=", 2) == 0) {
+                const double b_iter = c_locale_stod(proj_ellps[i].ell + 2);
+                if (::fabs(b - b_iter) < 1e-10 * b_iter) {
+                    projEllpsName = proj_ellps[i].id;
+                    ellpsName = proj_ellps[i].name;
+                    if (ellpsName.find("GRS 1980") == 0) {
+                        ellpsName = "GRS 1980";
+                    }
+                    return true;
+                }
+            } else {
+                assert(strncmp(proj_ellps[i].ell, "rf=", 3) == 0);
+                const double rf_iter = c_locale_stod(proj_ellps[i].ell + 3);
+                if (::fabs(rf - rf_iter) < 1e-10 * rf_iter) {
+                    projEllpsName = proj_ellps[i].id;
+                    ellpsName = proj_ellps[i].name;
+                    if (ellpsName.find("GRS 1980") == 0) {
+                        ellpsName = "GRS 1980";
+                    }
+                    return true;
+                }
+            }
+        }
+    }
+    return false;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void Ellipsoid::_exportToPROJString(
+    io::PROJStringFormatter *formatter) const // throw(FormattingException)
+{
+    const double a = semiMajorAxis().getSIValue();
+
+    std::string projEllpsName;
+    std::string ellpsName;
+    if (lookForProjWellKnownEllps(projEllpsName, ellpsName)) {
+        formatter->addParam("ellps", projEllpsName);
+        return;
+    }
+
+    if (isSphere()) {
+        formatter->addParam("R", a);
+    } else {
+        formatter->addParam("a", a);
+        if (inverseFlattening().has_value()) {
+            const double rf = computedInverseFlattening();
+            formatter->addParam("rf", rf);
+        } else {
+            const double b = computeSemiMinorAxis().getSIValue();
+            formatter->addParam("b", b);
+        }
+    }
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return a Ellipsoid object where some parameters are better
+ * identified.
+ *
+ * @return a new Ellipsoid.
+ */
+EllipsoidNNPtr Ellipsoid::identify() const {
+    auto newEllipsoid = Ellipsoid::nn_make_shared<Ellipsoid>(*this);
+    newEllipsoid->assignSelf(
+        util::nn_static_pointer_cast<util::BaseObject>(newEllipsoid));
+
+    if (name()->description()->empty() || nameStr() == "unknown") {
+        std::string projEllpsName;
+        std::string ellpsName;
+        if (lookForProjWellKnownEllps(projEllpsName, ellpsName)) {
+            newEllipsoid->setProperties(
+                util::PropertyMap().set(IdentifiedObject::NAME_KEY, ellpsName));
+        }
+    }
+
+    return newEllipsoid;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+bool Ellipsoid::_isEquivalentTo(const util::IComparable *other,
+                                util::IComparable::Criterion criterion) const {
+    auto otherEllipsoid = dynamic_cast<const Ellipsoid *>(other);
+    if (otherEllipsoid == nullptr ||
+        (criterion == util::IComparable::Criterion::STRICT &&
+         !IdentifiedObject::_isEquivalentTo(other, criterion))) {
+        return false;
+    }
+
+    // PROJ "clrk80" name is "Clarke 1880 mod." and GDAL tends to
+    // export to it a number of Clarke 1880 variants, so be lax
+    if (criterion != util::IComparable::Criterion::STRICT &&
+        (nameStr() == "Clarke 1880 mod." ||
+         otherEllipsoid->nameStr() == "Clarke 1880 mod.")) {
+        return std::fabs(semiMajorAxis().getSIValue() -
+                         otherEllipsoid->semiMajorAxis().getSIValue()) <
+                   1e-8 * semiMajorAxis().getSIValue() &&
+               std::fabs(computedInverseFlattening() -
+                         otherEllipsoid->computedInverseFlattening()) <
+                   1e-5 * computedInverseFlattening();
+    }
+
+    if (!semiMajorAxis()._isEquivalentTo(otherEllipsoid->semiMajorAxis(),
+                                         criterion)) {
+        return false;
+    }
+
+    const auto &l_semiMinorAxis = semiMinorAxis();
+    const auto &l_other_semiMinorAxis = otherEllipsoid->semiMinorAxis();
+    if (l_semiMinorAxis.has_value() && l_other_semiMinorAxis.has_value()) {
+        if (!l_semiMinorAxis->_isEquivalentTo(*l_other_semiMinorAxis,
+                                              criterion)) {
+            return false;
+        }
+    }
+
+    const auto &l_inverseFlattening = inverseFlattening();
+    const auto &l_other_sinverseFlattening =
+        otherEllipsoid->inverseFlattening();
+    if (l_inverseFlattening.has_value() &&
+        l_other_sinverseFlattening.has_value()) {
+        if (!l_inverseFlattening->_isEquivalentTo(*l_other_sinverseFlattening,
+                                                  criterion)) {
+            return false;
+        }
+    }
+
+    if (criterion == util::IComparable::Criterion::STRICT) {
+        if ((l_semiMinorAxis.has_value() ^ l_other_semiMinorAxis.has_value())) {
+            return false;
+        }
+
+        if ((l_inverseFlattening.has_value() ^
+             l_other_sinverseFlattening.has_value())) {
+            return false;
+        }
+
+    } else {
+        if (!otherEllipsoid->computeSemiMinorAxis()._isEquivalentTo(
+                otherEllipsoid->computeSemiMinorAxis(), criterion)) {
+            return false;
+        }
+    }
+
+    const auto &l_semiMedianAxis = semiMedianAxis();
+    const auto &l_other_semiMedianAxis = otherEllipsoid->semiMedianAxis();
+    if ((l_semiMedianAxis.has_value() ^ l_other_semiMedianAxis.has_value())) {
+        return false;
+    }
+    if (l_semiMedianAxis.has_value() && l_other_semiMedianAxis.has_value()) {
+        if (!l_semiMedianAxis->_isEquivalentTo(*l_other_semiMedianAxis,
+                                               criterion)) {
+            return false;
+        }
+    }
+    return true;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+std::string Ellipsoid::guessBodyName(const io::DatabaseContextPtr &dbContext,
+                                     double a) {
+    constexpr double relError = 0.005;
+    constexpr double earthMeanRadius = 6375000.0;
+    if (std::fabs(a - earthMeanRadius) < relError * earthMeanRadius) {
+        return Ellipsoid::EARTH;
+    }
+    if (dbContext) {
+        try {
+            auto factory = io::AuthorityFactory::create(NN_NO_CHECK(dbContext),
+                                                        std::string());
+            return factory->identifyBodyFromSemiMajorAxis(a, relError);
+        } catch (const std::exception &) {
+        }
+    }
+    return "Non-Earth body";
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct GeodeticReferenceFrame::Private {
+    PrimeMeridianNNPtr primeMeridian_;
+    EllipsoidNNPtr ellipsoid_;
+
+    Private(const EllipsoidNNPtr &ellipsoidIn,
+            const PrimeMeridianNNPtr &primeMeridianIn)
+        : primeMeridian_(primeMeridianIn), ellipsoid_(ellipsoidIn) {}
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+GeodeticReferenceFrame::GeodeticReferenceFrame(
+    const EllipsoidNNPtr &ellipsoidIn,
+    const PrimeMeridianNNPtr &primeMeridianIn)
+    : d(internal::make_unique<Private>(ellipsoidIn, primeMeridianIn)) {}
+
+// ---------------------------------------------------------------------------
+
+#ifdef notdef
+GeodeticReferenceFrame::GeodeticReferenceFrame(
+    const GeodeticReferenceFrame &other)
+    : Datum(other), d(internal::make_unique<Private>(*other.d)) {}
+#endif
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+GeodeticReferenceFrame::~GeodeticReferenceFrame() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the PrimeMeridian associated with a GeodeticReferenceFrame.
+ *
+ * @return the PrimeMeridian.
+ */
+const PrimeMeridianNNPtr &
+GeodeticReferenceFrame::primeMeridian() PROJ_CONST_DEFN {
+    return d->primeMeridian_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the Ellipsoid associated with a GeodeticReferenceFrame.
+ *
+ * \note The \ref ISO_19111_2018 modelling allows (but discourages) a
+ * GeodeticReferenceFrame
+ * to not be associated with a Ellipsoid in the case where it is used by a
+ * geocentric crs::GeodeticCRS. We have made the choice of making the ellipsoid
+ * specification compulsory.
+ *
+ * @return the Ellipsoid.
+ */
+const EllipsoidNNPtr &GeodeticReferenceFrame::ellipsoid() PROJ_CONST_DEFN {
+    return d->ellipsoid_;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a GeodeticReferenceFrame
+ *
+ * @param properties See \ref general_properties.
+ * At minimum the name should be defined.
+ * @param ellipsoid the Ellipsoid.
+ * @param anchor the anchor definition, or empty.
+ * @param primeMeridian the PrimeMeridian.
+ * @return new GeodeticReferenceFrame.
+ */
+GeodeticReferenceFrameNNPtr
+GeodeticReferenceFrame::create(const util::PropertyMap &properties,
+                               const EllipsoidNNPtr &ellipsoid,
+                               const util::optional<std::string> &anchor,
+                               const PrimeMeridianNNPtr &primeMeridian) {
+    GeodeticReferenceFrameNNPtr grf(
+        GeodeticReferenceFrame::nn_make_shared<GeodeticReferenceFrame>(
+            ellipsoid, primeMeridian));
+    grf->setAnchor(anchor);
+    grf->setProperties(properties);
+    return grf;
+}
+
+// ---------------------------------------------------------------------------
+
+const GeodeticReferenceFrameNNPtr GeodeticReferenceFrame::createEPSG_6267() {
+    return create(createMapNameEPSGCode("North American Datum 1927", 6267),
+                  Ellipsoid::CLARKE_1866, util::optional<std::string>(),
+                  PrimeMeridian::GREENWICH);
+}
+
+// ---------------------------------------------------------------------------
+
+const GeodeticReferenceFrameNNPtr GeodeticReferenceFrame::createEPSG_6269() {
+    return create(createMapNameEPSGCode("North American Datum 1983", 6269),
+                  Ellipsoid::GRS1980, util::optional<std::string>(),
+                  PrimeMeridian::GREENWICH);
+}
+
+// ---------------------------------------------------------------------------
+
+const GeodeticReferenceFrameNNPtr GeodeticReferenceFrame::createEPSG_6326() {
+    return create(createMapNameEPSGCode("World Geodetic System 1984", 6326),
+                  Ellipsoid::WGS84, util::optional<std::string>(),
+                  PrimeMeridian::GREENWICH);
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void GeodeticReferenceFrame::_exportToWKT(
+    io::WKTFormatter *formatter) const // throw(FormattingException)
+{
+    const bool isWKT2 = formatter->version() == io::WKTFormatter::Version::WKT2;
+    formatter->startNode(io::WKTConstants::DATUM, !identifiers().empty());
+    auto l_name = nameStr();
+    if (l_name.empty()) {
+        l_name = "unnamed";
+    }
+    if (!isWKT2) {
+        if (formatter->useESRIDialect()) {
+            if (l_name == "World Geodetic System 1984") {
+                l_name = "D_WGS_1984";
+            } else {
+                bool aliasFound = false;
+                const auto &dbContext = formatter->databaseContext();
+                if (dbContext) {
+                    auto l_alias = dbContext->getAliasFromOfficialName(
+                        l_name, "geodetic_datum", "ESRI");
+                    size_t pos;
+                    if (!l_alias.empty()) {
+                        l_name = l_alias;
+                        aliasFound = true;
+                    } else if ((pos = l_name.find(" (")) != std::string::npos) {
+                        l_alias = dbContext->getAliasFromOfficialName(
+                            l_name.substr(0, pos), "geodetic_datum", "ESRI");
+                        if (!l_alias.empty()) {
+                            l_name = l_alias;
+                            aliasFound = true;
+                        }
+                    }
+                }
+                if (!aliasFound) {
+                    l_name = io::WKTFormatter::morphNameToESRI(l_name);
+                    if (!starts_with(l_name, "D_")) {
+                        l_name = "D_" + l_name;
+                    }
+                }
+            }
+            // Replace spaces by underscore, except if it is a special MapInfo
+            // datum name
+        } else if (!starts_with(l_name, "MIF ")) {
+            l_name = io::WKTFormatter::morphNameToESRI(l_name);
+            if (l_name == "World_Geodetic_System_1984") {
+                l_name = "WGS_1984";
+            }
+        }
+    }
+    formatter->addQuotedString(l_name);
+
+    ellipsoid()->_exportToWKT(formatter);
+    if (isWKT2) {
+        Datum::getPrivate()->exportAnchorDefinition(formatter);
+    } else {
+        const auto &TOWGS84Params = formatter->getTOWGS84Parameters();
+        if (TOWGS84Params.size() == 7) {
+            formatter->startNode(io::WKTConstants::TOWGS84, false);
+            for (const auto &val : TOWGS84Params) {
+                formatter->add(val);
+            }
+            formatter->endNode();
+        }
+        std::string extension = formatter->getHDatumExtension();
+        if (!extension.empty()) {
+            formatter->startNode(io::WKTConstants::EXTENSION, false);
+            formatter->addQuotedString("PROJ4_GRIDS");
+            formatter->addQuotedString(extension);
+            formatter->endNode();
+        }
+    }
+    if (formatter->outputId()) {
+        formatID(formatter);
+    }
+    // the PRIMEM is exported as a child of the CRS
+    formatter->endNode();
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+bool GeodeticReferenceFrame::_isEquivalentTo(
+    const util::IComparable *other,
+    util::IComparable::Criterion criterion) const {
+    auto otherGRF = dynamic_cast<const GeodeticReferenceFrame *>(other);
+    if (otherGRF == nullptr || !Datum::_isEquivalentTo(other, criterion)) {
+        return false;
+    }
+    return primeMeridian()->_isEquivalentTo(otherGRF->primeMeridian().get(),
+                                            criterion) &&
+           ellipsoid()->_isEquivalentTo(otherGRF->ellipsoid().get(), criterion);
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct DynamicGeodeticReferenceFrame::Private {
+    common::Measure frameReferenceEpoch{};
+    util::optional<std::string> deformationModelName{};
+
+    explicit Private(const common::Measure &frameReferenceEpochIn)
+        : frameReferenceEpoch(frameReferenceEpochIn) {}
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+DynamicGeodeticReferenceFrame::DynamicGeodeticReferenceFrame(
+    const EllipsoidNNPtr &ellipsoidIn,
+    const PrimeMeridianNNPtr &primeMeridianIn,
+    const common::Measure &frameReferenceEpochIn,
+    const util::optional<std::string> &deformationModelNameIn)
+    : GeodeticReferenceFrame(ellipsoidIn, primeMeridianIn),
+      d(internal::make_unique<Private>(frameReferenceEpochIn)) {
+    d->deformationModelName = deformationModelNameIn;
+}
+
+// ---------------------------------------------------------------------------
+
+#ifdef notdef
+DynamicGeodeticReferenceFrame::DynamicGeodeticReferenceFrame(
+    const DynamicGeodeticReferenceFrame &other)
+    : GeodeticReferenceFrame(other),
+      d(internal::make_unique<Private>(*other.d)) {}
+#endif
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+DynamicGeodeticReferenceFrame::~DynamicGeodeticReferenceFrame() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the epoch to which the coordinates of stations defining the
+ * dynamic geodetic reference frame are referenced.
+ *
+ * Usually given as a decimal year e.g. 2016.47.
+ *
+ * @return the frame reference epoch.
+ */
+const common::Measure &
+DynamicGeodeticReferenceFrame::frameReferenceEpoch() const {
+    return d->frameReferenceEpoch;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the name of the deformation model.
+ *
+ * @note This is an extension to the \ref ISO_19111_2018 modeling, to
+ * hold the content of the DYNAMIC.MODEL WKT2 node.
+ *
+ * @return the name of the deformation model.
+ */
+const util::optional<std::string> &
+DynamicGeodeticReferenceFrame::deformationModelName() const {
+    return d->deformationModelName;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+bool DynamicGeodeticReferenceFrame::_isEquivalentTo(
+    const util::IComparable *other,
+    util::IComparable::Criterion criterion) const {
+    auto otherDGRF = dynamic_cast<const DynamicGeodeticReferenceFrame *>(other);
+    if (otherDGRF == nullptr ||
+        !GeodeticReferenceFrame::_isEquivalentTo(other, criterion)) {
+        return false;
+    }
+    return frameReferenceEpoch()._isEquivalentTo(
+               otherDGRF->frameReferenceEpoch(), criterion) &&
+           metadata::Identifier::isEquivalentName(
+               deformationModelName()->c_str(),
+               otherDGRF->deformationModelName()->c_str());
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void DynamicGeodeticReferenceFrame::_exportToWKT(
+    io::WKTFormatter *formatter) const // throw(FormattingException)
+{
+    const bool isWKT2 = formatter->version() == io::WKTFormatter::Version::WKT2;
+    if (isWKT2 && formatter->use2018Keywords()) {
+        formatter->startNode(io::WKTConstants::DYNAMIC, false);
+        formatter->startNode(io::WKTConstants::FRAMEEPOCH, false);
+        formatter->add(
+            frameReferenceEpoch().convertToUnit(common::UnitOfMeasure::YEAR));
+        formatter->endNode();
+        if (deformationModelName().has_value() &&
+            !deformationModelName()->empty()) {
+            formatter->startNode(io::WKTConstants::MODEL, false);
+            formatter->addQuotedString(*deformationModelName());
+            formatter->endNode();
+        }
+        formatter->endNode();
+    }
+    GeodeticReferenceFrame::_exportToWKT(formatter);
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a DyanmicGeodeticReferenceFrame
+ *
+ * @param properties See \ref general_properties.
+ * At minimum the name should be defined.
+ * @param ellipsoid the Ellipsoid.
+ * @param anchor the anchor definition, or empty.
+ * @param primeMeridian the PrimeMeridian.
+ * @param frameReferenceEpochIn the frame reference epoch.
+ * @param deformationModelNameIn deformation model name, or empty
+ * @return new DyanmicGeodeticReferenceFrame.
+ */
+DynamicGeodeticReferenceFrameNNPtr DynamicGeodeticReferenceFrame::create(
+    const util::PropertyMap &properties, const EllipsoidNNPtr &ellipsoid,
+    const util::optional<std::string> &anchor,
+    const PrimeMeridianNNPtr &primeMeridian,
+    const common::Measure &frameReferenceEpochIn,
+    const util::optional<std::string> &deformationModelNameIn) {
+    DynamicGeodeticReferenceFrameNNPtr grf(
+        DynamicGeodeticReferenceFrame::nn_make_shared<
+            DynamicGeodeticReferenceFrame>(ellipsoid, primeMeridian,
+                                           frameReferenceEpochIn,
+                                           deformationModelNameIn));
+    grf->setAnchor(anchor);
+    grf->setProperties(properties);
+    return grf;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct DatumEnsemble::Private {
+    std::vector<DatumNNPtr> datums{};
+    metadata::PositionalAccuracyNNPtr positionalAccuracy;
+
+    Private(const std::vector<DatumNNPtr> &datumsIn,
+            const metadata::PositionalAccuracyNNPtr &accuracy)
+        : datums(datumsIn), positionalAccuracy(accuracy) {}
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+DatumEnsemble::DatumEnsemble(const std::vector<DatumNNPtr> &datumsIn,
+                             const metadata::PositionalAccuracyNNPtr &accuracy)
+    : d(internal::make_unique<Private>(datumsIn, accuracy)) {}
+
+// ---------------------------------------------------------------------------
+
+#ifdef notdef
+DatumEnsemble::DatumEnsemble(const DatumEnsemble &other)
+    : common::IdentifiedObject(other),
+      d(internal::make_unique<Private>(*other.d)) {}
+#endif
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+DatumEnsemble::~DatumEnsemble() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the set of datums which may be considered to be
+ * insignificantly different from each other.
+ *
+ * @return the set of datums of the DatumEnsemble.
+ */
+const std::vector<DatumNNPtr> &DatumEnsemble::datums() const {
+    return d->datums;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the inaccuracy introduced through use of this collection of
+ * datums.
+ *
+ * It is an indication of the differences in coordinate values at all points
+ * between the various realizations that have been grouped into this datum
+ * ensemble.
+ *
+ * @return the accuracy.
+ */
+const metadata::PositionalAccuracyNNPtr &
+DatumEnsemble::positionalAccuracy() const {
+    return d->positionalAccuracy;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void DatumEnsemble::_exportToWKT(
+    io::WKTFormatter *formatter) const // throw(FormattingException)
+{
+    const bool isWKT2 = formatter->version() == io::WKTFormatter::Version::WKT2;
+    if (!isWKT2 || !formatter->use2018Keywords()) {
+        throw io::FormattingException(
+            "DatumEnsemble can only be exported to WKT2:2018");
+    }
+
+    auto l_datums = datums();
+    assert(!l_datums.empty());
+
+    formatter->startNode(io::WKTConstants::ENSEMBLE, false);
+    const auto &l_name = nameStr();
+    if (!l_name.empty()) {
+        formatter->addQuotedString(l_name);
+    } else {
+        formatter->addQuotedString("unnamed");
+    }
+
+    for (const auto &datum : l_datums) {
+        formatter->startNode(io::WKTConstants::MEMBER,
+                             !datum->identifiers().empty());
+        const auto &l_datum_name = datum->nameStr();
+        if (!l_datum_name.empty()) {
+            formatter->addQuotedString(l_datum_name);
+        } else {
+            formatter->addQuotedString("unnamed");
+        }
+        if (formatter->outputId()) {
+            datum->formatID(formatter);
+        }
+        formatter->endNode();
+    }
+
+    auto grfFirst = std::dynamic_pointer_cast<GeodeticReferenceFrame>(
+        l_datums[0].as_nullable());
+    if (grfFirst) {
+        grfFirst->ellipsoid()->_exportToWKT(formatter);
+    }
+
+    formatter->startNode(io::WKTConstants::ENSEMBLEACCURACY, false);
+    formatter->add(positionalAccuracy()->value());
+    formatter->endNode();
+    formatter->endNode();
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a DatumEnsemble.
+ *
+ * @param properties See \ref general_properties.
+ * At minimum the name should be defined.
+ * @param datumsIn Array of at least 2 datums.
+ * @param accuracy Accuracy of the datum ensemble
+ * @return new DatumEnsemble.
+ * @throw util::Exception
+ */
+DatumEnsembleNNPtr DatumEnsemble::create(
+    const util::PropertyMap &properties,
+    const std::vector<DatumNNPtr> &datumsIn,
+    const metadata::PositionalAccuracyNNPtr &accuracy) // throw(Exception)
+{
+    if (datumsIn.size() < 2) {
+        throw util::Exception("ensemble should have at least 2 datums");
+    }
+    if (auto grfFirst =
+            dynamic_cast<const GeodeticReferenceFrame *>(datumsIn[0].get())) {
+        for (size_t i = 1; i < datumsIn.size(); i++) {
+            auto grf =
+                dynamic_cast<const GeodeticReferenceFrame *>(datumsIn[i].get());
+            if (!grf) {
+                throw util::Exception(
+                    "ensemble should have consistent datum types");
+            }
+            if (!grfFirst->ellipsoid()->_isEquivalentTo(
+                    grf->ellipsoid().get())) {
+                throw util::Exception(
+                    "ensemble should have datums with identical ellipsoid");
+            }
+            if (!grfFirst->primeMeridian()->_isEquivalentTo(
+                    grf->primeMeridian().get())) {
+                throw util::Exception(
+                    "ensemble should have datums with identical "
+                    "prime meridian");
+            }
+        }
+    } else if (dynamic_cast<VerticalReferenceFrame *>(datumsIn[0].get())) {
+        for (size_t i = 1; i < datumsIn.size(); i++) {
+            if (!dynamic_cast<VerticalReferenceFrame *>(datumsIn[i].get())) {
+                throw util::Exception(
+                    "ensemble should have consistent datum types");
+            }
+        }
+    }
+    auto ensemble(
+        DatumEnsemble::nn_make_shared<DatumEnsemble>(datumsIn, accuracy));
+    ensemble->setProperties(properties);
+    return ensemble;
+}
+
+// ---------------------------------------------------------------------------
+
+RealizationMethod::RealizationMethod(const std::string &nameIn)
+    : CodeList(nameIn) {}
+
+// ---------------------------------------------------------------------------
+
+RealizationMethod::RealizationMethod(const RealizationMethod &) = default;
+
+// ---------------------------------------------------------------------------
+
+RealizationMethod &RealizationMethod::
+operator=(const RealizationMethod &other) {
+    CodeList::operator=(other);
+    return *this;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct VerticalReferenceFrame::Private {
+    util::optional<RealizationMethod> realizationMethod_{};
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+VerticalReferenceFrame::VerticalReferenceFrame(
+    const util::optional<RealizationMethod> &realizationMethodIn)
+    : d(internal::make_unique<Private>()) {
+    if (!realizationMethodIn->toString().empty()) {
+        d->realizationMethod_ = *realizationMethodIn;
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+VerticalReferenceFrame::~VerticalReferenceFrame() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the method through which this vertical reference frame is
+ * realized.
+ *
+ * @return the realization method.
+ */
+const util::optional<RealizationMethod> &
+VerticalReferenceFrame::realizationMethod() const {
+    return d->realizationMethod_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a VerticalReferenceFrame
+ *
+ * @param properties See \ref general_properties.
+ * At minimum the name should be defined.
+ * @param anchor the anchor definition, or empty.
+ * @param realizationMethodIn the realization method, or empty.
+ * @return new VerticalReferenceFrame.
+ */
+VerticalReferenceFrameNNPtr VerticalReferenceFrame::create(
+    const util::PropertyMap &properties,
+    const util::optional<std::string> &anchor,
+    const util::optional<RealizationMethod> &realizationMethodIn) {
+    auto rf(VerticalReferenceFrame::nn_make_shared<VerticalReferenceFrame>(
+        realizationMethodIn));
+    rf->setAnchor(anchor);
+    rf->setProperties(properties);
+    return rf;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void VerticalReferenceFrame::_exportToWKT(
+    io::WKTFormatter *formatter) const // throw(FormattingException)
+{
+    const bool isWKT2 = formatter->version() == io::WKTFormatter::Version::WKT2;
+    formatter->startNode(isWKT2 ? io::WKTConstants::VDATUM
+                                : io::WKTConstants::VERT_DATUM,
+                         !identifiers().empty());
+    const auto &l_name = nameStr();
+    if (!l_name.empty()) {
+        formatter->addQuotedString(l_name);
+    } else {
+        formatter->addQuotedString("unnamed");
+    }
+    if (isWKT2) {
+        Datum::getPrivate()->exportAnchorDefinition(formatter);
+    } else {
+        formatter->add(2005); // CS_VD_GeoidModelDerived from OGC 01-009
+        const auto &extension = formatter->getVDatumExtension();
+        if (!extension.empty()) {
+            formatter->startNode(io::WKTConstants::EXTENSION, false);
+            formatter->addQuotedString("PROJ4_GRIDS");
+            formatter->addQuotedString(extension);
+            formatter->endNode();
+        }
+    }
+    if (formatter->outputId()) {
+        formatID(formatter);
+    }
+    formatter->endNode();
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+bool VerticalReferenceFrame::_isEquivalentTo(
+    const util::IComparable *other,
+    util::IComparable::Criterion criterion) const {
+    auto otherVRF = dynamic_cast<const VerticalReferenceFrame *>(other);
+    if (otherVRF == nullptr || !Datum::_isEquivalentTo(other, criterion)) {
+        return false;
+    }
+    if ((realizationMethod().has_value() ^
+         otherVRF->realizationMethod().has_value())) {
+        return false;
+    }
+    if (realizationMethod().has_value() &&
+        otherVRF->realizationMethod().has_value()) {
+        if (*(realizationMethod()) != *(otherVRF->realizationMethod())) {
+            return false;
+        }
+    }
+    return true;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct DynamicVerticalReferenceFrame::Private {
+    common::Measure frameReferenceEpoch{};
+    util::optional<std::string> deformationModelName{};
+
+    explicit Private(const common::Measure &frameReferenceEpochIn)
+        : frameReferenceEpoch(frameReferenceEpochIn) {}
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+DynamicVerticalReferenceFrame::DynamicVerticalReferenceFrame(
+    const util::optional<RealizationMethod> &realizationMethodIn,
+    const common::Measure &frameReferenceEpochIn,
+    const util::optional<std::string> &deformationModelNameIn)
+    : VerticalReferenceFrame(realizationMethodIn),
+      d(internal::make_unique<Private>(frameReferenceEpochIn)) {
+    d->deformationModelName = deformationModelNameIn;
+}
+
+// ---------------------------------------------------------------------------
+
+#ifdef notdef
+DynamicVerticalReferenceFrame::DynamicVerticalReferenceFrame(
+    const DynamicVerticalReferenceFrame &other)
+    : VerticalReferenceFrame(other),
+      d(internal::make_unique<Private>(*other.d)) {}
+#endif
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+DynamicVerticalReferenceFrame::~DynamicVerticalReferenceFrame() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the epoch to which the coordinates of stations defining the
+ * dynamic geodetic reference frame are referenced.
+ *
+ * Usually given as a decimal year e.g. 2016.47.
+ *
+ * @return the frame reference epoch.
+ */
+const common::Measure &
+DynamicVerticalReferenceFrame::frameReferenceEpoch() const {
+    return d->frameReferenceEpoch;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the name of the deformation model.
+ *
+ * @note This is an extension to the \ref ISO_19111_2018 modeling, to
+ * hold the content of the DYNAMIC.MODEL WKT2 node.
+ *
+ * @return the name of the deformation model.
+ */
+const util::optional<std::string> &
+DynamicVerticalReferenceFrame::deformationModelName() const {
+    return d->deformationModelName;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+bool DynamicVerticalReferenceFrame::_isEquivalentTo(
+    const util::IComparable *other,
+    util::IComparable::Criterion criterion) const {
+    auto otherDGRF = dynamic_cast<const DynamicVerticalReferenceFrame *>(other);
+    if (otherDGRF == nullptr ||
+        !VerticalReferenceFrame::_isEquivalentTo(other, criterion)) {
+        return false;
+    }
+    return frameReferenceEpoch()._isEquivalentTo(
+               otherDGRF->frameReferenceEpoch(), criterion) &&
+           metadata::Identifier::isEquivalentName(
+               deformationModelName()->c_str(),
+               otherDGRF->deformationModelName()->c_str());
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void DynamicVerticalReferenceFrame::_exportToWKT(
+    io::WKTFormatter *formatter) const // throw(FormattingException)
+{
+    const bool isWKT2 = formatter->version() == io::WKTFormatter::Version::WKT2;
+    if (isWKT2 && formatter->use2018Keywords()) {
+        formatter->startNode(io::WKTConstants::DYNAMIC, false);
+        formatter->startNode(io::WKTConstants::FRAMEEPOCH, false);
+        formatter->add(
+            frameReferenceEpoch().convertToUnit(common::UnitOfMeasure::YEAR));
+        formatter->endNode();
+        if (!deformationModelName()->empty()) {
+            formatter->startNode(io::WKTConstants::MODEL, false);
+            formatter->addQuotedString(*deformationModelName());
+            formatter->endNode();
+        }
+        formatter->endNode();
+    }
+    VerticalReferenceFrame::_exportToWKT(formatter);
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a DyanmicVerticalReferenceFrame
+ *
+ * @param properties See \ref general_properties.
+ * At minimum the name should be defined.
+ * @param anchor the anchor definition, or empty.
+ * @param realizationMethodIn the realization method, or empty.
+ * @param frameReferenceEpochIn the frame reference epoch.
+ * @param deformationModelNameIn deformation model name, or empty
+ * @return new DyanmicVerticalReferenceFrame.
+ */
+DynamicVerticalReferenceFrameNNPtr DynamicVerticalReferenceFrame::create(
+    const util::PropertyMap &properties,
+    const util::optional<std::string> &anchor,
+    const util::optional<RealizationMethod> &realizationMethodIn,
+    const common::Measure &frameReferenceEpochIn,
+    const util::optional<std::string> &deformationModelNameIn) {
+    DynamicVerticalReferenceFrameNNPtr grf(
+        DynamicVerticalReferenceFrame::nn_make_shared<
+            DynamicVerticalReferenceFrame>(realizationMethodIn,
+                                           frameReferenceEpochIn,
+                                           deformationModelNameIn));
+    grf->setAnchor(anchor);
+    grf->setProperties(properties);
+    return grf;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct TemporalDatum::Private {
+    common::DateTime temporalOrigin_;
+    std::string calendar_;
+
+    Private(const common::DateTime &temporalOriginIn,
+            const std::string &calendarIn)
+        : temporalOrigin_(temporalOriginIn), calendar_(calendarIn) {}
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+TemporalDatum::TemporalDatum(const common::DateTime &temporalOriginIn,
+                             const std::string &calendarIn)
+    : d(internal::make_unique<Private>(temporalOriginIn, calendarIn)) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+TemporalDatum::~TemporalDatum() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the date and time to which temporal coordinates are
+ * referenced, expressed in conformance with ISO 8601.
+ *
+ * @return the temporal origin.
+ */
+const common::DateTime &TemporalDatum::temporalOrigin() const {
+    return d->temporalOrigin_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the calendar to which the temporal origin is referenced
+ *
+ * Default value: TemporalDatum::CALENDAR_PROLEPTIC_GREGORIAN.
+ *
+ * @return the calendar.
+ */
+const std::string &TemporalDatum::calendar() const { return d->calendar_; }
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a TemporalDatum
+ *
+ * @param properties See \ref general_properties.
+ * At minimum the name should be defined.
+ * @param temporalOriginIn the temporal origin into which temporal coordinates
+ * are referenced.
+ * @param calendarIn the calendar (generally
+ * TemporalDatum::CALENDAR_PROLEPTIC_GREGORIAN)
+ * @return new TemporalDatum.
+ */
+TemporalDatumNNPtr
+TemporalDatum::create(const util::PropertyMap &properties,
+                      const common::DateTime &temporalOriginIn,
+                      const std::string &calendarIn) {
+    auto datum(TemporalDatum::nn_make_shared<TemporalDatum>(temporalOriginIn,
+                                                            calendarIn));
+    datum->setProperties(properties);
+    return datum;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void TemporalDatum::_exportToWKT(
+    io::WKTFormatter *formatter) const // throw(FormattingException)
+{
+    const bool isWKT2 = formatter->version() == io::WKTFormatter::Version::WKT2;
+    if (!isWKT2) {
+        throw io::FormattingException(
+            "TemporalDatum can only be exported to WKT2");
+    }
+    formatter->startNode(io::WKTConstants::TDATUM, !identifiers().empty());
+    formatter->addQuotedString(nameStr());
+    if (formatter->use2018Keywords()) {
+        formatter->startNode(io::WKTConstants::CALENDAR, false);
+        formatter->addQuotedString(calendar());
+        formatter->endNode();
+    }
+
+    const auto &timeOriginStr = temporalOrigin().toString();
+    if (!timeOriginStr.empty()) {
+        formatter->startNode(io::WKTConstants::TIMEORIGIN, false);
+        if (temporalOrigin().isISO_8601()) {
+            formatter->add(timeOriginStr);
+        } else {
+            formatter->addQuotedString(timeOriginStr);
+        }
+        formatter->endNode();
+    }
+
+    formatter->endNode();
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+bool TemporalDatum::_isEquivalentTo(
+    const util::IComparable *other,
+    util::IComparable::Criterion criterion) const {
+    auto otherTD = dynamic_cast<const TemporalDatum *>(other);
+    if (otherTD == nullptr || !Datum::_isEquivalentTo(other, criterion)) {
+        return false;
+    }
+    return temporalOrigin().toString() ==
+               otherTD->temporalOrigin().toString() &&
+           calendar() == otherTD->calendar();
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct EngineeringDatum::Private {};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+EngineeringDatum::EngineeringDatum() : d(nullptr) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+EngineeringDatum::~EngineeringDatum() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a EngineeringDatum
+ *
+ * @param properties See \ref general_properties.
+ * At minimum the name should be defined.
+ * @param anchor the anchor definition, or empty.
+ * @return new EngineeringDatum.
+ */
+EngineeringDatumNNPtr
+EngineeringDatum::create(const util::PropertyMap &properties,
+                         const util::optional<std::string> &anchor) {
+    auto datum(EngineeringDatum::nn_make_shared<EngineeringDatum>());
+    datum->setAnchor(anchor);
+    datum->setProperties(properties);
+    return datum;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void EngineeringDatum::_exportToWKT(
+    io::WKTFormatter *formatter) const // throw(FormattingException)
+{
+    const bool isWKT2 = formatter->version() == io::WKTFormatter::Version::WKT2;
+    formatter->startNode(isWKT2 ? io::WKTConstants::EDATUM
+                                : io::WKTConstants::LOCAL_DATUM,
+                         !identifiers().empty());
+    formatter->addQuotedString(nameStr());
+    if (isWKT2) {
+        Datum::getPrivate()->exportAnchorDefinition(formatter);
+    } else {
+        // Somewhat picked up arbitrarily from OGC 01-009:
+        // CS_LD_Max (Attribute) : 32767
+        // Highest possible value for local datum types.
+        formatter->add(32767);
+    }
+    formatter->endNode();
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+bool EngineeringDatum::_isEquivalentTo(
+    const util::IComparable *other,
+    util::IComparable::Criterion criterion) const {
+    auto otherTD = dynamic_cast<const EngineeringDatum *>(other);
+    if (otherTD == nullptr || !Datum::_isEquivalentTo(other, criterion)) {
+        return false;
+    }
+    return true;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct ParametricDatum::Private {};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+ParametricDatum::ParametricDatum() : d(nullptr) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+ParametricDatum::~ParametricDatum() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ParametricDatum
+ *
+ * @param properties See \ref general_properties.
+ * At minimum the name should be defined.
+ * @param anchor the anchor definition, or empty.
+ * @return new ParametricDatum.
+ */
+ParametricDatumNNPtr
+ParametricDatum::create(const util::PropertyMap &properties,
+                        const util::optional<std::string> &anchor) {
+    auto datum(ParametricDatum::nn_make_shared<ParametricDatum>());
+    datum->setAnchor(anchor);
+    datum->setProperties(properties);
+    return datum;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void ParametricDatum::_exportToWKT(
+    io::WKTFormatter *formatter) const // throw(FormattingException)
+{
+    const bool isWKT2 = formatter->version() == io::WKTFormatter::Version::WKT2;
+    if (!isWKT2) {
+        throw io::FormattingException(
+            "ParametricDatum can only be exported to WKT2");
+    }
+    formatter->startNode(io::WKTConstants::PDATUM, !identifiers().empty());
+    formatter->addQuotedString(nameStr());
+    Datum::getPrivate()->exportAnchorDefinition(formatter);
+    formatter->endNode();
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+bool ParametricDatum::_isEquivalentTo(
+    const util::IComparable *other,
+    util::IComparable::Criterion criterion) const {
+    auto otherTD = dynamic_cast<const ParametricDatum *>(other);
+    if (otherTD == nullptr || !Datum::_isEquivalentTo(other, criterion)) {
+        return false;
+    }
+    return true;
+}
+//! @endcond
+
+} // namespace datum
+NS_PROJ_END
diff --git a/src/iso19111/factory.cpp b/src/iso19111/factory.cpp
new file mode 100644
index 00000000..47d31db9
--- /dev/null
+++ b/src/iso19111/factory.cpp
@@ -0,0 +1,4973 @@
+/******************************************************************************
+ *
+ * Project:  PROJ
+ * Purpose:  ISO19111:2018 implementation
+ * Author:   Even Rouault <even dot rouault at spatialys dot com>
+ *
+ ******************************************************************************
+ * Copyright (c) 2018, Even Rouault <even dot rouault at spatialys dot com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ ****************************************************************************/
+
+#ifndef FROM_PROJ_CPP
+#define FROM_PROJ_CPP
+#endif
+
+#include "proj/common.hpp"
+#include "proj/coordinateoperation.hpp"
+#include "proj/coordinatesystem.hpp"
+#include "proj/crs.hpp"
+#include "proj/datum.hpp"
+#include "proj/io.hpp"
+#include "proj/metadata.hpp"
+#include "proj/util.hpp"
+
+#include "proj/internal/coordinateoperation_internal.hpp"
+#include "proj/internal/internal.hpp"
+#include "proj/internal/io_internal.hpp"
+#include "proj/internal/lru_cache.hpp"
+
+#include <cmath>
+#include <cstdlib>
+#include <cstring>
+#include <iomanip>
+#include <limits>
+#include <map>
+#include <memory>
+#include <sstream> // std::ostringstream
+#include <string>
+
+#include "proj_constants.h"
+
+// PROJ include order is sensitive
+// clang-format off
+#include "proj.h"
+#include "projects.h"
+// clang-format on
+
+#include <sqlite3.h>
+
+// Custom SQLite VFS as our database is not supposed to be modified in
+// parallel. This is slightly faster
+#define ENABLE_CUSTOM_LOCKLESS_VFS
+
+using namespace NS_PROJ::internal;
+using namespace NS_PROJ::common;
+
+NS_PROJ_START
+namespace io {
+
+//! @cond Doxygen_Suppress
+
+#define GEOG_2D "'geographic 2D'"
+#define GEOG_3D "'geographic 3D'"
+#define GEOCENTRIC "'geocentric'"
+
+// ---------------------------------------------------------------------------
+
+struct SQLValues {
+    enum class Type { STRING, DOUBLE };
+
+    // cppcheck-suppress noExplicitConstructor
+    SQLValues(const std::string &value) : type_(Type::STRING), str_(value) {}
+
+    // cppcheck-suppress noExplicitConstructor
+    SQLValues(double value) : type_(Type::DOUBLE), double_(value) {}
+
+    const Type &type() const { return type_; }
+
+    // cppcheck-suppress functionStatic
+    const std::string &stringValue() const { return str_; }
+
+    // cppcheck-suppress functionStatic
+    double doubleValue() const { return double_; }
+
+  private:
+    Type type_;
+    std::string str_{};
+    double double_ = 0.0;
+};
+
+// ---------------------------------------------------------------------------
+
+using SQLRow = std::vector<std::string>;
+using SQLResultSet = std::list<SQLRow>;
+using ListOfParams = std::list<SQLValues>;
+
+// ---------------------------------------------------------------------------
+
+struct DatabaseContext::Private {
+    Private();
+    ~Private();
+
+    void open(const std::string &databasePath = std::string());
+    void setHandle(sqlite3 *sqlite_handle);
+
+    sqlite3 *handle() const { return sqlite_handle_; }
+
+    PJ_CONTEXT *pjCtxt() const { return pjCtxt_; }
+    void setPjCtxt(PJ_CONTEXT *ctxt) { pjCtxt_ = ctxt; }
+
+    SQLResultSet run(const std::string &sql,
+                     const ListOfParams &parameters = ListOfParams());
+
+    std::vector<std::string> getDatabaseStructure();
+
+    // cppcheck-suppress functionStatic
+    const std::string &getPath() const { return databasePath_; }
+
+    void attachExtraDatabases(
+        const std::vector<std::string> &auxiliaryDatabasePaths);
+
+    // Mechanism to detect recursion in calls from
+    // AuthorityFactory::createXXX() -> createFromUserInput() ->
+    // AuthorityFactory::createXXX()
+    struct RecursionDetector {
+        explicit RecursionDetector(const DatabaseContextNNPtr &context)
+            : dbContext_(context) {
+            if (dbContext_->getPrivate()->recLevel_ == 2) {
+                // Throw exception before incrementing, since the destructor
+                // will not be called
+                throw FactoryException("Too many recursive calls");
+            }
+            ++dbContext_->getPrivate()->recLevel_;
+        }
+
+        ~RecursionDetector() { --dbContext_->getPrivate()->recLevel_; }
+
+      private:
+        DatabaseContextNNPtr dbContext_;
+    };
+
+    std::map<std::string, std::list<SQLRow>> &getMapCanonicalizeGRFName() {
+        return mapCanonicalizeGRFName_;
+    }
+
+    // cppcheck-suppress functionStatic
+    common::UnitOfMeasurePtr getUOMFromCache(const std::string &code);
+    // cppcheck-suppress functionStatic
+    void cache(const std::string &code, const common::UnitOfMeasureNNPtr &uom);
+
+    // cppcheck-suppress functionStatic
+    crs::CRSPtr getCRSFromCache(const std::string &code);
+    // cppcheck-suppress functionStatic
+    void cache(const std::string &code, const crs::CRSNNPtr &crs);
+
+    datum::GeodeticReferenceFramePtr
+        // cppcheck-suppress functionStatic
+        getGeodeticDatumFromCache(const std::string &code);
+    // cppcheck-suppress functionStatic
+    void cache(const std::string &code,
+               const datum::GeodeticReferenceFrameNNPtr &datum);
+
+    datum::PrimeMeridianPtr
+        // cppcheck-suppress functionStatic
+        getPrimeMeridianFromCache(const std::string &code);
+    // cppcheck-suppress functionStatic
+    void cache(const std::string &code, const datum::PrimeMeridianNNPtr &pm);
+
+    // cppcheck-suppress functionStatic
+    cs::CoordinateSystemPtr
+    getCoordinateSystemFromCache(const std::string &code);
+    // cppcheck-suppress functionStatic
+    void cache(const std::string &code, const cs::CoordinateSystemNNPtr &cs);
+
+    // cppcheck-suppress functionStatic
+    metadata::ExtentPtr getExtentFromCache(const std::string &code);
+    // cppcheck-suppress functionStatic
+    void cache(const std::string &code, const metadata::ExtentNNPtr &extent);
+
+    // cppcheck-suppress functionStatic
+    bool getCRSToCRSCoordOpFromCache(
+        const std::string &code,
+        std::vector<operation::CoordinateOperationNNPtr> &list);
+    // cppcheck-suppress functionStatic
+    void cache(const std::string &code,
+               const std::vector<operation::CoordinateOperationNNPtr> &list);
+
+    struct GridInfoCache {
+        std::string fullFilename{};
+        std::string packageName{};
+        std::string url{};
+        bool found = false;
+        bool directDownload = false;
+        bool openLicense = false;
+        bool gridAvailable = false;
+    };
+
+    // cppcheck-suppress functionStatic
+    bool getGridInfoFromCache(const std::string &code, GridInfoCache &info);
+    // cppcheck-suppress functionStatic
+    void cache(const std::string &code, const GridInfoCache &info);
+
+  private:
+    friend class DatabaseContext;
+
+    std::string databasePath_{};
+    bool close_handle_ = true;
+    sqlite3 *sqlite_handle_{};
+    std::map<std::string, sqlite3_stmt *> mapSqlToStatement_{};
+    PJ_CONTEXT *pjCtxt_ = nullptr;
+    int recLevel_ = 0;
+    bool detach_ = false;
+    std::string lastMetadataValue_{};
+    std::map<std::string, std::list<SQLRow>> mapCanonicalizeGRFName_{};
+
+    using LRUCacheOfObjects = lru11::Cache<std::string, util::BaseObjectPtr>;
+
+    static constexpr size_t CACHE_SIZE = 128;
+    LRUCacheOfObjects cacheUOM_{CACHE_SIZE};
+    LRUCacheOfObjects cacheCRS_{CACHE_SIZE};
+    LRUCacheOfObjects cacheGeodeticDatum_{CACHE_SIZE};
+    LRUCacheOfObjects cachePrimeMeridian_{CACHE_SIZE};
+    LRUCacheOfObjects cacheCS_{CACHE_SIZE};
+    LRUCacheOfObjects cacheExtent_{CACHE_SIZE};
+    lru11::Cache<std::string, std::vector<operation::CoordinateOperationNNPtr>>
+        cacheCRSToCrsCoordOp_{CACHE_SIZE};
+    lru11::Cache<std::string, GridInfoCache> cacheGridInfo_{CACHE_SIZE};
+
+    static void insertIntoCache(LRUCacheOfObjects &cache,
+                                const std::string &code,
+                                const util::BaseObjectPtr &obj);
+
+    static void getFromCache(LRUCacheOfObjects &cache, const std::string &code,
+                             util::BaseObjectPtr &obj);
+
+    void closeDB();
+
+    // cppcheck-suppress functionStatic
+    void registerFunctions();
+
+#ifdef ENABLE_CUSTOM_LOCKLESS_VFS
+    std::string thisNamePtr_{};
+    sqlite3_vfs *vfs_{};
+    bool createCustomVFS();
+#endif
+
+    Private(const Private &) = delete;
+    Private &operator=(const Private &) = delete;
+};
+
+// ---------------------------------------------------------------------------
+
+DatabaseContext::Private::Private() = default;
+
+// ---------------------------------------------------------------------------
+
+DatabaseContext::Private::~Private() {
+    assert(recLevel_ == 0);
+
+    closeDB();
+
+#ifdef ENABLE_CUSTOM_LOCKLESS_VFS
+    if (vfs_) {
+        sqlite3_vfs_unregister(vfs_);
+        delete vfs_;
+    }
+#endif
+}
+
+// ---------------------------------------------------------------------------
+
+void DatabaseContext::Private::closeDB() {
+
+    if (detach_) {
+        // Workaround a bug visible in SQLite 3.8.1 and 3.8.2 that causes
+        // a crash in TEST(factory, attachExtraDatabases_auxiliary)
+        // due to possible wrong caching of key info.
+        // The bug is specific to using a memory file with shared cache as an
+        // auxiliary DB.
+        // The efinitive fix was likely in 3.8.8
+        // https://github.com/mackyle/sqlite/commit/d412d4b8731991ecbd8811874aa463d0821673eb
+        // But just after 3.8.2,
+        // https://github.com/mackyle/sqlite/commit/ccf328c4318eacedab9ed08c404bc4f402dcad19
+        // also seemed to hide the issue.
+        // Detaching a database hides the issue, not sure if it is by chance...
+        run("DETACH DATABASE db_0");
+        detach_ = false;
+    }
+
+    for (auto &pair : mapSqlToStatement_) {
+        sqlite3_finalize(pair.second);
+    }
+    mapSqlToStatement_.clear();
+
+    if (close_handle_ && sqlite_handle_ != nullptr) {
+        sqlite3_close(sqlite_handle_);
+        sqlite_handle_ = nullptr;
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+void DatabaseContext::Private::insertIntoCache(LRUCacheOfObjects &cache,
+                                               const std::string &code,
+                                               const util::BaseObjectPtr &obj) {
+    cache.insert(code, obj);
+}
+
+// ---------------------------------------------------------------------------
+
+void DatabaseContext::Private::getFromCache(LRUCacheOfObjects &cache,
+                                            const std::string &code,
+                                            util::BaseObjectPtr &obj) {
+    cache.tryGet(code, obj);
+}
+
+// ---------------------------------------------------------------------------
+
+bool DatabaseContext::Private::getCRSToCRSCoordOpFromCache(
+    const std::string &code,
+    std::vector<operation::CoordinateOperationNNPtr> &list) {
+    return cacheCRSToCrsCoordOp_.tryGet(code, list);
+}
+
+// ---------------------------------------------------------------------------
+
+void DatabaseContext::Private::cache(
+    const std::string &code,
+    const std::vector<operation::CoordinateOperationNNPtr> &list) {
+    cacheCRSToCrsCoordOp_.insert(code, list);
+}
+
+// ---------------------------------------------------------------------------
+
+crs::CRSPtr DatabaseContext::Private::getCRSFromCache(const std::string &code) {
+    util::BaseObjectPtr obj;
+    getFromCache(cacheCRS_, code, obj);
+    return std::static_pointer_cast<crs::CRS>(obj);
+}
+
+// ---------------------------------------------------------------------------
+
+void DatabaseContext::Private::cache(const std::string &code,
+                                     const crs::CRSNNPtr &crs) {
+    insertIntoCache(cacheCRS_, code, crs.as_nullable());
+}
+
+// ---------------------------------------------------------------------------
+
+common::UnitOfMeasurePtr
+DatabaseContext::Private::getUOMFromCache(const std::string &code) {
+    util::BaseObjectPtr obj;
+    getFromCache(cacheUOM_, code, obj);
+    return std::static_pointer_cast<common::UnitOfMeasure>(obj);
+}
+
+// ---------------------------------------------------------------------------
+
+void DatabaseContext::Private::cache(const std::string &code,
+                                     const common::UnitOfMeasureNNPtr &uom) {
+    insertIntoCache(cacheUOM_, code, uom.as_nullable());
+}
+
+// ---------------------------------------------------------------------------
+
+datum::GeodeticReferenceFramePtr
+DatabaseContext::Private::getGeodeticDatumFromCache(const std::string &code) {
+    util::BaseObjectPtr obj;
+    getFromCache(cacheGeodeticDatum_, code, obj);
+    return std::static_pointer_cast<datum::GeodeticReferenceFrame>(obj);
+}
+
+// ---------------------------------------------------------------------------
+
+void DatabaseContext::Private::cache(
+    const std::string &code, const datum::GeodeticReferenceFrameNNPtr &datum) {
+    insertIntoCache(cacheGeodeticDatum_, code, datum.as_nullable());
+}
+
+// ---------------------------------------------------------------------------
+
+datum::PrimeMeridianPtr
+DatabaseContext::Private::getPrimeMeridianFromCache(const std::string &code) {
+    util::BaseObjectPtr obj;
+    getFromCache(cachePrimeMeridian_, code, obj);
+    return std::static_pointer_cast<datum::PrimeMeridian>(obj);
+}
+
+// ---------------------------------------------------------------------------
+
+void DatabaseContext::Private::cache(const std::string &code,
+                                     const datum::PrimeMeridianNNPtr &pm) {
+    insertIntoCache(cachePrimeMeridian_, code, pm.as_nullable());
+}
+
+// ---------------------------------------------------------------------------
+
+cs::CoordinateSystemPtr DatabaseContext::Private::getCoordinateSystemFromCache(
+    const std::string &code) {
+    util::BaseObjectPtr obj;
+    getFromCache(cacheCS_, code, obj);
+    return std::static_pointer_cast<cs::CoordinateSystem>(obj);
+}
+
+// ---------------------------------------------------------------------------
+
+void DatabaseContext::Private::cache(const std::string &code,
+                                     const cs::CoordinateSystemNNPtr &cs) {
+    insertIntoCache(cacheCS_, code, cs.as_nullable());
+}
+
+// ---------------------------------------------------------------------------
+
+metadata::ExtentPtr
+DatabaseContext::Private::getExtentFromCache(const std::string &code) {
+    util::BaseObjectPtr obj;
+    getFromCache(cacheExtent_, code, obj);
+    return std::static_pointer_cast<metadata::Extent>(obj);
+}
+
+// ---------------------------------------------------------------------------
+
+void DatabaseContext::Private::cache(const std::string &code,
+                                     const metadata::ExtentNNPtr &extent) {
+    insertIntoCache(cacheExtent_, code, extent.as_nullable());
+}
+
+// ---------------------------------------------------------------------------
+
+bool DatabaseContext::Private::getGridInfoFromCache(const std::string &code,
+                                                    GridInfoCache &info) {
+    return cacheGridInfo_.tryGet(code, info);
+}
+
+// ---------------------------------------------------------------------------
+
+void DatabaseContext::Private::cache(const std::string &code,
+                                     const GridInfoCache &info) {
+    cacheGridInfo_.insert(code, info);
+}
+
+// ---------------------------------------------------------------------------
+
+#ifdef ENABLE_CUSTOM_LOCKLESS_VFS
+
+typedef int (*ClosePtr)(sqlite3_file *);
+
+static int VFSClose(sqlite3_file *file) {
+    sqlite3_vfs *defaultVFS = sqlite3_vfs_find(nullptr);
+    assert(defaultVFS);
+    ClosePtr defaultClosePtr;
+    std::memcpy(&defaultClosePtr,
+                reinterpret_cast<char *>(file) + defaultVFS->szOsFile,
+                sizeof(ClosePtr));
+    void *methods = const_cast<sqlite3_io_methods *>(file->pMethods);
+    int ret = defaultClosePtr(file);
+    std::free(methods);
+    return ret;
+}
+
+// No-lock implementation
+static int VSFLock(sqlite3_file *, int) { return SQLITE_OK; }
+
+static int VSFUnlock(sqlite3_file *, int) { return SQLITE_OK; }
+
+static int VFSOpen(sqlite3_vfs *vfs, const char *name, sqlite3_file *file,
+                   int flags, int *outFlags) {
+    sqlite3_vfs *defaultVFS = static_cast<sqlite3_vfs *>(vfs->pAppData);
+    int ret = defaultVFS->xOpen(defaultVFS, name, file, flags, outFlags);
+    if (ret == SQLITE_OK) {
+        ClosePtr defaultClosePtr = file->pMethods->xClose;
+        assert(defaultClosePtr);
+        sqlite3_io_methods *methods = static_cast<sqlite3_io_methods *>(
+            std::malloc(sizeof(sqlite3_io_methods)));
+        if (!methods) {
+            file->pMethods->xClose(file);
+            return SQLITE_NOMEM;
+        }
+        memcpy(methods, file->pMethods, sizeof(sqlite3_io_methods));
+        methods->xClose = VFSClose;
+        methods->xLock = VSFLock;
+        methods->xUnlock = VSFUnlock;
+        file->pMethods = methods;
+        // Save original xClose pointer at end of file structure
+        std::memcpy(reinterpret_cast<char *>(file) + defaultVFS->szOsFile,
+                    &defaultClosePtr, sizeof(ClosePtr));
+    }
+    return ret;
+}
+
+static int VFSAccess(sqlite3_vfs *vfs, const char *zName, int flags,
+                     int *pResOut) {
+    sqlite3_vfs *defaultVFS = static_cast<sqlite3_vfs *>(vfs->pAppData);
+    // Do not bother stat'ing for journal or wal files
+    if (std::strstr(zName, "-journal") || std::strstr(zName, "-wal")) {
+        *pResOut = false;
+        return SQLITE_OK;
+    }
+    return defaultVFS->xAccess(defaultVFS, zName, flags, pResOut);
+}
+
+// ---------------------------------------------------------------------------
+
+bool DatabaseContext::Private::createCustomVFS() {
+
+    sqlite3_vfs *defaultVFS = sqlite3_vfs_find(nullptr);
+    assert(defaultVFS);
+
+    std::ostringstream buffer;
+    buffer << this;
+    thisNamePtr_ = buffer.str();
+
+    vfs_ = new sqlite3_vfs();
+    vfs_->iVersion = 1;
+    vfs_->szOsFile = defaultVFS->szOsFile + sizeof(ClosePtr);
+    vfs_->mxPathname = defaultVFS->mxPathname;
+    vfs_->zName = thisNamePtr_.c_str();
+    vfs_->pAppData = defaultVFS;
+    vfs_->xOpen = VFSOpen;
+    vfs_->xDelete = defaultVFS->xDelete;
+    vfs_->xAccess = VFSAccess;
+    vfs_->xFullPathname = defaultVFS->xFullPathname;
+    vfs_->xDlOpen = defaultVFS->xDlOpen;
+    vfs_->xDlError = defaultVFS->xDlError;
+    vfs_->xDlSym = defaultVFS->xDlSym;
+    vfs_->xDlClose = defaultVFS->xDlClose;
+    vfs_->xRandomness = defaultVFS->xRandomness;
+    vfs_->xSleep = defaultVFS->xSleep;
+    vfs_->xCurrentTime = defaultVFS->xCurrentTime;
+    vfs_->xGetLastError = defaultVFS->xGetLastError;
+    vfs_->xCurrentTimeInt64 = defaultVFS->xCurrentTimeInt64;
+    return sqlite3_vfs_register(vfs_, false) == SQLITE_OK;
+}
+
+#endif // ENABLE_CUSTOM_LOCKLESS_VFS
+
+// ---------------------------------------------------------------------------
+
+void DatabaseContext::Private::open(const std::string &databasePath) {
+    std::string path(databasePath);
+    if (path.empty()) {
+        const char *proj_lib = std::getenv("PROJ_LIB");
+#ifdef PROJ_LIB
+        if (!proj_lib) {
+            proj_lib = PROJ_LIB;
+        }
+#endif
+        if (!proj_lib) {
+            throw FactoryException(
+                "Cannot find proj.db due to missing PROJ_LIB");
+        }
+        path = std::string(proj_lib) + DIR_CHAR + "proj.db";
+    }
+
+    if (
+#ifdef ENABLE_CUSTOM_LOCKLESS_VFS
+        !createCustomVFS() ||
+#endif
+        sqlite3_open_v2(path.c_str(), &sqlite_handle_,
+                        SQLITE_OPEN_READONLY | SQLITE_OPEN_NOMUTEX,
+#ifdef ENABLE_CUSTOM_LOCKLESS_VFS
+                        thisNamePtr_.c_str()
+#else
+                        nullptr
+#endif
+                            ) != SQLITE_OK ||
+        !sqlite_handle_) {
+        throw FactoryException("Open of " + path + " failed");
+    }
+
+    databasePath_ = path;
+    registerFunctions();
+}
+
+// ---------------------------------------------------------------------------
+
+void DatabaseContext::Private::setHandle(sqlite3 *sqlite_handle) {
+
+    assert(sqlite_handle);
+    assert(!sqlite_handle_);
+    sqlite_handle_ = sqlite_handle;
+    close_handle_ = false;
+
+    registerFunctions();
+}
+
+// ---------------------------------------------------------------------------
+
+std::vector<std::string> DatabaseContext::Private::getDatabaseStructure() {
+    auto sqlRes = run("SELECT sql FROM sqlite_master WHERE type "
+                      "IN ('table', 'trigger', 'view') ORDER BY type");
+    std::vector<std::string> res;
+    for (const auto &row : sqlRes) {
+        res.emplace_back(row[0]);
+    }
+    return res;
+}
+
+// ---------------------------------------------------------------------------
+
+void DatabaseContext::Private::attachExtraDatabases(
+    const std::vector<std::string> &auxiliaryDatabasePaths) {
+    assert(close_handle_);
+    assert(sqlite_handle_);
+
+    auto tables =
+        run("SELECT name FROM sqlite_master WHERE type IN ('table', 'view')");
+    std::map<std::string, std::vector<std::string>> tableStructure;
+    for (const auto &rowTable : tables) {
+        auto tableName = rowTable[0];
+        auto tableInfo = run("PRAGMA table_info(\"" +
+                             replaceAll(tableName, "\"", "\"\"") + "\")");
+        for (const auto &rowCol : tableInfo) {
+            const auto &colName = rowCol[1];
+            tableStructure[tableName].push_back(colName);
+        }
+    }
+
+    closeDB();
+
+    sqlite3_open_v2(":memory:", &sqlite_handle_,
+                    SQLITE_OPEN_READWRITE | SQLITE_OPEN_NOMUTEX
+#ifdef SQLITE_OPEN_URI
+                        | SQLITE_OPEN_URI
+#endif
+                    ,
+                    nullptr);
+    if (!sqlite_handle_) {
+        throw FactoryException("cannot create in memory database");
+    }
+
+    run("ATTACH DATABASE '" + replaceAll(databasePath_, "'", "''") +
+        "' AS db_0");
+    detach_ = true;
+    int count = 1;
+    for (const auto &otherDb : auxiliaryDatabasePaths) {
+        std::string sql = "ATTACH DATABASE '";
+        sql += replaceAll(otherDb, "'", "''");
+        sql += "' AS db_";
+        sql += toString(static_cast<int>(count));
+        count++;
+        run(sql);
+    }
+
+    for (const auto &pair : tableStructure) {
+        std::string sql("CREATE TEMP VIEW ");
+        sql += pair.first;
+        sql += " AS ";
+        for (size_t i = 0; i <= auxiliaryDatabasePaths.size(); ++i) {
+            std::string selectFromAux("SELECT ");
+            bool firstCol = true;
+            for (const auto &colName : pair.second) {
+                if (!firstCol) {
+                    selectFromAux += ", ";
+                }
+                firstCol = false;
+                selectFromAux += colName;
+            }
+            selectFromAux += " FROM db_";
+            selectFromAux += toString(static_cast<int>(i));
+            selectFromAux += ".";
+            selectFromAux += pair.first;
+
+            try {
+                // Check that the request will succeed. In case of 'sparse'
+                // databases...
+                run(selectFromAux + " LIMIT 0");
+
+                if (i > 0) {
+                    sql += " UNION ALL ";
+                }
+                sql += selectFromAux;
+            } catch (const std::exception &) {
+            }
+        }
+        run(sql);
+    }
+
+    registerFunctions();
+}
+
+// ---------------------------------------------------------------------------
+
+static double PROJ_SQLITE_GetValAsDouble(sqlite3_value *val, bool &gotVal) {
+    switch (sqlite3_value_type(val)) {
+    case SQLITE_FLOAT:
+        gotVal = true;
+        return sqlite3_value_double(val);
+
+    case SQLITE_INTEGER:
+        gotVal = true;
+        return static_cast<double>(sqlite3_value_int64(val));
+
+    default:
+        gotVal = false;
+        return 0.0;
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+static void PROJ_SQLITE_pseudo_area_from_swne(sqlite3_context *pContext,
+                                              int /* argc */,
+                                              sqlite3_value **argv) {
+    bool b0, b1, b2, b3;
+    double south_lat = PROJ_SQLITE_GetValAsDouble(argv[0], b0);
+    double west_lon = PROJ_SQLITE_GetValAsDouble(argv[1], b1);
+    double north_lat = PROJ_SQLITE_GetValAsDouble(argv[2], b2);
+    double east_lon = PROJ_SQLITE_GetValAsDouble(argv[3], b3);
+    if (!b0 || !b1 || !b2 || !b3) {
+        sqlite3_result_null(pContext);
+        return;
+    }
+    // Deal with area crossing antimeridian
+    if (east_lon < west_lon) {
+        east_lon += 360.0;
+    }
+    // Integrate cos(lat) between south_lat and north_lat
+    double pseudo_area = (east_lon - west_lon) *
+                         (std::sin(common::Angle(north_lat).getSIValue()) -
+                          std::sin(common::Angle(south_lat).getSIValue()));
+    sqlite3_result_double(pContext, pseudo_area);
+}
+
+// ---------------------------------------------------------------------------
+
+static void PROJ_SQLITE_intersects_bbox(sqlite3_context *pContext,
+                                        int /* argc */, sqlite3_value **argv) {
+    bool b0, b1, b2, b3, b4, b5, b6, b7;
+    double south_lat1 = PROJ_SQLITE_GetValAsDouble(argv[0], b0);
+    double west_lon1 = PROJ_SQLITE_GetValAsDouble(argv[1], b1);
+    double north_lat1 = PROJ_SQLITE_GetValAsDouble(argv[2], b2);
+    double east_lon1 = PROJ_SQLITE_GetValAsDouble(argv[3], b3);
+    double south_lat2 = PROJ_SQLITE_GetValAsDouble(argv[4], b4);
+    double west_lon2 = PROJ_SQLITE_GetValAsDouble(argv[5], b5);
+    double north_lat2 = PROJ_SQLITE_GetValAsDouble(argv[6], b6);
+    double east_lon2 = PROJ_SQLITE_GetValAsDouble(argv[7], b7);
+    if (!b0 || !b1 || !b2 || !b3 || !b4 || !b5 || !b6 || !b7) {
+        sqlite3_result_null(pContext);
+        return;
+    }
+    auto bbox1 = metadata::GeographicBoundingBox::create(west_lon1, south_lat1,
+                                                         east_lon1, north_lat1);
+    auto bbox2 = metadata::GeographicBoundingBox::create(west_lon2, south_lat2,
+                                                         east_lon2, north_lat2);
+    sqlite3_result_int(pContext, bbox1->intersects(bbox2) ? 1 : 0);
+}
+
+// ---------------------------------------------------------------------------
+
+#ifndef SQLITE_DETERMINISTIC
+#define SQLITE_DETERMINISTIC 0
+#endif
+
+void DatabaseContext::Private::registerFunctions() {
+    sqlite3_create_function(sqlite_handle_, "pseudo_area_from_swne", 4,
+                            SQLITE_UTF8 | SQLITE_DETERMINISTIC, nullptr,
+                            PROJ_SQLITE_pseudo_area_from_swne, nullptr,
+                            nullptr);
+
+    sqlite3_create_function(sqlite_handle_, "intersects_bbox", 8,
+                            SQLITE_UTF8 | SQLITE_DETERMINISTIC, nullptr,
+                            PROJ_SQLITE_intersects_bbox, nullptr, nullptr);
+}
+
+// ---------------------------------------------------------------------------
+
+SQLResultSet DatabaseContext::Private::run(const std::string &sql,
+                                           const ListOfParams &parameters) {
+
+    sqlite3_stmt *stmt = nullptr;
+    auto iter = mapSqlToStatement_.find(sql);
+    if (iter != mapSqlToStatement_.end()) {
+        stmt = iter->second;
+        sqlite3_reset(stmt);
+    } else {
+        if (sqlite3_prepare_v2(sqlite_handle_, sql.c_str(),
+                               static_cast<int>(sql.size()), &stmt,
+                               nullptr) != SQLITE_OK) {
+            throw FactoryException("SQLite error on " + sql + ": " +
+                                   sqlite3_errmsg(sqlite_handle_));
+        }
+        mapSqlToStatement_.insert(
+            std::pair<std::string, sqlite3_stmt *>(sql, stmt));
+    }
+
+    int nBindField = 1;
+    for (const auto &param : parameters) {
+        if (param.type() == SQLValues::Type::STRING) {
+            auto strValue = param.stringValue();
+            sqlite3_bind_text(stmt, nBindField, strValue.c_str(),
+                              static_cast<int>(strValue.size()),
+                              SQLITE_TRANSIENT);
+        } else {
+            assert(param.type() == SQLValues::Type::DOUBLE);
+            sqlite3_bind_double(stmt, nBindField, param.doubleValue());
+        }
+        nBindField++;
+    }
+
+    SQLResultSet result;
+    const int column_count = sqlite3_column_count(stmt);
+    while (true) {
+        int ret = sqlite3_step(stmt);
+        if (ret == SQLITE_ROW) {
+            SQLRow row(column_count);
+            for (int i = 0; i < column_count; i++) {
+                const char *txt = reinterpret_cast<const char *>(
+                    sqlite3_column_text(stmt, i));
+                if (txt) {
+                    row[i] = txt;
+                }
+            }
+            result.emplace_back(std::move(row));
+        } else if (ret == SQLITE_DONE) {
+            break;
+        } else {
+            throw FactoryException("SQLite error on " + sql + ": " +
+                                   sqlite3_errmsg(sqlite_handle_));
+        }
+    }
+    return result;
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+DatabaseContext::~DatabaseContext() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+DatabaseContext::DatabaseContext() : d(internal::make_unique<Private>()) {}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a database context, using the default proj.db file
+ *
+ * It will be searched in the directory pointed by the PROJ_LIB environment
+ * variable. If not found, on Unix builds, it will be then searched first in
+ * the pkgdatadir directory of the installation prefix.
+ *
+ * This database context should be used only by one thread at a time.
+ * @throw FactoryException
+ */
+DatabaseContextNNPtr DatabaseContext::create() {
+    return create(std::string(), {});
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a database context from a full filename.
+ *
+ * This database context should be used only by one thread at a time.
+ * @param databasePath Path and filename of the database. Might be empty
+ * string for the default rules to locate the default proj.db
+ * @throw FactoryException
+ */
+DatabaseContextNNPtr DatabaseContext::create(const std::string &databasePath) {
+    return create(databasePath, {});
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a database context from a full filename, and attach
+ * auxiliary databases to it.
+ *
+ * This database context should be used only by one thread at a time.
+ * @param databasePath Path and filename of the database. Might be empty
+ * string for the default rules to locate the default proj.db
+ * @param auxiliaryDatabasePaths Path and filename of auxiliary databases;
+ * @throw FactoryException
+ */
+DatabaseContextNNPtr DatabaseContext::create(
+    const std::string &databasePath,
+    const std::vector<std::string> &auxiliaryDatabasePaths) {
+    auto ctxt = DatabaseContext::nn_make_shared<DatabaseContext>();
+    ctxt->getPrivate()->open(databasePath);
+    if (!auxiliaryDatabasePaths.empty()) {
+        ctxt->getPrivate()->attachExtraDatabases(auxiliaryDatabasePaths);
+    }
+    return ctxt;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the list of authorities used in the database.
+ */
+std::set<std::string> DatabaseContext::getAuthorities() const {
+    auto res = d->run("SELECT auth_name FROM authority_list");
+    std::set<std::string> list;
+    for (const auto &row : res) {
+        list.insert(row[0]);
+    }
+    return list;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the list of SQL commands (CREATE TABLE, CREATE TRIGGER,
+ * CREATE VIEW) needed to initialize a new database.
+ */
+std::vector<std::string> DatabaseContext::getDatabaseStructure() const {
+    return d->getDatabaseStructure();
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the path to the database.
+ */
+const std::string &DatabaseContext::getPath() const { return d->getPath(); }
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return a metadata item.
+ *
+ * Value remains valid while this is alive and to the next call to getMetadata
+ */
+const char *DatabaseContext::getMetadata(const char *key) const {
+    auto res =
+        d->run("SELECT value FROM metadata WHERE key = ?", {std::string(key)});
+    if (res.empty()) {
+        return nullptr;
+    }
+    d->lastMetadataValue_ = res.front()[0];
+    return d->lastMetadataValue_.c_str();
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+DatabaseContextNNPtr DatabaseContext::create(void *sqlite_handle) {
+    auto ctxt = DatabaseContext::nn_make_shared<DatabaseContext>();
+    ctxt->getPrivate()->setHandle(static_cast<sqlite3 *>(sqlite_handle));
+    return ctxt;
+}
+
+// ---------------------------------------------------------------------------
+
+void *DatabaseContext::getSqliteHandle() const {
+    return getPrivate()->handle();
+}
+
+// ---------------------------------------------------------------------------
+
+void DatabaseContext::attachPJContext(void *pjCtxt) {
+    d->setPjCtxt(static_cast<PJ_CONTEXT *>(pjCtxt));
+}
+
+// ---------------------------------------------------------------------------
+
+bool DatabaseContext::lookForGridAlternative(const std::string &officialName,
+                                             std::string &projFilename,
+                                             std::string &projFormat,
+                                             bool &inverse) const {
+    auto res = d->run(
+        "SELECT proj_grid_name, proj_grid_format, inverse_direction FROM "
+        "grid_alternatives WHERE original_grid_name = ?",
+        {officialName});
+    if (res.empty()) {
+        return false;
+    }
+    const auto &row = res.front();
+    projFilename = row[0];
+    projFormat = row[1];
+    inverse = row[2] == "1";
+    return true;
+}
+
+// ---------------------------------------------------------------------------
+
+bool DatabaseContext::lookForGridInfo(const std::string &projFilename,
+                                      std::string &fullFilename,
+                                      std::string &packageName,
+                                      std::string &url, bool &directDownload,
+                                      bool &openLicense,
+                                      bool &gridAvailable) const {
+    Private::GridInfoCache info;
+    if (d->getGridInfoFromCache(projFilename, info)) {
+        fullFilename = info.fullFilename;
+        packageName = info.packageName;
+        url = info.url;
+        directDownload = info.directDownload;
+        openLicense = info.openLicense;
+        gridAvailable = info.gridAvailable;
+        return info.found;
+    }
+
+    fullFilename.clear();
+    packageName.clear();
+    url.clear();
+    openLicense = false;
+    directDownload = false;
+
+    fullFilename.resize(2048);
+    if (d->pjCtxt() == nullptr) {
+        d->setPjCtxt(pj_get_default_ctx());
+    }
+    gridAvailable =
+        pj_find_file(d->pjCtxt(), projFilename.c_str(), &fullFilename[0],
+                     fullFilename.size() - 1) != 0;
+    fullFilename.resize(strlen(fullFilename.c_str()));
+
+    auto res =
+        d->run("SELECT "
+               "grid_packages.package_name, "
+               "grid_alternatives.url, "
+               "grid_packages.url AS package_url, "
+               "grid_alternatives.open_license, "
+               "grid_packages.open_license AS package_open_license, "
+               "grid_alternatives.direct_download, "
+               "grid_packages.direct_download AS package_direct_download "
+               "FROM grid_alternatives "
+               "LEFT JOIN grid_packages ON "
+               "grid_alternatives.package_name = grid_packages.package_name "
+               "WHERE proj_grid_name = ?",
+               {projFilename});
+    bool ret = !res.empty();
+    if (ret) {
+        const auto &row = res.front();
+        packageName = std::move(row[0]);
+        url = row[1].empty() ? std::move(row[2]) : std::move(row[1]);
+        openLicense = (row[3].empty() ? row[4] : row[3]) == "1";
+        directDownload = (row[5].empty() ? row[6] : row[5]) == "1";
+
+        info.fullFilename = fullFilename;
+        info.packageName = packageName;
+        info.url = url;
+        info.directDownload = directDownload;
+        info.openLicense = openLicense;
+        info.gridAvailable = gridAvailable;
+    }
+    info.found = ret;
+    d->cache(projFilename, info);
+    return ret;
+}
+
+// ---------------------------------------------------------------------------
+
+bool DatabaseContext::isKnownName(const std::string &name,
+                                  const std::string &tableName) const {
+    std::string sql("SELECT 1 FROM \"");
+    sql += replaceAll(tableName, "\"", "\"\"");
+    sql += "\" WHERE name = ? LIMIT 1";
+    return !d->run(sql, {name}).empty();
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Gets the alias name from an official name.
+ *
+ * @param officialName Official name.
+ * @param tableName Table name/category. Mandatory
+ * @param source Source of the alias. Mandatory
+ * @return Alias name (or empty if not found).
+ * @throw FactoryException
+ */
+std::string
+DatabaseContext::getAliasFromOfficialName(const std::string &officialName,
+                                          const std::string &tableName,
+                                          const std::string &source) const {
+    std::string sql("SELECT auth_name, code FROM \"");
+    sql += replaceAll(tableName, "\"", "\"\"");
+    sql += "\" WHERE name = ?";
+    if (tableName == "geodetic_crs") {
+        sql += " AND type = " GEOG_2D;
+    }
+    auto res = d->run(sql, {officialName});
+    if (res.empty()) {
+        return std::string();
+    }
+    const auto &row = res.front();
+    res = d->run("SELECT alt_name FROM alias_name WHERE table_name = ? AND "
+                 "auth_name = ? AND code = ? AND source = ?",
+                 {tableName, row[0], row[1], source});
+    if (res.empty()) {
+        return std::string();
+    }
+    return res.front()[0];
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the 'text_definition' column of a table for an object
+ *
+ * @param tableName Table name/category.
+ * @param authName Authority name of the object.
+ * @param code Code of the object
+ * @return Text definition (or empty)
+ * @throw FactoryException
+ */
+std::string DatabaseContext::getTextDefinition(const std::string &tableName,
+                                               const std::string &authName,
+                                               const std::string &code) const {
+    std::string sql("SELECT text_definition FROM \"");
+    sql += replaceAll(tableName, "\"", "\"\"");
+    sql += "\" WHERE auth_name = ? AND code = ?";
+    auto res = d->run(sql, {authName, code});
+    if (res.empty()) {
+        return std::string();
+    }
+    return res.front()[0];
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the allowed authorities when researching transformations
+ * between different authorities.
+ *
+ * @throw FactoryException
+ */
+std::vector<std::string> DatabaseContext::getAllowedAuthorities(
+    const std::string &sourceAuthName,
+    const std::string &targetAuthName) const {
+    auto res = d->run(
+        "SELECT allowed_authorities FROM authority_to_authority_preference "
+        "WHERE source_auth_name = ? AND target_auth_name = ?",
+        {sourceAuthName, targetAuthName});
+    if (res.empty()) {
+        res = d->run(
+            "SELECT allowed_authorities FROM authority_to_authority_preference "
+            "WHERE source_auth_name = ? AND target_auth_name = 'any'",
+            {sourceAuthName});
+    }
+    if (res.empty()) {
+        res = d->run(
+            "SELECT allowed_authorities FROM authority_to_authority_preference "
+            "WHERE source_auth_name = 'any' AND target_auth_name = ?",
+            {targetAuthName});
+    }
+    if (res.empty()) {
+        res = d->run(
+            "SELECT allowed_authorities FROM authority_to_authority_preference "
+            "WHERE source_auth_name = 'any' AND target_auth_name = 'any'",
+            {});
+    }
+    if (res.empty()) {
+        return std::vector<std::string>();
+    }
+    return split(res.front()[0], ',');
+}
+
+// ---------------------------------------------------------------------------
+
+std::list<std::pair<std::string, std::string>>
+DatabaseContext::getNonDeprecated(const std::string &tableName,
+                                  const std::string &authName,
+                                  const std::string &code) const {
+    auto sqlRes =
+        d->run("SELECT replacement_auth_name, replacement_code, source "
+               "FROM deprecation "
+               "WHERE table_name = ? AND deprecated_auth_name = ? "
+               "AND deprecated_code = ?",
+               {tableName, authName, code});
+    std::list<std::pair<std::string, std::string>> res;
+    for (const auto &row : sqlRes) {
+        const auto &source = row[2];
+        if (source == "PROJ") {
+            const auto &replacement_auth_name = row[0];
+            const auto &replacement_code = row[1];
+            res.emplace_back(replacement_auth_name, replacement_code);
+        }
+    }
+    if (!res.empty()) {
+        return res;
+    }
+    for (const auto &row : sqlRes) {
+        const auto &replacement_auth_name = row[0];
+        const auto &replacement_code = row[1];
+        res.emplace_back(replacement_auth_name, replacement_code);
+    }
+    return res;
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct AuthorityFactory::Private {
+    Private(const DatabaseContextNNPtr &contextIn,
+            const std::string &authorityName)
+        : context_(contextIn), authority_(authorityName) {}
+
+    inline const std::string &authority() PROJ_CONST_DEFN { return authority_; }
+
+    inline const DatabaseContextNNPtr &context() PROJ_CONST_DEFN {
+        return context_;
+    }
+
+    // cppcheck-suppress functionStatic
+    void setThis(AuthorityFactoryNNPtr factory) {
+        thisFactory_ = factory.as_nullable();
+    }
+
+    // cppcheck-suppress functionStatic
+    AuthorityFactoryPtr getSharedFromThis() { return thisFactory_.lock(); }
+
+    inline AuthorityFactoryNNPtr createFactory(const std::string &auth_name) {
+        if (auth_name == authority_) {
+            return NN_NO_CHECK(thisFactory_.lock());
+        }
+        return AuthorityFactory::create(context_, auth_name);
+    }
+
+    bool rejectOpDueToMissingGrid(const operation::CoordinateOperationNNPtr &op,
+                                  bool discardIfMissingGrid);
+
+    UnitOfMeasure createUnitOfMeasure(const std::string &auth_name,
+                                      const std::string &code);
+
+    util::PropertyMap createProperties(const std::string &code,
+                                       const std::string &name, bool deprecated,
+                                       const metadata::ExtentPtr &extent);
+
+    util::PropertyMap createProperties(const std::string &code,
+                                       const std::string &name, bool deprecated,
+                                       const std::string &area_of_use_auth_name,
+                                       const std::string &area_of_use_code);
+
+    SQLResultSet run(const std::string &sql,
+                     const ListOfParams &parameters = ListOfParams());
+
+    SQLResultSet runWithCodeParam(const std::string &sql,
+                                  const std::string &code);
+
+    SQLResultSet runWithCodeParam(const char *sql, const std::string &code);
+
+    bool hasAuthorityRestriction() const {
+        return !authority_.empty() && authority_ != "any";
+    }
+
+  private:
+    DatabaseContextNNPtr context_;
+    std::string authority_;
+    std::weak_ptr<AuthorityFactory> thisFactory_{};
+};
+
+// ---------------------------------------------------------------------------
+
+SQLResultSet AuthorityFactory::Private::run(const std::string &sql,
+                                            const ListOfParams &parameters) {
+    return context()->getPrivate()->run(sql, parameters);
+}
+
+// ---------------------------------------------------------------------------
+
+SQLResultSet
+AuthorityFactory::Private::runWithCodeParam(const std::string &sql,
+                                            const std::string &code) {
+    return run(sql, {authority(), code});
+}
+
+// ---------------------------------------------------------------------------
+
+SQLResultSet
+AuthorityFactory::Private::runWithCodeParam(const char *sql,
+                                            const std::string &code) {
+    return runWithCodeParam(std::string(sql), code);
+}
+
+// ---------------------------------------------------------------------------
+
+UnitOfMeasure
+AuthorityFactory::Private::createUnitOfMeasure(const std::string &auth_name,
+                                               const std::string &code) {
+    return *(createFactory(auth_name)->createUnitOfMeasure(code));
+}
+
+// ---------------------------------------------------------------------------
+
+util::PropertyMap AuthorityFactory::Private::createProperties(
+    const std::string &code, const std::string &name, bool deprecated,
+    const metadata::ExtentPtr &extent) {
+    auto props = util::PropertyMap()
+                     .set(metadata::Identifier::CODESPACE_KEY, authority())
+                     .set(metadata::Identifier::CODE_KEY, code)
+                     .set(common::IdentifiedObject::NAME_KEY, name);
+    if (deprecated) {
+        props.set(common::IdentifiedObject::DEPRECATED_KEY, true);
+    }
+    if (extent) {
+        props.set(
+            common::ObjectUsage::DOMAIN_OF_VALIDITY_KEY,
+            NN_NO_CHECK(std::static_pointer_cast<util::BaseObject>(extent)));
+    }
+    return props;
+}
+
+// ---------------------------------------------------------------------------
+
+util::PropertyMap AuthorityFactory::Private::createProperties(
+    const std::string &code, const std::string &name, bool deprecated,
+    const std::string &area_of_use_auth_name,
+    const std::string &area_of_use_code) {
+    return createProperties(code, name, deprecated,
+                            area_of_use_auth_name.empty()
+                                ? nullptr
+                                : createFactory(area_of_use_auth_name)
+                                      ->createExtent(area_of_use_code)
+                                      .as_nullable());
+}
+
+// ---------------------------------------------------------------------------
+
+bool AuthorityFactory::Private::rejectOpDueToMissingGrid(
+    const operation::CoordinateOperationNNPtr &op, bool discardIfMissingGrid) {
+    if (discardIfMissingGrid) {
+        for (const auto &gridDesc : op->gridsNeeded(context())) {
+            if (!gridDesc.available) {
+                return true;
+            }
+        }
+    }
+    return false;
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+AuthorityFactory::~AuthorityFactory() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+AuthorityFactory::AuthorityFactory(const DatabaseContextNNPtr &context,
+                                   const std::string &authorityName)
+    : d(internal::make_unique<Private>(context, authorityName)) {}
+
+// ---------------------------------------------------------------------------
+
+// clang-format off
+/** \brief Instanciate a AuthorityFactory.
+ *
+ * The authority name might be set to the empty string in the particular case
+ * where createFromCoordinateReferenceSystemCodes(const std::string&,const std::string&,const std::string&,const std::string&) const
+ * is called.
+ *
+ * @param context Contexte.
+ * @param authorityName Authority name.
+ * @return new AuthorityFactory.
+ */
+// clang-format on
+
+AuthorityFactoryNNPtr
+AuthorityFactory::create(const DatabaseContextNNPtr &context,
+                         const std::string &authorityName) {
+
+    auto factory = AuthorityFactory::nn_make_shared<AuthorityFactory>(
+        context, authorityName);
+    factory->d->setThis(factory);
+    return factory;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns the database context. */
+const DatabaseContextNNPtr &AuthorityFactory::databaseContext() const {
+    return d->context();
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns an arbitrary object from a code.
+ *
+ * The returned object will typically be an instance of Datum,
+ * CoordinateSystem, ReferenceSystem or CoordinateOperation. If the type of
+ * the object is know at compile time, it is recommended to invoke the most
+ * precise method instead of this one (for example
+ * createCoordinateReferenceSystem(code) instead of createObject(code)
+ * if the caller know he is asking for a coordinate reference system).
+ *
+ * If there are several objects with the same code, a FactoryException is
+ * thrown.
+ *
+ * @param code Object code allocated by authority. (e.g. "4326")
+ * @return object.
+ * @throw NoSuchAuthorityCodeException
+ * @throw FactoryException
+ */
+
+util::BaseObjectNNPtr
+AuthorityFactory::createObject(const std::string &code) const {
+
+    auto res = d->runWithCodeParam(
+        "SELECT table_name FROM object_view WHERE auth_name = ? AND code = ?",
+        code);
+    if (res.empty()) {
+        throw NoSuchAuthorityCodeException("not found", d->authority(), code);
+    }
+    if (res.size() != 1) {
+        std::string msg(
+            "More than one object matching specified code. Objects found in ");
+        bool first = true;
+        for (const auto &row : res) {
+            if (!first)
+                msg += ", ";
+            msg += row[0];
+            first = false;
+        }
+        throw FactoryException(msg);
+    }
+    const auto &table_name = res.front()[0];
+    if (table_name == "area") {
+        return util::nn_static_pointer_cast<util::BaseObject>(
+            createExtent(code));
+    }
+    if (table_name == "unit_of_measure") {
+        return util::nn_static_pointer_cast<util::BaseObject>(
+            createUnitOfMeasure(code));
+    }
+    if (table_name == "prime_meridian") {
+        return util::nn_static_pointer_cast<util::BaseObject>(
+            createPrimeMeridian(code));
+    }
+    if (table_name == "ellipsoid") {
+        return util::nn_static_pointer_cast<util::BaseObject>(
+            createEllipsoid(code));
+    }
+    if (table_name == "geodetic_datum") {
+        return util::nn_static_pointer_cast<util::BaseObject>(
+            createGeodeticDatum(code));
+    }
+    if (table_name == "vertical_datum") {
+        return util::nn_static_pointer_cast<util::BaseObject>(
+            createVerticalDatum(code));
+    }
+    if (table_name == "geodetic_crs") {
+        return util::nn_static_pointer_cast<util::BaseObject>(
+            createGeodeticCRS(code));
+    }
+    if (table_name == "vertical_crs") {
+        return util::nn_static_pointer_cast<util::BaseObject>(
+            createVerticalCRS(code));
+    }
+    if (table_name == "projected_crs") {
+        return util::nn_static_pointer_cast<util::BaseObject>(
+            createProjectedCRS(code));
+    }
+    if (table_name == "compound_crs") {
+        return util::nn_static_pointer_cast<util::BaseObject>(
+            createCompoundCRS(code));
+    }
+    if (table_name == "conversion") {
+        return util::nn_static_pointer_cast<util::BaseObject>(
+            createConversion(code));
+    }
+    if (table_name == "helmert_transformation" ||
+        table_name == "grid_transformation" ||
+        table_name == "other_transformation" ||
+        table_name == "concatenated_operation") {
+        return util::nn_static_pointer_cast<util::BaseObject>(
+            createCoordinateOperation(code, false));
+    }
+    throw FactoryException("unimplemented factory for " + res.front()[0]);
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static FactoryException buildFactoryException(const char *type,
+                                              const std::string &code,
+                                              const std::exception &ex) {
+    return FactoryException(std::string("cannot build ") + type + " " + code +
+                            ": " + ex.what());
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns a metadata::Extent from the specified code.
+ *
+ * @param code Object code allocated by authority.
+ * @return object.
+ * @throw NoSuchAuthorityCodeException
+ * @throw FactoryException
+ */
+
+metadata::ExtentNNPtr
+AuthorityFactory::createExtent(const std::string &code) const {
+    const auto cacheKey(d->authority() + code);
+    {
+        auto extent = d->context()->d->getExtentFromCache(cacheKey);
+        if (extent) {
+            return NN_NO_CHECK(extent);
+        }
+    }
+    auto sql = "SELECT name, south_lat, north_lat, west_lon, east_lon, "
+               "deprecated FROM area WHERE auth_name = ? AND code = ?";
+    auto res = d->runWithCodeParam(sql, code);
+    if (res.empty()) {
+        throw NoSuchAuthorityCodeException("area not found", d->authority(),
+                                           code);
+    }
+    try {
+        const auto &row = res.front();
+        const auto &name = row[0];
+        double south_lat = c_locale_stod(row[1]);
+        double north_lat = c_locale_stod(row[2]);
+        double west_lon = c_locale_stod(row[3]);
+        double east_lon = c_locale_stod(row[4]);
+        auto bbox = metadata::GeographicBoundingBox::create(
+            west_lon, south_lat, east_lon, north_lat);
+
+        auto extent = metadata::Extent::create(
+            util::optional<std::string>(name),
+            std::vector<metadata::GeographicExtentNNPtr>{bbox},
+            std::vector<metadata::VerticalExtentNNPtr>(),
+            std::vector<metadata::TemporalExtentNNPtr>());
+        d->context()->d->cache(code, extent);
+        return extent;
+
+    } catch (const std::exception &ex) {
+        throw buildFactoryException("area", code, ex);
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns a common::UnitOfMeasure from the specified code.
+ *
+ * @param code Object code allocated by authority.
+ * @return object.
+ * @throw NoSuchAuthorityCodeException
+ * @throw FactoryException
+ */
+
+UnitOfMeasureNNPtr
+AuthorityFactory::createUnitOfMeasure(const std::string &code) const {
+    const auto cacheKey(d->authority() + code);
+    {
+        auto uom = d->context()->d->getUOMFromCache(cacheKey);
+        if (uom) {
+            return NN_NO_CHECK(uom);
+        }
+    }
+    auto res = d->runWithCodeParam(
+        "SELECT name, conv_factor, type, deprecated FROM unit_of_measure WHERE "
+        "auth_name = ? AND code = ?",
+        code);
+    if (res.empty()) {
+        throw NoSuchAuthorityCodeException("unit of measure not found",
+                                           d->authority(), code);
+    }
+    try {
+        const auto &row = res.front();
+        const auto &name =
+            (row[0] == "degree (supplier to define representation)")
+                ? UnitOfMeasure::DEGREE.name()
+                : row[0];
+        double conv_factor = (code == "9107" || code == "9108")
+                                 ? UnitOfMeasure::DEGREE.conversionToSI()
+                                 : c_locale_stod(row[1]);
+        constexpr double EPS = 1e-10;
+        if (std::fabs(conv_factor - UnitOfMeasure::DEGREE.conversionToSI()) <
+            EPS * UnitOfMeasure::DEGREE.conversionToSI()) {
+            conv_factor = UnitOfMeasure::DEGREE.conversionToSI();
+        }
+        if (std::fabs(conv_factor -
+                      UnitOfMeasure::ARC_SECOND.conversionToSI()) <
+            EPS * UnitOfMeasure::ARC_SECOND.conversionToSI()) {
+            conv_factor = UnitOfMeasure::ARC_SECOND.conversionToSI();
+        }
+        const auto &type_str = row[2];
+        UnitOfMeasure::Type unitType = UnitOfMeasure::Type::UNKNOWN;
+        if (type_str == "length")
+            unitType = UnitOfMeasure::Type::LINEAR;
+        else if (type_str == "angle")
+            unitType = UnitOfMeasure::Type::ANGULAR;
+        else if (type_str == "scale")
+            unitType = UnitOfMeasure::Type::SCALE;
+        else if (type_str == "time")
+            unitType = UnitOfMeasure::Type::TIME;
+        auto uom = util::nn_make_shared<UnitOfMeasure>(
+            name, conv_factor, unitType, d->authority(), code);
+        d->context()->d->cache(cacheKey, uom);
+        return uom;
+    } catch (const std::exception &ex) {
+        throw buildFactoryException("unit of measure", code, ex);
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static double normalizeMeasure(const std::string &uom_code,
+                               const std::string &value,
+                               std::string &normalized_uom_code) {
+    if (uom_code == "9110") // DDD.MMSSsss.....
+    {
+        double normalized_value = c_locale_stod(value);
+        std::ostringstream buffer;
+        buffer.imbue(std::locale::classic());
+        constexpr size_t precision = 12;
+        buffer << std::fixed << std::setprecision(precision)
+               << normalized_value;
+        auto formatted = buffer.str();
+        size_t dotPos = formatted.find('.');
+        assert(dotPos + 1 + precision == formatted.size());
+        auto minutes = formatted.substr(dotPos + 1, 2);
+        auto seconds = formatted.substr(dotPos + 3);
+        assert(seconds.size() == precision - 2);
+        normalized_value =
+            (normalized_value < 0 ? -1.0 : 1.0) *
+            (int(std::fabs(normalized_value)) + c_locale_stod(minutes) / 60. +
+             (c_locale_stod(seconds) / std::pow(10, seconds.size() - 2)) /
+                 3600.);
+        normalized_uom_code = common::UnitOfMeasure::DEGREE.code();
+        return normalized_value;
+    } else {
+        normalized_uom_code = uom_code;
+        return c_locale_stod(value);
+    }
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns a datum::PrimeMeridian from the specified code.
+ *
+ * @param code Object code allocated by authority.
+ * @return object.
+ * @throw NoSuchAuthorityCodeException
+ * @throw FactoryException
+ */
+
+datum::PrimeMeridianNNPtr
+AuthorityFactory::createPrimeMeridian(const std::string &code) const {
+    const auto cacheKey(d->authority() + code);
+    {
+        auto pm = d->context()->d->getPrimeMeridianFromCache(cacheKey);
+        if (pm) {
+            return NN_NO_CHECK(pm);
+        }
+    }
+    auto res = d->runWithCodeParam(
+        "SELECT name, longitude, uom_auth_name, uom_code, deprecated FROM "
+        "prime_meridian WHERE "
+        "auth_name = ? AND code = ?",
+        code);
+    if (res.empty()) {
+        throw NoSuchAuthorityCodeException("prime meridian not found",
+                                           d->authority(), code);
+    }
+    try {
+        const auto &row = res.front();
+        const auto &name = row[0];
+        const auto &longitude = row[1];
+        const auto &uom_auth_name = row[2];
+        const auto &uom_code = row[3];
+        const bool deprecated = row[4] == "1";
+
+        std::string normalized_uom_code(uom_code);
+        const double normalized_value =
+            normalizeMeasure(uom_code, longitude, normalized_uom_code);
+
+        auto uom = d->createUnitOfMeasure(uom_auth_name, normalized_uom_code);
+        auto props = d->createProperties(code, name, deprecated, nullptr);
+        auto pm = datum::PrimeMeridian::create(
+            props, common::Angle(normalized_value, uom));
+        d->context()->d->cache(cacheKey, pm);
+        return pm;
+    } catch (const std::exception &ex) {
+        throw buildFactoryException("prime meridian", code, ex);
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Identify a celestial body from an approximate radius.
+ *
+ * @param semi_major_axis Approximate semi-major axis.
+ * @param tolerance Relative error allowed.
+ * @return celestial body name if one single match found.
+ * @throw FactoryException
+ */
+
+std::string
+AuthorityFactory::identifyBodyFromSemiMajorAxis(double semi_major_axis,
+                                                double tolerance) const {
+    auto res =
+        d->run("SELECT name, (ABS(semi_major_axis - ?) / semi_major_axis ) "
+               "AS rel_error FROM celestial_body WHERE rel_error <= ?",
+               {semi_major_axis, tolerance});
+    if (res.empty()) {
+        throw FactoryException("no match found");
+    }
+    if (res.size() > 1) {
+        throw FactoryException("more than one match found");
+    }
+    return res.front()[0];
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns a datum::Ellipsoid from the specified code.
+ *
+ * @param code Object code allocated by authority.
+ * @return object.
+ * @throw NoSuchAuthorityCodeException
+ * @throw FactoryException
+ */
+
+datum::EllipsoidNNPtr
+AuthorityFactory::createEllipsoid(const std::string &code) const {
+    auto res = d->runWithCodeParam(
+        "SELECT ellipsoid.name, ellipsoid.semi_major_axis, "
+        "ellipsoid.uom_auth_name, ellipsoid.uom_code, "
+        "ellipsoid.inv_flattening, ellipsoid.semi_minor_axis, "
+        "celestial_body.name AS body_name, ellipsoid.deprecated FROM "
+        "ellipsoid JOIN celestial_body "
+        "ON ellipsoid.celestial_body_auth_name = celestial_body.auth_name AND "
+        "ellipsoid.celestial_body_code = celestial_body.code WHERE "
+        "ellipsoid.auth_name = ? AND ellipsoid.code = ?",
+        code);
+    if (res.empty()) {
+        throw NoSuchAuthorityCodeException("ellipsoid not found",
+                                           d->authority(), code);
+    }
+    try {
+        const auto &row = res.front();
+        const auto &name = row[0];
+        const auto &semi_major_axis_str = row[1];
+        double semi_major_axis = c_locale_stod(semi_major_axis_str);
+        const auto &uom_auth_name = row[2];
+        const auto &uom_code = row[3];
+        const auto &inv_flattening_str = row[4];
+        const auto &semi_minor_axis_str = row[5];
+        const auto &body = row[6];
+        const bool deprecated = row[7] == "1";
+        auto uom = d->createUnitOfMeasure(uom_auth_name, uom_code);
+        auto props = d->createProperties(code, name, deprecated, nullptr);
+        if (!inv_flattening_str.empty()) {
+            return datum::Ellipsoid::createFlattenedSphere(
+                props, common::Length(semi_major_axis, uom),
+                common::Scale(c_locale_stod(inv_flattening_str)), body);
+        } else if (semi_major_axis_str == semi_minor_axis_str) {
+            return datum::Ellipsoid::createSphere(
+                props, common::Length(semi_major_axis, uom), body);
+        } else {
+            return datum::Ellipsoid::createTwoAxis(
+                props, common::Length(semi_major_axis, uom),
+                common::Length(c_locale_stod(semi_minor_axis_str), uom), body);
+        }
+    } catch (const std::exception &ex) {
+        throw buildFactoryException("elllipsoid", code, ex);
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns a datum::GeodeticReferenceFrame from the specified code.
+ *
+ * @param code Object code allocated by authority.
+ * @return object.
+ * @throw NoSuchAuthorityCodeException
+ * @throw FactoryException
+ */
+
+datum::GeodeticReferenceFrameNNPtr
+AuthorityFactory::createGeodeticDatum(const std::string &code) const {
+    const auto cacheKey(d->authority() + code);
+    {
+        auto datum = d->context()->d->getGeodeticDatumFromCache(cacheKey);
+        if (datum) {
+            return NN_NO_CHECK(datum);
+        }
+    }
+    auto res = d->runWithCodeParam(
+        "SELECT name, ellipsoid_auth_name, ellipsoid_code, "
+        "prime_meridian_auth_name, prime_meridian_code, area_of_use_auth_name, "
+        "area_of_use_code, deprecated FROM geodetic_datum WHERE "
+        "auth_name = ? AND code = ?",
+        code);
+    if (res.empty()) {
+        throw NoSuchAuthorityCodeException("geodetic datum not found",
+                                           d->authority(), code);
+    }
+    try {
+        const auto &row = res.front();
+        const auto &name = row[0];
+        const auto &ellipsoid_auth_name = row[1];
+        const auto &ellipsoid_code = row[2];
+        const auto &prime_meridian_auth_name = row[3];
+        const auto &prime_meridian_code = row[4];
+        const auto &area_of_use_auth_name = row[5];
+        const auto &area_of_use_code = row[6];
+        const bool deprecated = row[7] == "1";
+        auto ellipsoid = d->createFactory(ellipsoid_auth_name)
+                             ->createEllipsoid(ellipsoid_code);
+        auto pm = d->createFactory(prime_meridian_auth_name)
+                      ->createPrimeMeridian(prime_meridian_code);
+        auto props = d->createProperties(
+            code, name, deprecated, area_of_use_auth_name, area_of_use_code);
+        auto anchor = util::optional<std::string>();
+        auto datum =
+            datum::GeodeticReferenceFrame::create(props, ellipsoid, anchor, pm);
+        d->context()->d->cache(cacheKey, datum);
+        return datum;
+    } catch (const std::exception &ex) {
+        throw buildFactoryException("geodetic reference frame", code, ex);
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns a datum::VerticalReferenceFrame from the specified code.
+ *
+ * @param code Object code allocated by authority.
+ * @return object.
+ * @throw NoSuchAuthorityCodeException
+ * @throw FactoryException
+ */
+
+datum::VerticalReferenceFrameNNPtr
+AuthorityFactory::createVerticalDatum(const std::string &code) const {
+    auto res = d->runWithCodeParam(
+        "SELECT name, area_of_use_auth_name, area_of_use_code, deprecated FROM "
+        "vertical_datum WHERE auth_name = ? AND code = ?",
+        code);
+    if (res.empty()) {
+        throw NoSuchAuthorityCodeException("vertical datum not found",
+                                           d->authority(), code);
+    }
+    try {
+        const auto &row = res.front();
+        const auto &name = row[0];
+        const auto &area_of_use_auth_name = row[1];
+        const auto &area_of_use_code = row[2];
+        const bool deprecated = row[3] == "1";
+        auto props = d->createProperties(
+            code, name, deprecated, area_of_use_auth_name, area_of_use_code);
+        auto anchor = util::optional<std::string>();
+        return datum::VerticalReferenceFrame::create(props, anchor);
+    } catch (const std::exception &ex) {
+        throw buildFactoryException("vertical reference frame", code, ex);
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns a datum::Datum from the specified code.
+ *
+ * @param code Object code allocated by authority.
+ * @return object.
+ * @throw NoSuchAuthorityCodeException
+ * @throw FactoryException
+ */
+
+datum::DatumNNPtr AuthorityFactory::createDatum(const std::string &code) const {
+    auto res =
+        d->run("SELECT 'geodetic_datum' FROM geodetic_datum WHERE "
+               "auth_name = ? AND code = ? "
+               "UNION ALL SELECT 'vertical_datum' FROM vertical_datum WHERE "
+               "auth_name = ? AND code = ?",
+               {d->authority(), code, d->authority(), code});
+    if (res.empty()) {
+        throw NoSuchAuthorityCodeException("datum not found", d->authority(),
+                                           code);
+    }
+    if (res.front()[0] == "geodetic_datum") {
+        return createGeodeticDatum(code);
+    }
+    return createVerticalDatum(code);
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static cs::MeridianPtr createMeridian(const std::string &val) {
+    try {
+        const std::string degW(std::string("\xC2\xB0") + "W");
+        if (ends_with(val, degW)) {
+            return cs::Meridian::create(common::Angle(
+                -c_locale_stod(val.substr(0, val.size() - degW.size()))));
+        }
+        const std::string degE(std::string("\xC2\xB0") + "E");
+        if (ends_with(val, degE)) {
+            return cs::Meridian::create(common::Angle(
+                c_locale_stod(val.substr(0, val.size() - degE.size()))));
+        }
+    } catch (const std::exception &) {
+    }
+    return nullptr;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns a cs::CoordinateSystem from the specified code.
+ *
+ * @param code Object code allocated by authority.
+ * @return object.
+ * @throw NoSuchAuthorityCodeException
+ * @throw FactoryException
+ */
+
+cs::CoordinateSystemNNPtr
+AuthorityFactory::createCoordinateSystem(const std::string &code) const {
+    const auto cacheKey(d->authority() + code);
+    {
+        auto cs = d->context()->d->getCoordinateSystemFromCache(cacheKey);
+        if (cs) {
+            return NN_NO_CHECK(cs);
+        }
+    }
+    auto res = d->runWithCodeParam(
+        "SELECT axis.name, abbrev, orientation, uom_auth_name, uom_code, "
+        "cs.type FROM "
+        "axis LEFT JOIN coordinate_system cs ON "
+        "axis.coordinate_system_auth_name = cs.auth_name AND "
+        "axis.coordinate_system_code = cs.code WHERE "
+        "coordinate_system_auth_name = ? AND coordinate_system_code = ? ORDER "
+        "BY coordinate_system_order",
+        code);
+    if (res.empty()) {
+        throw NoSuchAuthorityCodeException("coordinate system not found",
+                                           d->authority(), code);
+    }
+
+    const auto &csType = res.front()[5];
+    std::vector<cs::CoordinateSystemAxisNNPtr> axisList;
+    for (const auto &row : res) {
+        const auto &name = row[0];
+        const auto &abbrev = row[1];
+        const auto &orientation = row[2];
+        const auto &uom_auth_name = row[3];
+        const auto &uom_code = row[4];
+        auto uom = d->createUnitOfMeasure(uom_auth_name, uom_code);
+        auto props =
+            util::PropertyMap().set(common::IdentifiedObject::NAME_KEY, name);
+        const cs::AxisDirection *direction =
+            cs::AxisDirection::valueOf(orientation);
+        cs::MeridianPtr meridian;
+        if (direction == nullptr) {
+            if (orientation == "Geocentre > equator/0"
+                               "\xC2\xB0"
+                               "E") {
+                direction = &(cs::AxisDirection::GEOCENTRIC_X);
+            } else if (orientation == "Geocentre > equator/90"
+                                      "\xC2\xB0"
+                                      "E") {
+                direction = &(cs::AxisDirection::GEOCENTRIC_Y);
+            } else if (orientation == "Geocentre > north pole") {
+                direction = &(cs::AxisDirection::GEOCENTRIC_Z);
+            } else if (starts_with(orientation, "North along ")) {
+                direction = &(cs::AxisDirection::NORTH);
+                meridian =
+                    createMeridian(orientation.substr(strlen("North along ")));
+            } else if (starts_with(orientation, "South along ")) {
+                direction = &(cs::AxisDirection::SOUTH);
+                meridian =
+                    createMeridian(orientation.substr(strlen("South along ")));
+            } else {
+                throw FactoryException("unknown axis direction: " +
+                                       orientation);
+            }
+        }
+        axisList.emplace_back(cs::CoordinateSystemAxis::create(
+            props, abbrev, *direction, uom, meridian));
+    }
+
+    const auto cacheAndRet = [this,
+                              &cacheKey](const cs::CoordinateSystemNNPtr &cs) {
+        d->context()->d->cache(cacheKey, cs);
+        return cs;
+    };
+
+    auto props = util::PropertyMap()
+                     .set(metadata::Identifier::CODESPACE_KEY, d->authority())
+                     .set(metadata::Identifier::CODE_KEY, code);
+    if (csType == "ellipsoidal") {
+        if (axisList.size() == 2) {
+            return cacheAndRet(
+                cs::EllipsoidalCS::create(props, axisList[0], axisList[1]));
+        }
+        if (axisList.size() == 3) {
+            return cacheAndRet(cs::EllipsoidalCS::create(
+                props, axisList[0], axisList[1], axisList[2]));
+        }
+        throw FactoryException("invalid number of axis for EllipsoidalCS");
+    }
+    if (csType == "Cartesian") {
+        if (axisList.size() == 2) {
+            return cacheAndRet(
+                cs::CartesianCS::create(props, axisList[0], axisList[1]));
+        }
+        if (axisList.size() == 3) {
+            return cacheAndRet(cs::CartesianCS::create(
+                props, axisList[0], axisList[1], axisList[2]));
+        }
+        throw FactoryException("invalid number of axis for CartesianCS");
+    }
+    if (csType == "vertical") {
+        if (axisList.size() == 1) {
+            return cacheAndRet(cs::VerticalCS::create(props, axisList[0]));
+        }
+        throw FactoryException("invalid number of axis for VerticalCS");
+    }
+    throw FactoryException("unhandled coordinate system type: " + csType);
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns a crs::GeodeticCRS from the specified code.
+ *
+ * @param code Object code allocated by authority.
+ * @return object.
+ * @throw NoSuchAuthorityCodeException
+ * @throw FactoryException
+ */
+
+crs::GeodeticCRSNNPtr
+AuthorityFactory::createGeodeticCRS(const std::string &code) const {
+    return createGeodeticCRS(code, false);
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns a crs::GeographicCRS from the specified code.
+ *
+ * @param code Object code allocated by authority.
+ * @return object.
+ * @throw NoSuchAuthorityCodeException
+ * @throw FactoryException
+ */
+
+crs::GeographicCRSNNPtr
+AuthorityFactory::createGeographicCRS(const std::string &code) const {
+    return NN_NO_CHECK(util::nn_dynamic_pointer_cast<crs::GeographicCRS>(
+        createGeodeticCRS(code, true)));
+}
+
+// ---------------------------------------------------------------------------
+
+static crs::GeodeticCRSNNPtr
+cloneWithProps(const crs::GeodeticCRSNNPtr &geodCRS,
+               const util::PropertyMap &props) {
+    auto cs = geodCRS->coordinateSystem();
+    auto datum = geodCRS->datum();
+    if (!datum) {
+        return geodCRS;
+    }
+    auto ellipsoidalCS = util::nn_dynamic_pointer_cast<cs::EllipsoidalCS>(cs);
+    if (ellipsoidalCS) {
+        return crs::GeographicCRS::create(props, NN_NO_CHECK(datum),
+                                          NN_NO_CHECK(ellipsoidalCS));
+    }
+    auto geocentricCS = util::nn_dynamic_pointer_cast<cs::CartesianCS>(cs);
+    if (geocentricCS) {
+        return crs::GeodeticCRS::create(props, NN_NO_CHECK(datum),
+                                        NN_NO_CHECK(geocentricCS));
+    }
+    return geodCRS;
+}
+
+// ---------------------------------------------------------------------------
+
+crs::GeodeticCRSNNPtr
+AuthorityFactory::createGeodeticCRS(const std::string &code,
+                                    bool geographicOnly) const {
+    const auto cacheKey(d->authority() + code);
+    auto crs = std::dynamic_pointer_cast<crs::GeodeticCRS>(
+        d->context()->d->getCRSFromCache(cacheKey));
+    if (crs) {
+        return NN_NO_CHECK(crs);
+    }
+    std::string sql("SELECT name, type, coordinate_system_auth_name, "
+                    "coordinate_system_code, datum_auth_name, datum_code, "
+                    "area_of_use_auth_name, area_of_use_code, text_definition, "
+                    "deprecated FROM "
+                    "geodetic_crs WHERE auth_name = ? AND code = ?");
+    if (geographicOnly) {
+        sql += " AND type in (" GEOG_2D "," GEOG_3D ")";
+    }
+    auto res = d->runWithCodeParam(sql, code);
+    if (res.empty()) {
+        throw NoSuchAuthorityCodeException("geodeticCRS not found",
+                                           d->authority(), code);
+    }
+    try {
+        const auto &row = res.front();
+        const auto &name = row[0];
+        const auto &type = row[1];
+        const auto &cs_auth_name = row[2];
+        const auto &cs_code = row[3];
+        const auto &datum_auth_name = row[4];
+        const auto &datum_code = row[5];
+        const auto &area_of_use_auth_name = row[6];
+        const auto &area_of_use_code = row[7];
+        const auto &text_definition = row[8];
+        const bool deprecated = row[9] == "1";
+
+        auto props = d->createProperties(
+            code, name, deprecated, area_of_use_auth_name, area_of_use_code);
+
+        if (!text_definition.empty()) {
+            DatabaseContext::Private::RecursionDetector detector(d->context());
+            auto obj = createFromUserInput(text_definition, d->context());
+            auto geodCRS = util::nn_dynamic_pointer_cast<crs::GeodeticCRS>(obj);
+            if (geodCRS) {
+                return cloneWithProps(NN_NO_CHECK(geodCRS), props);
+            }
+
+            auto boundCRS = dynamic_cast<const crs::BoundCRS *>(obj.get());
+            if (boundCRS) {
+                geodCRS = util::nn_dynamic_pointer_cast<crs::GeodeticCRS>(
+                    boundCRS->baseCRS());
+                if (geodCRS) {
+                    auto newBoundCRS = crs::BoundCRS::create(
+                        cloneWithProps(NN_NO_CHECK(geodCRS), props),
+                        boundCRS->hubCRS(), boundCRS->transformation());
+                    return NN_NO_CHECK(
+                        util::nn_dynamic_pointer_cast<crs::GeodeticCRS>(
+                            newBoundCRS->baseCRSWithCanonicalBoundCRS()));
+                }
+            }
+
+            throw FactoryException(
+                "text_definition does not define a GeodeticCRS");
+        }
+
+        auto cs =
+            d->createFactory(cs_auth_name)->createCoordinateSystem(cs_code);
+        auto datum =
+            d->createFactory(datum_auth_name)->createGeodeticDatum(datum_code);
+
+        auto ellipsoidalCS =
+            util::nn_dynamic_pointer_cast<cs::EllipsoidalCS>(cs);
+        if ((type == "geographic 2D" || type == "geographic 3D") &&
+            ellipsoidalCS) {
+            auto crsRet = crs::GeographicCRS::create(
+                props, datum, NN_NO_CHECK(ellipsoidalCS));
+            d->context()->d->cache(cacheKey, crsRet);
+            return crsRet;
+        }
+        auto geocentricCS = util::nn_dynamic_pointer_cast<cs::CartesianCS>(cs);
+        if (type == "geocentric" && geocentricCS) {
+            auto crsRet = crs::GeodeticCRS::create(props, datum,
+                                                   NN_NO_CHECK(geocentricCS));
+            d->context()->d->cache(cacheKey, crsRet);
+            return crsRet;
+        }
+        throw FactoryException("unsupported (type, CS type) for geodeticCRS: " +
+                               type + ", " + cs->getWKT2Type(true));
+    } catch (const std::exception &ex) {
+        throw buildFactoryException("geodeticCRS", code, ex);
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns a crs::VerticalCRS from the specified code.
+ *
+ * @param code Object code allocated by authority.
+ * @return object.
+ * @throw NoSuchAuthorityCodeException
+ * @throw FactoryException
+ */
+
+crs::VerticalCRSNNPtr
+AuthorityFactory::createVerticalCRS(const std::string &code) const {
+    auto res = d->runWithCodeParam(
+        "SELECT name, coordinate_system_auth_name, "
+        "coordinate_system_code, datum_auth_name, datum_code, "
+        "area_of_use_auth_name, area_of_use_code, deprecated FROM "
+        "vertical_crs WHERE auth_name = ? AND code = ?",
+        code);
+    if (res.empty()) {
+        throw NoSuchAuthorityCodeException("verticalCRS not found",
+                                           d->authority(), code);
+    }
+    try {
+        const auto &row = res.front();
+        const auto &name = row[0];
+        const auto &cs_auth_name = row[1];
+        const auto &cs_code = row[2];
+        const auto &datum_auth_name = row[3];
+        const auto &datum_code = row[4];
+        const auto &area_of_use_auth_name = row[5];
+        const auto &area_of_use_code = row[6];
+        const bool deprecated = row[7] == "1";
+        auto cs =
+            d->createFactory(cs_auth_name)->createCoordinateSystem(cs_code);
+        auto datum =
+            d->createFactory(datum_auth_name)->createVerticalDatum(datum_code);
+
+        auto props = d->createProperties(
+            code, name, deprecated, area_of_use_auth_name, area_of_use_code);
+
+        auto verticalCS = util::nn_dynamic_pointer_cast<cs::VerticalCS>(cs);
+        if (verticalCS) {
+            return crs::VerticalCRS::create(props, datum,
+                                            NN_NO_CHECK(verticalCS));
+        }
+        throw FactoryException("unsupported CS type for verticalCRS: " +
+                               cs->getWKT2Type(true));
+    } catch (const std::exception &ex) {
+        throw buildFactoryException("verticalCRS", code, ex);
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns a operation::Conversion from the specified code.
+ *
+ * @param code Object code allocated by authority.
+ * @return object.
+ * @throw NoSuchAuthorityCodeException
+ * @throw FactoryException
+ */
+
+operation::ConversionNNPtr
+AuthorityFactory::createConversion(const std::string &code) const {
+
+    static const char *sql =
+        "SELECT name, area_of_use_auth_name, area_of_use_code, "
+        "method_auth_name, method_code, method_name, "
+
+        "param1_auth_name, param1_code, param1_name, param1_value, "
+        "param1_uom_auth_name, param1_uom_code, "
+
+        "param2_auth_name, param2_code, param2_name, param2_value, "
+        "param2_uom_auth_name, param2_uom_code, "
+
+        "param3_auth_name, param3_code, param3_name, param3_value, "
+        "param3_uom_auth_name, param3_uom_code, "
+
+        "param4_auth_name, param4_code, param4_name, param4_value, "
+        "param4_uom_auth_name, param4_uom_code, "
+
+        "param5_auth_name, param5_code, param5_name, param5_value, "
+        "param5_uom_auth_name, param5_uom_code, "
+
+        "param6_auth_name, param6_code, param6_name, param6_value, "
+        "param6_uom_auth_name, param6_uom_code, "
+
+        "param7_auth_name, param7_code, param7_name, param7_value, "
+        "param7_uom_auth_name, param7_uom_code, "
+
+        "deprecated FROM conversion WHERE auth_name = ? AND code = ?";
+
+    auto res = d->runWithCodeParam(sql, code);
+    if (res.empty()) {
+        throw NoSuchAuthorityCodeException("conversion not found",
+                                           d->authority(), code);
+    }
+    try {
+        const auto &row = res.front();
+        size_t idx = 0;
+        const auto &name = row[idx++];
+        const auto &area_of_use_auth_name = row[idx++];
+        const auto &area_of_use_code = row[idx++];
+        const auto &method_auth_name = row[idx++];
+        const auto &method_code = row[idx++];
+        const auto &method_name = row[idx++];
+        const size_t base_param_idx = idx;
+        std::vector<operation::OperationParameterNNPtr> parameters;
+        std::vector<operation::ParameterValueNNPtr> values;
+        constexpr int N_MAX_PARAMS = 7;
+        for (int i = 0; i < N_MAX_PARAMS; ++i) {
+            const auto &param_auth_name = row[base_param_idx + i * 6 + 0];
+            if (param_auth_name.empty()) {
+                break;
+            }
+            const auto &param_code = row[base_param_idx + i * 6 + 1];
+            const auto &param_name = row[base_param_idx + i * 6 + 2];
+            const auto &param_value = row[base_param_idx + i * 6 + 3];
+            const auto &param_uom_auth_name = row[base_param_idx + i * 6 + 4];
+            const auto &param_uom_code = row[base_param_idx + i * 6 + 5];
+            parameters.emplace_back(operation::OperationParameter::create(
+                util::PropertyMap()
+                    .set(metadata::Identifier::CODESPACE_KEY, param_auth_name)
+                    .set(metadata::Identifier::CODE_KEY, param_code)
+                    .set(common::IdentifiedObject::NAME_KEY, param_name)));
+            std::string normalized_uom_code(param_uom_code);
+            const double normalized_value = normalizeMeasure(
+                param_uom_code, param_value, normalized_uom_code);
+            auto uom = d->createUnitOfMeasure(param_uom_auth_name,
+                                              normalized_uom_code);
+            values.emplace_back(operation::ParameterValue::create(
+                common::Measure(normalized_value, uom)));
+        }
+        const bool deprecated = row[base_param_idx + N_MAX_PARAMS * 6] == "1";
+
+        auto propConversion = d->createProperties(
+            code, name, deprecated, area_of_use_auth_name, area_of_use_code);
+
+        auto propMethod = util::PropertyMap().set(
+            common::IdentifiedObject::NAME_KEY, method_name);
+        if (!method_auth_name.empty()) {
+            propMethod
+                .set(metadata::Identifier::CODESPACE_KEY, method_auth_name)
+                .set(metadata::Identifier::CODE_KEY, method_code);
+        }
+
+        return operation::Conversion::create(propConversion, propMethod,
+                                             parameters, values);
+    } catch (const std::exception &ex) {
+        throw buildFactoryException("conversion", code, ex);
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns a crs::ProjectedCRS from the specified code.
+ *
+ * @param code Object code allocated by authority.
+ * @return object.
+ * @throw NoSuchAuthorityCodeException
+ * @throw FactoryException
+ */
+
+crs::ProjectedCRSNNPtr
+AuthorityFactory::createProjectedCRS(const std::string &code) const {
+    auto res = d->runWithCodeParam(
+        "SELECT name, coordinate_system_auth_name, "
+        "coordinate_system_code, geodetic_crs_auth_name, geodetic_crs_code, "
+        "conversion_auth_name, conversion_code, "
+        "area_of_use_auth_name, area_of_use_code, text_definition, "
+        "deprecated FROM projected_crs WHERE auth_name = ? AND code = ?",
+        code);
+    if (res.empty()) {
+        throw NoSuchAuthorityCodeException("projectedCRS not found",
+                                           d->authority(), code);
+    }
+    try {
+        const auto &row = res.front();
+        const auto &name = row[0];
+        const auto &cs_auth_name = row[1];
+        const auto &cs_code = row[2];
+        const auto &geodetic_crs_auth_name = row[3];
+        const auto &geodetic_crs_code = row[4];
+        const auto &conversion_auth_name = row[5];
+        const auto &conversion_code = row[6];
+        const auto &area_of_use_auth_name = row[7];
+        const auto &area_of_use_code = row[8];
+        const auto &text_definition = row[9];
+        const bool deprecated = row[10] == "1";
+
+        auto props = d->createProperties(
+            code, name, deprecated, area_of_use_auth_name, area_of_use_code);
+
+        if (!text_definition.empty()) {
+            DatabaseContext::Private::RecursionDetector detector(d->context());
+            auto obj = createFromUserInput(text_definition, d->context());
+            auto projCRS = dynamic_cast<const crs::ProjectedCRS *>(obj.get());
+            if (projCRS) {
+                const auto &conv = projCRS->derivingConversionRef();
+                auto newConv =
+                    (conv->nameStr() == "unnamed")
+                        ? operation::Conversion::create(
+                              util::PropertyMap().set(
+                                  common::IdentifiedObject::NAME_KEY, name),
+                              conv->method(), conv->parameterValues())
+                        : conv;
+                return crs::ProjectedCRS::create(props, projCRS->baseCRS(),
+                                                 newConv,
+                                                 projCRS->coordinateSystem());
+            }
+
+            auto boundCRS = dynamic_cast<const crs::BoundCRS *>(obj.get());
+            if (boundCRS) {
+                projCRS = dynamic_cast<const crs::ProjectedCRS *>(
+                    boundCRS->baseCRS().get());
+                if (projCRS) {
+                    auto newBoundCRS = crs::BoundCRS::create(
+                        crs::ProjectedCRS::create(
+                            props, projCRS->baseCRS(),
+                            projCRS->derivingConversionRef(),
+                            projCRS->coordinateSystem()),
+                        boundCRS->hubCRS(), boundCRS->transformation());
+                    return NN_NO_CHECK(
+                        util::nn_dynamic_pointer_cast<crs::ProjectedCRS>(
+                            newBoundCRS->baseCRSWithCanonicalBoundCRS()));
+                }
+            }
+
+            throw FactoryException(
+                "text_definition does not define a ProjectedCRS");
+        }
+
+        auto cs =
+            d->createFactory(cs_auth_name)->createCoordinateSystem(cs_code);
+
+        auto baseCRS = d->createFactory(geodetic_crs_auth_name)
+                           ->createGeodeticCRS(geodetic_crs_code);
+
+        auto conv = d->createFactory(conversion_auth_name)
+                        ->createConversion(conversion_code);
+
+        auto cartesianCS = util::nn_dynamic_pointer_cast<cs::CartesianCS>(cs);
+        if (cartesianCS) {
+            return crs::ProjectedCRS::create(props, baseCRS, conv,
+                                             NN_NO_CHECK(cartesianCS));
+        }
+        throw FactoryException("unsupported CS type for projectedCRS: " +
+                               cs->getWKT2Type(true));
+    } catch (const std::exception &ex) {
+        throw buildFactoryException("projectedCRS", code, ex);
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns a crs::CompoundCRS from the specified code.
+ *
+ * @param code Object code allocated by authority.
+ * @return object.
+ * @throw NoSuchAuthorityCodeException
+ * @throw FactoryException
+ */
+
+crs::CompoundCRSNNPtr
+AuthorityFactory::createCompoundCRS(const std::string &code) const {
+    auto res = d->runWithCodeParam(
+        "SELECT name, horiz_crs_auth_name, horiz_crs_code, "
+        "vertical_crs_auth_name, vertical_crs_code, "
+        "area_of_use_auth_name, area_of_use_code, deprecated FROM "
+        "compound_crs WHERE auth_name = ? AND code = ?",
+        code);
+    if (res.empty()) {
+        throw NoSuchAuthorityCodeException("compoundCRS not found",
+                                           d->authority(), code);
+    }
+    try {
+        const auto &row = res.front();
+        const auto &name = row[0];
+        const auto &horiz_crs_auth_name = row[1];
+        const auto &horiz_crs_code = row[2];
+        const auto &vertical_crs_auth_name = row[3];
+        const auto &vertical_crs_code = row[4];
+        const auto &area_of_use_auth_name = row[5];
+        const auto &area_of_use_code = row[6];
+        const bool deprecated = row[7] == "1";
+
+        auto horizCRS =
+            d->createFactory(horiz_crs_auth_name)
+                ->createCoordinateReferenceSystem(horiz_crs_code, false);
+        auto vertCRS = d->createFactory(vertical_crs_auth_name)
+                           ->createVerticalCRS(vertical_crs_code);
+
+        auto props = d->createProperties(
+            code, name, deprecated, area_of_use_auth_name, area_of_use_code);
+        return crs::CompoundCRS::create(
+            props, std::vector<crs::CRSNNPtr>{horizCRS, vertCRS});
+    } catch (const std::exception &ex) {
+        throw buildFactoryException("compoundCRS", code, ex);
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns a crs::CRS from the specified code.
+ *
+ * @param code Object code allocated by authority.
+ * @return object.
+ * @throw NoSuchAuthorityCodeException
+ * @throw FactoryException
+ */
+
+crs::CRSNNPtr AuthorityFactory::createCoordinateReferenceSystem(
+    const std::string &code) const {
+    return createCoordinateReferenceSystem(code, true);
+}
+
+crs::CRSNNPtr
+AuthorityFactory::createCoordinateReferenceSystem(const std::string &code,
+                                                  bool allowCompound) const {
+    const auto cacheKey(d->authority() + code);
+    auto crs = d->context()->d->getCRSFromCache(cacheKey);
+    if (crs) {
+        return NN_NO_CHECK(crs);
+    }
+    auto res = d->runWithCodeParam(
+        "SELECT type FROM crs_view WHERE auth_name = ? AND code = ?", code);
+    if (res.empty()) {
+        throw NoSuchAuthorityCodeException("crs not found", d->authority(),
+                                           code);
+    }
+    const auto &type = res.front()[0];
+    if (type == "geographic 2D" || type == "geographic 3D" ||
+        type == "geocentric") {
+        return createGeodeticCRS(code);
+    }
+    if (type == "vertical") {
+        return createVerticalCRS(code);
+    }
+    if (type == "projected") {
+        return createProjectedCRS(code);
+    }
+    if (allowCompound && type == "compound") {
+        return createCompoundCRS(code);
+    }
+    throw FactoryException("unhandled CRS type: " + type);
+}
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+static util::PropertyMap createMapNameEPSGCode(const std::string &name,
+                                               int code) {
+    return util::PropertyMap()
+        .set(common::IdentifiedObject::NAME_KEY, name)
+        .set(metadata::Identifier::CODESPACE_KEY, metadata::Identifier::EPSG)
+        .set(metadata::Identifier::CODE_KEY, code);
+}
+
+// ---------------------------------------------------------------------------
+
+static operation::OperationParameterNNPtr createOpParamNameEPSGCode(int code) {
+    const char *name = operation::OperationParameter::getNameForEPSGCode(code);
+    assert(name);
+    return operation::OperationParameter::create(
+        createMapNameEPSGCode(name, code));
+}
+
+static operation::ParameterValueNNPtr createLength(const std::string &value,
+                                                   const UnitOfMeasure &uom) {
+    return operation::ParameterValue::create(
+        common::Length(c_locale_stod(value), uom));
+}
+
+static operation::ParameterValueNNPtr createAngle(const std::string &value,
+                                                  const UnitOfMeasure &uom) {
+    return operation::ParameterValue::create(
+        common::Angle(c_locale_stod(value), uom));
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns a operation::CoordinateOperation from the specified code.
+ *
+ * @param code Object code allocated by authority.
+ * @param usePROJAlternativeGridNames Whether PROJ alternative grid names
+ * should be substituted to the official grid names.
+ * @return object.
+ * @throw NoSuchAuthorityCodeException
+ * @throw FactoryException
+ */
+
+operation::CoordinateOperationNNPtr AuthorityFactory::createCoordinateOperation(
+    const std::string &code, bool usePROJAlternativeGridNames) const {
+    return createCoordinateOperation(code, true, usePROJAlternativeGridNames,
+                                     std::string());
+}
+
+operation::CoordinateOperationNNPtr AuthorityFactory::createCoordinateOperation(
+    const std::string &code, bool allowConcatenated,
+    bool usePROJAlternativeGridNames, const std::string &typeIn) const {
+    std::string type(typeIn);
+    if (type.empty()) {
+        auto res = d->runWithCodeParam(
+            "SELECT type FROM coordinate_operation_with_conversion_view "
+            "WHERE auth_name = ? AND code = ?",
+            code);
+        if (res.empty()) {
+            throw NoSuchAuthorityCodeException("coordinate operation not found",
+                                               d->authority(), code);
+        }
+        type = res.front()[0];
+    }
+
+    if (type == "conversion") {
+        return createConversion(code);
+    }
+
+    if (type == "helmert_transformation") {
+
+        auto res = d->runWithCodeParam(
+            "SELECT name, method_auth_name, method_code, method_name, "
+            "source_crs_auth_name, source_crs_code, target_crs_auth_name, "
+            "target_crs_code, area_of_use_auth_name, area_of_use_code, "
+            "accuracy, tx, ty, tz, translation_uom_auth_name, "
+            "translation_uom_code, rx, ry, rz, rotation_uom_auth_name, "
+            "rotation_uom_code, scale_difference, "
+            "scale_difference_uom_auth_name, scale_difference_uom_code, "
+            "rate_tx, rate_ty, rate_tz, rate_translation_uom_auth_name, "
+            "rate_translation_uom_code, rate_rx, rate_ry, rate_rz, "
+            "rate_rotation_uom_auth_name, rate_rotation_uom_code, "
+            "rate_scale_difference, rate_scale_difference_uom_auth_name, "
+            "rate_scale_difference_uom_code, epoch, epoch_uom_auth_name, "
+            "epoch_uom_code, px, py, pz, pivot_uom_auth_name, pivot_uom_code, "
+            "deprecated FROM "
+            "helmert_transformation WHERE auth_name = ? AND code = ?",
+            code);
+        if (res.empty()) {
+            // shouldn't happen if foreign keys are OK
+            throw NoSuchAuthorityCodeException(
+                "helmert_transformation not found", d->authority(), code);
+        }
+        try {
+            const auto &row = res.front();
+            size_t idx = 0;
+            const auto &name = row[idx++];
+            const auto &method_auth_name = row[idx++];
+            const auto &method_code = row[idx++];
+            const auto &method_name = row[idx++];
+            const auto &source_crs_auth_name = row[idx++];
+            const auto &source_crs_code = row[idx++];
+            const auto &target_crs_auth_name = row[idx++];
+            const auto &target_crs_code = row[idx++];
+            const auto &area_of_use_auth_name = row[idx++];
+            const auto &area_of_use_code = row[idx++];
+            const auto &accuracy = row[idx++];
+
+            const auto &tx = row[idx++];
+            const auto &ty = row[idx++];
+            const auto &tz = row[idx++];
+            const auto &translation_uom_auth_name = row[idx++];
+            const auto &translation_uom_code = row[idx++];
+            const auto &rx = row[idx++];
+            const auto &ry = row[idx++];
+            const auto &rz = row[idx++];
+            const auto &rotation_uom_auth_name = row[idx++];
+            const auto &rotation_uom_code = row[idx++];
+            const auto &scale_difference = row[idx++];
+            const auto &scale_difference_uom_auth_name = row[idx++];
+            const auto &scale_difference_uom_code = row[idx++];
+
+            const auto &rate_tx = row[idx++];
+            const auto &rate_ty = row[idx++];
+            const auto &rate_tz = row[idx++];
+            const auto &rate_translation_uom_auth_name = row[idx++];
+            const auto &rate_translation_uom_code = row[idx++];
+            const auto &rate_rx = row[idx++];
+            const auto &rate_ry = row[idx++];
+            const auto &rate_rz = row[idx++];
+            const auto &rate_rotation_uom_auth_name = row[idx++];
+            const auto &rate_rotation_uom_code = row[idx++];
+            const auto &rate_scale_difference = row[idx++];
+            const auto &rate_scale_difference_uom_auth_name = row[idx++];
+            const auto &rate_scale_difference_uom_code = row[idx++];
+
+            const auto &epoch = row[idx++];
+            const auto &epoch_uom_auth_name = row[idx++];
+            const auto &epoch_uom_code = row[idx++];
+
+            const auto &px = row[idx++];
+            const auto &py = row[idx++];
+            const auto &pz = row[idx++];
+            const auto &pivot_uom_auth_name = row[idx++];
+            const auto &pivot_uom_code = row[idx++];
+
+            const auto &deprecated_str = row[idx++];
+            const bool deprecated = deprecated_str == "1";
+            assert(idx == row.size());
+
+            auto uom_translation = d->createUnitOfMeasure(
+                translation_uom_auth_name, translation_uom_code);
+
+            auto uom_epoch = epoch_uom_auth_name.empty()
+                                 ? common::UnitOfMeasure::NONE
+                                 : d->createUnitOfMeasure(epoch_uom_auth_name,
+                                                          epoch_uom_code);
+
+            auto sourceCRS =
+                d->createFactory(source_crs_auth_name)
+                    ->createCoordinateReferenceSystem(source_crs_code);
+            auto targetCRS =
+                d->createFactory(target_crs_auth_name)
+                    ->createCoordinateReferenceSystem(target_crs_code);
+
+            std::vector<operation::OperationParameterNNPtr> parameters;
+            std::vector<operation::ParameterValueNNPtr> values;
+
+            parameters.emplace_back(createOpParamNameEPSGCode(
+                EPSG_CODE_PARAMETER_X_AXIS_TRANSLATION));
+            values.emplace_back(createLength(tx, uom_translation));
+
+            parameters.emplace_back(createOpParamNameEPSGCode(
+                EPSG_CODE_PARAMETER_Y_AXIS_TRANSLATION));
+            values.emplace_back(createLength(ty, uom_translation));
+
+            parameters.emplace_back(createOpParamNameEPSGCode(
+                EPSG_CODE_PARAMETER_Z_AXIS_TRANSLATION));
+            values.emplace_back(createLength(tz, uom_translation));
+
+            if (!rx.empty()) {
+                // Helmert 7-, 8-, 10- or 15- parameter cases
+                auto uom_rotation = d->createUnitOfMeasure(
+                    rotation_uom_auth_name, rotation_uom_code);
+
+                parameters.emplace_back(createOpParamNameEPSGCode(
+                    EPSG_CODE_PARAMETER_X_AXIS_ROTATION));
+                values.emplace_back(createAngle(rx, uom_rotation));
+
+                parameters.emplace_back(createOpParamNameEPSGCode(
+                    EPSG_CODE_PARAMETER_Y_AXIS_ROTATION));
+                values.emplace_back(createAngle(ry, uom_rotation));
+
+                parameters.emplace_back(createOpParamNameEPSGCode(
+                    EPSG_CODE_PARAMETER_Z_AXIS_ROTATION));
+                values.emplace_back(createAngle(rz, uom_rotation));
+
+                auto uom_scale_difference =
+                    scale_difference_uom_auth_name.empty()
+                        ? common::UnitOfMeasure::NONE
+                        : d->createUnitOfMeasure(scale_difference_uom_auth_name,
+                                                 scale_difference_uom_code);
+
+                parameters.emplace_back(createOpParamNameEPSGCode(
+                    EPSG_CODE_PARAMETER_SCALE_DIFFERENCE));
+                values.emplace_back(operation::ParameterValue::create(
+                    common::Scale(c_locale_stod(scale_difference),
+                                  uom_scale_difference)));
+            }
+
+            if (!rate_tx.empty()) {
+                // Helmert 15-parameter
+
+                auto uom_rate_translation = d->createUnitOfMeasure(
+                    rate_translation_uom_auth_name, rate_translation_uom_code);
+
+                parameters.emplace_back(createOpParamNameEPSGCode(
+                    EPSG_CODE_PARAMETER_RATE_X_AXIS_TRANSLATION));
+                values.emplace_back(
+                    createLength(rate_tx, uom_rate_translation));
+
+                parameters.emplace_back(createOpParamNameEPSGCode(
+                    EPSG_CODE_PARAMETER_RATE_Y_AXIS_TRANSLATION));
+                values.emplace_back(
+                    createLength(rate_ty, uom_rate_translation));
+
+                parameters.emplace_back(createOpParamNameEPSGCode(
+                    EPSG_CODE_PARAMETER_RATE_Z_AXIS_TRANSLATION));
+                values.emplace_back(
+                    createLength(rate_tz, uom_rate_translation));
+
+                auto uom_rate_rotation = d->createUnitOfMeasure(
+                    rate_rotation_uom_auth_name, rate_rotation_uom_code);
+
+                parameters.emplace_back(createOpParamNameEPSGCode(
+                    EPSG_CODE_PARAMETER_RATE_X_AXIS_ROTATION));
+                values.emplace_back(createAngle(rate_rx, uom_rate_rotation));
+
+                parameters.emplace_back(createOpParamNameEPSGCode(
+                    EPSG_CODE_PARAMETER_RATE_Y_AXIS_ROTATION));
+                values.emplace_back(createAngle(rate_ry, uom_rate_rotation));
+
+                parameters.emplace_back(createOpParamNameEPSGCode(
+                    EPSG_CODE_PARAMETER_RATE_Z_AXIS_ROTATION));
+                values.emplace_back(createAngle(rate_rz, uom_rate_rotation));
+
+                auto uom_rate_scale_difference =
+                    d->createUnitOfMeasure(rate_scale_difference_uom_auth_name,
+                                           rate_scale_difference_uom_code);
+                parameters.emplace_back(createOpParamNameEPSGCode(
+                    EPSG_CODE_PARAMETER_RATE_SCALE_DIFFERENCE));
+                values.emplace_back(operation::ParameterValue::create(
+                    common::Scale(c_locale_stod(rate_scale_difference),
+                                  uom_rate_scale_difference)));
+
+                parameters.emplace_back(createOpParamNameEPSGCode(
+                    EPSG_CODE_PARAMETER_REFERENCE_EPOCH));
+                values.emplace_back(operation::ParameterValue::create(
+                    common::Measure(c_locale_stod(epoch), uom_epoch)));
+            } else if (uom_epoch != common::UnitOfMeasure::NONE) {
+                // Helmert 8-parameter
+                parameters.emplace_back(createOpParamNameEPSGCode(
+                    EPSG_CODE_PARAMETER_TRANSFORMATION_REFERENCE_EPOCH));
+                values.emplace_back(operation::ParameterValue::create(
+                    common::Measure(c_locale_stod(epoch), uom_epoch)));
+            } else if (!px.empty()) {
+                // Molodensky-Badekas case
+                auto uom_pivot =
+                    d->createUnitOfMeasure(pivot_uom_auth_name, pivot_uom_code);
+
+                parameters.emplace_back(createOpParamNameEPSGCode(
+                    EPSG_CODE_PARAMETER_ORDINATE_1_EVAL_POINT));
+                values.emplace_back(createLength(px, uom_pivot));
+
+                parameters.emplace_back(createOpParamNameEPSGCode(
+                    EPSG_CODE_PARAMETER_ORDINATE_2_EVAL_POINT));
+                values.emplace_back(createLength(py, uom_pivot));
+
+                parameters.emplace_back(createOpParamNameEPSGCode(
+                    EPSG_CODE_PARAMETER_ORDINATE_3_EVAL_POINT));
+                values.emplace_back(createLength(pz, uom_pivot));
+            }
+
+            auto props =
+                d->createProperties(code, name, deprecated,
+                                    area_of_use_auth_name, area_of_use_code);
+
+            auto propsMethod =
+                util::PropertyMap()
+                    .set(metadata::Identifier::CODESPACE_KEY, method_auth_name)
+                    .set(metadata::Identifier::CODE_KEY, method_code)
+                    .set(common::IdentifiedObject::NAME_KEY, method_name);
+
+            std::vector<metadata::PositionalAccuracyNNPtr> accuracies;
+            if (!accuracy.empty()) {
+                accuracies.emplace_back(
+                    metadata::PositionalAccuracy::create(accuracy));
+            }
+            return operation::Transformation::create(
+                props, sourceCRS, targetCRS, nullptr, propsMethod, parameters,
+                values, accuracies);
+
+        } catch (const std::exception &ex) {
+            throw buildFactoryException("transformation", code, ex);
+        }
+    }
+
+    if (type == "grid_transformation") {
+        auto res = d->runWithCodeParam(
+            "SELECT name, method_auth_name, method_code, method_name, "
+            "source_crs_auth_name, source_crs_code, target_crs_auth_name, "
+            "target_crs_code, area_of_use_auth_name, area_of_use_code, "
+            "accuracy, grid_param_auth_name, grid_param_code, grid_param_name, "
+            "grid_name, "
+            "grid2_param_auth_name, grid2_param_code, grid2_param_name, "
+            "grid2_name, "
+            "interpolation_crs_auth_name, interpolation_crs_code, deprecated "
+            "FROM "
+            "grid_transformation WHERE auth_name = ? AND code = ?",
+            code);
+        if (res.empty()) {
+            // shouldn't happen if foreign keys are OK
+            throw NoSuchAuthorityCodeException("grid_transformation not found",
+                                               d->authority(), code);
+        }
+        try {
+            const auto &row = res.front();
+            size_t idx = 0;
+            const auto &name = row[idx++];
+            const auto &method_auth_name = row[idx++];
+            const auto &method_code = row[idx++];
+            const auto &method_name = row[idx++];
+            const auto &source_crs_auth_name = row[idx++];
+            const auto &source_crs_code = row[idx++];
+            const auto &target_crs_auth_name = row[idx++];
+            const auto &target_crs_code = row[idx++];
+            const auto &area_of_use_auth_name = row[idx++];
+            const auto &area_of_use_code = row[idx++];
+            const auto &accuracy = row[idx++];
+            const auto &grid_param_auth_name = row[idx++];
+            const auto &grid_param_code = row[idx++];
+            const auto &grid_param_name = row[idx++];
+            const auto &grid_name = row[idx++];
+            const auto &grid2_param_auth_name = row[idx++];
+            const auto &grid2_param_code = row[idx++];
+            const auto &grid2_param_name = row[idx++];
+            const auto &grid2_name = row[idx++];
+            const auto &interpolation_crs_auth_name = row[idx++];
+            const auto &interpolation_crs_code = row[idx++];
+
+            const auto &deprecated_str = row[idx++];
+            const bool deprecated = deprecated_str == "1";
+            assert(idx == row.size());
+
+            auto sourceCRS =
+                d->createFactory(source_crs_auth_name)
+                    ->createCoordinateReferenceSystem(source_crs_code);
+            auto targetCRS =
+                d->createFactory(target_crs_auth_name)
+                    ->createCoordinateReferenceSystem(target_crs_code);
+            auto interpolationCRS =
+                interpolation_crs_auth_name.empty()
+                    ? nullptr
+                    : d->createFactory(interpolation_crs_auth_name)
+                          ->createCoordinateReferenceSystem(
+                              interpolation_crs_code)
+                          .as_nullable();
+
+            std::vector<operation::OperationParameterNNPtr> parameters;
+            std::vector<operation::ParameterValueNNPtr> values;
+
+            parameters.emplace_back(operation::OperationParameter::create(
+                util::PropertyMap()
+                    .set(common::IdentifiedObject::NAME_KEY, grid_param_name)
+                    .set(metadata::Identifier::CODESPACE_KEY,
+                         grid_param_auth_name)
+                    .set(metadata::Identifier::CODE_KEY, grid_param_code)));
+            values.emplace_back(
+                operation::ParameterValue::createFilename(grid_name));
+            if (!grid2_name.empty()) {
+                parameters.emplace_back(operation::OperationParameter::create(
+                    util::PropertyMap()
+                        .set(common::IdentifiedObject::NAME_KEY,
+                             grid2_param_name)
+                        .set(metadata::Identifier::CODESPACE_KEY,
+                             grid2_param_auth_name)
+                        .set(metadata::Identifier::CODE_KEY,
+                             grid2_param_code)));
+                values.emplace_back(
+                    operation::ParameterValue::createFilename(grid2_name));
+            }
+
+            auto props =
+                d->createProperties(code, name, deprecated,
+                                    area_of_use_auth_name, area_of_use_code);
+            auto propsMethod =
+                util::PropertyMap()
+                    .set(metadata::Identifier::CODESPACE_KEY, method_auth_name)
+                    .set(metadata::Identifier::CODE_KEY, method_code)
+                    .set(common::IdentifiedObject::NAME_KEY, method_name);
+
+            std::vector<metadata::PositionalAccuracyNNPtr> accuracies;
+            if (!accuracy.empty()) {
+                accuracies.emplace_back(
+                    metadata::PositionalAccuracy::create(accuracy));
+            }
+            auto transf = operation::Transformation::create(
+                props, sourceCRS, targetCRS, interpolationCRS, propsMethod,
+                parameters, values, accuracies);
+            if (usePROJAlternativeGridNames) {
+                return transf->substitutePROJAlternativeGridNames(d->context());
+            }
+            return transf;
+
+        } catch (const std::exception &ex) {
+            throw buildFactoryException("transformation", code, ex);
+        }
+    }
+
+    if (type == "other_transformation") {
+        std::ostringstream buffer;
+        buffer.imbue(std::locale::classic());
+        buffer
+            << "SELECT name, method_auth_name, method_code, method_name, "
+               "source_crs_auth_name, source_crs_code, target_crs_auth_name, "
+               "target_crs_code, area_of_use_auth_name, area_of_use_code, "
+               "accuracy";
+        constexpr int N_MAX_PARAMS = 7;
+        for (int i = 1; i <= N_MAX_PARAMS; ++i) {
+            buffer << ", param" << i << "_auth_name";
+            buffer << ", param" << i << "_code";
+            buffer << ", param" << i << "_name";
+            buffer << ", param" << i << "_value";
+            buffer << ", param" << i << "_uom_auth_name";
+            buffer << ", param" << i << "_uom_code";
+        }
+        buffer << ", deprecated FROM other_transformation WHERE auth_name = ? "
+                  "AND code = ?";
+
+        auto res = d->runWithCodeParam(buffer.str(), code);
+        if (res.empty()) {
+            // shouldn't happen if foreign keys are OK
+            throw NoSuchAuthorityCodeException("other_transformation not found",
+                                               d->authority(), code);
+        }
+        try {
+            const auto &row = res.front();
+            size_t idx = 0;
+            const auto &name = row[idx++];
+            const auto &method_auth_name = row[idx++];
+            const auto &method_code = row[idx++];
+            const auto &method_name = row[idx++];
+            const auto &source_crs_auth_name = row[idx++];
+            const auto &source_crs_code = row[idx++];
+            const auto &target_crs_auth_name = row[idx++];
+            const auto &target_crs_code = row[idx++];
+            const auto &area_of_use_auth_name = row[idx++];
+            const auto &area_of_use_code = row[idx++];
+            const auto &accuracy = row[idx++];
+
+            const size_t base_param_idx = idx;
+            std::vector<operation::OperationParameterNNPtr> parameters;
+            std::vector<operation::ParameterValueNNPtr> values;
+            for (int i = 0; i < N_MAX_PARAMS; ++i) {
+                const auto &param_auth_name = row[base_param_idx + i * 6 + 0];
+                if (param_auth_name.empty()) {
+                    break;
+                }
+                const auto &param_code = row[base_param_idx + i * 6 + 1];
+                const auto &param_name = row[base_param_idx + i * 6 + 2];
+                const auto &param_value = row[base_param_idx + i * 6 + 3];
+                const auto &param_uom_auth_name =
+                    row[base_param_idx + i * 6 + 4];
+                const auto &param_uom_code = row[base_param_idx + i * 6 + 5];
+                parameters.emplace_back(operation::OperationParameter::create(
+                    util::PropertyMap()
+                        .set(metadata::Identifier::CODESPACE_KEY,
+                             param_auth_name)
+                        .set(metadata::Identifier::CODE_KEY, param_code)
+                        .set(common::IdentifiedObject::NAME_KEY, param_name)));
+                std::string normalized_uom_code(param_uom_code);
+                const double normalized_value = normalizeMeasure(
+                    param_uom_code, param_value, normalized_uom_code);
+                auto uom = d->createUnitOfMeasure(param_uom_auth_name,
+                                                  normalized_uom_code);
+                values.emplace_back(operation::ParameterValue::create(
+                    common::Measure(normalized_value, uom)));
+            }
+            idx = base_param_idx + 6 * N_MAX_PARAMS;
+
+            const auto &deprecated_str = row[idx++];
+            const bool deprecated = deprecated_str == "1";
+            assert(idx == row.size());
+
+            auto sourceCRS =
+                d->createFactory(source_crs_auth_name)
+                    ->createCoordinateReferenceSystem(source_crs_code);
+            auto targetCRS =
+                d->createFactory(target_crs_auth_name)
+                    ->createCoordinateReferenceSystem(target_crs_code);
+
+            auto props =
+                d->createProperties(code, name, deprecated,
+                                    area_of_use_auth_name, area_of_use_code);
+
+            std::vector<metadata::PositionalAccuracyNNPtr> accuracies;
+            if (!accuracy.empty()) {
+                accuracies.emplace_back(
+                    metadata::PositionalAccuracy::create(accuracy));
+            }
+
+            if (method_auth_name == "PROJ") {
+                if (method_code == "PROJString") {
+                    return operation::SingleOperation::createPROJBased(
+                        props, method_name, sourceCRS, targetCRS, accuracies);
+                } else if (method_code == "WKT") {
+                    auto op = util::nn_dynamic_pointer_cast<
+                        operation::CoordinateOperation>(
+                        WKTParser().createFromWKT(method_name));
+                    if (!op) {
+                        throw FactoryException("WKT string does not express a "
+                                               "coordinate operation");
+                    }
+                    op->setCRSs(sourceCRS, targetCRS, nullptr);
+                    return NN_NO_CHECK(op);
+                }
+            }
+
+            auto propsMethod =
+                util::PropertyMap()
+                    .set(metadata::Identifier::CODESPACE_KEY, method_auth_name)
+                    .set(metadata::Identifier::CODE_KEY, method_code)
+                    .set(common::IdentifiedObject::NAME_KEY, method_name);
+
+            if (method_auth_name == metadata::Identifier::EPSG &&
+                operation::isAxisOrderReversal(
+                    std::atoi(method_code.c_str()))) {
+                auto op = operation::Conversion::create(props, propsMethod,
+                                                        parameters, values);
+                op->setCRSs(sourceCRS, targetCRS, nullptr);
+                return op;
+            }
+            return operation::Transformation::create(
+                props, sourceCRS, targetCRS, nullptr, propsMethod, parameters,
+                values, accuracies);
+
+        } catch (const std::exception &ex) {
+            throw buildFactoryException("transformation", code, ex);
+        }
+    }
+
+    if (allowConcatenated && type == "concatenated_operation") {
+        auto res = d->runWithCodeParam(
+            "SELECT name, source_crs_auth_name, source_crs_code, "
+            "target_crs_auth_name, target_crs_code, "
+            "area_of_use_auth_name, area_of_use_code, accuracy, "
+            "step1_auth_name, step1_code, step2_auth_name, step2_code, "
+            "step3_auth_name, step3_code, deprecated FROM "
+            "concatenated_operation WHERE auth_name = ? AND code = ?",
+            code);
+        if (res.empty()) {
+            // shouldn't happen if foreign keys are OK
+            throw NoSuchAuthorityCodeException(
+                "concatenated_operation not found", d->authority(), code);
+        }
+        try {
+            const auto &row = res.front();
+            size_t idx = 0;
+            const auto &name = row[idx++];
+            const auto &source_crs_auth_name = row[idx++];
+            const auto &source_crs_code = row[idx++];
+            const auto &target_crs_auth_name = row[idx++];
+            const auto &target_crs_code = row[idx++];
+            const auto &area_of_use_auth_name = row[idx++];
+            const auto &area_of_use_code = row[idx++];
+            const auto &accuracy = row[idx++];
+            const auto &step1_auth_name = row[idx++];
+            const auto &step1_code = row[idx++];
+            const auto &step2_auth_name = row[idx++];
+            const auto &step2_code = row[idx++];
+            const auto &step3_auth_name = row[idx++];
+            const auto &step3_code = row[idx++];
+            const auto &deprecated_str = row[idx++];
+            const bool deprecated = deprecated_str == "1";
+
+            std::vector<operation::CoordinateOperationNNPtr> operations;
+            operations.push_back(
+                d->createFactory(step1_auth_name)
+                    ->createCoordinateOperation(step1_code, false,
+                                                usePROJAlternativeGridNames,
+                                                std::string()));
+            operations.push_back(
+                d->createFactory(step2_auth_name)
+                    ->createCoordinateOperation(step2_code, false,
+                                                usePROJAlternativeGridNames,
+                                                std::string()));
+
+            if (!step3_auth_name.empty()) {
+                operations.push_back(
+                    d->createFactory(step3_auth_name)
+                        ->createCoordinateOperation(step3_code, false,
+                                                    usePROJAlternativeGridNames,
+                                                    std::string()));
+            }
+
+            // In case the operation is a conversion (we hope this is the
+            // forward case!)
+            if (!operations[0]->sourceCRS() || !operations[0]->targetCRS()) {
+                if (!operations[1]->sourceCRS()) {
+                    throw FactoryException(
+                        "chaining of conversion not supported");
+                }
+                operations[0]->setCRSs(
+                    d->createFactory(source_crs_auth_name)
+                        ->createCoordinateReferenceSystem(source_crs_code),
+                    NN_NO_CHECK(operations[1]->sourceCRS()), nullptr);
+            }
+
+            // Some concatenated operations, like 8443, might actually chain
+            // reverse operations rather than forward operations.
+            {
+                const auto &op0SrcId =
+                    operations[0]->sourceCRS()->identifiers()[0];
+                if (op0SrcId->code() != source_crs_code ||
+                    *op0SrcId->codeSpace() != source_crs_auth_name) {
+                    operations[0] = operations[0]->inverse();
+                }
+            }
+
+            {
+                const auto &op0SrcId =
+                    operations[0]->sourceCRS()->identifiers()[0];
+                if (op0SrcId->code() != source_crs_code ||
+                    *op0SrcId->codeSpace() != source_crs_auth_name) {
+                    throw FactoryException(
+                        "Source CRS of first operation in concatenated "
+                        "operation " +
+                        code + " does not match source CRS of "
+                               "concatenated operation");
+                }
+            }
+
+            // In case the operation is a conversion (we hope this is the
+            // forward case!)
+            if (!operations[1]->sourceCRS() || !operations[1]->targetCRS()) {
+                if (step3_auth_name.empty()) {
+                    operations[1]->setCRSs(
+                        NN_NO_CHECK(operations[0]->targetCRS()),
+                        d->createFactory(target_crs_auth_name)
+                            ->createCoordinateReferenceSystem(target_crs_code),
+                        nullptr);
+                } else {
+                    if (!operations[2]->sourceCRS()) {
+                        throw FactoryException(
+                            "chaining of conversion not supported");
+                    }
+                    operations[1]->setCRSs(
+                        NN_NO_CHECK(operations[0]->targetCRS()),
+                        NN_NO_CHECK(operations[2]->sourceCRS()), nullptr);
+                }
+            }
+
+            const auto &op1SrcId = operations[1]->sourceCRS()->identifiers()[0];
+            const auto &op0TargetId =
+                operations[0]->targetCRS()->identifiers()[0];
+            while (true) {
+                if (step3_auth_name.empty()) {
+                    const auto &opLastTargetId =
+                        operations.back()->targetCRS()->identifiers()[0];
+                    if (opLastTargetId->code() == target_crs_code &&
+                        *opLastTargetId->codeSpace() == target_crs_auth_name) {
+                        // in case we have only 2 steps, and
+                        // step2.targetCRS == concatenate.targetCRS do nothing,
+                        // but ConcatenatedOperation::create() will ultimately
+                        // check that step1.targetCRS == step2.sourceCRS
+                        break;
+                    }
+                }
+                if (op1SrcId->code() != op0TargetId->code() ||
+                    *op1SrcId->codeSpace() != *op0TargetId->codeSpace()) {
+                    operations[1] = operations[1]->inverse();
+                }
+                break;
+            }
+
+            if (!step3_auth_name.empty()) {
+
+                const auto &op2Src = operations[2]->sourceCRS();
+                // In case the operation is a conversion (we hope this is the
+                // forward case!)
+                if (!op2Src || !operations[2]->targetCRS()) {
+                    operations[2]->setCRSs(
+                        NN_NO_CHECK(operations[1]->targetCRS()),
+                        d->createFactory(target_crs_auth_name)
+                            ->createCoordinateReferenceSystem(target_crs_code),
+                        nullptr);
+                }
+
+                const auto &op2SrcId = op2Src->identifiers()[0];
+                const auto &op1TargetId =
+                    operations[1]->targetCRS()->identifiers()[0];
+                if (op2SrcId->code() != op1TargetId->code() ||
+                    *op2SrcId->codeSpace() != *op1TargetId->codeSpace()) {
+                    operations[2] = operations[2]->inverse();
+                }
+            }
+
+            const auto &opLastTargetId =
+                operations.back()->targetCRS()->identifiers()[0];
+            if (opLastTargetId->code() != target_crs_code ||
+                *opLastTargetId->codeSpace() != target_crs_auth_name) {
+                throw FactoryException(
+                    "Target CRS of last operation in concatenated operation " +
+                    code +
+                    " doest not match target CRS of concatenated operation");
+            }
+
+            auto props =
+                d->createProperties(code, name, deprecated,
+                                    area_of_use_auth_name, area_of_use_code);
+
+            std::vector<metadata::PositionalAccuracyNNPtr> accuracies;
+            if (!accuracy.empty()) {
+                accuracies.emplace_back(
+                    metadata::PositionalAccuracy::create(accuracy));
+            } else {
+                // Try to compute a reasonable accuracy from the members
+                double totalAcc = -1;
+                try {
+                    for (const auto &op : operations) {
+                        auto accs = op->coordinateOperationAccuracies();
+                        if (accs.size() == 1) {
+                            double acc = c_locale_stod(accs[0]->value());
+                            if (totalAcc < 0) {
+                                totalAcc = acc;
+                            } else {
+                                totalAcc += acc;
+                            }
+                        } else {
+                            totalAcc = -1;
+                            break;
+                        }
+                    }
+                    if (totalAcc >= 0) {
+                        accuracies.emplace_back(
+                            metadata::PositionalAccuracy::create(
+                                toString(totalAcc)));
+                    }
+                } catch (const std::exception &) {
+                }
+            }
+            return operation::ConcatenatedOperation::create(props, operations,
+                                                            accuracies);
+
+        } catch (const std::exception &ex) {
+            throw buildFactoryException("transformation", code, ex);
+        }
+    }
+
+    throw FactoryException("unhandled coordinate operation type: " + type);
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns a list operation::CoordinateOperation between two CRS.
+ *
+ * The list is ordered with preferred operations first. No attempt is made
+ * at infering operations that are not explicitly in the database.
+ *
+ * Deprecated operations are rejected.
+ *
+ * @param sourceCRSCode Source CRS code allocated by authority.
+ * @param targetCRSCode Source CRS code allocated by authority.
+ * @return list of coordinate operations
+ * @throw NoSuchAuthorityCodeException
+ * @throw FactoryException
+ */
+
+std::vector<operation::CoordinateOperationNNPtr>
+AuthorityFactory::createFromCoordinateReferenceSystemCodes(
+    const std::string &sourceCRSCode, const std::string &targetCRSCode) const {
+    return createFromCoordinateReferenceSystemCodes(
+        d->authority(), sourceCRSCode, d->authority(), targetCRSCode, false,
+        false, false);
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns a list operation::CoordinateOperation between two CRS.
+ *
+ * The list is ordered with preferred operations first. No attempt is made
+ * at infering operations that are not explicitly in the database (see
+ * createFromCRSCodesWithIntermediates() for that), and only
+ * source -> target operations are searched (ie if target -> source is present,
+ * you need to call this method with the arguments reversed, and apply the
+ * reverse transformations).
+ *
+ * Deprecated operations are rejected.
+ *
+ * If getAuthority() returns empty, then coordinate operations from all
+ * authorities are considered.
+ *
+ * @param sourceCRSAuthName Authority name of sourceCRSCode
+ * @param sourceCRSCode Source CRS code allocated by authority
+ * sourceCRSAuthName.
+ * @param targetCRSAuthName Authority name of targetCRSCode
+ * @param targetCRSCode Source CRS code allocated by authority
+ * targetCRSAuthName.
+ * @param usePROJAlternativeGridNames Whether PROJ alternative grid names
+ * should be substituted to the official grid names.
+ * @param discardIfMissingGrid Whether coordinate operations that reference
+ * missing grids should be removed from the result set.
+ * @param discardSuperseded Whether cordinate operations that are superseded
+ * (but not deprecated) should be removed from the result set.
+ * @return list of coordinate operations
+ * @throw NoSuchAuthorityCodeException
+ * @throw FactoryException
+ */
+
+std::vector<operation::CoordinateOperationNNPtr>
+AuthorityFactory::createFromCoordinateReferenceSystemCodes(
+    const std::string &sourceCRSAuthName, const std::string &sourceCRSCode,
+    const std::string &targetCRSAuthName, const std::string &targetCRSCode,
+    bool usePROJAlternativeGridNames, bool discardIfMissingGrid,
+    bool discardSuperseded) const {
+
+    auto cacheKey(d->authority());
+    cacheKey += sourceCRSAuthName;
+    cacheKey += sourceCRSCode;
+    cacheKey += targetCRSAuthName;
+    cacheKey += targetCRSCode;
+    cacheKey += (usePROJAlternativeGridNames ? '1' : '0');
+    cacheKey += (discardIfMissingGrid ? '1' : '0');
+    cacheKey += (discardSuperseded ? '1' : '0');
+
+    std::vector<operation::CoordinateOperationNNPtr> list;
+
+    if (d->context()->d->getCRSToCRSCoordOpFromCache(cacheKey, list)) {
+        return list;
+    }
+
+    // Look-up first for conversion which is the most precise.
+    std::string sql("SELECT conversion_auth_name, "
+                    "geodetic_crs_auth_name, geodetic_crs_code FROM "
+                    "projected_crs WHERE auth_name = ? AND code = ?");
+    auto params = ListOfParams{targetCRSAuthName, targetCRSCode};
+    auto res = d->run(sql, params);
+    if (!res.empty()) {
+        const auto &row = res.front();
+        bool ok = row[1] == sourceCRSAuthName && row[2] == sourceCRSCode;
+        if (ok && d->hasAuthorityRestriction()) {
+            ok = row[0] == d->authority();
+        }
+        if (ok) {
+            auto targetCRS = d->createFactory(targetCRSAuthName)
+                                 ->createProjectedCRS(targetCRSCode);
+            auto conv = targetCRS->derivingConversion();
+            list.emplace_back(conv);
+            d->context()->d->cache(cacheKey, list);
+            return list;
+        }
+    }
+    if (discardSuperseded) {
+        sql = "SELECT cov.auth_name, cov.code, cov.table_name, "
+              "ss.replacement_auth_name, ss.replacement_code FROM "
+              "coordinate_operation_view cov JOIN area "
+              "ON cov.area_of_use_auth_name = area.auth_name AND "
+              "cov.area_of_use_code = area.code "
+              "LEFT JOIN supersession ss ON "
+              "ss.superseded_table_name = cov.table_name AND "
+              "ss.superseded_auth_name = cov.auth_name AND "
+              "ss.superseded_code = cov.code AND "
+              "ss.superseded_table_name = ss.replacement_table_name "
+              "WHERE source_crs_auth_name = ? AND source_crs_code = ? AND "
+              "target_crs_auth_name = ? AND target_crs_code = ? AND "
+              "cov.deprecated = 0";
+    } else {
+        sql = "SELECT cov.auth_name, cov.code, cov.table_name FROM "
+              "coordinate_operation_view cov JOIN area "
+              "ON cov.area_of_use_auth_name = area.auth_name AND "
+              "cov.area_of_use_code = area.code "
+              "WHERE source_crs_auth_name = ? AND source_crs_code = ? AND "
+              "target_crs_auth_name = ? AND target_crs_code = ? AND "
+              "cov.deprecated = 0";
+    }
+    params = {sourceCRSAuthName, sourceCRSCode, targetCRSAuthName,
+              targetCRSCode};
+    if (d->hasAuthorityRestriction()) {
+        sql += " AND cov.auth_name = ?";
+        params.emplace_back(d->authority());
+    }
+    sql += " ORDER BY pseudo_area_from_swne(south_lat, west_lon, north_lat, "
+           "east_lon) DESC, "
+           "(CASE WHEN accuracy is NULL THEN 1 ELSE 0 END), accuracy";
+    res = d->run(sql, params);
+    std::set<std::pair<std::string, std::string>> setTransf;
+    if (discardSuperseded) {
+        for (const auto &row : res) {
+            const auto &auth_name = row[0];
+            const auto &code = row[1];
+            setTransf.insert(
+                std::pair<std::string, std::string>(auth_name, code));
+        }
+    }
+    for (const auto &row : res) {
+        if (discardSuperseded) {
+            const auto &replacement_auth_name = row[3];
+            const auto &replacement_code = row[4];
+            if (!replacement_auth_name.empty() &&
+                setTransf.find(std::pair<std::string, std::string>(
+                    replacement_auth_name, replacement_code)) !=
+                    setTransf.end()) {
+                // Skip transformations that are superseded by others that got
+                // returned in the result set.
+                continue;
+            }
+        }
+
+        const auto &auth_name = row[0];
+        const auto &code = row[1];
+        const auto &table_name = row[2];
+        auto op = d->createFactory(auth_name)->createCoordinateOperation(
+            code, true, usePROJAlternativeGridNames, table_name);
+        if (!d->rejectOpDueToMissingGrid(op, discardIfMissingGrid)) {
+            list.emplace_back(op);
+        }
+    }
+    d->context()->d->cache(cacheKey, list);
+    return list;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static std::string
+buildIntermediateWhere(const std::vector<std::pair<std::string, std::string>>
+                           &intermediateCRSAuthCodes,
+                       const std::string &first_field,
+                       const std::string &second_field) {
+    if (intermediateCRSAuthCodes.empty()) {
+        return std::string();
+    }
+    std::string sql(" AND (");
+    for (size_t i = 0; i < intermediateCRSAuthCodes.size(); ++i) {
+        if (i > 0) {
+            sql += " OR";
+        }
+        sql += "(v1." + first_field + "_crs_auth_name = ? AND ";
+        sql += "v1." + first_field + "_crs_code = ? AND ";
+        sql += "v2." + second_field + "_crs_auth_name = ? AND ";
+        sql += "v2." + second_field + "_crs_code = ?) ";
+    }
+    sql += ")";
+    return sql;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static bool useIrrelevantPivot(const operation::CoordinateOperationNNPtr &op,
+                               const std::string &sourceCRSAuthName,
+                               const std::string &sourceCRSCode,
+                               const std::string &targetCRSAuthName,
+                               const std::string &targetCRSCode) {
+    auto concat =
+        dynamic_cast<const operation::ConcatenatedOperation *>(op.get());
+    if (!concat) {
+        return false;
+    }
+    auto ops = concat->operations();
+    for (size_t i = 0; i + 1 < ops.size(); i++) {
+        auto targetCRS = ops[i]->targetCRS();
+        if (targetCRS) {
+            const auto &ids = targetCRS->identifiers();
+            if (ids.size() == 1 &&
+                ((*ids[0]->codeSpace() == sourceCRSAuthName &&
+                  ids[0]->code() == sourceCRSCode) ||
+                 (*ids[0]->codeSpace() == targetCRSAuthName &&
+                  ids[0]->code() == targetCRSCode))) {
+                return true;
+            }
+        }
+    }
+    return false;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns a list operation::CoordinateOperation between two CRS,
+ * using intermediate codes.
+ *
+ * The list is ordered with preferred operations first.
+ *
+ * Deprecated operations are rejected.
+ *
+ * The method will take care of considering all potential combinations (ie
+ * contrary to createFromCoordinateReferenceSystemCodes(), you do not need to
+ * call it with sourceCRS and targetCRS switched)
+ *
+ * If getAuthority() returns empty, then coordinate operations from all
+ * authorities are considered.
+ *
+ * @param sourceCRSAuthName Authority name of sourceCRSCode
+ * @param sourceCRSCode Source CRS code allocated by authority
+ * sourceCRSAuthName.
+ * @param targetCRSAuthName Authority name of targetCRSCode
+ * @param targetCRSCode Source CRS code allocated by authority
+ * targetCRSAuthName.
+ * @param usePROJAlternativeGridNames Whether PROJ alternative grid names
+ * should be substituted to the official grid names.
+ * @param discardIfMissingGrid Whether coordinate operations that reference
+ * missing grids should be removed from the result set.
+ * @param discardSuperseded Whether cordinate operations that are superseded
+ * (but not deprecated) should be removed from the result set.
+ * @param intermediateCRSAuthCodes List of (auth_name, code) of CRS that can be
+ * used as potential intermediate CRS. If the list is empty, the database will
+ * be used to find common CRS in operations involving both the source and
+ * target CRS.
+ * @return list of coordinate operations
+ * @throw NoSuchAuthorityCodeException
+ * @throw FactoryException
+ */
+
+std::vector<operation::CoordinateOperationNNPtr>
+AuthorityFactory::createFromCRSCodesWithIntermediates(
+    const std::string &sourceCRSAuthName, const std::string &sourceCRSCode,
+    const std::string &targetCRSAuthName, const std::string &targetCRSCode,
+    bool usePROJAlternativeGridNames, bool discardIfMissingGrid,
+    bool discardSuperseded,
+    const std::vector<std::pair<std::string, std::string>>
+        &intermediateCRSAuthCodes) const {
+
+    std::vector<operation::CoordinateOperationNNPtr> listTmp;
+
+    if (sourceCRSAuthName == targetCRSAuthName &&
+        sourceCRSCode == targetCRSCode) {
+        return listTmp;
+    }
+
+    const std::string sqlProlog(
+        discardSuperseded
+            ?
+
+            "SELECT v1.table_name as table1, "
+            "v1.auth_name AS auth_name1, v1.code AS code1, "
+            "v1.accuracy AS accuracy1, "
+            "v2.table_name as table2, "
+            "v2.auth_name AS auth_name2, v2.code AS code2, "
+            "v2.accuracy as accuracy2, "
+            "a1.south_lat AS south_lat1, "
+            "a1.west_lon AS west_lon1, "
+            "a1.north_lat AS north_lat1, "
+            "a1.east_lon AS east_lon1, "
+            "a2.south_lat AS south_lat2, "
+            "a2.west_lon AS west_lon2, "
+            "a2.north_lat AS north_lat2, "
+            "a2.east_lon AS east_lon2, "
+            "ss1.replacement_auth_name AS replacement_auth_name1, "
+            "ss1.replacement_code AS replacement_code1, "
+            "ss2.replacement_auth_name AS replacement_auth_name2, "
+            "ss2.replacement_code AS replacement_code2 "
+            "FROM coordinate_operation_view v1 "
+            "JOIN coordinate_operation_view v2 "
+            :
+
+            "SELECT v1.table_name as table1, "
+            "v1.auth_name AS auth_name1, v1.code AS code1, "
+            "v1.accuracy AS accuracy1, "
+            "v2.table_name as table2, "
+            "v2.auth_name AS auth_name2, v2.code AS code2, "
+            "v2.accuracy as accuracy2, "
+            "a1.south_lat AS south_lat1, "
+            "a1.west_lon AS west_lon1, "
+            "a1.north_lat AS north_lat1, "
+            "a1.east_lon AS east_lon1, "
+            "a2.south_lat AS south_lat2, "
+            "a2.west_lon AS west_lon2, "
+            "a2.north_lat AS north_lat2, "
+            "a2.east_lon AS east_lon2 "
+            "FROM coordinate_operation_view v1 "
+            "JOIN coordinate_operation_view v2 ");
+
+    const std::string joinSupersession(
+        "LEFT JOIN supersession ss1 ON "
+        "ss1.superseded_table_name = v1.table_name AND "
+        "ss1.superseded_auth_name = v1.auth_name AND "
+        "ss1.superseded_code = v1.code AND "
+        "ss1.superseded_table_name = ss1.replacement_table_name "
+        "LEFT JOIN supersession ss2 ON "
+        "ss2.superseded_table_name = v2.table_name AND "
+        "ss2.superseded_auth_name = v2.auth_name AND "
+        "ss2.superseded_code = v2.code AND "
+        "ss2.superseded_table_name = ss2.replacement_table_name ");
+    const std::string joinArea(
+        (discardSuperseded ? joinSupersession : std::string()) +
+        "JOIN area a1 ON v1.area_of_use_auth_name = a1.auth_name "
+        "AND v1.area_of_use_code = a1.code "
+        "JOIN area a2 ON v2.area_of_use_auth_name = a2.auth_name "
+        "AND v2.area_of_use_code = a2.code ");
+    const std::string orderBy(
+        "ORDER BY (CASE WHEN accuracy1 is NULL THEN 1 ELSE 0 END) + "
+        "(CASE WHEN accuracy2 is NULL THEN 1 ELSE 0 END), "
+        "accuracy1 + accuracy2");
+
+    // Case (source->intermediate) and (intermediate->target)
+    std::string sql(
+        sqlProlog + "ON v1.target_crs_auth_name = v2.source_crs_auth_name "
+                    "AND v1.target_crs_code = v2.source_crs_code " +
+        joinArea +
+        "WHERE v1.source_crs_auth_name = ? AND v1.source_crs_code = ? "
+        "AND v2.target_crs_auth_name = ? AND v2.target_crs_code = ? ");
+    auto params = ListOfParams{sourceCRSAuthName, sourceCRSCode,
+                               targetCRSAuthName, targetCRSCode};
+
+    std::string additionalWhere(
+        "AND v1.deprecated = 0 AND v2.deprecated = 0 "
+        "AND intersects_bbox(south_lat1, west_lon1, north_lat1, east_lon1, "
+        "south_lat2, west_lon2, north_lat2, east_lon2) == 1 ");
+    if (d->hasAuthorityRestriction()) {
+        additionalWhere += "AND v1.auth_name = ? AND v2.auth_name = ? ";
+        params.emplace_back(d->authority());
+        params.emplace_back(d->authority());
+    }
+    std::string intermediateWhere =
+        buildIntermediateWhere(intermediateCRSAuthCodes, "target", "source");
+    for (const auto &pair : intermediateCRSAuthCodes) {
+        params.emplace_back(pair.first);
+        params.emplace_back(pair.second);
+        params.emplace_back(pair.first);
+        params.emplace_back(pair.second);
+    }
+    auto res =
+        d->run(sql + additionalWhere + intermediateWhere + orderBy, params);
+
+    const auto filterOutSuperseded = [](SQLResultSet &&resultSet) {
+        std::set<std::pair<std::string, std::string>> setTransf1;
+        std::set<std::pair<std::string, std::string>> setTransf2;
+        for (const auto &row : resultSet) {
+            // table1
+            const auto &auth_name1 = row[1];
+            const auto &code1 = row[2];
+            // accuracy1
+            // table2
+            const auto &auth_name2 = row[5];
+            const auto &code2 = row[6];
+            setTransf1.insert(
+                std::pair<std::string, std::string>(auth_name1, code1));
+            setTransf2.insert(
+                std::pair<std::string, std::string>(auth_name2, code2));
+        }
+        SQLResultSet filteredResultSet;
+        for (const auto &row : resultSet) {
+            const auto &replacement_auth_name1 = row[16];
+            const auto &replacement_code1 = row[17];
+            const auto &replacement_auth_name2 = row[18];
+            const auto &replacement_code2 = row[19];
+            if (!replacement_auth_name1.empty() &&
+                setTransf1.find(std::pair<std::string, std::string>(
+                    replacement_auth_name1, replacement_code1)) !=
+                    setTransf1.end()) {
+                // Skip transformations that are superseded by others that got
+                // returned in the result set.
+                continue;
+            }
+            if (!replacement_auth_name2.empty() &&
+                setTransf2.find(std::pair<std::string, std::string>(
+                    replacement_auth_name2, replacement_code2)) !=
+                    setTransf2.end()) {
+                // Skip transformations that are superseded by others that got
+                // returned in the result set.
+                continue;
+            }
+            filteredResultSet.emplace_back(row);
+        }
+        return filteredResultSet;
+    };
+
+    if (discardSuperseded) {
+        res = filterOutSuperseded(std::move(res));
+    }
+    for (const auto &row : res) {
+        const auto &table1 = row[0];
+        const auto &auth_name1 = row[1];
+        const auto &code1 = row[2];
+        // const auto &accuracy1 = row[3];
+        const auto &table2 = row[4];
+        const auto &auth_name2 = row[5];
+        const auto &code2 = row[6];
+        // const auto &accuracy2 = row[7];
+        auto op1 = d->createFactory(auth_name1)
+                       ->createCoordinateOperation(
+                           code1, true, usePROJAlternativeGridNames, table1);
+        if (useIrrelevantPivot(op1, sourceCRSAuthName, sourceCRSCode,
+                               targetCRSAuthName, targetCRSCode)) {
+            continue;
+        }
+        auto op2 = d->createFactory(auth_name2)
+                       ->createCoordinateOperation(
+                           code2, true, usePROJAlternativeGridNames, table2);
+        if (useIrrelevantPivot(op2, sourceCRSAuthName, sourceCRSCode,
+                               targetCRSAuthName, targetCRSCode)) {
+            continue;
+        }
+
+        listTmp.emplace_back(
+            operation::ConcatenatedOperation::createComputeMetadata({op1, op2},
+                                                                    false));
+    }
+
+    // Case (source->intermediate) and (target->intermediate)
+    sql = sqlProlog + "ON v1.target_crs_auth_name = v2.target_crs_auth_name "
+                      "AND v1.target_crs_code = v2.target_crs_code " +
+          joinArea +
+          "WHERE v1.source_crs_auth_name = ? AND v1.source_crs_code = ? "
+          "AND v2.source_crs_auth_name = ? AND v2.source_crs_code = ? ";
+    intermediateWhere =
+        buildIntermediateWhere(intermediateCRSAuthCodes, "target", "target");
+    res = d->run(sql + additionalWhere + intermediateWhere + orderBy, params);
+    if (discardSuperseded) {
+        res = filterOutSuperseded(std::move(res));
+    }
+    for (const auto &row : res) {
+        const auto &table1 = row[0];
+        const auto &auth_name1 = row[1];
+        const auto &code1 = row[2];
+        // const auto &accuracy1 = row[3];
+        const auto &table2 = row[4];
+        const auto &auth_name2 = row[5];
+        const auto &code2 = row[6];
+        // const auto &accuracy2 = row[7];
+        auto op1 = d->createFactory(auth_name1)
+                       ->createCoordinateOperation(
+                           code1, true, usePROJAlternativeGridNames, table1);
+        if (useIrrelevantPivot(op1, sourceCRSAuthName, sourceCRSCode,
+                               targetCRSAuthName, targetCRSCode)) {
+            continue;
+        }
+        auto op2 = d->createFactory(auth_name2)
+                       ->createCoordinateOperation(
+                           code2, true, usePROJAlternativeGridNames, table2);
+        if (useIrrelevantPivot(op2, sourceCRSAuthName, sourceCRSCode,
+                               targetCRSAuthName, targetCRSCode)) {
+            continue;
+        }
+
+        listTmp.emplace_back(
+            operation::ConcatenatedOperation::createComputeMetadata(
+                {op1, op2->inverse()}, false));
+    }
+
+    // Case (intermediate->source) and (intermediate->target)
+    sql = sqlProlog + "ON v1.source_crs_auth_name = v2.source_crs_auth_name "
+                      "AND v1.source_crs_code = v2.source_crs_code " +
+          joinArea +
+          "WHERE v1.target_crs_auth_name = ? AND v1.target_crs_code = ? "
+          "AND v2.target_crs_auth_name = ? AND v2.target_crs_code = ? ";
+    intermediateWhere =
+        buildIntermediateWhere(intermediateCRSAuthCodes, "source", "source");
+    res = d->run(sql + additionalWhere + intermediateWhere + orderBy, params);
+    if (discardSuperseded) {
+        res = filterOutSuperseded(std::move(res));
+    }
+    for (const auto &row : res) {
+        const auto &table1 = row[0];
+        const auto &auth_name1 = row[1];
+        const auto &code1 = row[2];
+        // const auto &accuracy1 = row[3];
+        const auto &table2 = row[4];
+        const auto &auth_name2 = row[5];
+        const auto &code2 = row[6];
+        // const auto &accuracy2 = row[7];
+        auto op1 = d->createFactory(auth_name1)
+                       ->createCoordinateOperation(
+                           code1, true, usePROJAlternativeGridNames, table1);
+        if (useIrrelevantPivot(op1, sourceCRSAuthName, sourceCRSCode,
+                               targetCRSAuthName, targetCRSCode)) {
+            continue;
+        }
+        auto op2 = d->createFactory(auth_name2)
+                       ->createCoordinateOperation(
+                           code2, true, usePROJAlternativeGridNames, table2);
+        if (useIrrelevantPivot(op2, sourceCRSAuthName, sourceCRSCode,
+                               targetCRSAuthName, targetCRSCode)) {
+            continue;
+        }
+
+        listTmp.emplace_back(
+            operation::ConcatenatedOperation::createComputeMetadata(
+                {op1->inverse(), op2}, false));
+    }
+
+    // Case (intermediate->source) and (target->intermediate)
+    sql = sqlProlog + "ON v1.source_crs_auth_name = v2.target_crs_auth_name "
+                      "AND v1.source_crs_code = v2.target_crs_code " +
+          joinArea +
+          "WHERE v1.target_crs_auth_name = ? AND v1.target_crs_code = ? "
+          "AND v2.source_crs_auth_name = ? AND v2.source_crs_code = ? ";
+    intermediateWhere =
+        buildIntermediateWhere(intermediateCRSAuthCodes, "source", "target");
+    res = d->run(sql + additionalWhere + intermediateWhere + orderBy, params);
+    if (discardSuperseded) {
+        res = filterOutSuperseded(std::move(res));
+    }
+    for (const auto &row : res) {
+        const auto &table1 = row[0];
+        const auto &auth_name1 = row[1];
+        const auto &code1 = row[2];
+        // const auto &accuracy1 = row[3];
+        const auto &table2 = row[4];
+        const auto &auth_name2 = row[5];
+        const auto &code2 = row[6];
+        // const auto &accuracy2 = row[7];
+        auto op1 = d->createFactory(auth_name1)
+                       ->createCoordinateOperation(
+                           code1, true, usePROJAlternativeGridNames, table1);
+        if (useIrrelevantPivot(op1, sourceCRSAuthName, sourceCRSCode,
+                               targetCRSAuthName, targetCRSCode)) {
+            continue;
+        }
+        auto op2 = d->createFactory(auth_name2)
+                       ->createCoordinateOperation(
+                           code2, true, usePROJAlternativeGridNames, table2);
+        if (useIrrelevantPivot(op2, sourceCRSAuthName, sourceCRSCode,
+                               targetCRSAuthName, targetCRSCode)) {
+            continue;
+        }
+
+        listTmp.emplace_back(
+            operation::ConcatenatedOperation::createComputeMetadata(
+                {op1->inverse(), op2->inverse()}, false));
+    }
+
+    std::vector<operation::CoordinateOperationNNPtr> list;
+    for (const auto &op : listTmp) {
+        if (!d->rejectOpDueToMissingGrid(op, discardIfMissingGrid)) {
+            list.emplace_back(op);
+        }
+    }
+
+    return list;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns the authority name associated to this factory.
+ * @return name.
+ */
+const std::string &AuthorityFactory::getAuthority() PROJ_CONST_DEFN {
+    return d->authority();
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns the set of authority codes of the given object type.
+ *
+ * @param type Object type.
+ * @param allowDeprecated whether we should return deprecated objects as well.
+ * @return the set of authority codes for spatial reference objects of the given
+ * type
+ * @throw FactoryException
+ */
+std::set<std::string>
+AuthorityFactory::getAuthorityCodes(const ObjectType &type,
+                                    bool allowDeprecated) const {
+    std::string sql;
+    switch (type) {
+    case ObjectType::PRIME_MERIDIAN:
+        sql = "SELECT code FROM prime_meridian WHERE ";
+        break;
+    case ObjectType::ELLIPSOID:
+        sql = "SELECT code FROM ellipsoid WHERE ";
+        break;
+    case ObjectType::DATUM:
+        sql = "SELECT code FROM object_view WHERE table_name IN "
+              "('geodetic_datum', 'vertical_datum') AND ";
+        break;
+    case ObjectType::GEODETIC_REFERENCE_FRAME:
+        sql = "SELECT code FROM geodetic_datum WHERE ";
+        break;
+    case ObjectType::VERTICAL_REFERENCE_FRAME:
+        sql = "SELECT code FROM vertical_datum WHERE ";
+        break;
+    case ObjectType::CRS:
+        sql = "SELECT code FROM crs_view WHERE ";
+        break;
+    case ObjectType::GEODETIC_CRS:
+        sql = "SELECT code FROM geodetic_crs WHERE ";
+        break;
+    case ObjectType::GEOCENTRIC_CRS:
+        sql = "SELECT code FROM geodetic_crs WHERE type = " GEOCENTRIC " AND ";
+        break;
+    case ObjectType::GEOGRAPHIC_CRS:
+        sql = "SELECT code FROM geodetic_crs WHERE type IN (" GEOG_2D
+              "," GEOG_3D ") AND ";
+        break;
+    case ObjectType::GEOGRAPHIC_2D_CRS:
+        sql = "SELECT code FROM geodetic_crs WHERE type = " GEOG_2D " AND ";
+        break;
+    case ObjectType::GEOGRAPHIC_3D_CRS:
+        sql = "SELECT code FROM geodetic_crs WHERE type = " GEOG_3D " AND ";
+        break;
+    case ObjectType::VERTICAL_CRS:
+        sql = "SELECT code FROM vertical_crs WHERE ";
+        break;
+    case ObjectType::PROJECTED_CRS:
+        sql = "SELECT code FROM projected_crs WHERE ";
+        break;
+    case ObjectType::COMPOUND_CRS:
+        sql = "SELECT code FROM compound_crs WHERE ";
+        break;
+    case ObjectType::COORDINATE_OPERATION:
+        sql =
+            "SELECT code FROM coordinate_operation_with_conversion_view WHERE ";
+        break;
+    case ObjectType::CONVERSION:
+        sql = "SELECT code FROM conversion WHERE ";
+        break;
+    case ObjectType::TRANSFORMATION:
+        sql = "SELECT code FROM coordinate_operation_view WHERE table_name != "
+              "'concatenated_operation' AND ";
+        break;
+    case ObjectType::CONCATENATED_OPERATION:
+        sql = "SELECT code FROM concatenated_operation WHERE ";
+        break;
+    }
+
+    sql += "auth_name = ?";
+    if (!allowDeprecated) {
+        sql += " AND deprecated = 0";
+    }
+
+    auto res = d->run(sql, {d->authority()});
+    std::set<std::string> set;
+    for (const auto &row : res) {
+        set.insert(row[0]);
+    }
+    return set;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Gets a description of the object corresponding to a code.
+ *
+ * \note In case of several objects of different types with the same code,
+ * one of them will be arbitrarily selected.
+ *
+ * @param code Object code allocated by authority. (e.g. "4326")
+ * @return description.
+ * @throw NoSuchAuthorityCodeException
+ * @throw FactoryException
+ */
+std::string
+AuthorityFactory::getDescriptionText(const std::string &code) const {
+    auto sql = "SELECT name FROM object_view WHERE auth_name = ? AND code = "
+               "? ORDER BY table_name";
+    auto res = d->runWithCodeParam(sql, code);
+    if (res.empty()) {
+        throw NoSuchAuthorityCodeException("object not found", d->authority(),
+                                           code);
+    }
+    return res.front()[0];
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Gets the official name from a possibly alias name.
+ *
+ * @param aliasedName Alias name.
+ * @param tableName Table name/category. Can help in case of ambiguities.
+ * Or empty otherwise.
+ * @param source Source of the alias. Can help in case of ambiguities.
+ * Or empty otherwise.
+ * @param tryEquivalentNameSpelling whether the comparison of aliasedName with
+ * the alt_name column of the alis_name table should be done with using
+ * metadata::Identifier::isEquivalentName() rather than strict string
+ * comparison;
+ * @param outTableName Table name in which the official name has been found.
+ * @param outAuthName Authority name of the official name that has been found.
+ * @param outCode Code of the official name that has been found.
+ * @return official name (or empty if not found).
+ * @throw FactoryException
+ */
+std::string AuthorityFactory::getOfficialNameFromAlias(
+    const std::string &aliasedName, const std::string &tableName,
+    const std::string &source, bool tryEquivalentNameSpelling,
+    std::string &outTableName, std::string &outAuthName,
+    std::string &outCode) const {
+
+    if (tryEquivalentNameSpelling) {
+        std::string sql(
+            "SELECT table_name, auth_name, code, alt_name FROM alias_name");
+        ListOfParams params;
+        if (!tableName.empty()) {
+            sql += " WHERE table_name = ?";
+            params.push_back(tableName);
+        }
+        if (!source.empty()) {
+            if (!tableName.empty()) {
+                sql += " AND ";
+            } else {
+                sql += " WHERE ";
+            }
+            sql += "source = ?";
+            params.push_back(source);
+        }
+        auto res = d->run(sql, params);
+        if (res.empty()) {
+            return std::string();
+        }
+        for (const auto &row : res) {
+            const auto &alt_name = row[3];
+            if (metadata::Identifier::isEquivalentName(alt_name.c_str(),
+                                                       aliasedName.c_str())) {
+                outTableName = row[0];
+                outAuthName = row[1];
+                outCode = row[2];
+                sql = "SELECT name FROM \"";
+                sql += replaceAll(outTableName, "\"", "\"\"");
+                sql += "\" WHERE auth_name = ? AND code = ?";
+                res = d->run(sql, {outAuthName, outCode});
+                if (res.empty()) { // shouldn't happen normally
+                    return std::string();
+                }
+                return res.front()[0];
+            }
+        }
+        return std::string();
+    } else {
+        std::string sql(
+            "SELECT table_name, auth_name, code FROM alias_name WHERE "
+            "alt_name = ?");
+        ListOfParams params{aliasedName};
+        if (!tableName.empty()) {
+            sql += " AND table_name = ?";
+            params.push_back(tableName);
+        }
+        if (!source.empty()) {
+            sql += " AND source = ?";
+            params.push_back(source);
+        }
+        auto res = d->run(sql, params);
+        if (res.empty()) {
+            return std::string();
+        }
+        const auto &row = res.front();
+        outTableName = row[0];
+        outAuthName = row[1];
+        outCode = row[2];
+        sql = "SELECT name FROM \"";
+        sql += replaceAll(outTableName, "\"", "\"\"");
+        sql += "\" WHERE auth_name = ? AND code = ?";
+        res = d->run(sql, {outAuthName, outCode});
+        if (res.empty()) { // shouldn't happen normally
+            return std::string();
+        }
+        return res.front()[0];
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+static void addToListString(std::string &out, const char *in) {
+    if (!out.empty()) {
+        out += ',';
+    }
+    out += in;
+}
+
+static void addToListStringWithOR(std::string &out, const char *in) {
+    if (!out.empty()) {
+        out += " OR ";
+    }
+    out += in;
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return a list of objects by their name
+ *
+ * @param searchedName Searched name. Must be at least 2 character long.
+ * @param allowedObjectTypes List of object types into which to search. If
+ * empty, all object types will be searched.
+ * @param approximateMatch Whether approximate name identification is allowed.
+ * @param limitResultCount Maximum number of results to return.
+ * Or 0 for unlimited.
+ * @return list of matched objects.
+ * @throw FactoryException
+ */
+std::list<common::IdentifiedObjectNNPtr>
+AuthorityFactory::createObjectsFromName(
+    const std::string &searchedName,
+    const std::vector<ObjectType> &allowedObjectTypes, bool approximateMatch,
+    size_t limitResultCount) const {
+
+    std::string searchedNameWithoutDeprecated(searchedName);
+    bool deprecated = false;
+    if (ends_with(searchedNameWithoutDeprecated, " (deprecated)")) {
+        deprecated = true;
+        searchedNameWithoutDeprecated.resize(
+            searchedNameWithoutDeprecated.size() - strlen(" (deprecated)"));
+    }
+
+    const std::string canonicalizedSearchedName(
+        metadata::Identifier::canonicalizeName(searchedNameWithoutDeprecated));
+    if (canonicalizedSearchedName.size() <= 1) {
+        return {};
+    }
+
+    std::string sql(
+        "SELECT table_name, auth_name, code, name FROM object_view WHERE "
+        "deprecated = ? AND ");
+    ListOfParams params{deprecated ? 1.0 : 0.0};
+    if (!approximateMatch) {
+        sql += "name LIKE ? AND ";
+        params.push_back(searchedNameWithoutDeprecated);
+    }
+    if (d->hasAuthorityRestriction()) {
+        sql += " auth_name = ? AND ";
+        params.emplace_back(d->authority());
+    }
+
+    if (allowedObjectTypes.empty()) {
+        sql += "table_name IN ("
+               "'prime_meridian','ellipsoid','geodetic_datum',"
+               "'vertical_datum','geodetic_crs','projected_crs',"
+               "'vertical_crs','compound_crs','conversion',"
+               "'helmert_transformation','grid_transformation',"
+               "'other_transformation','concatenated_operation'"
+               ")";
+    } else {
+        std::string tableNameList;
+        std::string otherConditions;
+        for (const auto type : allowedObjectTypes) {
+            switch (type) {
+            case ObjectType::PRIME_MERIDIAN:
+                addToListString(tableNameList, "'prime_meridian'");
+                break;
+            case ObjectType::ELLIPSOID:
+                addToListString(tableNameList, "'ellipsoid'");
+                break;
+            case ObjectType::DATUM:
+                addToListString(tableNameList,
+                                "'geodetic_datum','vertical_datum'");
+                break;
+            case ObjectType::GEODETIC_REFERENCE_FRAME:
+                addToListString(tableNameList, "'geodetic_datum'");
+                break;
+            case ObjectType::VERTICAL_REFERENCE_FRAME:
+                addToListString(tableNameList, "'vertical_datum'");
+                break;
+            case ObjectType::CRS:
+                addToListString(tableNameList, "'geodetic_crs','projected_crs',"
+                                               "'vertical_crs','compound_crs'");
+                break;
+            case ObjectType::GEODETIC_CRS:
+                addToListString(tableNameList, "'geodetic_crs'");
+                break;
+            case ObjectType::GEOCENTRIC_CRS:
+                addToListStringWithOR(otherConditions,
+                                      "(table_name = " GEOCENTRIC " AND "
+                                      "type = " GEOCENTRIC ")");
+                break;
+            case ObjectType::GEOGRAPHIC_CRS:
+                addToListStringWithOR(otherConditions,
+                                      "(table_name = 'geodetic_crs' AND "
+                                      "type IN (" GEOG_2D "," GEOG_3D "))");
+                break;
+            case ObjectType::GEOGRAPHIC_2D_CRS:
+                addToListStringWithOR(otherConditions,
+                                      "(table_name = 'geodetic_crs' AND "
+                                      "type = " GEOG_2D ")");
+                break;
+            case ObjectType::GEOGRAPHIC_3D_CRS:
+                addToListStringWithOR(otherConditions,
+                                      "(table_name = 'geodetic_crs' AND "
+                                      "type = " GEOG_3D ")");
+                break;
+            case ObjectType::PROJECTED_CRS:
+                addToListString(tableNameList, "'projected_crs'");
+                break;
+            case ObjectType::VERTICAL_CRS:
+                addToListString(tableNameList, "'vertical_crs'");
+                break;
+            case ObjectType::COMPOUND_CRS:
+                addToListString(tableNameList, "'compound_crs'");
+                break;
+            case ObjectType::COORDINATE_OPERATION:
+                addToListString(tableNameList,
+                                "'conversion','helmert_transformation',"
+                                "'grid_transformation','other_transformation',"
+                                "'concatenated_operation'");
+                break;
+            case ObjectType::CONVERSION:
+                addToListString(tableNameList, "'conversion'");
+                break;
+            case ObjectType::TRANSFORMATION:
+                addToListString(tableNameList,
+                                "'helmert_transformation',"
+                                "'grid_transformation','other_transformation'");
+                break;
+            case ObjectType::CONCATENATED_OPERATION:
+                addToListString(tableNameList, "'concatenated_operation'");
+                break;
+            }
+        }
+        if (!tableNameList.empty()) {
+            sql += "((table_name IN (";
+            sql += tableNameList;
+            sql += "))";
+            if (!otherConditions.empty()) {
+                sql += " OR ";
+                sql += otherConditions;
+            }
+            sql += ')';
+        } else if (!otherConditions.empty()) {
+            sql += "(";
+            sql += otherConditions;
+            sql += ')';
+        }
+    }
+    sql += " ORDER BY length(name), name";
+    if (limitResultCount > 0 &&
+        limitResultCount <
+            static_cast<size_t>(std::numeric_limits<int>::max()) &&
+        !approximateMatch) {
+        sql += " LIMIT ";
+        sql += toString(static_cast<int>(limitResultCount));
+    }
+
+    std::list<common::IdentifiedObjectNNPtr> res;
+
+    // Querying geodetic datum is a super hot path when importing from WKT1
+    // so cache results.
+    if (allowedObjectTypes.size() == 1 &&
+        allowedObjectTypes[0] == ObjectType::GEODETIC_REFERENCE_FRAME &&
+        approximateMatch && d->authority().empty()) {
+        auto &mapCanonicalizeGRFName =
+            d->context()->getPrivate()->getMapCanonicalizeGRFName();
+        if (mapCanonicalizeGRFName.empty()) {
+            auto sqlRes = d->run(sql, params);
+            for (const auto &row : sqlRes) {
+                const auto &name = row[3];
+                const auto canonicalizedName(
+                    metadata::Identifier::canonicalizeName(name));
+                mapCanonicalizeGRFName[canonicalizedName].push_back(row);
+            }
+        }
+        auto iter = mapCanonicalizeGRFName.find(canonicalizedSearchedName);
+        if (iter != mapCanonicalizeGRFName.end()) {
+            const auto &listOfRow = iter->second;
+            for (const auto &row : listOfRow) {
+                const auto &auth_name = row[1];
+                const auto &code = row[2];
+                auto factory = d->createFactory(auth_name);
+                res.emplace_back(factory->createGeodeticDatum(code));
+                if (limitResultCount > 0 && res.size() == limitResultCount) {
+                    break;
+                }
+            }
+        } else {
+            for (const auto &pair : mapCanonicalizeGRFName) {
+                const auto &listOfRow = pair.second;
+                for (const auto &row : listOfRow) {
+                    const auto &name = row[3];
+                    if (approximateMatch) {
+                        bool match =
+                            ci_find(name, searchedNameWithoutDeprecated) !=
+                            std::string::npos;
+                        if (!match) {
+                            const auto &canonicalizedName(pair.first);
+                            match = ci_find(canonicalizedName,
+                                            canonicalizedSearchedName) !=
+                                    std::string::npos;
+                        }
+                        if (!match) {
+                            continue;
+                        }
+                    }
+
+                    const auto &auth_name = row[1];
+                    const auto &code = row[2];
+                    auto factory = d->createFactory(auth_name);
+                    res.emplace_back(factory->createGeodeticDatum(code));
+                    if (limitResultCount > 0 &&
+                        res.size() == limitResultCount) {
+                        break;
+                    }
+                }
+                if (limitResultCount > 0 && res.size() == limitResultCount) {
+                    break;
+                }
+            }
+        }
+    } else {
+        auto sqlRes = d->run(sql, params);
+        for (const auto &row : sqlRes) {
+            const auto &name = row[3];
+            if (approximateMatch) {
+                bool match = ci_find(name, searchedNameWithoutDeprecated) !=
+                             std::string::npos;
+                if (!match) {
+                    const auto canonicalizedName(
+                        metadata::Identifier::canonicalizeName(name));
+                    match =
+                        ci_find(canonicalizedName, canonicalizedSearchedName) !=
+                        std::string::npos;
+                }
+                if (!match) {
+                    continue;
+                }
+            }
+            const auto &table_name = row[0];
+            const auto &auth_name = row[1];
+            const auto &code = row[2];
+            auto factory = d->createFactory(auth_name);
+            if (table_name == "prime_meridian") {
+                res.emplace_back(factory->createPrimeMeridian(code));
+            } else if (table_name == "ellipsoid") {
+                res.emplace_back(factory->createEllipsoid(code));
+            } else if (table_name == "geodetic_datum") {
+                res.emplace_back(factory->createGeodeticDatum(code));
+            } else if (table_name == "vertical_datum") {
+                res.emplace_back(factory->createVerticalDatum(code));
+            } else if (table_name == "geodetic_crs") {
+                res.emplace_back(factory->createGeodeticCRS(code));
+            } else if (table_name == "projected_crs") {
+                res.emplace_back(factory->createProjectedCRS(code));
+            } else if (table_name == "vertical_crs") {
+                res.emplace_back(factory->createVerticalCRS(code));
+            } else if (table_name == "compound_crs") {
+                res.emplace_back(factory->createCompoundCRS(code));
+            } else if (table_name == "conversion") {
+                res.emplace_back(factory->createConversion(code));
+            } else if (table_name == "grid_transformation" ||
+                       table_name == "helmert_transformation" ||
+                       table_name == "other_transformation" ||
+                       table_name == "concatenated_operation") {
+                res.emplace_back(
+                    factory->createCoordinateOperation(code, true));
+            } else {
+                assert(false);
+            }
+            if (limitResultCount > 0 && res.size() == limitResultCount) {
+                break;
+            }
+        }
+    }
+
+    if (res.empty() && !deprecated) {
+        return createObjectsFromName(searchedName + " (deprecated)",
+                                     allowedObjectTypes, approximateMatch,
+                                     limitResultCount);
+    }
+
+    auto sortLambda = [](const common::IdentifiedObjectNNPtr &a,
+                         const common::IdentifiedObjectNNPtr &b) {
+        const auto &aName = a->nameStr();
+        const auto &bName = b->nameStr();
+        if (aName.size() < bName.size()) {
+            return true;
+        }
+        if (aName.size() > bName.size()) {
+            return false;
+        }
+
+        const auto &aIds = a->identifiers();
+        const auto &bIds = b->identifiers();
+        if (aIds.size() < bIds.size()) {
+            return true;
+        }
+        if (aIds.size() > bIds.size()) {
+            return false;
+        }
+        for (size_t idx = 0; idx < aIds.size(); idx++) {
+            const auto &aCodeSpace = *aIds[idx]->codeSpace();
+            const auto &bCodeSpace = *bIds[idx]->codeSpace();
+            const auto codeSpaceComparison = aCodeSpace.compare(bCodeSpace);
+            if (codeSpaceComparison < 0) {
+                return true;
+            }
+            if (codeSpaceComparison > 0) {
+                return false;
+            }
+            const auto &aCode = aIds[idx]->code();
+            const auto &bCode = bIds[idx]->code();
+            const auto codeComparison = aCode.compare(bCode);
+            if (codeComparison < 0) {
+                return true;
+            }
+            if (codeComparison > 0) {
+                return false;
+            }
+        }
+        return strcmp(typeid(a.get()).name(), typeid(b.get()).name()) < 0;
+    };
+
+    res.sort(sortLambda);
+
+    return res;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return a list of area of use from their name
+ *
+ * @param name Searched name.
+ * @param approximateMatch Whether approximate name identification is allowed.
+ * @return list of (auth_name, code) of matched objects.
+ * @throw FactoryException
+ */
+std::list<std::pair<std::string, std::string>>
+AuthorityFactory::listAreaOfUseFromName(const std::string &name,
+                                        bool approximateMatch) const {
+    std::string sql(
+        "SELECT auth_name, code FROM area WHERE deprecated = 0 AND ");
+    ListOfParams params;
+    if (d->hasAuthorityRestriction()) {
+        sql += " auth_name = ? AND ";
+        params.emplace_back(d->authority());
+    }
+    sql += "name LIKE ?";
+    if (!approximateMatch) {
+        params.push_back(name);
+    } else {
+        params.push_back('%' + name + '%');
+    }
+    auto sqlRes = d->run(sql, params);
+    std::list<std::pair<std::string, std::string>> res;
+    for (const auto &row : sqlRes) {
+        res.emplace_back(row[0], row[1]);
+    }
+    return res;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+std::list<datum::EllipsoidNNPtr> AuthorityFactory::createEllipsoidFromExisting(
+    const datum::EllipsoidNNPtr &ellipsoid) const {
+    std::string sql(
+        "SELECT auth_name, code FROM ellipsoid WHERE "
+        "abs(semi_major_axis - ?) < 1e-10 * abs(semi_major_axis) AND "
+        "((semi_minor_axis IS NOT NULL AND "
+        "abs(semi_minor_axis - ?) < 1e-10 * abs(semi_minor_axis)) OR "
+        "((inv_flattening IS NOT NULL AND "
+        "abs(inv_flattening - ?) < 1e-10 * abs(inv_flattening))))");
+    ListOfParams params{ellipsoid->semiMajorAxis().getSIValue(),
+                        ellipsoid->computeSemiMinorAxis().getSIValue(),
+                        ellipsoid->computedInverseFlattening()};
+    auto sqlRes = d->run(sql, params);
+    std::list<datum::EllipsoidNNPtr> res;
+    for (const auto &row : sqlRes) {
+        const auto &auth_name = row[0];
+        const auto &code = row[1];
+        res.emplace_back(d->createFactory(auth_name)->createEllipsoid(code));
+    }
+    return res;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+std::list<crs::GeodeticCRSNNPtr> AuthorityFactory::createGeodeticCRSFromDatum(
+    const std::string &datum_auth_name, const std::string &datum_code,
+    const std::string &geodetic_crs_type) const {
+    std::string sql(
+        "SELECT auth_name, code FROM geodetic_crs WHERE "
+        "datum_auth_name = ? AND datum_code = ? AND deprecated = 0");
+    ListOfParams params{datum_auth_name, datum_code};
+    if (d->hasAuthorityRestriction()) {
+        sql += " AND auth_name = ?";
+        params.emplace_back(d->authority());
+    }
+    if (!geodetic_crs_type.empty()) {
+        sql += " AND type = ?";
+        params.emplace_back(geodetic_crs_type);
+    }
+    auto sqlRes = d->run(sql, params);
+    std::list<crs::GeodeticCRSNNPtr> res;
+    for (const auto &row : sqlRes) {
+        const auto &auth_name = row[0];
+        const auto &code = row[1];
+        res.emplace_back(d->createFactory(auth_name)->createGeodeticCRS(code));
+    }
+    return res;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+std::list<crs::GeodeticCRSNNPtr>
+AuthorityFactory::createGeodeticCRSFromEllipsoid(
+    const std::string &ellipsoid_auth_name, const std::string &ellipsoid_code,
+    const std::string &geodetic_crs_type) const {
+    std::string sql(
+        "SELECT geodetic_crs.auth_name, geodetic_crs.code FROM geodetic_crs "
+        "JOIN geodetic_datum ON "
+        "geodetic_crs.datum_auth_name = geodetic_datum.auth_name AND "
+        "geodetic_crs.datum_code = geodetic_datum.code WHERE "
+        "geodetic_datum.ellipsoid_auth_name = ? AND "
+        "geodetic_datum.ellipsoid_code = ? AND "
+        "geodetic_datum.deprecated = 0 AND "
+        "geodetic_crs.deprecated = 0");
+    ListOfParams params{ellipsoid_auth_name, ellipsoid_code};
+    if (d->hasAuthorityRestriction()) {
+        sql += " AND geodetic_crs.auth_name = ?";
+        params.emplace_back(d->authority());
+    }
+    if (!geodetic_crs_type.empty()) {
+        sql += " AND geodetic_crs.type = ?";
+        params.emplace_back(geodetic_crs_type);
+    }
+    auto sqlRes = d->run(sql, params);
+    std::list<crs::GeodeticCRSNNPtr> res;
+    for (const auto &row : sqlRes) {
+        const auto &auth_name = row[0];
+        const auto &code = row[1];
+        res.emplace_back(d->createFactory(auth_name)->createGeodeticCRS(code));
+    }
+    return res;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static std::string buildSqlLookForAuthNameCode(
+    const std::list<std::pair<crs::CRSNNPtr, int>> &list, ListOfParams &params,
+    const char *prefixField) {
+    std::string sql("(");
+
+    std::set<std::string> authorities;
+    for (const auto &crs : list) {
+        const auto &ids = crs.first->identifiers();
+        if (!ids.empty()) {
+            authorities.insert(*(ids[0]->codeSpace()));
+        }
+    }
+    bool firstAuth = true;
+    for (const auto &auth_name : authorities) {
+        if (!firstAuth) {
+            sql += " OR ";
+        }
+        firstAuth = false;
+        sql += "( ";
+        sql += prefixField;
+        sql += "auth_name = ? AND ";
+        sql += prefixField;
+        sql += "code IN (";
+        params.emplace_back(auth_name);
+        bool firstGeodCRSForAuth = true;
+        for (const auto &crs : list) {
+            const auto &ids = crs.first->identifiers();
+            if (!ids.empty() && *(ids[0]->codeSpace()) == auth_name) {
+                if (!firstGeodCRSForAuth) {
+                    sql += ',';
+                }
+                firstGeodCRSForAuth = false;
+                sql += '?';
+                params.emplace_back(ids[0]->code());
+            }
+        }
+        sql += "))";
+    }
+    sql += ')';
+    return sql;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+std::list<crs::ProjectedCRSNNPtr>
+AuthorityFactory::createProjectedCRSFromExisting(
+    const crs::ProjectedCRSNNPtr &crs) const {
+    std::list<crs::ProjectedCRSNNPtr> res;
+
+    const auto &conv = crs->derivingConversionRef();
+    const auto &method = conv->method();
+    const auto methodEPSGCode = method->getEPSGCode();
+    if (methodEPSGCode == 0) {
+        return res;
+    }
+
+    auto lockedThisFactory(d->getSharedFromThis());
+    assert(lockedThisFactory);
+    const auto &baseCRS(crs->baseCRS());
+    auto candidatesGeodCRS = baseCRS->crs::CRS::identify(lockedThisFactory);
+    auto geogCRS = dynamic_cast<const crs::GeographicCRS *>(baseCRS.get());
+    if (geogCRS) {
+        const auto axisOrder = geogCRS->coordinateSystem()->axisOrder();
+        if (axisOrder == cs::EllipsoidalCS::AxisOrder::LONG_EAST_LAT_NORTH ||
+            axisOrder == cs::EllipsoidalCS::AxisOrder::LAT_NORTH_LONG_EAST) {
+            const auto &unit =
+                geogCRS->coordinateSystem()->axisList()[0]->unit();
+            auto otherOrderGeogCRS = crs::GeographicCRS::create(
+                util::PropertyMap().set(common::IdentifiedObject::NAME_KEY,
+                                        geogCRS->nameStr()),
+                geogCRS->datum(), geogCRS->datumEnsemble(),
+                axisOrder == cs::EllipsoidalCS::AxisOrder::LONG_EAST_LAT_NORTH
+                    ? cs::EllipsoidalCS::createLatitudeLongitude(unit)
+                    : cs::EllipsoidalCS::createLongitudeLatitude(unit));
+            auto otherCandidatesGeodCRS =
+                otherOrderGeogCRS->crs::CRS::identify(lockedThisFactory);
+            candidatesGeodCRS.insert(candidatesGeodCRS.end(),
+                                     otherCandidatesGeodCRS.begin(),
+                                     otherCandidatesGeodCRS.end());
+        }
+    }
+
+    std::string sql(
+        "SELECT projected_crs.auth_name, projected_crs.code FROM projected_crs "
+        "JOIN conversion ON "
+        "projected_crs.conversion_auth_name = conversion.auth_name AND "
+        "projected_crs.conversion_code = conversion.code WHERE "
+        "projected_crs.deprecated = 0 AND ");
+    ListOfParams params;
+    if (!candidatesGeodCRS.empty()) {
+        sql += buildSqlLookForAuthNameCode(candidatesGeodCRS, params,
+                                           "projected_crs.geodetic_crs_");
+        sql += " AND ";
+    }
+    sql += "conversion.method_auth_name = 'EPSG' AND "
+           "conversion.method_code = ?";
+    params.emplace_back(toString(methodEPSGCode));
+    if (d->hasAuthorityRestriction()) {
+        sql += " AND projected_crs.auth_name = ?";
+        params.emplace_back(d->authority());
+    }
+
+    int iParam = 1;
+    for (const auto &genOpParamvalue : conv->parameterValues()) {
+        auto opParamvalue =
+            dynamic_cast<const operation::OperationParameterValue *>(
+                genOpParamvalue.get());
+        if (!opParamvalue) {
+            break;
+        }
+        const auto paramEPSGCode = opParamvalue->parameter()->getEPSGCode();
+        const auto &parameterValue = opParamvalue->parameterValue();
+        if (!(paramEPSGCode > 0 &&
+              parameterValue->type() ==
+                  operation::ParameterValue::Type::MEASURE)) {
+            break;
+        }
+        const auto &measure = parameterValue->value();
+        const auto &unit = measure.unit();
+        if (unit == common::UnitOfMeasure::DEGREE &&
+            geogCRS->coordinateSystem()->axisList()[0]->unit() == unit) {
+            const auto iParamAsStr(toString(iParam));
+            sql += " AND conversion.param";
+            sql += iParamAsStr;
+            sql += "_code = ? AND conversion.param";
+            sql += iParamAsStr;
+            sql += "_auth_name = 'EPSG' AND conversion.param";
+            sql += iParamAsStr;
+            sql += "_value BETWEEN ? AND ?";
+            // As angles might be expressed with the odd unit EPSG:9110
+            // "sexagesimal DMS", we have to provide a broad range
+            params.emplace_back(toString(paramEPSGCode));
+            params.emplace_back(measure.value() - 1);
+            params.emplace_back(measure.value() + 1);
+        }
+        iParam++;
+    }
+    auto sqlRes = d->run(sql, params);
+
+    params.clear();
+
+    sql = "SELECT auth_name, code FROM projected_crs WHERE "
+          "deprecated = 0 AND conversion_auth_name IS NULL AND ";
+    if (!candidatesGeodCRS.empty()) {
+        sql += buildSqlLookForAuthNameCode(candidatesGeodCRS, params,
+                                           "geodetic_crs_");
+        sql += " AND ";
+    }
+
+    const auto escapeLikeStr = [](const std::string &str) {
+        return replaceAll(replaceAll(replaceAll(str, "\\", "\\\\"), "_", "\\_"),
+                          "%", "\\%");
+    };
+
+    const auto ellpsSemiMajorStr =
+        toString(baseCRS->ellipsoid()->semiMajorAxis().getSIValue(), 10);
+
+    sql += "(text_definition LIKE ? ESCAPE '\\'";
+
+    // WKT2 definition
+    {
+        std::string patternVal("%");
+
+        patternVal += ',';
+        patternVal += ellpsSemiMajorStr;
+        patternVal += '%';
+
+        patternVal += escapeLikeStr(method->nameStr());
+        patternVal += '%';
+
+        params.emplace_back(patternVal);
+    }
+
+    const auto *mapping = getMapping(method.get());
+    if (mapping && mapping->proj_name_main) {
+        sql += " OR (text_definition LIKE ? AND (text_definition LIKE ?";
+
+        std::string patternVal("%");
+        patternVal += "proj=";
+        patternVal += mapping->proj_name_main;
+        patternVal += '%';
+        params.emplace_back(patternVal);
+
+        // could be a= or R=
+        patternVal = "%=";
+        patternVal += ellpsSemiMajorStr;
+        patternVal += '%';
+        params.emplace_back(patternVal);
+
+        std::string projEllpsName;
+        std::string ellpsName;
+        if (baseCRS->ellipsoid()->lookForProjWellKnownEllps(projEllpsName,
+                                                            ellpsName)) {
+            sql += " OR text_definition LIKE ?";
+            // Could be ellps= or datum=
+            patternVal = "%=";
+            patternVal += projEllpsName;
+            patternVal += '%';
+            params.emplace_back(patternVal);
+        }
+
+        sql += "))";
+    }
+
+    // WKT1_GDAL definition
+    const char *wkt1GDALMethodName = conv->getWKT1GDALMethodName();
+    if (wkt1GDALMethodName) {
+        sql += " OR text_definition LIKE ? ESCAPE '\\'";
+        std::string patternVal("%");
+
+        patternVal += ',';
+        patternVal += ellpsSemiMajorStr;
+        patternVal += '%';
+
+        patternVal += escapeLikeStr(wkt1GDALMethodName);
+        patternVal += '%';
+
+        params.emplace_back(patternVal);
+    }
+
+    // WKT1_ESRI definition
+    const char *esriMethodName = conv->getESRIMethodName();
+    if (esriMethodName) {
+        sql += " OR text_definition LIKE ? ESCAPE '\\'";
+        std::string patternVal("%");
+
+        patternVal += ',';
+        patternVal += ellpsSemiMajorStr;
+        patternVal += '%';
+
+        patternVal += escapeLikeStr(esriMethodName);
+        patternVal += '%';
+
+        auto fe =
+            &conv->parameterValueMeasure(EPSG_CODE_PARAMETER_FALSE_EASTING);
+        if (*fe == Measure()) {
+            fe = &conv->parameterValueMeasure(
+                EPSG_CODE_PARAMETER_EASTING_FALSE_ORIGIN);
+        }
+        if (!(*fe == Measure())) {
+            patternVal += "PARAMETER[\"False\\_Easting\",";
+            patternVal +=
+                toString(fe->convertToUnit(
+                             crs->coordinateSystem()->axisList()[0]->unit()),
+                         10);
+            patternVal += '%';
+        }
+
+        auto lat = &conv->parameterValueMeasure(
+            EPSG_NAME_PARAMETER_LATITUDE_OF_NATURAL_ORIGIN);
+        if (*lat == Measure()) {
+            lat = &conv->parameterValueMeasure(
+                EPSG_NAME_PARAMETER_LATITUDE_FALSE_ORIGIN);
+        }
+        if (!(*lat == Measure())) {
+            patternVal += "PARAMETER[\"Latitude\\_Of\\_Origin\",";
+            const auto &angularUnit =
+                dynamic_cast<crs::GeographicCRS *>(crs->baseCRS().get())
+                    ? crs->baseCRS()->coordinateSystem()->axisList()[0]->unit()
+                    : UnitOfMeasure::DEGREE;
+            patternVal += toString(lat->convertToUnit(angularUnit), 10);
+            patternVal += '%';
+        }
+
+        params.emplace_back(patternVal);
+    }
+    sql += ")";
+    if (d->hasAuthorityRestriction()) {
+        sql += " AND auth_name = ?";
+        params.emplace_back(d->authority());
+    }
+
+    auto sqlRes2 = d->run(sql, params);
+
+    if (sqlRes.size() <= 200) {
+        for (const auto &row : sqlRes) {
+            const auto &auth_name = row[0];
+            const auto &code = row[1];
+            res.emplace_back(
+                d->createFactory(auth_name)->createProjectedCRS(code));
+        }
+    }
+    if (sqlRes2.size() <= 200) {
+        for (const auto &row : sqlRes2) {
+            const auto &auth_name = row[0];
+            const auto &code = row[1];
+            res.emplace_back(
+                d->createFactory(auth_name)->createProjectedCRS(code));
+        }
+    }
+
+    return res;
+}
+
+// ---------------------------------------------------------------------------
+
+std::list<crs::CompoundCRSNNPtr>
+AuthorityFactory::createCompoundCRSFromExisting(
+    const crs::CompoundCRSNNPtr &crs) const {
+    std::list<crs::CompoundCRSNNPtr> res;
+
+    auto lockedThisFactory(d->getSharedFromThis());
+    assert(lockedThisFactory);
+
+    const auto &components = crs->componentReferenceSystems();
+    if (components.size() != 2) {
+        return res;
+    }
+    auto candidatesHorizCRS = components[0]->identify(lockedThisFactory);
+    auto candidatesVertCRS = components[1]->identify(lockedThisFactory);
+    if (candidatesHorizCRS.empty() && candidatesVertCRS.empty()) {
+        return res;
+    }
+
+    std::string sql("SELECT auth_name, code FROM compound_crs WHERE "
+                    "deprecated = 0 AND ");
+    ListOfParams params;
+    bool addAnd = false;
+    if (!candidatesHorizCRS.empty()) {
+        sql += buildSqlLookForAuthNameCode(candidatesHorizCRS, params,
+                                           "horiz_crs_");
+        addAnd = true;
+    }
+    if (!candidatesVertCRS.empty()) {
+        if (addAnd) {
+            sql += " AND ";
+        }
+        sql += buildSqlLookForAuthNameCode(candidatesVertCRS, params,
+                                           "vertical_crs_");
+        addAnd = true;
+    }
+    if (d->hasAuthorityRestriction()) {
+        if (addAnd) {
+            sql += " AND ";
+        }
+        sql += "auth_name = ?";
+        params.emplace_back(d->authority());
+    }
+
+    auto sqlRes = d->run(sql, params);
+    for (const auto &row : sqlRes) {
+        const auto &auth_name = row[0];
+        const auto &code = row[1];
+        res.emplace_back(d->createFactory(auth_name)->createCompoundCRS(code));
+    }
+    return res;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+FactoryException::FactoryException(const char *message) : Exception(message) {}
+
+// ---------------------------------------------------------------------------
+
+FactoryException::FactoryException(const std::string &message)
+    : Exception(message) {}
+
+// ---------------------------------------------------------------------------
+
+FactoryException::~FactoryException() = default;
+
+// ---------------------------------------------------------------------------
+
+FactoryException::FactoryException(const FactoryException &) = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+struct NoSuchAuthorityCodeException::Private {
+    std::string authority_;
+    std::string code_;
+
+    Private(const std::string &authority, const std::string &code)
+        : authority_(authority), code_(code) {}
+};
+
+// ---------------------------------------------------------------------------
+
+NoSuchAuthorityCodeException::NoSuchAuthorityCodeException(
+    const std::string &message, const std::string &authority,
+    const std::string &code)
+    : FactoryException(message),
+      d(internal::make_unique<Private>(authority, code)) {}
+
+// ---------------------------------------------------------------------------
+
+NoSuchAuthorityCodeException::~NoSuchAuthorityCodeException() = default;
+
+// ---------------------------------------------------------------------------
+
+NoSuchAuthorityCodeException::NoSuchAuthorityCodeException(
+    const NoSuchAuthorityCodeException &other)
+    : FactoryException(other), d(internal::make_unique<Private>(*(other.d))) {}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns authority name. */
+const std::string &NoSuchAuthorityCodeException::getAuthority() const {
+    return d->authority_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns authority code. */
+const std::string &NoSuchAuthorityCodeException::getAuthorityCode() const {
+    return d->code_;
+}
+
+// ---------------------------------------------------------------------------
+
+} // namespace io
+NS_PROJ_END
diff --git a/src/iso19111/internal.cpp b/src/iso19111/internal.cpp
new file mode 100644
index 00000000..c43605d1
--- /dev/null
+++ b/src/iso19111/internal.cpp
@@ -0,0 +1,374 @@
+/******************************************************************************
+ *
+ * Project:  PROJ
+ * Purpose:  ISO19111:2018 implementation
+ * Author:   Even Rouault <even dot rouault at spatialys dot com>
+ *
+ ******************************************************************************
+ * Copyright (c) 2018, Even Rouault <even dot rouault at spatialys dot com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ ****************************************************************************/
+
+#ifndef FROM_PROJ_CPP
+#define FROM_PROJ_CPP
+#endif
+
+#include "proj/internal/internal.hpp"
+
+#include <cstdint>
+#include <cstring>
+#ifdef _MSC_VER
+#include <string.h>
+#else
+#include <strings.h>
+#endif
+#include <exception>
+#include <iomanip> // std::setprecision
+#include <locale>
+#include <sstream> // std::istringstream and std::ostringstream
+#include <string>
+
+#include "sqlite3.h"
+
+NS_PROJ_START
+
+namespace internal {
+
+// ---------------------------------------------------------------------------
+
+/**
+ * Replace all occurrences of before with after.
+ */
+std::string replaceAll(const std::string &str, const std::string &before,
+                       const std::string &after) {
+    std::string ret(str);
+    const size_t nBeforeSize = before.size();
+    const size_t nAfterSize = after.size();
+    if (nBeforeSize) {
+        size_t nStartPos = 0;
+        while ((nStartPos = ret.find(before, nStartPos)) != std::string::npos) {
+            ret.replace(nStartPos, nBeforeSize, after);
+            nStartPos += nAfterSize;
+        }
+    }
+    return ret;
+}
+
+// ---------------------------------------------------------------------------
+
+inline static bool EQUALN(const char *a, const char *b, size_t size) {
+#ifdef _MSC_VER
+    return _strnicmp(a, b, size) == 0;
+#else
+    return strncasecmp(a, b, size) == 0;
+#endif
+}
+
+/**
+ * Case-insensitive equality test
+ */
+bool ci_equal(const std::string &a, const std::string &b) noexcept {
+    const auto size = a.size();
+    if (size != b.size()) {
+        return false;
+    }
+    return EQUALN(a.c_str(), b.c_str(), size);
+}
+
+bool ci_equal(const std::string &a, const char *b) noexcept {
+    const auto size = a.size();
+    if (size != strlen(b)) {
+        return false;
+    }
+    return EQUALN(a.c_str(), b, size);
+}
+
+bool ci_equal(const char *a, const char *b) noexcept {
+    const auto size = strlen(a);
+    if (size != strlen(b)) {
+        return false;
+    }
+    return EQUALN(a, b, size);
+}
+
+// ---------------------------------------------------------------------------
+
+bool ci_less(const std::string &a, const std::string &b) noexcept {
+#ifdef _MSC_VER
+    return _stricmp(a.c_str(), b.c_str()) < 0;
+#else
+    return strcasecmp(a.c_str(), b.c_str()) < 0;
+#endif
+}
+
+// ---------------------------------------------------------------------------
+
+/**
+ * Convert to lower case.
+ */
+
+std::string tolower(const std::string &str)
+
+{
+    std::string ret(str);
+    for (size_t i = 0; i < ret.size(); i++)
+        ret[i] = static_cast<char>(::tolower(ret[i]));
+    return ret;
+}
+
+// ---------------------------------------------------------------------------
+
+/**
+ * Convert to upper case.
+ */
+
+std::string toupper(const std::string &str)
+
+{
+    std::string ret(str);
+    for (size_t i = 0; i < ret.size(); i++)
+        ret[i] = static_cast<char>(::toupper(ret[i]));
+    return ret;
+}
+
+// ---------------------------------------------------------------------------
+
+/** Strip leading and trailing double quote characters */
+std::string stripQuotes(const std::string &str) {
+    if (str.size() >= 2 && str[0] == '"' && str.back() == '"') {
+        return str.substr(1, str.size() - 2);
+    }
+    return str;
+}
+
+// ---------------------------------------------------------------------------
+
+size_t ci_find(const std::string &str, const char *needle) noexcept {
+    const size_t needleSize = strlen(needle);
+    for (size_t i = 0; i + needleSize <= str.size(); i++) {
+        if (EQUALN(str.c_str() + i, needle, needleSize)) {
+            return i;
+        }
+    }
+    return std::string::npos;
+}
+
+// ---------------------------------------------------------------------------
+
+size_t ci_find(const std::string &str, const std::string &needle,
+               size_t startPos) noexcept {
+    const size_t needleSize = needle.size();
+    for (size_t i = startPos; i + needleSize <= str.size(); i++) {
+        if (EQUALN(str.c_str() + i, needle.c_str(), needleSize)) {
+            return i;
+        }
+    }
+    return std::string::npos;
+}
+
+// ---------------------------------------------------------------------------
+
+/*
+bool starts_with(const std::string &str, const std::string &prefix) noexcept {
+    if (str.size() < prefix.size()) {
+        return false;
+    }
+    return std::memcmp(str.c_str(), prefix.c_str(), prefix.size()) == 0;
+}
+*/
+
+// ---------------------------------------------------------------------------
+
+/*
+bool starts_with(const std::string &str, const char *prefix) noexcept {
+    const size_t prefixSize = std::strlen(prefix);
+    if (str.size() < prefixSize) {
+        return false;
+    }
+    return std::memcmp(str.c_str(), prefix, prefixSize) == 0;
+}
+*/
+
+// ---------------------------------------------------------------------------
+
+bool ci_starts_with(const char *str, const char *prefix) noexcept {
+    const auto str_size = strlen(str);
+    const auto prefix_size = strlen(prefix);
+    if (str_size < prefix_size) {
+        return false;
+    }
+    return EQUALN(str, prefix, prefix_size);
+}
+
+// ---------------------------------------------------------------------------
+
+bool ci_starts_with(const std::string &str,
+                    const std::string &prefix) noexcept {
+    if (str.size() < prefix.size()) {
+        return false;
+    }
+    return EQUALN(str.c_str(), prefix.c_str(), prefix.size());
+}
+
+// ---------------------------------------------------------------------------
+
+bool ends_with(const std::string &str, const std::string &suffix) noexcept {
+    if (str.size() < suffix.size()) {
+        return false;
+    }
+    return std::memcmp(str.c_str() + str.size() - suffix.size(), suffix.c_str(),
+                       suffix.size()) == 0;
+}
+
+// ---------------------------------------------------------------------------
+
+double c_locale_stod(const std::string &s) {
+
+    const auto s_size = s.size();
+    // Fast path
+    if (s_size > 0 && s_size < 15) {
+        std::int64_t acc = 0;
+        std::int64_t div = 1;
+        bool afterDot = false;
+        size_t i = 0;
+        if (s[0] == '-') {
+            ++i;
+            div = -1;
+        } else if (s[0] == '+') {
+            ++i;
+        }
+        for (; i < s_size; ++i) {
+            const auto ch = s[i];
+            if (ch >= '0' && ch <= '9') {
+                acc = acc * 10 + ch - '0';
+                if (afterDot) {
+                    div *= 10;
+                }
+            } else if (ch == '.') {
+                afterDot = true;
+            } else {
+                div = 0;
+            }
+        }
+        if (div) {
+            return static_cast<double>(acc) / div;
+        }
+    }
+
+    std::istringstream iss(s);
+    iss.imbue(std::locale::classic());
+    double d;
+    iss >> d;
+    if (!iss.eof() || iss.fail()) {
+        throw std::invalid_argument("non double value");
+    }
+    return d;
+}
+
+// ---------------------------------------------------------------------------
+
+std::vector<std::string> split(const std::string &str, char separator) {
+    std::vector<std::string> res;
+    size_t lastPos = 0;
+    size_t newPos = 0;
+    while ((newPos = str.find(separator, lastPos)) != std::string::npos) {
+        res.push_back(str.substr(lastPos, newPos - lastPos));
+        lastPos = newPos + 1;
+    }
+    res.push_back(str.substr(lastPos));
+    return res;
+}
+
+// ---------------------------------------------------------------------------
+
+#ifdef _WIN32
+
+// For some reason, sqlite3_snprintf() in the sqlite3 builds used on AppVeyor
+// doesn't round identically to the Unix builds, and thus breaks a number of
+// unit test. So to avoid this, use the stdlib formatting
+
+std::string toString(int val) {
+    std::ostringstream buffer;
+    buffer.imbue(std::locale::classic());
+    buffer << val;
+    return buffer.str();
+}
+
+std::string toString(double val, int precision) {
+    std::ostringstream buffer;
+    buffer.imbue(std::locale::classic());
+    buffer << std::setprecision(precision);
+    buffer << val;
+    auto str = buffer.str();
+    if (precision == 15 && str.find("9999999999") != std::string::npos) {
+        buffer.str("");
+        buffer.clear();
+        buffer << std::setprecision(14);
+        buffer << val;
+        return buffer.str();
+    }
+    return str;
+}
+
+#else
+
+std::string toString(int val) {
+    // use sqlite3 API that is slighly faster than std::ostringstream
+    // with forcing the C locale. sqlite3_snprintf() emulates a C locale.
+    constexpr int BUF_SIZE = 16;
+    char szBuffer[BUF_SIZE];
+    sqlite3_snprintf(BUF_SIZE, szBuffer, "%d", val);
+    return szBuffer;
+}
+
+std::string toString(double val, int precision) {
+    // use sqlite3 API that is slighly faster than std::ostringstream
+    // with forcing the C locale. sqlite3_snprintf() emulates a C locale.
+    constexpr int BUF_SIZE = 32;
+    char szBuffer[BUF_SIZE];
+    sqlite3_snprintf(BUF_SIZE, szBuffer, "%.*g", precision, val);
+    if (precision == 15 && strstr(szBuffer, "9999999999")) {
+        sqlite3_snprintf(BUF_SIZE, szBuffer, "%.14g", val);
+    }
+    return szBuffer;
+}
+
+#endif
+
+// ---------------------------------------------------------------------------
+
+std::string concat(const char *a, const std::string &b) {
+    std::string res(a);
+    res += b;
+    return res;
+}
+
+std::string concat(const char *a, const std::string &b, const char *c) {
+    std::string res(a);
+    res += b;
+    res += c;
+    return res;
+}
+
+// ---------------------------------------------------------------------------
+
+} // namespace internal
+
+NS_PROJ_END
diff --git a/src/iso19111/io.cpp b/src/iso19111/io.cpp
new file mode 100644
index 00000000..fe3680fb
--- /dev/null
+++ b/src/iso19111/io.cpp
@@ -0,0 +1,7501 @@
+/******************************************************************************
+ *
+ * Project:  PROJ
+ * Purpose:  ISO19111:2018 implementation
+ * Author:   Even Rouault <even dot rouault at spatialys dot com>
+ *
+ ******************************************************************************
+ * Copyright (c) 2018, Even Rouault <even dot rouault at spatialys dot com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ ****************************************************************************/
+
+#ifndef FROM_PROJ_CPP
+#define FROM_PROJ_CPP
+#endif
+
+#include <algorithm>
+#include <cassert>
+#include <cctype>
+#include <cmath>
+#include <cstring>
+#include <list>
+#include <locale>
+#include <map>
+#include <set>
+#include <sstream> // std::istringstream
+#include <string>
+#include <utility>
+#include <vector>
+
+#include "proj/common.hpp"
+#include "proj/coordinateoperation.hpp"
+#include "proj/coordinatesystem.hpp"
+#include "proj/crs.hpp"
+#include "proj/datum.hpp"
+#include "proj/io.hpp"
+#include "proj/metadata.hpp"
+#include "proj/util.hpp"
+
+#include "proj/internal/coordinateoperation_internal.hpp"
+#include "proj/internal/coordinatesystem_internal.hpp"
+#include "proj/internal/internal.hpp"
+#include "proj/internal/io_internal.hpp"
+
+#include "proj_constants.h"
+
+#include "pj_wkt1_parser.h"
+#include "pj_wkt2_parser.h"
+
+// PROJ include order is sensitive
+// clang-format off
+#include "proj.h"
+#include "projects.h"
+#include "proj_api.h"
+// clang-format on
+
+using namespace NS_PROJ::common;
+using namespace NS_PROJ::crs;
+using namespace NS_PROJ::cs;
+using namespace NS_PROJ::datum;
+using namespace NS_PROJ::internal;
+using namespace NS_PROJ::metadata;
+using namespace NS_PROJ::operation;
+using namespace NS_PROJ::util;
+
+//! @cond Doxygen_Suppress
+static const std::string emptyString{};
+//! @endcond
+
+#if 0
+namespace dropbox{ namespace oxygen {
+template<> nn<NS_PROJ::io::DatabaseContextPtr>::~nn() = default;
+template<> nn<NS_PROJ::io::AuthorityFactoryPtr>::~nn() = default;
+template<> nn<std::shared_ptr<NS_PROJ::io::IPROJStringExportable>>::~nn() = default;
+template<> nn<std::unique_ptr<NS_PROJ::io::PROJStringFormatter, std::default_delete<NS_PROJ::io::PROJStringFormatter> > >::~nn() = default;
+template<> nn<std::unique_ptr<NS_PROJ::io::WKTFormatter, std::default_delete<NS_PROJ::io::WKTFormatter> > >::~nn() = default;
+template<> nn<std::unique_ptr<NS_PROJ::io::WKTNode, std::default_delete<NS_PROJ::io::WKTNode> > >::~nn() = default;
+}}
+#endif
+
+NS_PROJ_START
+namespace io {
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+IWKTExportable::~IWKTExportable() = default;
+
+// ---------------------------------------------------------------------------
+
+std::string IWKTExportable::exportToWKT(WKTFormatter *formatter) const {
+    _exportToWKT(formatter);
+    return formatter->toString();
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct WKTFormatter::Private {
+    struct Params {
+        WKTFormatter::Convention convention_ = WKTFormatter::Convention::WKT2;
+        WKTFormatter::Version version_ = WKTFormatter::Version::WKT2;
+        bool multiLine_ = true;
+        bool strict_ = true;
+        int indentWidth_ = 4;
+        bool idOnTopLevelOnly_ = false;
+        bool outputAxisOrder_ = false;
+        bool primeMeridianOmittedIfGreenwich_ = false;
+        bool ellipsoidUnitOmittedIfMetre_ = false;
+        bool primeMeridianOrParameterUnitOmittedIfSameAsAxis_ = false;
+        bool forceUNITKeyword_ = false;
+        bool outputCSUnitOnlyOnceIfSame_ = false;
+        bool primeMeridianInDegree_ = false;
+        bool use2018Keywords_ = false;
+        bool useESRIDialect_ = false;
+        OutputAxisRule outputAxis_ = WKTFormatter::OutputAxisRule::YES;
+    };
+    Params params_{};
+    DatabaseContextPtr dbContext_{};
+
+    int indentLevel_ = 0;
+    int level_ = 0;
+    std::vector<bool> stackHasChild_{};
+    std::vector<bool> stackHasId_{false};
+    std::vector<bool> stackEmptyKeyword_{};
+    std::vector<bool> outputUnitStack_{true};
+    std::vector<bool> outputIdStack_{true};
+    std::vector<UnitOfMeasureNNPtr> axisLinearUnitStack_{
+        util::nn_make_shared<UnitOfMeasure>(UnitOfMeasure::METRE)};
+    std::vector<UnitOfMeasureNNPtr> axisAngularUnitStack_{
+        util::nn_make_shared<UnitOfMeasure>(UnitOfMeasure::DEGREE)};
+    bool abridgedTransformation_ = false;
+    bool useDerivingConversion_ = false;
+    std::vector<double> toWGS84Parameters_{};
+    std::string hDatumExtension_{};
+    std::string vDatumExtension_{};
+    std::vector<bool> inversionStack_{false};
+    std::string result_{};
+
+    // cppcheck-suppress functionStatic
+    void addNewLine();
+    void addIndentation();
+    // cppcheck-suppress functionStatic
+    void startNewChild();
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Constructs a new formatter.
+ *
+ * A formatter can be used only once (its internal state is mutated)
+ *
+ * Its default behaviour can be adjusted with the different setters.
+ *
+ * @param convention WKT flavor. Defaults to Convention::WKT2
+ * @param dbContext Database context, to allow queries in it if needed.
+ * This is used for example for WKT1_ESRI output to do name substitutions.
+ *
+ * @return new formatter.
+ */
+WKTFormatterNNPtr WKTFormatter::create(Convention convention,
+                                       // cppcheck-suppress passedByValue
+                                       DatabaseContextPtr dbContext) {
+    auto ret = NN_NO_CHECK(WKTFormatter::make_unique<WKTFormatter>(convention));
+    ret->d->dbContext_ = dbContext;
+    return ret;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Constructs a new formatter from another one.
+ *
+ * A formatter can be used only once (its internal state is mutated)
+ *
+ * Its default behaviour can be adjusted with the different setters.
+ *
+ * @param other source formatter.
+ * @return new formatter.
+ */
+WKTFormatterNNPtr WKTFormatter::create(const WKTFormatterNNPtr &other) {
+    auto f = create(other->d->params_.convention_, other->d->dbContext_);
+    f->d->params_ = other->d->params_;
+    return f;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+WKTFormatter::~WKTFormatter() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Whether to use multi line output or not. */
+WKTFormatter &WKTFormatter::setMultiLine(bool multiLine) noexcept {
+    d->params_.multiLine_ = multiLine;
+    return *this;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Set number of spaces for each indentation level (defaults to 4).
+ */
+WKTFormatter &WKTFormatter::setIndentationWidth(int width) noexcept {
+    d->params_.indentWidth_ = width;
+    return *this;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Set whether AXIS nodes should be output.
+ */
+WKTFormatter &
+WKTFormatter::setOutputAxis(OutputAxisRule outputAxisIn) noexcept {
+    d->params_.outputAxis_ = outputAxisIn;
+    return *this;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Set whether the formatter should operate on strict more or not.
+ *
+ * The default is strit mode, in which case a FormattingException can be thrown.
+ */
+WKTFormatter &WKTFormatter::setStrict(bool strictIn) noexcept {
+    d->params_.strict_ = strictIn;
+    return *this;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns whether the formatter is in strict mode. */
+bool WKTFormatter::isStrict() const noexcept { return d->params_.strict_; }
+
+// ---------------------------------------------------------------------------
+
+/** Returns the WKT string from the formatter. */
+const std::string &WKTFormatter::toString() const {
+    if (d->indentLevel_ > 0 || d->level_ > 0) {
+        // For intermediary nodes, the formatter is in a inconsistent
+        // state.
+        throw FormattingException("toString() called on intermediate nodes");
+    }
+    if (d->axisLinearUnitStack_.size() != 1)
+        throw FormattingException(
+            "Unbalanced pushAxisLinearUnit() / popAxisLinearUnit()");
+    if (d->axisAngularUnitStack_.size() != 1)
+        throw FormattingException(
+            "Unbalanced pushAxisAngularUnit() / popAxisAngularUnit()");
+    if (d->outputIdStack_.size() != 1)
+        throw FormattingException("Unbalanced pushOutputId() / popOutputId()");
+    if (d->outputUnitStack_.size() != 1)
+        throw FormattingException(
+            "Unbalanced pushOutputUnit() / popOutputUnit()");
+
+    return d->result_;
+}
+
+//! @cond Doxygen_Suppress
+
+// ---------------------------------------------------------------------------
+
+WKTFormatter::WKTFormatter(Convention convention)
+    : d(internal::make_unique<Private>()) {
+    d->params_.convention_ = convention;
+    switch (convention) {
+    case Convention::WKT2_2018:
+        d->params_.use2018Keywords_ = true;
+        PROJ_FALLTHROUGH
+    case Convention::WKT2:
+        d->params_.version_ = WKTFormatter::Version::WKT2;
+        d->params_.outputAxisOrder_ = true;
+        break;
+
+    case Convention::WKT2_2018_SIMPLIFIED:
+        d->params_.use2018Keywords_ = true;
+        PROJ_FALLTHROUGH
+    case Convention::WKT2_SIMPLIFIED:
+        d->params_.version_ = WKTFormatter::Version::WKT2;
+        d->params_.idOnTopLevelOnly_ = true;
+        d->params_.outputAxisOrder_ = false;
+        d->params_.primeMeridianOmittedIfGreenwich_ = true;
+        d->params_.ellipsoidUnitOmittedIfMetre_ = true;
+        d->params_.primeMeridianOrParameterUnitOmittedIfSameAsAxis_ = true;
+        d->params_.forceUNITKeyword_ = true;
+        d->params_.outputCSUnitOnlyOnceIfSame_ = true;
+        break;
+
+    case Convention::WKT1_GDAL:
+        d->params_.version_ = WKTFormatter::Version::WKT1;
+        d->params_.outputAxisOrder_ = false;
+        d->params_.forceUNITKeyword_ = true;
+        d->params_.primeMeridianInDegree_ = true;
+        d->params_.outputAxis_ =
+            WKTFormatter::OutputAxisRule::WKT1_GDAL_EPSG_STYLE;
+        break;
+
+    case Convention::WKT1_ESRI:
+        d->params_.version_ = WKTFormatter::Version::WKT1;
+        d->params_.outputAxisOrder_ = false;
+        d->params_.forceUNITKeyword_ = true;
+        d->params_.primeMeridianInDegree_ = true;
+        d->params_.useESRIDialect_ = true;
+        d->params_.multiLine_ = false;
+        d->params_.outputAxis_ = WKTFormatter::OutputAxisRule::NO;
+        break;
+
+    default:
+        assert(false);
+        break;
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+WKTFormatter &WKTFormatter::setOutputId(bool outputIdIn) {
+    if (d->indentLevel_ != 0) {
+        throw Exception(
+            "setOutputId() shall only be called when the stack state is empty");
+    }
+    d->outputIdStack_[0] = outputIdIn;
+    return *this;
+}
+
+// ---------------------------------------------------------------------------
+
+void WKTFormatter::Private::addNewLine() { result_ += '\n'; }
+
+// ---------------------------------------------------------------------------
+
+void WKTFormatter::Private::addIndentation() {
+    result_ += std::string(indentLevel_ * params_.indentWidth_, ' ');
+}
+
+// ---------------------------------------------------------------------------
+
+void WKTFormatter::enter() {
+    if (d->indentLevel_ == 0 && d->level_ == 0) {
+        d->stackHasChild_.push_back(false);
+    }
+    ++d->level_;
+}
+
+// ---------------------------------------------------------------------------
+
+void WKTFormatter::leave() {
+    assert(d->level_ > 0);
+    --d->level_;
+    if (d->indentLevel_ == 0 && d->level_ == 0) {
+        d->stackHasChild_.pop_back();
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+void WKTFormatter::startNode(const std::string &keyword, bool hasId) {
+    if (!d->stackHasChild_.empty()) {
+        d->startNewChild();
+    } else if (!d->result_.empty()) {
+        d->result_ += ',';
+        if (d->params_.multiLine_ && !keyword.empty()) {
+            d->addNewLine();
+        }
+    }
+
+    if (d->params_.multiLine_) {
+        if ((d->indentLevel_ || d->level_) && !keyword.empty()) {
+            if (!d->result_.empty()) {
+                d->addNewLine();
+            }
+            d->addIndentation();
+        }
+    }
+
+    if (!keyword.empty()) {
+        d->result_ += keyword;
+        d->result_ += '[';
+    }
+    d->indentLevel_++;
+    d->stackHasChild_.push_back(false);
+    d->stackEmptyKeyword_.push_back(keyword.empty());
+
+    // Starting from a node that has a ID, we should emit ID nodes for :
+    // - this node
+    // - and for METHOD&PARAMETER nodes in WKT2, unless idOnTopLevelOnly_ is
+    // set.
+    // For WKT2, all other intermediate nodes shouldn't have ID ("not
+    // recommended")
+    if (!d->params_.idOnTopLevelOnly_ && d->indentLevel_ >= 2 &&
+        d->params_.version_ == WKTFormatter::Version::WKT2 &&
+        (keyword == WKTConstants::METHOD ||
+         keyword == WKTConstants::PARAMETER)) {
+        pushOutputId(d->outputIdStack_[0]);
+    } else if (d->indentLevel_ >= 2 &&
+               d->params_.version_ == WKTFormatter::Version::WKT2) {
+        pushOutputId(d->outputIdStack_[0] && !d->stackHasId_.back());
+    } else {
+        pushOutputId(outputId());
+    }
+
+    d->stackHasId_.push_back(hasId || d->stackHasId_.back());
+}
+
+// ---------------------------------------------------------------------------
+
+void WKTFormatter::endNode() {
+    assert(d->indentLevel_ > 0);
+    d->stackHasId_.pop_back();
+    popOutputId();
+    d->indentLevel_--;
+    bool emptyKeyword = d->stackEmptyKeyword_.back();
+    d->stackEmptyKeyword_.pop_back();
+    d->stackHasChild_.pop_back();
+    if (!emptyKeyword)
+        d->result_ += ']';
+}
+
+// ---------------------------------------------------------------------------
+
+WKTFormatter &WKTFormatter::simulCurNodeHasId() {
+    d->stackHasId_.back() = true;
+    return *this;
+}
+
+// ---------------------------------------------------------------------------
+
+void WKTFormatter::Private::startNewChild() {
+    assert(!stackHasChild_.empty());
+    if (stackHasChild_.back()) {
+        result_ += ',';
+    }
+    stackHasChild_.back() = true;
+}
+
+// ---------------------------------------------------------------------------
+
+void WKTFormatter::addQuotedString(const char *str) {
+    addQuotedString(std::string(str));
+}
+
+void WKTFormatter::addQuotedString(const std::string &str) {
+    d->startNewChild();
+    d->result_ += '"';
+    d->result_ += replaceAll(str, "\"", "\"\"");
+    d->result_ += '"';
+}
+
+// ---------------------------------------------------------------------------
+
+void WKTFormatter::add(const std::string &str) {
+    d->startNewChild();
+    d->result_ += str;
+}
+
+// ---------------------------------------------------------------------------
+
+void WKTFormatter::add(int number) {
+    d->startNewChild();
+    d->result_ += internal::toString(number);
+}
+
+// ---------------------------------------------------------------------------
+
+#ifdef __MINGW32__
+static std::string normalizeSerializedString(const std::string &in) {
+    // mingw will output 1e-0xy instead of 1e-xy. Fix that
+    auto pos = in.find("e-0");
+    if (pos == std::string::npos) {
+        return in;
+    }
+    if (pos + 4 < in.size() && isdigit(in[pos + 3]) && isdigit(in[pos + 4])) {
+        return in.substr(0, pos + 2) + in.substr(pos + 3);
+    }
+    return in;
+}
+#else
+static inline std::string normalizeSerializedString(const std::string &in) {
+    return in;
+}
+#endif
+
+// ---------------------------------------------------------------------------
+
+void WKTFormatter::add(double number, int precision) {
+    d->startNewChild();
+    if (number == 0.0) {
+        if (d->params_.useESRIDialect_) {
+            d->result_ += "0.0";
+        } else {
+            d->result_ += '0';
+        }
+    } else {
+        std::string val(
+            normalizeSerializedString(internal::toString(number, precision)));
+        d->result_ += val;
+        if (d->params_.useESRIDialect_ && val.find('.') == std::string::npos) {
+            d->result_ += ".0";
+        }
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+void WKTFormatter::pushOutputUnit(bool outputUnitIn) {
+    d->outputUnitStack_.push_back(outputUnitIn);
+}
+
+// ---------------------------------------------------------------------------
+
+void WKTFormatter::popOutputUnit() { d->outputUnitStack_.pop_back(); }
+
+// ---------------------------------------------------------------------------
+
+bool WKTFormatter::outputUnit() const { return d->outputUnitStack_.back(); }
+
+// ---------------------------------------------------------------------------
+
+void WKTFormatter::pushOutputId(bool outputIdIn) {
+    d->outputIdStack_.push_back(outputIdIn);
+}
+
+// ---------------------------------------------------------------------------
+
+void WKTFormatter::popOutputId() { d->outputIdStack_.pop_back(); }
+
+// ---------------------------------------------------------------------------
+
+bool WKTFormatter::outputId() const {
+    return !d->params_.useESRIDialect_ && d->outputIdStack_.back();
+}
+
+// ---------------------------------------------------------------------------
+
+void WKTFormatter::pushAxisLinearUnit(const UnitOfMeasureNNPtr &unit) {
+    d->axisLinearUnitStack_.push_back(unit);
+}
+// ---------------------------------------------------------------------------
+
+void WKTFormatter::popAxisLinearUnit() { d->axisLinearUnitStack_.pop_back(); }
+
+// ---------------------------------------------------------------------------
+
+const UnitOfMeasureNNPtr &WKTFormatter::axisLinearUnit() const {
+    return d->axisLinearUnitStack_.back();
+}
+
+// ---------------------------------------------------------------------------
+
+void WKTFormatter::pushAxisAngularUnit(const UnitOfMeasureNNPtr &unit) {
+    d->axisAngularUnitStack_.push_back(unit);
+}
+// ---------------------------------------------------------------------------
+
+void WKTFormatter::popAxisAngularUnit() { d->axisAngularUnitStack_.pop_back(); }
+
+// ---------------------------------------------------------------------------
+
+const UnitOfMeasureNNPtr &WKTFormatter::axisAngularUnit() const {
+    return d->axisAngularUnitStack_.back();
+}
+
+// ---------------------------------------------------------------------------
+
+WKTFormatter::OutputAxisRule WKTFormatter::outputAxis() const {
+    return d->params_.outputAxis_;
+}
+
+// ---------------------------------------------------------------------------
+
+bool WKTFormatter::outputAxisOrder() const {
+    return d->params_.outputAxisOrder_;
+}
+
+// ---------------------------------------------------------------------------
+
+bool WKTFormatter::primeMeridianOmittedIfGreenwich() const {
+    return d->params_.primeMeridianOmittedIfGreenwich_;
+}
+
+// ---------------------------------------------------------------------------
+
+bool WKTFormatter::ellipsoidUnitOmittedIfMetre() const {
+    return d->params_.ellipsoidUnitOmittedIfMetre_;
+}
+
+// ---------------------------------------------------------------------------
+
+bool WKTFormatter::primeMeridianOrParameterUnitOmittedIfSameAsAxis() const {
+    return d->params_.primeMeridianOrParameterUnitOmittedIfSameAsAxis_;
+}
+
+// ---------------------------------------------------------------------------
+
+bool WKTFormatter::outputCSUnitOnlyOnceIfSame() const {
+    return d->params_.outputCSUnitOnlyOnceIfSame_;
+}
+
+// ---------------------------------------------------------------------------
+
+bool WKTFormatter::forceUNITKeyword() const {
+    return d->params_.forceUNITKeyword_;
+}
+
+// ---------------------------------------------------------------------------
+
+bool WKTFormatter::primeMeridianInDegree() const {
+    return d->params_.primeMeridianInDegree_;
+}
+
+// ---------------------------------------------------------------------------
+
+WKTFormatter::Version WKTFormatter::version() const {
+    return d->params_.version_;
+}
+
+// ---------------------------------------------------------------------------
+
+bool WKTFormatter::use2018Keywords() const {
+    return d->params_.use2018Keywords_;
+}
+
+// ---------------------------------------------------------------------------
+
+bool WKTFormatter::useESRIDialect() const { return d->params_.useESRIDialect_; }
+
+// ---------------------------------------------------------------------------
+
+const DatabaseContextPtr &WKTFormatter::databaseContext() const {
+    return d->dbContext_;
+}
+
+// ---------------------------------------------------------------------------
+
+void WKTFormatter::setAbridgedTransformation(bool outputIn) {
+    d->abridgedTransformation_ = outputIn;
+}
+
+// ---------------------------------------------------------------------------
+
+bool WKTFormatter::abridgedTransformation() const {
+    return d->abridgedTransformation_;
+}
+
+// ---------------------------------------------------------------------------
+
+void WKTFormatter::setUseDerivingConversion(bool useDerivingConversionIn) {
+    d->useDerivingConversion_ = useDerivingConversionIn;
+}
+
+// ---------------------------------------------------------------------------
+
+bool WKTFormatter::useDerivingConversion() const {
+    return d->useDerivingConversion_;
+}
+
+// ---------------------------------------------------------------------------
+
+void WKTFormatter::setTOWGS84Parameters(const std::vector<double> &params) {
+    d->toWGS84Parameters_ = params;
+}
+
+// ---------------------------------------------------------------------------
+
+const std::vector<double> &WKTFormatter::getTOWGS84Parameters() const {
+    return d->toWGS84Parameters_;
+}
+
+// ---------------------------------------------------------------------------
+
+void WKTFormatter::setVDatumExtension(const std::string &filename) {
+    d->vDatumExtension_ = filename;
+}
+
+// ---------------------------------------------------------------------------
+
+const std::string &WKTFormatter::getVDatumExtension() const {
+    return d->vDatumExtension_;
+}
+
+// ---------------------------------------------------------------------------
+
+void WKTFormatter::setHDatumExtension(const std::string &filename) {
+    d->hDatumExtension_ = filename;
+}
+
+// ---------------------------------------------------------------------------
+
+const std::string &WKTFormatter::getHDatumExtension() const {
+    return d->hDatumExtension_;
+}
+
+// ---------------------------------------------------------------------------
+
+std::string WKTFormatter::morphNameToESRI(const std::string &name) {
+    std::string ret;
+    bool insertUnderscore = false;
+    // Replace any special character by underscore, except at the beginning
+    // and of the name where those characters are removed.
+    for (char ch : name) {
+        if (ch == '+' || (ch >= '0' && ch <= '9') || (ch >= 'a' && ch <= 'z') ||
+            (ch >= 'A' && ch <= 'Z')) {
+            if (insertUnderscore && !ret.empty()) {
+                ret += '_';
+            }
+            ret += ch;
+            insertUnderscore = false;
+        } else {
+            insertUnderscore = true;
+        }
+    }
+    return ret;
+}
+
+// ---------------------------------------------------------------------------
+
+void WKTFormatter::ingestWKTNode(const WKTNodeNNPtr &node) {
+    startNode(node->value(), true);
+    for (const auto &child : node->children()) {
+        if (!child->children().empty()) {
+            ingestWKTNode(child);
+        } else {
+            add(child->value());
+        }
+    }
+    endNode();
+}
+
+#ifdef unused
+// ---------------------------------------------------------------------------
+
+void WKTFormatter::startInversion() {
+    d->inversionStack_.push_back(!d->inversionStack_.back());
+}
+
+// ---------------------------------------------------------------------------
+
+void WKTFormatter::stopInversion() {
+    assert(!d->inversionStack_.empty());
+    d->inversionStack_.pop_back();
+}
+
+// ---------------------------------------------------------------------------
+
+bool WKTFormatter::isInverted() const { return d->inversionStack_.back(); }
+#endif
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+static WKTNodeNNPtr
+    null_node(NN_NO_CHECK(internal::make_unique<WKTNode>(std::string())));
+
+static inline bool isNull(const WKTNodeNNPtr &node) {
+    return &node == &null_node;
+}
+
+struct WKTNode::Private {
+    std::string value_{};
+    std::vector<WKTNodeNNPtr> children_{};
+
+    explicit Private(const std::string &valueIn) : value_(valueIn) {}
+
+    // cppcheck-suppress functionStatic
+    inline const std::string &value() PROJ_CONST_DEFN { return value_; }
+
+    // cppcheck-suppress functionStatic
+    inline const std::vector<WKTNodeNNPtr> &children() PROJ_CONST_DEFN {
+        return children_;
+    }
+
+    // cppcheck-suppress functionStatic
+    inline size_t childrenSize() PROJ_CONST_DEFN { return children_.size(); }
+
+    // cppcheck-suppress functionStatic
+    const WKTNodeNNPtr &lookForChild(const std::string &childName,
+                                     int occurrence) const noexcept;
+
+    // cppcheck-suppress functionStatic
+    const WKTNodeNNPtr &lookForChild(const std::string &name) const noexcept;
+
+    // cppcheck-suppress functionStatic
+    const WKTNodeNNPtr &lookForChild(const std::string &name,
+                                     const std::string &name2) const noexcept;
+
+    // cppcheck-suppress functionStatic
+    const WKTNodeNNPtr &lookForChild(const std::string &name,
+                                     const std::string &name2,
+                                     const std::string &name3) const noexcept;
+
+    // cppcheck-suppress functionStatic
+    const WKTNodeNNPtr &lookForChild(const std::string &name,
+                                     const std::string &name2,
+                                     const std::string &name3,
+                                     const std::string &name4) const noexcept;
+};
+
+#define GP() getPrivate()
+
+// ---------------------------------------------------------------------------
+
+const WKTNodeNNPtr &WKTNode::Private::lookForChild(const std::string &childName,
+                                                   int occurrence) const
+    noexcept {
+    int occCount = 0;
+    for (const auto &child : children_) {
+        if (ci_equal(child->GP()->value(), childName)) {
+            if (occurrence == occCount) {
+                return child;
+            }
+            occCount++;
+        }
+    }
+    return null_node;
+}
+
+const WKTNodeNNPtr &
+WKTNode::Private::lookForChild(const std::string &name) const noexcept {
+    for (const auto &child : children_) {
+        const auto &v = child->GP()->value();
+        if (ci_equal(v, name)) {
+            return child;
+        }
+    }
+    return null_node;
+}
+
+const WKTNodeNNPtr &
+WKTNode::Private::lookForChild(const std::string &name,
+                               const std::string &name2) const noexcept {
+    for (const auto &child : children_) {
+        const auto &v = child->GP()->value();
+        if (ci_equal(v, name) || ci_equal(v, name2)) {
+            return child;
+        }
+    }
+    return null_node;
+}
+
+const WKTNodeNNPtr &
+WKTNode::Private::lookForChild(const std::string &name,
+                               const std::string &name2,
+                               const std::string &name3) const noexcept {
+    for (const auto &child : children_) {
+        const auto &v = child->GP()->value();
+        if (ci_equal(v, name) || ci_equal(v, name2) || ci_equal(v, name3)) {
+            return child;
+        }
+    }
+    return null_node;
+}
+
+const WKTNodeNNPtr &WKTNode::Private::lookForChild(
+    const std::string &name, const std::string &name2, const std::string &name3,
+    const std::string &name4) const noexcept {
+    for (const auto &child : children_) {
+        const auto &v = child->GP()->value();
+        if (ci_equal(v, name) || ci_equal(v, name2) || ci_equal(v, name3) ||
+            ci_equal(v, name4)) {
+            return child;
+        }
+    }
+    return null_node;
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a WKTNode.
+ *
+ * @param valueIn the name of the node.
+ */
+WKTNode::WKTNode(const std::string &valueIn)
+    : d(internal::make_unique<Private>(valueIn)) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+WKTNode::~WKTNode() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Adds a child to the current node.
+ *
+ * @param child child to add. This should not be a parent of this node.
+ */
+void WKTNode::addChild(WKTNodeNNPtr &&child) {
+    d->children_.push_back(std::move(child));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the (occurrence-1)th sub-node of name childName.
+ *
+ * @param childName name of the child.
+ * @param occurrence occurrence index (starting at 0)
+ * @return the child, or nullptr.
+ */
+const WKTNodePtr &WKTNode::lookForChild(const std::string &childName,
+                                        int occurrence) const noexcept {
+    int occCount = 0;
+    for (const auto &child : d->children_) {
+        if (ci_equal(child->GP()->value(), childName)) {
+            if (occurrence == occCount) {
+                return child;
+            }
+            occCount++;
+        }
+    }
+    return null_node;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the count of children of given name.
+ *
+ * @param childName name of the children to look for.
+ * @return count
+ */
+int WKTNode::countChildrenOfName(const std::string &childName) const noexcept {
+    int occCount = 0;
+    for (const auto &child : d->children_) {
+        if (ci_equal(child->GP()->value(), childName)) {
+            occCount++;
+        }
+    }
+    return occCount;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the value of a node.
+ */
+const std::string &WKTNode::value() const { return d->value_; }
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the children of a node.
+ */
+const std::vector<WKTNodeNNPtr> &WKTNode::children() const {
+    return d->children_;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static size_t skipSpace(const std::string &str, size_t start) {
+    size_t i = start;
+    while (i < str.size() && ::isspace(str[i])) {
+        ++i;
+    }
+    return i;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+// As used in examples of OGC 12-063r5
+static const std::string startPrintedQuote("\xE2\x80\x9C");
+static const std::string endPrintedQuote("\xE2\x80\x9D");
+//! @endcond
+
+WKTNodeNNPtr WKTNode::createFrom(const std::string &wkt, size_t indexStart,
+                                 int recLevel, size_t &indexEnd) {
+    if (recLevel == 16) {
+        throw ParsingException("too many nesting levels");
+    }
+    std::string value;
+    size_t i = skipSpace(wkt, indexStart);
+    if (i == wkt.size()) {
+        throw ParsingException("whitespace only string");
+    }
+    std::string closingStringMarker;
+    bool inString = false;
+
+    for (; i < wkt.size() &&
+           (inString || (wkt[i] != '[' && wkt[i] != '(' && wkt[i] != ',' &&
+                         wkt[i] != ']' && wkt[i] != ')' && !::isspace(wkt[i])));
+         ++i) {
+        if (wkt[i] == '"') {
+            if (!inString) {
+                inString = true;
+                closingStringMarker = "\"";
+            } else if (closingStringMarker == "\"") {
+                if (i + 1 < wkt.size() && wkt[i + 1] == '"') {
+                    i++;
+                } else {
+                    inString = false;
+                    closingStringMarker.clear();
+                }
+            }
+        } else if (i + 3 <= wkt.size() &&
+                   wkt.substr(i, 3) == startPrintedQuote) {
+            if (!inString) {
+                inString = true;
+                closingStringMarker = endPrintedQuote;
+                value += '"';
+                i += 2;
+                continue;
+            }
+        } else if (i + 3 <= wkt.size() &&
+                   closingStringMarker == endPrintedQuote &&
+                   wkt.substr(i, 3) == endPrintedQuote) {
+            inString = false;
+            closingStringMarker.clear();
+            value += '"';
+            i += 2;
+            continue;
+        }
+        value += wkt[i];
+    }
+    i = skipSpace(wkt, i);
+    if (i == wkt.size()) {
+        if (indexStart == 0) {
+            throw ParsingException("missing [");
+        } else {
+            throw ParsingException("missing , or ]");
+        }
+    }
+
+    auto node = NN_NO_CHECK(internal::make_unique<WKTNode>(value));
+
+    if (indexStart > 0) {
+        if (wkt[i] == ',') {
+            indexEnd = i + 1;
+            return node;
+        }
+        if (wkt[i] == ']' || wkt[i] == ')') {
+            indexEnd = i;
+            return node;
+        }
+    }
+    if (wkt[i] != '[' && wkt[i] != '(') {
+        throw ParsingException("missing [");
+    }
+    ++i; // skip [
+    i = skipSpace(wkt, i);
+    while (i < wkt.size() && wkt[i] != ']' && wkt[i] != ')') {
+        size_t indexEndChild;
+        node->addChild(createFrom(wkt, i, recLevel + 1, indexEndChild));
+        assert(indexEndChild > i);
+        i = indexEndChild;
+        i = skipSpace(wkt, i);
+        if (i < wkt.size() && wkt[i] == ',') {
+            ++i;
+            i = skipSpace(wkt, i);
+        }
+    }
+    if (i == wkt.size() || (wkt[i] != ']' && wkt[i] != ')')) {
+        throw ParsingException("missing ]");
+    }
+    indexEnd = i + 1;
+    return node;
+}
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a WKTNode hierarchy from a WKT string.
+ *
+ * @param wkt the WKT string to parse.
+ * @param indexStart the start index in the wkt string.
+ * @throw ParsingException
+ */
+WKTNodeNNPtr WKTNode::createFrom(const std::string &wkt, size_t indexStart) {
+    size_t indexEnd;
+    return createFrom(wkt, indexStart, 0, indexEnd);
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static std::string escapeIfQuotedString(const std::string &str) {
+    if (str.size() > 2 && str[0] == '"' && str.back() == '"') {
+        std::string res("\"");
+        res += replaceAll(str.substr(1, str.size() - 2), "\"", "\"\"");
+        res += '"';
+        return res;
+    } else {
+        return str;
+    }
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return a WKT representation of the tree structure.
+ */
+std::string WKTNode::toString() const {
+    std::string str(escapeIfQuotedString(d->value_));
+    if (!d->children_.empty()) {
+        str += "[";
+        bool first = true;
+        for (auto &child : d->children_) {
+            if (!first) {
+                str += ',';
+            }
+            first = false;
+            str += child->toString();
+        }
+        str += "]";
+    }
+    return str;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct WKTParser::Private {
+    bool strict_ = true;
+    std::list<std::string> warningList_{};
+    std::vector<double> toWGS84Parameters_{};
+    std::string datumPROJ4Grids_{};
+    bool esriStyle_ = false;
+    DatabaseContextPtr dbContext_{};
+
+    static constexpr int MAX_PROPERTY_SIZE = 1024;
+    PropertyMap **properties_{};
+    int propertyCount_ = 0;
+
+    Private() { properties_ = new PropertyMap *[MAX_PROPERTY_SIZE]; }
+
+    ~Private() {
+        for (int i = 0; i < propertyCount_; i++) {
+            delete properties_[i];
+        }
+        delete[] properties_;
+    }
+    Private(const Private &) = delete;
+    Private &operator=(const Private &) = delete;
+
+    void emitRecoverableAssertion(const std::string &errorMsg);
+
+    BaseObjectNNPtr build(const WKTNodeNNPtr &node);
+
+    IdentifierPtr buildId(const WKTNodeNNPtr &node, bool tolerant = true);
+
+    PropertyMap &buildProperties(const WKTNodeNNPtr &node);
+
+    ObjectDomainPtr buildObjectDomain(const WKTNodeNNPtr &node);
+
+    static std::string stripQuotes(const WKTNodeNNPtr &node);
+
+    static double asDouble(const WKTNodeNNPtr &node);
+
+    UnitOfMeasure
+    buildUnit(const WKTNodeNNPtr &node,
+              UnitOfMeasure::Type type = UnitOfMeasure::Type::UNKNOWN);
+
+    UnitOfMeasure buildUnitInSubNode(
+        const WKTNodeNNPtr &node,
+        common::UnitOfMeasure::Type type = UnitOfMeasure::Type::UNKNOWN);
+
+    EllipsoidNNPtr buildEllipsoid(const WKTNodeNNPtr &node);
+
+    PrimeMeridianNNPtr
+    buildPrimeMeridian(const WKTNodeNNPtr &node,
+                       const UnitOfMeasure &defaultAngularUnit);
+
+    optional<std::string> getAnchor(const WKTNodeNNPtr &node);
+
+    static void parseDynamic(const WKTNodeNNPtr &dynamicNode,
+                             double &frameReferenceEpoch,
+                             util::optional<std::string> &modelName);
+
+    GeodeticReferenceFrameNNPtr
+    buildGeodeticReferenceFrame(const WKTNodeNNPtr &node,
+                                const PrimeMeridianNNPtr &primeMeridian,
+                                const WKTNodeNNPtr &dynamicNode);
+
+    DatumEnsembleNNPtr buildDatumEnsemble(const WKTNodeNNPtr &node,
+                                          const PrimeMeridianPtr &primeMeridian,
+                                          bool expectEllipsoid);
+
+    MeridianNNPtr buildMeridian(const WKTNodeNNPtr &node);
+    CoordinateSystemAxisNNPtr buildAxis(const WKTNodeNNPtr &node,
+                                        const UnitOfMeasure &unitIn,
+                                        const UnitOfMeasure::Type &unitType,
+                                        bool isGeocentric,
+                                        int expectedOrderNum);
+
+    CoordinateSystemNNPtr buildCS(const WKTNodeNNPtr &node, /* maybe null */
+                                  const WKTNodeNNPtr &parentNode,
+                                  const UnitOfMeasure &defaultAngularUnit);
+
+    GeodeticCRSNNPtr buildGeodeticCRS(const WKTNodeNNPtr &node);
+
+    CRSNNPtr buildDerivedGeodeticCRS(const WKTNodeNNPtr &node);
+
+    static UnitOfMeasure
+    guessUnitForParameter(const std::string &paramName,
+                          const UnitOfMeasure &defaultLinearUnit,
+                          const UnitOfMeasure &defaultAngularUnit);
+
+    void consumeParameters(const WKTNodeNNPtr &node, bool isAbridged,
+                           std::vector<OperationParameterNNPtr> &parameters,
+                           std::vector<ParameterValueNNPtr> &values,
+                           const UnitOfMeasure &defaultLinearUnit,
+                           const UnitOfMeasure &defaultAngularUnit);
+
+    static void addExtensionProj4ToProp(const WKTNode::Private *nodeP,
+                                        PropertyMap &props);
+
+    ConversionNNPtr buildConversion(const WKTNodeNNPtr &node,
+                                    const UnitOfMeasure &defaultLinearUnit,
+                                    const UnitOfMeasure &defaultAngularUnit);
+
+    static bool hasWebMercPROJ4String(const WKTNodeNNPtr &projCRSNode,
+                                      const WKTNodeNNPtr &projectionNode);
+
+    static std::string projectionGetParameter(const WKTNodeNNPtr &projCRSNode,
+                                              const char *paramName);
+
+    ConversionNNPtr buildProjection(const WKTNodeNNPtr &projCRSNode,
+                                    const WKTNodeNNPtr &projectionNode,
+                                    const UnitOfMeasure &defaultLinearUnit,
+                                    const UnitOfMeasure &defaultAngularUnit);
+
+    ConversionNNPtr
+    buildProjectionStandard(const WKTNodeNNPtr &projCRSNode,
+                            const WKTNodeNNPtr &projectionNode,
+                            const UnitOfMeasure &defaultLinearUnit,
+                            const UnitOfMeasure &defaultAngularUnit);
+
+    ConversionNNPtr
+    buildProjectionFromESRI(const WKTNodeNNPtr &projCRSNode,
+                            const WKTNodeNNPtr &projectionNode,
+                            const UnitOfMeasure &defaultLinearUnit,
+                            const UnitOfMeasure &defaultAngularUnit);
+
+    ProjectedCRSNNPtr buildProjectedCRS(const WKTNodeNNPtr &node);
+
+    VerticalReferenceFrameNNPtr
+    buildVerticalReferenceFrame(const WKTNodeNNPtr &node,
+                                const WKTNodeNNPtr &dynamicNode);
+
+    TemporalDatumNNPtr buildTemporalDatum(const WKTNodeNNPtr &node);
+
+    EngineeringDatumNNPtr buildEngineeringDatum(const WKTNodeNNPtr &node);
+
+    ParametricDatumNNPtr buildParametricDatum(const WKTNodeNNPtr &node);
+
+    CRSNNPtr buildVerticalCRS(const WKTNodeNNPtr &node);
+
+    DerivedVerticalCRSNNPtr buildDerivedVerticalCRS(const WKTNodeNNPtr &node);
+
+    CompoundCRSNNPtr buildCompoundCRS(const WKTNodeNNPtr &node);
+
+    BoundCRSNNPtr buildBoundCRS(const WKTNodeNNPtr &node);
+
+    TemporalCSNNPtr buildTemporalCS(const WKTNodeNNPtr &parentNode);
+
+    TemporalCRSNNPtr buildTemporalCRS(const WKTNodeNNPtr &node);
+
+    DerivedTemporalCRSNNPtr buildDerivedTemporalCRS(const WKTNodeNNPtr &node);
+
+    EngineeringCRSNNPtr buildEngineeringCRS(const WKTNodeNNPtr &node);
+
+    EngineeringCRSNNPtr
+    buildEngineeringCRSFromLocalCS(const WKTNodeNNPtr &node);
+
+    DerivedEngineeringCRSNNPtr
+    buildDerivedEngineeringCRS(const WKTNodeNNPtr &node);
+
+    ParametricCSNNPtr buildParametricCS(const WKTNodeNNPtr &parentNode);
+
+    ParametricCRSNNPtr buildParametricCRS(const WKTNodeNNPtr &node);
+
+    DerivedParametricCRSNNPtr
+    buildDerivedParametricCRS(const WKTNodeNNPtr &node);
+
+    DerivedProjectedCRSNNPtr buildDerivedProjectedCRS(const WKTNodeNNPtr &node);
+
+    CRSPtr buildCRS(const WKTNodeNNPtr &node);
+
+    CoordinateOperationNNPtr buildCoordinateOperation(const WKTNodeNNPtr &node);
+
+    ConcatenatedOperationNNPtr
+    buildConcatenatedOperation(const WKTNodeNNPtr &node);
+};
+
+// ---------------------------------------------------------------------------
+
+WKTParser::WKTParser() : d(internal::make_unique<Private>()) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+WKTParser::~WKTParser() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Set whether parsing should be done in strict mode.
+ */
+WKTParser &WKTParser::setStrict(bool strict) {
+    d->strict_ = strict;
+    return *this;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the list of warnings found during parsing.
+ *
+ * \note The list might be non-empty only is setStrict(false) has been called.
+ */
+std::list<std::string> WKTParser::warningList() const {
+    return d->warningList_;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void WKTParser::Private::emitRecoverableAssertion(const std::string &errorMsg) {
+    if (strict_) {
+        throw ParsingException(errorMsg);
+    } else {
+        warningList_.push_back(errorMsg);
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+static double asDouble(const std::string &val) { return c_locale_stod(val); }
+
+// ---------------------------------------------------------------------------
+
+PROJ_NO_RETURN static void ThrowNotEnoughChildren(const std::string &nodeName) {
+    throw ParsingException(
+        concat("not enough children in ", nodeName, " node"));
+}
+
+// ---------------------------------------------------------------------------
+
+PROJ_NO_RETURN static void
+ThrowNotRequiredNumberOfChildren(const std::string &nodeName) {
+    throw ParsingException(
+        concat("not required number of children in ", nodeName, " node"));
+}
+
+// ---------------------------------------------------------------------------
+
+PROJ_NO_RETURN static void ThrowMissing(const std::string &nodeName) {
+    throw ParsingException(concat("missing ", nodeName, " node"));
+}
+
+// ---------------------------------------------------------------------------
+
+PROJ_NO_RETURN static void
+ThrowNotExpectedCSType(const std::string &expectedCSType) {
+    throw ParsingException(concat("CS node is not of type ", expectedCSType));
+}
+
+// ---------------------------------------------------------------------------
+
+static ParsingException buildRethrow(const char *funcName,
+                                     const std::exception &e) {
+    std::string res(funcName);
+    res += ": ";
+    res += e.what();
+    return ParsingException(res);
+}
+
+// ---------------------------------------------------------------------------
+
+std::string WKTParser::Private::stripQuotes(const WKTNodeNNPtr &node) {
+    return ::stripQuotes(node->GP()->value());
+}
+
+// ---------------------------------------------------------------------------
+
+double WKTParser::Private::asDouble(const WKTNodeNNPtr &node) {
+    return io::asDouble(node->GP()->value());
+}
+
+// ---------------------------------------------------------------------------
+
+IdentifierPtr WKTParser::Private::buildId(const WKTNodeNNPtr &node,
+                                          bool tolerant) {
+    const auto *nodeP = node->GP();
+    const auto &nodeChidren = nodeP->children();
+    if (nodeChidren.size() >= 2) {
+        auto codeSpace = stripQuotes(nodeChidren[0]);
+        auto code = stripQuotes(nodeChidren[1]);
+        auto &citationNode = nodeP->lookForChild(WKTConstants::CITATION);
+        auto &uriNode = nodeP->lookForChild(WKTConstants::URI);
+        PropertyMap propertiesId;
+        propertiesId.set(Identifier::CODESPACE_KEY, codeSpace);
+        bool authoritySet = false;
+        /*if (!isNull(citationNode))*/ {
+            const auto *citationNodeP = citationNode->GP();
+            if (citationNodeP->childrenSize() == 1) {
+                authoritySet = true;
+                propertiesId.set(Identifier::AUTHORITY_KEY,
+                                 stripQuotes(citationNodeP->children()[0]));
+            }
+        }
+        if (!authoritySet) {
+            propertiesId.set(Identifier::AUTHORITY_KEY, codeSpace);
+        }
+        /*if (!isNull(uriNode))*/ {
+            const auto *uriNodeP = uriNode->GP();
+            if (uriNodeP->childrenSize() == 1) {
+                propertiesId.set(Identifier::URI_KEY,
+                                 stripQuotes(uriNodeP->children()[0]));
+            }
+        }
+        if (nodeChidren.size() >= 3 &&
+            nodeChidren[2]->GP()->childrenSize() == 0) {
+            auto version = stripQuotes(nodeChidren[2]);
+            propertiesId.set(Identifier::VERSION_KEY, version);
+        }
+        return Identifier::create(code, propertiesId);
+    } else if (strict_ || !tolerant) {
+        ThrowNotEnoughChildren(nodeP->value());
+    } else {
+        std::string msg("not enough children in ");
+        msg += nodeP->value();
+        msg += " node";
+        warningList_.emplace_back(std::move(msg));
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+PropertyMap &WKTParser::Private::buildProperties(const WKTNodeNNPtr &node) {
+
+    if (propertyCount_ == MAX_PROPERTY_SIZE) {
+        throw ParsingException("MAX_PROPERTY_SIZE reached");
+    }
+    properties_[propertyCount_] = new PropertyMap();
+    auto &&properties = properties_[propertyCount_];
+    propertyCount_++;
+
+    std::string authNameFromAlias;
+    std::string codeFromAlias;
+    const auto *nodeP = node->GP();
+    const auto &nodeChildren = nodeP->children();
+    if (!nodeChildren.empty()) {
+        const auto &nodeName(nodeP->value());
+        auto name(stripQuotes(nodeChildren[0]));
+        if (ends_with(name, " (deprecated)")) {
+            name.resize(name.size() - strlen(" (deprecated)"));
+            properties->set(common::IdentifiedObject::DEPRECATED_KEY, true);
+        }
+
+        const char *tableNameForAlias = nullptr;
+        if (ci_equal(nodeName, WKTConstants::GEOGCS)) {
+            if (starts_with(name, "GCS_")) {
+                esriStyle_ = true;
+                if (name == "GCS_WGS_1984") {
+                    name = "WGS 84";
+                } else {
+                    tableNameForAlias = "geodetic_crs";
+                }
+            }
+        } else if (esriStyle_ && ci_equal(nodeName, WKTConstants::SPHEROID)) {
+            if (name == "WGS_1984") {
+                name = "WGS 84";
+                authNameFromAlias = Identifier::EPSG;
+                codeFromAlias = "7030";
+            } else {
+                tableNameForAlias = "ellipsoid";
+            }
+        }
+
+        if (dbContext_ && tableNameForAlias) {
+            std::string outTableName;
+            auto authFactory = AuthorityFactory::create(NN_NO_CHECK(dbContext_),
+                                                        std::string());
+            auto officialName = authFactory->getOfficialNameFromAlias(
+                name, tableNameForAlias, "ESRI", false, outTableName,
+                authNameFromAlias, codeFromAlias);
+            if (!officialName.empty()) {
+                name = officialName;
+
+                // Clearing authority for geodetic_crs because of
+                // potential axis order mismatch.
+                if (strcmp(tableNameForAlias, "geodetic_crs") == 0) {
+                    authNameFromAlias.clear();
+                    codeFromAlias.clear();
+                }
+            }
+        }
+
+        properties->set(IdentifiedObject::NAME_KEY, name);
+    }
+
+    auto identifiers = ArrayOfBaseObject::create();
+    for (const auto &subNode : nodeChildren) {
+        const auto &subNodeName(subNode->GP()->value());
+        if (ci_equal(subNodeName, WKTConstants::ID) ||
+            ci_equal(subNodeName, WKTConstants::AUTHORITY)) {
+            auto id = buildId(subNode);
+            if (id) {
+                identifiers->add(NN_NO_CHECK(id));
+            }
+        }
+    }
+    if (identifiers->empty() && !authNameFromAlias.empty()) {
+        identifiers->add(Identifier::create(
+            codeFromAlias,
+            PropertyMap()
+                .set(Identifier::CODESPACE_KEY, authNameFromAlias)
+                .set(Identifier::AUTHORITY_KEY, authNameFromAlias)));
+    }
+    if (!identifiers->empty()) {
+        properties->set(IdentifiedObject::IDENTIFIERS_KEY, identifiers);
+    }
+
+    auto &remarkNode = nodeP->lookForChild(WKTConstants::REMARK);
+    if (!isNull(remarkNode)) {
+        const auto &remarkChildren = remarkNode->GP()->children();
+        if (remarkChildren.size() == 1) {
+            properties->set(IdentifiedObject::REMARKS_KEY,
+                            stripQuotes(remarkChildren[0]));
+        } else {
+            ThrowNotRequiredNumberOfChildren(remarkNode->GP()->value());
+        }
+    }
+
+    ArrayOfBaseObjectNNPtr array = ArrayOfBaseObject::create();
+    for (const auto &subNode : nodeP->children()) {
+        const auto &subNodeName(subNode->GP()->value());
+        if (ci_equal(subNodeName, WKTConstants::USAGE)) {
+            auto objectDomain = buildObjectDomain(subNode);
+            if (!objectDomain) {
+                throw ParsingException(
+                    concat("missing children in ", subNodeName, " node"));
+            }
+            array->add(NN_NO_CHECK(objectDomain));
+        }
+    }
+    if (!array->empty()) {
+        properties->set(ObjectUsage::OBJECT_DOMAIN_KEY, array);
+    } else {
+        auto objectDomain = buildObjectDomain(node);
+        if (objectDomain) {
+            properties->set(ObjectUsage::OBJECT_DOMAIN_KEY,
+                            NN_NO_CHECK(objectDomain));
+        }
+    }
+
+    return *properties;
+}
+
+// ---------------------------------------------------------------------------
+
+ObjectDomainPtr
+WKTParser::Private::buildObjectDomain(const WKTNodeNNPtr &node) {
+
+    const auto *nodeP = node->GP();
+    auto &scopeNode = nodeP->lookForChild(WKTConstants::SCOPE);
+    auto &areaNode = nodeP->lookForChild(WKTConstants::AREA);
+    auto &bboxNode = nodeP->lookForChild(WKTConstants::BBOX);
+    auto &verticalExtentNode =
+        nodeP->lookForChild(WKTConstants::VERTICALEXTENT);
+    auto &temporalExtentNode = nodeP->lookForChild(WKTConstants::TIMEEXTENT);
+    if (!isNull(scopeNode) || !isNull(areaNode) || !isNull(bboxNode) ||
+        !isNull(verticalExtentNode) || !isNull(temporalExtentNode)) {
+        optional<std::string> scope;
+        const auto *scopeNodeP = scopeNode->GP();
+        const auto &scopeChildren = scopeNodeP->children();
+        if (scopeChildren.size() == 1) {
+            scope = stripQuotes(scopeChildren[0]);
+        }
+        ExtentPtr extent;
+        if (!isNull(areaNode) || !isNull(bboxNode)) {
+            util::optional<std::string> description;
+            std::vector<GeographicExtentNNPtr> geogExtent;
+            std::vector<VerticalExtentNNPtr> verticalExtent;
+            std::vector<TemporalExtentNNPtr> temporalExtent;
+            if (!isNull(areaNode)) {
+                const auto &areaChildren = areaNode->GP()->children();
+                if (areaChildren.size() == 1) {
+                    description = stripQuotes(areaChildren[0]);
+                } else {
+                    ThrowNotRequiredNumberOfChildren(areaNode->GP()->value());
+                }
+            }
+            if (!isNull(bboxNode)) {
+                const auto &bboxChildren = bboxNode->GP()->children();
+                if (bboxChildren.size() == 4) {
+                    try {
+                        double south = asDouble(bboxChildren[0]);
+                        double west = asDouble(bboxChildren[1]);
+                        double north = asDouble(bboxChildren[2]);
+                        double east = asDouble(bboxChildren[3]);
+                        auto bbox = GeographicBoundingBox::create(west, south,
+                                                                  east, north);
+                        geogExtent.emplace_back(bbox);
+                    } catch (const std::exception &) {
+                        throw ParsingException(concat("not 4 double values in ",
+                                                      bboxNode->GP()->value(),
+                                                      " node"));
+                    }
+                } else {
+                    ThrowNotRequiredNumberOfChildren(bboxNode->GP()->value());
+                }
+            }
+
+            if (!isNull(verticalExtentNode)) {
+                const auto &verticalExtentChildren =
+                    verticalExtentNode->GP()->children();
+                const auto verticalExtentChildrenSize =
+                    verticalExtentChildren.size();
+                if (verticalExtentChildrenSize == 2 ||
+                    verticalExtentChildrenSize == 3) {
+                    double min;
+                    double max;
+                    try {
+                        min = asDouble(verticalExtentChildren[0]);
+                        max = asDouble(verticalExtentChildren[1]);
+                    } catch (const std::exception &) {
+                        throw ParsingException(
+                            concat("not 2 double values in ",
+                                   verticalExtentNode->GP()->value(), " node"));
+                    }
+                    UnitOfMeasure unit = UnitOfMeasure::METRE;
+                    if (verticalExtentChildrenSize == 3) {
+                        unit = buildUnit(verticalExtentChildren[2],
+                                         UnitOfMeasure::Type::LINEAR);
+                    }
+                    verticalExtent.emplace_back(VerticalExtent::create(
+                        min, max, util::nn_make_shared<UnitOfMeasure>(unit)));
+                } else {
+                    ThrowNotRequiredNumberOfChildren(
+                        verticalExtentNode->GP()->value());
+                }
+            }
+
+            if (!isNull(temporalExtentNode)) {
+                const auto &temporalExtentChildren =
+                    temporalExtentNode->GP()->children();
+                if (temporalExtentChildren.size() == 2) {
+                    temporalExtent.emplace_back(TemporalExtent::create(
+                        stripQuotes(temporalExtentChildren[0]),
+                        stripQuotes(temporalExtentChildren[1])));
+                } else {
+                    ThrowNotRequiredNumberOfChildren(
+                        temporalExtentNode->GP()->value());
+                }
+            }
+            extent = Extent::create(description, geogExtent, verticalExtent,
+                                    temporalExtent)
+                         .as_nullable();
+        }
+        return ObjectDomain::create(scope, extent).as_nullable();
+    }
+
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+UnitOfMeasure WKTParser::Private::buildUnit(const WKTNodeNNPtr &node,
+                                            UnitOfMeasure::Type type) {
+    const auto *nodeP = node->GP();
+    const auto &children = nodeP->children();
+    if ((type != UnitOfMeasure::Type::TIME && children.size() < 2) ||
+        (type == UnitOfMeasure::Type::TIME && children.size() < 1)) {
+        ThrowNotEnoughChildren(nodeP->value());
+    }
+    try {
+        std::string unitName(stripQuotes(children[0]));
+        PropertyMap properties(buildProperties(node));
+        auto &idNode =
+            nodeP->lookForChild(WKTConstants::ID, WKTConstants::AUTHORITY);
+        if (!isNull(idNode) && idNode->GP()->childrenSize() < 2) {
+            emitRecoverableAssertion("not enough children in " +
+                                     idNode->GP()->value() + " node");
+        }
+        const bool hasValidIdNode =
+            !isNull(idNode) && idNode->GP()->childrenSize() >= 2;
+
+        const auto &idNodeChildren(idNode->GP()->children());
+        std::string codeSpace(hasValidIdNode ? stripQuotes(idNodeChildren[0])
+                                             : std::string());
+        std::string code(hasValidIdNode ? stripQuotes(idNodeChildren[1])
+                                        : std::string());
+
+        bool queryDb = true;
+        if (type == UnitOfMeasure::Type::UNKNOWN) {
+            if (ci_equal(unitName, "METER") || ci_equal(unitName, "METRE")) {
+                type = UnitOfMeasure::Type::LINEAR;
+                unitName = "metre";
+                if (codeSpace.empty()) {
+                    codeSpace = Identifier::EPSG;
+                    code = "9001";
+                    queryDb = false;
+                }
+            } else if (ci_equal(unitName, "DEGREE") ||
+                       ci_equal(unitName, "GRAD")) {
+                type = UnitOfMeasure::Type::ANGULAR;
+            }
+        }
+
+        if (esriStyle_ && dbContext_ && queryDb) {
+            std::string outTableName;
+            std::string authNameFromAlias;
+            std::string codeFromAlias;
+            auto authFactory = AuthorityFactory::create(NN_NO_CHECK(dbContext_),
+                                                        std::string());
+            auto officialName = authFactory->getOfficialNameFromAlias(
+                unitName, "unit_of_measure", "ESRI", false, outTableName,
+                authNameFromAlias, codeFromAlias);
+            if (!officialName.empty()) {
+                unitName = officialName;
+                codeSpace = authNameFromAlias;
+                code = codeFromAlias;
+            }
+        }
+
+        double convFactor = children.size() >= 2 ? asDouble(children[1]) : 0.0;
+        constexpr double US_FOOT_CONV_FACTOR = 12.0 / 39.37;
+        constexpr double REL_ERROR = 1e-10;
+        // Fix common rounding errors
+        if (std::fabs(convFactor - UnitOfMeasure::DEGREE.conversionToSI()) <
+            REL_ERROR * convFactor) {
+            convFactor = UnitOfMeasure::DEGREE.conversionToSI();
+        } else if (std::fabs(convFactor - US_FOOT_CONV_FACTOR) <
+                   REL_ERROR * convFactor) {
+            convFactor = US_FOOT_CONV_FACTOR;
+        }
+
+        return UnitOfMeasure(unitName, convFactor, type, codeSpace, code);
+    } catch (const std::exception &e) {
+        throw buildRethrow(__FUNCTION__, e);
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+// node here is a parent node, not a UNIT/LENGTHUNIT/ANGLEUNIT/TIMEUNIT/... node
+UnitOfMeasure WKTParser::Private::buildUnitInSubNode(const WKTNodeNNPtr &node,
+                                                     UnitOfMeasure::Type type) {
+    const auto *nodeP = node->GP();
+    {
+        auto &unitNode = nodeP->lookForChild(WKTConstants::LENGTHUNIT);
+        if (!isNull(unitNode)) {
+            return buildUnit(unitNode, UnitOfMeasure::Type::LINEAR);
+        }
+    }
+
+    {
+        auto &unitNode = nodeP->lookForChild(WKTConstants::ANGLEUNIT);
+        if (!isNull(unitNode)) {
+            return buildUnit(unitNode, UnitOfMeasure::Type::ANGULAR);
+        }
+    }
+
+    {
+        auto &unitNode = nodeP->lookForChild(WKTConstants::SCALEUNIT);
+        if (!isNull(unitNode)) {
+            return buildUnit(unitNode, UnitOfMeasure::Type::SCALE);
+        }
+    }
+
+    {
+        auto &unitNode = nodeP->lookForChild(WKTConstants::TIMEUNIT);
+        if (!isNull(unitNode)) {
+            return buildUnit(unitNode, UnitOfMeasure::Type::TIME);
+        }
+    }
+    {
+        auto &unitNode = nodeP->lookForChild(WKTConstants::TEMPORALQUANTITY);
+        if (!isNull(unitNode)) {
+            return buildUnit(unitNode, UnitOfMeasure::Type::TIME);
+        }
+    }
+
+    {
+        auto &unitNode = nodeP->lookForChild(WKTConstants::PARAMETRICUNIT);
+        if (!isNull(unitNode)) {
+            return buildUnit(unitNode, UnitOfMeasure::Type::PARAMETRIC);
+        }
+    }
+
+    {
+        auto &unitNode = nodeP->lookForChild(WKTConstants::UNIT);
+        if (!isNull(unitNode)) {
+            return buildUnit(unitNode, type);
+        }
+    }
+
+    return UnitOfMeasure::NONE;
+}
+
+// ---------------------------------------------------------------------------
+
+EllipsoidNNPtr WKTParser::Private::buildEllipsoid(const WKTNodeNNPtr &node) {
+    const auto *nodeP = node->GP();
+    const auto &children = nodeP->children();
+    if (children.size() < 3) {
+        ThrowNotEnoughChildren(nodeP->value());
+    }
+    try {
+        UnitOfMeasure unit =
+            buildUnitInSubNode(node, UnitOfMeasure::Type::LINEAR);
+        if (unit == UnitOfMeasure::NONE) {
+            unit = UnitOfMeasure::METRE;
+        }
+        Length semiMajorAxis(asDouble(children[1]), unit);
+        Scale invFlattening(asDouble(children[2]));
+        const auto celestialBody(
+            Ellipsoid::guessBodyName(dbContext_, semiMajorAxis.getSIValue()));
+        if (invFlattening.getSIValue() == 0) {
+            return Ellipsoid::createSphere(buildProperties(node), semiMajorAxis,
+                                           celestialBody);
+        } else {
+            return Ellipsoid::createFlattenedSphere(
+                buildProperties(node), semiMajorAxis, invFlattening,
+                celestialBody);
+        }
+    } catch (const std::exception &e) {
+        throw buildRethrow(__FUNCTION__, e);
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+PrimeMeridianNNPtr WKTParser::Private::buildPrimeMeridian(
+    const WKTNodeNNPtr &node, const UnitOfMeasure &defaultAngularUnit) {
+    const auto *nodeP = node->GP();
+    const auto &children = nodeP->children();
+    if (children.size() < 2) {
+        ThrowNotEnoughChildren(nodeP->value());
+    }
+    auto name = stripQuotes(children[0]);
+    UnitOfMeasure unit = buildUnitInSubNode(node, UnitOfMeasure::Type::ANGULAR);
+    if (unit == UnitOfMeasure::NONE) {
+        unit = defaultAngularUnit;
+        if (unit == UnitOfMeasure::NONE) {
+            unit = UnitOfMeasure::DEGREE;
+        }
+    }
+    try {
+        double angleValue = asDouble(children[1]);
+
+        // Correct for GDAL WKT1 departure
+        if (name == "Paris" && std::fabs(angleValue - 2.33722917) < 1e-8 &&
+            unit == UnitOfMeasure::GRAD) {
+            angleValue = 2.5969213;
+        }
+
+        Angle angle(angleValue, unit);
+        return PrimeMeridian::create(buildProperties(node), angle);
+    } catch (const std::exception &e) {
+        throw buildRethrow(__FUNCTION__, e);
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+optional<std::string> WKTParser::Private::getAnchor(const WKTNodeNNPtr &node) {
+
+    auto &anchorNode = node->GP()->lookForChild(WKTConstants::ANCHOR);
+    if (anchorNode->GP()->childrenSize() == 1) {
+        return optional<std::string>(
+            stripQuotes(anchorNode->GP()->children()[0]));
+    }
+    return optional<std::string>();
+}
+
+// ---------------------------------------------------------------------------
+
+static const PrimeMeridianNNPtr &
+fixupPrimeMeridan(const EllipsoidNNPtr &ellipsoid,
+                  const PrimeMeridianNNPtr &pm) {
+    return (ellipsoid->celestialBody() != Ellipsoid::EARTH &&
+            pm.get() == PrimeMeridian::GREENWICH.get())
+               ? PrimeMeridian::REFERENCE_MERIDIAN
+               : pm;
+}
+
+// ---------------------------------------------------------------------------
+
+GeodeticReferenceFrameNNPtr WKTParser::Private::buildGeodeticReferenceFrame(
+    const WKTNodeNNPtr &node, const PrimeMeridianNNPtr &primeMeridian,
+    const WKTNodeNNPtr &dynamicNode) {
+    const auto *nodeP = node->GP();
+    auto &ellipsoidNode =
+        nodeP->lookForChild(WKTConstants::ELLIPSOID, WKTConstants::SPHEROID);
+    if (isNull(ellipsoidNode)) {
+        ThrowMissing(WKTConstants::ELLIPSOID);
+    }
+    auto &properties = buildProperties(node);
+
+    // do that before buildEllipsoid() so that esriStyle_ can be set
+    auto name = stripQuotes(nodeP->children()[0]);
+    if (name == "WGS_1984") {
+        properties.set(IdentifiedObject::NAME_KEY,
+                       GeodeticReferenceFrame::EPSG_6326->nameStr());
+    } else if (starts_with(name, "D_")) {
+        esriStyle_ = true;
+        const char *tableNameForAlias = nullptr;
+        std::string authNameFromAlias;
+        std::string codeFromAlias;
+        if (name == "D_WGS_1984") {
+            name = "World Geodetic System 1984";
+            authNameFromAlias = Identifier::EPSG;
+            codeFromAlias = "6326";
+        } else {
+            tableNameForAlias = "geodetic_datum";
+        }
+
+        if (dbContext_ && tableNameForAlias) {
+            std::string outTableName;
+            auto authFactory = AuthorityFactory::create(NN_NO_CHECK(dbContext_),
+                                                        std::string());
+            auto officialName = authFactory->getOfficialNameFromAlias(
+                name, tableNameForAlias, "ESRI", false, outTableName,
+                authNameFromAlias, codeFromAlias);
+            if (!officialName.empty()) {
+                if (primeMeridian->nameStr() !=
+                    PrimeMeridian::GREENWICH->nameStr()) {
+                    auto nameWithPM =
+                        officialName + " (" + primeMeridian->nameStr() + ")";
+                    if (dbContext_->isKnownName(nameWithPM, "geodetic_datum")) {
+                        officialName = nameWithPM;
+                    }
+                }
+                name = officialName;
+            }
+        }
+
+        properties.set(IdentifiedObject::NAME_KEY, name);
+        if (!authNameFromAlias.empty()) {
+            auto identifiers = ArrayOfBaseObject::create();
+            identifiers->add(Identifier::create(
+                codeFromAlias,
+                PropertyMap()
+                    .set(Identifier::CODESPACE_KEY, authNameFromAlias)
+                    .set(Identifier::AUTHORITY_KEY, authNameFromAlias)));
+            properties.set(IdentifiedObject::IDENTIFIERS_KEY, identifiers);
+        }
+    } else if (name.find('_') != std::string::npos) {
+        // Likely coming from WKT1
+        if (dbContext_) {
+            auto authFactory = AuthorityFactory::create(NN_NO_CHECK(dbContext_),
+                                                        std::string());
+            auto res = authFactory->createObjectsFromName(
+                name, {AuthorityFactory::ObjectType::GEODETIC_REFERENCE_FRAME},
+                true, 1);
+            bool foundDatumName = false;
+            if (!res.empty()) {
+                const auto &refDatum = res.front();
+                if (metadata::Identifier::isEquivalentName(
+                        name.c_str(), refDatum->nameStr().c_str())) {
+                    foundDatumName = true;
+                    properties.set(IdentifiedObject::NAME_KEY,
+                                   refDatum->nameStr());
+                    if (!properties.get(Identifier::CODESPACE_KEY) &&
+                        refDatum->identifiers().size() == 1) {
+                        const auto &id = refDatum->identifiers()[0];
+                        auto identifiers = ArrayOfBaseObject::create();
+                        identifiers->add(Identifier::create(
+                            id->code(), PropertyMap()
+                                            .set(Identifier::CODESPACE_KEY,
+                                                 *id->codeSpace())
+                                            .set(Identifier::AUTHORITY_KEY,
+                                                 *id->codeSpace())));
+                        properties.set(IdentifiedObject::IDENTIFIERS_KEY,
+                                       identifiers);
+                    }
+                }
+            } else {
+                // Get official name from database if AUTHORITY is present
+                auto &idNode = nodeP->lookForChild(WKTConstants::AUTHORITY);
+                if (!isNull(idNode)) {
+                    try {
+                        auto id = buildId(idNode);
+                        auto authFactory2 = AuthorityFactory::create(
+                            NN_NO_CHECK(dbContext_), *id->codeSpace());
+                        auto dbDatum =
+                            authFactory2->createGeodeticDatum(id->code());
+                        foundDatumName = true;
+                        properties.set(IdentifiedObject::NAME_KEY,
+                                       dbDatum->nameStr());
+                    } catch (const std::exception &) {
+                    }
+                }
+            }
+
+            if (!foundDatumName) {
+                std::string outTableName;
+                std::string authNameFromAlias;
+                std::string codeFromAlias;
+                auto officialName = authFactory->getOfficialNameFromAlias(
+                    name, "geodetic_datum", std::string(), true, outTableName,
+                    authNameFromAlias, codeFromAlias);
+                if (!officialName.empty()) {
+                    properties.set(IdentifiedObject::NAME_KEY, officialName);
+                }
+            }
+        }
+    }
+
+    auto ellipsoid = buildEllipsoid(ellipsoidNode);
+    const auto &primeMeridianModified =
+        fixupPrimeMeridan(ellipsoid, primeMeridian);
+
+    auto &TOWGS84Node = nodeP->lookForChild(WKTConstants::TOWGS84);
+    if (!isNull(TOWGS84Node)) {
+        const auto &TOWGS84Children = TOWGS84Node->GP()->children();
+        const size_t TOWGS84Size = TOWGS84Children.size();
+        if (TOWGS84Size == 3 || TOWGS84Size == 7) {
+            try {
+                for (const auto &child : TOWGS84Children) {
+                    toWGS84Parameters_.push_back(asDouble(child));
+                }
+                for (size_t i = TOWGS84Size; i < 7; ++i) {
+                    toWGS84Parameters_.push_back(0.0);
+                }
+            } catch (const std::exception &) {
+                throw ParsingException("Invalid TOWGS84 node");
+            }
+        } else {
+            throw ParsingException("Invalid TOWGS84 node");
+        }
+    }
+
+    auto &extensionNode = nodeP->lookForChild(WKTConstants::EXTENSION);
+    const auto &extensionChildren = extensionNode->GP()->children();
+    if (extensionChildren.size() == 2) {
+        if (ci_equal(stripQuotes(extensionChildren[0]), "PROJ4_GRIDS")) {
+            datumPROJ4Grids_ = stripQuotes(extensionChildren[1]);
+        }
+    }
+
+    if (!isNull(dynamicNode)) {
+        double frameReferenceEpoch = 0.0;
+        util::optional<std::string> modelName;
+        parseDynamic(dynamicNode, frameReferenceEpoch, modelName);
+        return DynamicGeodeticReferenceFrame::create(
+            properties, ellipsoid, getAnchor(node), primeMeridianModified,
+            common::Measure(frameReferenceEpoch, common::UnitOfMeasure::YEAR),
+            modelName);
+    }
+
+    return GeodeticReferenceFrame::create(
+        properties, ellipsoid, getAnchor(node), primeMeridianModified);
+}
+
+// ---------------------------------------------------------------------------
+
+DatumEnsembleNNPtr
+WKTParser::Private::buildDatumEnsemble(const WKTNodeNNPtr &node,
+                                       const PrimeMeridianPtr &primeMeridian,
+                                       bool expectEllipsoid) {
+    const auto *nodeP = node->GP();
+    auto &ellipsoidNode =
+        nodeP->lookForChild(WKTConstants::ELLIPSOID, WKTConstants::SPHEROID);
+    if (expectEllipsoid && isNull(ellipsoidNode)) {
+        ThrowMissing(WKTConstants::ELLIPSOID);
+    }
+
+    std::vector<DatumNNPtr> datums;
+    for (const auto &subNode : nodeP->children()) {
+        if (ci_equal(subNode->GP()->value(), WKTConstants::MEMBER)) {
+            if (subNode->GP()->childrenSize() == 0) {
+                throw ParsingException("Invalid MEMBER node");
+            }
+            if (expectEllipsoid) {
+                datums.emplace_back(GeodeticReferenceFrame::create(
+                    buildProperties(subNode), buildEllipsoid(ellipsoidNode),
+                    optional<std::string>(),
+                    primeMeridian ? NN_NO_CHECK(primeMeridian)
+                                  : PrimeMeridian::GREENWICH));
+            } else {
+                datums.emplace_back(
+                    VerticalReferenceFrame::create(buildProperties(subNode)));
+            }
+        }
+    }
+
+    auto &accuracyNode = nodeP->lookForChild(WKTConstants::ENSEMBLEACCURACY);
+    auto &accuracyNodeChildren = accuracyNode->GP()->children();
+    if (accuracyNodeChildren.empty()) {
+        ThrowMissing(WKTConstants::ENSEMBLEACCURACY);
+    }
+    auto accuracy =
+        PositionalAccuracy::create(accuracyNodeChildren[0]->GP()->value());
+
+    try {
+        return DatumEnsemble::create(buildProperties(node), datums, accuracy);
+    } catch (const util::Exception &e) {
+        throw buildRethrow(__FUNCTION__, e);
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+MeridianNNPtr WKTParser::Private::buildMeridian(const WKTNodeNNPtr &node) {
+    const auto *nodeP = node->GP();
+    const auto &children = nodeP->children();
+    if (children.size() < 2) {
+        ThrowNotEnoughChildren(nodeP->value());
+    }
+    UnitOfMeasure unit = buildUnitInSubNode(node, UnitOfMeasure::Type::ANGULAR);
+    try {
+        double angleValue = asDouble(children[0]);
+        Angle angle(angleValue, unit);
+        return Meridian::create(angle);
+    } catch (const std::exception &e) {
+        throw buildRethrow(__FUNCTION__, e);
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+PROJ_NO_RETURN static void ThrowParsingExceptionMissingUNIT() {
+    throw ParsingException("buildCS: missing UNIT");
+}
+
+// ---------------------------------------------------------------------------
+
+CoordinateSystemAxisNNPtr
+WKTParser::Private::buildAxis(const WKTNodeNNPtr &node,
+                              const UnitOfMeasure &unitIn,
+                              const UnitOfMeasure::Type &unitType,
+                              bool isGeocentric, int expectedOrderNum) {
+    const auto *nodeP = node->GP();
+    const auto &children = nodeP->children();
+    if (children.size() < 2) {
+        ThrowNotEnoughChildren(nodeP->value());
+    }
+
+    auto &orderNode = nodeP->lookForChild(WKTConstants::ORDER);
+    if (!isNull(orderNode)) {
+        const auto &orderNodeChildren = orderNode->GP()->children();
+        if (orderNodeChildren.size() != 1) {
+            ThrowNotEnoughChildren(WKTConstants::ORDER);
+        }
+        const auto &order = orderNodeChildren[0]->GP()->value();
+        int orderNum;
+        try {
+            orderNum = std::stoi(order);
+        } catch (const std::exception &) {
+            throw ParsingException(
+                concat("buildAxis: invalid ORDER value: ", order));
+        }
+        if (orderNum != expectedOrderNum) {
+            throw ParsingException(
+                concat("buildAxis: did not get expected ORDER value: ", order));
+        }
+    }
+
+    // The axis designation in WK2 can be: "name", "(abbrev)" or "name
+    // (abbrev)"
+    std::string axisDesignation(stripQuotes(children[0]));
+    size_t sepPos = axisDesignation.find(" (");
+    std::string axisName;
+    std::string abbreviation;
+    if (sepPos != std::string::npos && axisDesignation.back() == ')') {
+        axisName = CoordinateSystemAxis::normalizeAxisName(
+            axisDesignation.substr(0, sepPos));
+        abbreviation = axisDesignation.substr(sepPos + 2);
+        abbreviation.resize(abbreviation.size() - 1);
+    } else if (!axisDesignation.empty() && axisDesignation[0] == '(' &&
+               axisDesignation.back() == ')') {
+        abbreviation = axisDesignation.substr(1, axisDesignation.size() - 2);
+        if (abbreviation == AxisAbbreviation::E) {
+            axisName = AxisName::Easting;
+        } else if (abbreviation == AxisAbbreviation::N) {
+            axisName = AxisName::Northing;
+        } else if (abbreviation == AxisAbbreviation::lat) {
+            axisName = AxisName::Latitude;
+        } else if (abbreviation == AxisAbbreviation::lon) {
+            axisName = AxisName::Longitude;
+        }
+    } else {
+        axisName = CoordinateSystemAxis::normalizeAxisName(axisDesignation);
+        if (axisName == AxisName::Latitude) {
+            abbreviation = AxisAbbreviation::lat;
+        } else if (axisName == AxisName::Longitude) {
+            abbreviation = AxisAbbreviation::lon;
+        } else if (axisName == AxisName::Ellipsoidal_height) {
+            abbreviation = AxisAbbreviation::h;
+        }
+    }
+    const std::string &dirString = children[1]->GP()->value();
+    const AxisDirection *direction = AxisDirection::valueOf(dirString);
+
+    // WKT2, geocentric CS: axis names are omitted
+    if (axisName.empty()) {
+        if (direction == &AxisDirection::GEOCENTRIC_X &&
+            abbreviation == AxisAbbreviation::X) {
+            axisName = AxisName::Geocentric_X;
+        } else if (direction == &AxisDirection::GEOCENTRIC_Y &&
+                   abbreviation == AxisAbbreviation::Y) {
+            axisName = AxisName::Geocentric_Y;
+        } else if (direction == &AxisDirection::GEOCENTRIC_Z &&
+                   abbreviation == AxisAbbreviation::Z) {
+            axisName = AxisName::Geocentric_Z;
+        }
+    }
+
+    // WKT1
+    if (!direction && isGeocentric && axisName == AxisName::Geocentric_X) {
+        abbreviation = AxisAbbreviation::X;
+        direction = &AxisDirection::GEOCENTRIC_X;
+    } else if (!direction && isGeocentric &&
+               axisName == AxisName::Geocentric_Y) {
+        abbreviation = AxisAbbreviation::Y;
+        direction = &AxisDirection::GEOCENTRIC_Y;
+    } else if (isGeocentric && axisName == AxisName::Geocentric_Z &&
+               (dirString == AxisDirectionWKT1::NORTH.toString() ||
+                dirString == AxisDirectionWKT1::OTHER.toString())) {
+        abbreviation = AxisAbbreviation::Z;
+        direction = &AxisDirection::GEOCENTRIC_Z;
+    } else if (dirString == AxisDirectionWKT1::OTHER.toString()) {
+        direction = &AxisDirection::UNSPECIFIED;
+    } else if (!direction && AxisDirectionWKT1::valueOf(dirString) != nullptr) {
+        direction = AxisDirection::valueOf(tolower(dirString));
+    }
+
+    if (!direction) {
+        throw ParsingException(
+            concat("unhandled axis direction: ", children[1]->GP()->value()));
+    }
+    UnitOfMeasure unit(buildUnitInSubNode(node));
+    if (unit == UnitOfMeasure::NONE) {
+        // If no unit in the AXIS node, use the one potentially coming from
+        // the CS.
+        unit = unitIn;
+        if (unit == UnitOfMeasure::NONE &&
+            unitType != UnitOfMeasure::Type::NONE &&
+            unitType != UnitOfMeasure::Type::TIME) {
+            ThrowParsingExceptionMissingUNIT();
+        }
+    }
+
+    auto &meridianNode = nodeP->lookForChild(WKTConstants::MERIDIAN);
+
+    return CoordinateSystemAxis::create(
+        buildProperties(node).set(IdentifiedObject::NAME_KEY, axisName),
+        abbreviation, *direction, unit,
+        !isNull(meridianNode) ? buildMeridian(meridianNode).as_nullable()
+                              : nullptr);
+}
+
+// ---------------------------------------------------------------------------
+
+static const PropertyMap emptyPropertyMap{};
+
+PROJ_NO_RETURN static void ThrowParsingException(const std::string &msg) {
+    throw ParsingException(msg);
+}
+
+static ParsingException
+buildParsingExceptionInvalidAxisCount(const std::string &csType) {
+    return ParsingException(
+        concat("buildCS: invalid CS axis count for ", csType));
+}
+
+CoordinateSystemNNPtr
+WKTParser::Private::buildCS(const WKTNodeNNPtr &node, /* maybe null */
+                            const WKTNodeNNPtr &parentNode,
+                            const UnitOfMeasure &defaultAngularUnit) {
+    bool isGeocentric = false;
+    std::string csType;
+    const int numberOfAxis =
+        parentNode->countChildrenOfName(WKTConstants::AXIS);
+    int axisCount = numberOfAxis;
+    if (!isNull(node)) {
+        const auto *nodeP = node->GP();
+        const auto &children = nodeP->children();
+        if (children.size() < 2) {
+            ThrowNotEnoughChildren(nodeP->value());
+        }
+        csType = children[0]->GP()->value();
+        try {
+            axisCount = std::stoi(children[1]->GP()->value());
+        } catch (const std::exception &) {
+            ThrowParsingException(concat("buildCS: invalid CS axis count: ",
+                                         children[1]->GP()->value()));
+        }
+    } else {
+        const char *csTypeCStr = "";
+        const auto &parentNodeName = parentNode->GP()->value();
+        if (ci_equal(parentNodeName, WKTConstants::GEOCCS)) {
+            csTypeCStr = "Cartesian";
+            isGeocentric = true;
+            if (axisCount == 0) {
+                auto unit =
+                    buildUnitInSubNode(parentNode, UnitOfMeasure::Type::LINEAR);
+                if (unit == UnitOfMeasure::NONE) {
+                    ThrowParsingExceptionMissingUNIT();
+                }
+                return CartesianCS::createGeocentric(unit);
+            }
+        } else if (ci_equal(parentNodeName, WKTConstants::GEOGCS)) {
+            csTypeCStr = "Ellipsoidal";
+            if (axisCount == 0) {
+                // Missing axis with GEOGCS ? Presumably Long/Lat order
+                // implied
+                auto unit = buildUnitInSubNode(parentNode,
+                                               UnitOfMeasure::Type::ANGULAR);
+                if (unit == UnitOfMeasure::NONE) {
+                    ThrowParsingExceptionMissingUNIT();
+                }
+                // WKT1 --> long/lat
+                return EllipsoidalCS::createLongitudeLatitude(unit);
+            }
+        } else if (ci_equal(parentNodeName, WKTConstants::BASEGEODCRS) ||
+                   ci_equal(parentNodeName, WKTConstants::BASEGEOGCRS)) {
+            csTypeCStr = "Ellipsoidal";
+            if (axisCount == 0) {
+                auto unit = buildUnitInSubNode(parentNode,
+                                               UnitOfMeasure::Type::ANGULAR);
+                if (unit == UnitOfMeasure::NONE) {
+                    unit = defaultAngularUnit;
+                }
+                // WKT2 --> presumably lat/long
+                return EllipsoidalCS::createLatitudeLongitude(unit);
+            }
+        } else if (ci_equal(parentNodeName, WKTConstants::PROJCS) ||
+                   ci_equal(parentNodeName, WKTConstants::BASEPROJCRS) ||
+                   ci_equal(parentNodeName, WKTConstants::BASEENGCRS)) {
+            csTypeCStr = "Cartesian";
+            if (axisCount == 0) {
+                auto unit =
+                    buildUnitInSubNode(parentNode, UnitOfMeasure::Type::LINEAR);
+                if (unit == UnitOfMeasure::NONE) {
+                    if (ci_equal(parentNodeName, WKTConstants::PROJCS)) {
+                        ThrowParsingExceptionMissingUNIT();
+                    } else {
+                        unit = UnitOfMeasure::METRE;
+                    }
+                }
+                return CartesianCS::createEastingNorthing(unit);
+            }
+        } else if (ci_equal(parentNodeName, WKTConstants::VERT_CS) ||
+                   ci_equal(parentNodeName, WKTConstants::BASEVERTCRS)) {
+            csTypeCStr = "vertical";
+            if (axisCount == 0) {
+                auto unit =
+                    buildUnitInSubNode(parentNode, UnitOfMeasure::Type::LINEAR);
+                if (unit == UnitOfMeasure::NONE) {
+                    if (ci_equal(parentNodeName, WKTConstants::VERT_CS)) {
+                        ThrowParsingExceptionMissingUNIT();
+                    } else {
+                        unit = UnitOfMeasure::METRE;
+                    }
+                }
+                return VerticalCS::createGravityRelatedHeight(unit);
+            }
+        } else if (ci_equal(parentNodeName, WKTConstants::LOCAL_CS)) {
+            if (axisCount == 0) {
+                auto unit =
+                    buildUnitInSubNode(parentNode, UnitOfMeasure::Type::LINEAR);
+                if (unit == UnitOfMeasure::NONE) {
+                    unit = UnitOfMeasure::METRE;
+                }
+                return CartesianCS::createEastingNorthing(unit);
+            } else if (axisCount == 1) {
+                csTypeCStr = "vertical";
+            } else if (axisCount == 2) {
+                csTypeCStr = "Cartesian";
+            } else {
+                throw ParsingException(
+                    "buildCS: unexpected AXIS count for LOCAL_CS");
+            }
+        } else if (ci_equal(parentNodeName, WKTConstants::BASEPARAMCRS)) {
+            csTypeCStr = "parametric";
+            if (axisCount == 0) {
+                auto unit =
+                    buildUnitInSubNode(parentNode, UnitOfMeasure::Type::LINEAR);
+                if (unit == UnitOfMeasure::NONE) {
+                    unit = UnitOfMeasure("unknown", 1,
+                                         UnitOfMeasure::Type::PARAMETRIC);
+                }
+                return ParametricCS::create(
+                    emptyPropertyMap,
+                    CoordinateSystemAxis::create(
+                        PropertyMap().set(IdentifiedObject::NAME_KEY,
+                                          "unknown parametric"),
+                        std::string(), AxisDirection::UNSPECIFIED, unit));
+            }
+        } else if (ci_equal(parentNodeName, WKTConstants::BASETIMECRS)) {
+            csTypeCStr = "temporal";
+            if (axisCount == 0) {
+                auto unit =
+                    buildUnitInSubNode(parentNode, UnitOfMeasure::Type::TIME);
+                if (unit == UnitOfMeasure::NONE) {
+                    unit =
+                        UnitOfMeasure("unknown", 1, UnitOfMeasure::Type::TIME);
+                }
+                return DateTimeTemporalCS::create(
+                    emptyPropertyMap,
+                    CoordinateSystemAxis::create(
+                        PropertyMap().set(IdentifiedObject::NAME_KEY,
+                                          "unknown temporal"),
+                        std::string(), AxisDirection::FUTURE, unit));
+            }
+        } else {
+            // Shouldn't happen normally
+            throw ParsingException(
+                concat("buildCS: unexpected parent node: ", parentNodeName));
+        }
+        csType = csTypeCStr;
+    }
+
+    if (axisCount != 1 && axisCount != 2 && axisCount != 3) {
+        throw buildParsingExceptionInvalidAxisCount(csType);
+    }
+    if (numberOfAxis != axisCount) {
+        throw ParsingException("buildCS: declared number of axis by CS node "
+                               "and number of AXIS are inconsistent");
+    }
+
+    const auto unitType =
+        ci_equal(csType, "ellipsoidal")
+            ? UnitOfMeasure::Type::ANGULAR
+            : ci_equal(csType, "ordinal")
+                  ? UnitOfMeasure::Type::NONE
+                  : ci_equal(csType, "parametric")
+                        ? UnitOfMeasure::Type::PARAMETRIC
+                        : ci_equal(csType, "Cartesian") ||
+                                  ci_equal(csType, "vertical")
+                              ? UnitOfMeasure::Type::LINEAR
+                              : (ci_equal(csType, "temporal") ||
+                                 ci_equal(csType, "TemporalDateTime") ||
+                                 ci_equal(csType, "TemporalCount") ||
+                                 ci_equal(csType, "TemporalMeasure"))
+                                    ? UnitOfMeasure::Type::TIME
+                                    : UnitOfMeasure::Type::UNKNOWN;
+    UnitOfMeasure unit = buildUnitInSubNode(parentNode, unitType);
+
+    std::vector<CoordinateSystemAxisNNPtr> axisList;
+    for (int i = 0; i < axisCount; i++) {
+        axisList.emplace_back(
+            buildAxis(parentNode->GP()->lookForChild(WKTConstants::AXIS, i),
+                      unit, unitType, isGeocentric, i + 1));
+    };
+
+    const PropertyMap &csMap = emptyPropertyMap;
+    if (ci_equal(csType, "ellipsoidal")) {
+        if (axisCount == 2) {
+            return EllipsoidalCS::create(csMap, axisList[0], axisList[1]);
+        } else if (axisCount == 3) {
+            return EllipsoidalCS::create(csMap, axisList[0], axisList[1],
+                                         axisList[2]);
+        }
+    } else if (ci_equal(csType, "Cartesian")) {
+        if (axisCount == 2) {
+            return CartesianCS::create(csMap, axisList[0], axisList[1]);
+        } else if (axisCount == 3) {
+            return CartesianCS::create(csMap, axisList[0], axisList[1],
+                                       axisList[2]);
+        }
+    } else if (ci_equal(csType, "vertical")) {
+        if (axisCount == 1) {
+            return VerticalCS::create(csMap, axisList[0]);
+        }
+    } else if (ci_equal(csType, "spherical")) {
+        if (axisCount == 3) {
+            return SphericalCS::create(csMap, axisList[0], axisList[1],
+                                       axisList[2]);
+        }
+    } else if (ci_equal(csType, "ordinal")) { // WKT2-2018
+        return OrdinalCS::create(csMap, axisList);
+    } else if (ci_equal(csType, "parametric")) {
+        if (axisCount == 1) {
+            return ParametricCS::create(csMap, axisList[0]);
+        }
+    } else if (ci_equal(csType, "temporal")) { // WKT2-2015
+        if (axisCount == 1) {
+            return DateTimeTemporalCS::create(
+                csMap,
+                axisList[0]); // FIXME: there are 3 possible subtypes of
+                              // TemporalCS
+        }
+    } else if (ci_equal(csType, "TemporalDateTime")) { // WKT2-2018
+        if (axisCount == 1) {
+            return DateTimeTemporalCS::create(csMap, axisList[0]);
+        }
+    } else if (ci_equal(csType, "TemporalCount")) { // WKT2-2018
+        if (axisCount == 1) {
+            return TemporalCountCS::create(csMap, axisList[0]);
+        }
+    } else if (ci_equal(csType, "TemporalMeasure")) { // WKT2-2018
+        if (axisCount == 1) {
+            return TemporalMeasureCS::create(csMap, axisList[0]);
+        }
+    } else {
+        throw ParsingException(concat("unhandled CS type: ", csType));
+    }
+    throw buildParsingExceptionInvalidAxisCount(csType);
+}
+
+// ---------------------------------------------------------------------------
+
+void WKTParser::Private::addExtensionProj4ToProp(const WKTNode::Private *nodeP,
+                                                 PropertyMap &props) {
+    auto &extensionNode = nodeP->lookForChild(WKTConstants::EXTENSION);
+    const auto &extensionChildren = extensionNode->GP()->children();
+    if (extensionChildren.size() == 2) {
+        if (ci_equal(stripQuotes(extensionChildren[0]), "PROJ4")) {
+            props.set("EXTENSION_PROJ4", stripQuotes(extensionChildren[1]));
+        }
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+GeodeticCRSNNPtr
+WKTParser::Private::buildGeodeticCRS(const WKTNodeNNPtr &node) {
+    const auto *nodeP = node->GP();
+    auto &datumNode = nodeP->lookForChild(
+        WKTConstants::DATUM, WKTConstants::GEODETICDATUM, WKTConstants::TRF);
+    auto &ensembleNode = nodeP->lookForChild(WKTConstants::ENSEMBLE);
+    if (isNull(datumNode) && isNull(ensembleNode)) {
+        throw ParsingException("Missing DATUM or ENSEMBLE node");
+    }
+
+    auto &dynamicNode = nodeP->lookForChild(WKTConstants::DYNAMIC);
+
+    auto &csNode = nodeP->lookForChild(WKTConstants::CS);
+    const auto &nodeName = nodeP->value();
+    if (isNull(csNode) && !ci_equal(nodeName, WKTConstants::GEOGCS) &&
+        !ci_equal(nodeName, WKTConstants::GEOCCS) &&
+        !ci_equal(nodeName, WKTConstants::BASEGEODCRS) &&
+        !ci_equal(nodeName, WKTConstants::BASEGEOGCRS)) {
+        ThrowMissing(WKTConstants::CS);
+    }
+
+    auto &primeMeridianNode =
+        nodeP->lookForChild(WKTConstants::PRIMEM, WKTConstants::PRIMEMERIDIAN);
+    if (isNull(primeMeridianNode)) {
+        // PRIMEM is required in WKT1
+        if (ci_equal(nodeName, WKTConstants::GEOGCS) ||
+            ci_equal(nodeName, WKTConstants::GEOCCS)) {
+            emitRecoverableAssertion(nodeName + " should have a PRIMEM node");
+        }
+    }
+
+    auto angularUnit =
+        buildUnitInSubNode(node, ci_equal(nodeName, WKTConstants::GEOGCS)
+                                     ? UnitOfMeasure::Type::ANGULAR
+                                     : UnitOfMeasure::Type::UNKNOWN);
+    if (angularUnit.type() != UnitOfMeasure::Type::ANGULAR) {
+        angularUnit = UnitOfMeasure::NONE;
+    }
+
+    auto primeMeridian =
+        !isNull(primeMeridianNode)
+            ? buildPrimeMeridian(primeMeridianNode, angularUnit)
+            : PrimeMeridian::GREENWICH;
+    if (angularUnit == UnitOfMeasure::NONE) {
+        angularUnit = primeMeridian->longitude().unit();
+    }
+
+    auto props = buildProperties(node);
+    addExtensionProj4ToProp(nodeP, props);
+
+    // No explicit AXIS node ? (WKT1)
+    if (isNull(nodeP->lookForChild(WKTConstants::AXIS))) {
+        props.set("IMPLICIT_CS", true);
+    }
+
+    auto datum =
+        !isNull(datumNode)
+            ? buildGeodeticReferenceFrame(datumNode, primeMeridian, dynamicNode)
+                  .as_nullable()
+            : nullptr;
+    auto datumEnsemble =
+        !isNull(ensembleNode)
+            ? buildDatumEnsemble(ensembleNode, primeMeridian, true)
+                  .as_nullable()
+            : nullptr;
+    auto cs = buildCS(csNode, node, angularUnit);
+    auto ellipsoidalCS = nn_dynamic_pointer_cast<EllipsoidalCS>(cs);
+    if (ellipsoidalCS) {
+        assert(!ci_equal(nodeName, WKTConstants::GEOCCS));
+        try {
+            return GeographicCRS::create(props, datum, datumEnsemble,
+                                         NN_NO_CHECK(ellipsoidalCS));
+        } catch (const util::Exception &e) {
+            throw ParsingException(std::string("buildGeodeticCRS: ") +
+                                   e.what());
+        }
+    } else if (ci_equal(nodeName, WKTConstants::GEOGCRS) ||
+               ci_equal(nodeName, WKTConstants::GEOGRAPHICCRS) ||
+               ci_equal(nodeName, WKTConstants::BASEGEOGCRS)) {
+        // This is a WKT2-2018 GeographicCRS. An ellipsoidal CS is expected
+        throw ParsingException(concat("ellipsoidal CS expected, but found ",
+                                      cs->getWKT2Type(true)));
+    }
+
+    auto cartesianCS = nn_dynamic_pointer_cast<CartesianCS>(cs);
+    if (cartesianCS) {
+        if (cartesianCS->axisList().size() != 3) {
+            throw ParsingException(
+                "Cartesian CS for a GeodeticCRS should have 3 axis");
+        }
+        try {
+            return GeodeticCRS::create(props, datum, datumEnsemble,
+                                       NN_NO_CHECK(cartesianCS));
+        } catch (const util::Exception &e) {
+            throw ParsingException(std::string("buildGeodeticCRS: ") +
+                                   e.what());
+        }
+    }
+
+    auto sphericalCS = nn_dynamic_pointer_cast<SphericalCS>(cs);
+    if (sphericalCS) {
+        try {
+            return GeodeticCRS::create(props, datum, datumEnsemble,
+                                       NN_NO_CHECK(sphericalCS));
+        } catch (const util::Exception &e) {
+            throw ParsingException(std::string("buildGeodeticCRS: ") +
+                                   e.what());
+        }
+    }
+
+    throw ParsingException(
+        concat("unhandled CS type: ", cs->getWKT2Type(true)));
+}
+
+// ---------------------------------------------------------------------------
+
+CRSNNPtr WKTParser::Private::buildDerivedGeodeticCRS(const WKTNodeNNPtr &node) {
+    const auto *nodeP = node->GP();
+    auto &baseGeodCRSNode = nodeP->lookForChild(WKTConstants::BASEGEODCRS,
+                                                WKTConstants::BASEGEOGCRS);
+    // given the constraints enforced on calling code path
+    assert(!isNull(baseGeodCRSNode));
+
+    auto baseGeodCRS = buildGeodeticCRS(baseGeodCRSNode);
+
+    auto &derivingConversionNode =
+        nodeP->lookForChild(WKTConstants::DERIVINGCONVERSION);
+    if (isNull(derivingConversionNode)) {
+        ThrowMissing(WKTConstants::DERIVINGCONVERSION);
+    }
+    auto derivingConversion = buildConversion(
+        derivingConversionNode, UnitOfMeasure::NONE, UnitOfMeasure::NONE);
+
+    auto &csNode = nodeP->lookForChild(WKTConstants::CS);
+    if (isNull(csNode)) {
+        ThrowMissing(WKTConstants::CS);
+    }
+    auto cs = buildCS(csNode, node, UnitOfMeasure::NONE);
+
+    auto ellipsoidalCS = nn_dynamic_pointer_cast<EllipsoidalCS>(cs);
+    if (ellipsoidalCS) {
+        return DerivedGeographicCRS::create(buildProperties(node), baseGeodCRS,
+                                            derivingConversion,
+                                            NN_NO_CHECK(ellipsoidalCS));
+    } else if (ci_equal(nodeP->value(), WKTConstants::GEOGCRS)) {
+        // This is a WKT2-2018 GeographicCRS. An ellipsoidal CS is expected
+        throw ParsingException(concat("ellipsoidal CS expected, but found ",
+                                      cs->getWKT2Type(true)));
+    }
+
+    auto cartesianCS = nn_dynamic_pointer_cast<CartesianCS>(cs);
+    if (cartesianCS) {
+        if (cartesianCS->axisList().size() != 3) {
+            throw ParsingException(
+                "Cartesian CS for a GeodeticCRS should have 3 axis");
+        }
+        return DerivedGeodeticCRS::create(buildProperties(node), baseGeodCRS,
+                                          derivingConversion,
+                                          NN_NO_CHECK(cartesianCS));
+    }
+
+    auto sphericalCS = nn_dynamic_pointer_cast<SphericalCS>(cs);
+    if (sphericalCS) {
+        return DerivedGeodeticCRS::create(buildProperties(node), baseGeodCRS,
+                                          derivingConversion,
+                                          NN_NO_CHECK(sphericalCS));
+    }
+
+    throw ParsingException(
+        concat("unhandled CS type: ", cs->getWKT2Type(true)));
+}
+
+// ---------------------------------------------------------------------------
+
+UnitOfMeasure WKTParser::Private::guessUnitForParameter(
+    const std::string &paramName, const UnitOfMeasure &defaultLinearUnit,
+    const UnitOfMeasure &defaultAngularUnit) {
+    UnitOfMeasure unit;
+    // scale must be first because of 'Scale factor on pseudo standard parallel'
+    if (ci_find(paramName, "scale") != std::string::npos) {
+        unit = UnitOfMeasure::SCALE_UNITY;
+    } else if (ci_find(paramName, "latitude") != std::string::npos ||
+               ci_find(paramName, "longitude") != std::string::npos ||
+               ci_find(paramName, "meridian") != std::string::npos ||
+               ci_find(paramName, "parallel") != std::string::npos ||
+               ci_find(paramName, "azimuth") != std::string::npos ||
+               ci_find(paramName, "angle") != std::string::npos ||
+               ci_find(paramName, "heading") != std::string::npos) {
+        unit = defaultAngularUnit;
+    } else if (ci_find(paramName, "easting") != std::string::npos ||
+               ci_find(paramName, "northing") != std::string::npos ||
+               ci_find(paramName, "height") != std::string::npos) {
+        unit = defaultLinearUnit;
+    }
+    return unit;
+}
+
+// ---------------------------------------------------------------------------
+
+void WKTParser::Private::consumeParameters(
+    const WKTNodeNNPtr &node, bool isAbridged,
+    std::vector<OperationParameterNNPtr> &parameters,
+    std::vector<ParameterValueNNPtr> &values,
+    const UnitOfMeasure &defaultLinearUnit,
+    const UnitOfMeasure &defaultAngularUnit) {
+    for (const auto &childNode : node->GP()->children()) {
+        const auto &childNodeChildren = childNode->GP()->children();
+        if (ci_equal(childNode->GP()->value(), WKTConstants::PARAMETER)) {
+            if (childNodeChildren.size() < 2) {
+                ThrowNotEnoughChildren(childNode->GP()->value());
+            }
+            parameters.push_back(
+                OperationParameter::create(buildProperties(childNode)));
+            const auto &paramValue = childNodeChildren[1]->GP()->value();
+            if (!paramValue.empty() && paramValue[0] == '"') {
+                values.push_back(
+                    ParameterValue::create(stripQuotes(childNodeChildren[1])));
+            } else {
+                try {
+                    double val = asDouble(childNodeChildren[1]);
+                    auto unit = buildUnitInSubNode(childNode);
+                    if (unit == UnitOfMeasure::NONE) {
+                        const auto &paramName =
+                            childNodeChildren[0]->GP()->value();
+                        unit = guessUnitForParameter(
+                            paramName, defaultLinearUnit, defaultAngularUnit);
+                    }
+
+                    if (isAbridged) {
+                        const auto &paramName = parameters.back()->nameStr();
+                        int paramEPSGCode = 0;
+                        const auto &paramIds = parameters.back()->identifiers();
+                        if (paramIds.size() == 1 &&
+                            ci_equal(*(paramIds[0]->codeSpace()),
+                                     Identifier::EPSG)) {
+                            paramEPSGCode = ::atoi(paramIds[0]->code().c_str());
+                        }
+                        const common::UnitOfMeasure *pUnit = nullptr;
+                        if (OperationParameterValue::convertFromAbridged(
+                                paramName, val, pUnit, paramEPSGCode)) {
+                            unit = *pUnit;
+                            parameters.back() = OperationParameter::create(
+                                buildProperties(childNode)
+                                    .set(Identifier::CODESPACE_KEY,
+                                         Identifier::EPSG)
+                                    .set(Identifier::CODE_KEY, paramEPSGCode));
+                        }
+                    }
+
+                    values.push_back(
+                        ParameterValue::create(Measure(val, unit)));
+                } catch (const std::exception &) {
+                    throw ParsingException(concat(
+                        "unhandled parameter value type : ", paramValue));
+                }
+            }
+        } else if (ci_equal(childNode->GP()->value(),
+                            WKTConstants::PARAMETERFILE)) {
+            if (childNodeChildren.size() < 2) {
+                ThrowNotEnoughChildren(childNode->GP()->value());
+            }
+            parameters.push_back(
+                OperationParameter::create(buildProperties(childNode)));
+            values.push_back(ParameterValue::createFilename(
+                stripQuotes(childNodeChildren[1])));
+        }
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+ConversionNNPtr
+WKTParser::Private::buildConversion(const WKTNodeNNPtr &node,
+                                    const UnitOfMeasure &defaultLinearUnit,
+                                    const UnitOfMeasure &defaultAngularUnit) {
+    auto &methodNode = node->GP()->lookForChild(WKTConstants::METHOD,
+                                                WKTConstants::PROJECTION);
+    if (isNull(methodNode)) {
+        ThrowMissing(WKTConstants::METHOD);
+    }
+    if (methodNode->GP()->childrenSize() == 0) {
+        ThrowNotEnoughChildren(WKTConstants::METHOD);
+    }
+
+    std::vector<OperationParameterNNPtr> parameters;
+    std::vector<ParameterValueNNPtr> values;
+    consumeParameters(node, false, parameters, values, defaultLinearUnit,
+                      defaultAngularUnit);
+
+    return Conversion::create(buildProperties(node),
+                              buildProperties(methodNode), parameters, values);
+}
+
+// ---------------------------------------------------------------------------
+
+CoordinateOperationNNPtr
+WKTParser::Private::buildCoordinateOperation(const WKTNodeNNPtr &node) {
+    const auto *nodeP = node->GP();
+    auto &methodNode = nodeP->lookForChild(WKTConstants::METHOD);
+    if (isNull(methodNode)) {
+        ThrowMissing(WKTConstants::METHOD);
+    }
+    if (methodNode->GP()->childrenSize() == 0) {
+        ThrowNotEnoughChildren(WKTConstants::METHOD);
+    }
+
+    auto &sourceCRSNode = nodeP->lookForChild(WKTConstants::SOURCECRS);
+    if (/*isNull(sourceCRSNode) ||*/ sourceCRSNode->GP()->childrenSize() != 1) {
+        ThrowMissing(WKTConstants::SOURCECRS);
+    }
+    auto sourceCRS = buildCRS(sourceCRSNode->GP()->children()[0]);
+    if (!sourceCRS) {
+        throw ParsingException("Invalid content in SOURCECRS node");
+    }
+
+    auto &targetCRSNode = nodeP->lookForChild(WKTConstants::TARGETCRS);
+    if (/*isNull(targetCRSNode) ||*/ targetCRSNode->GP()->childrenSize() != 1) {
+        ThrowMissing(WKTConstants::TARGETCRS);
+    }
+    auto targetCRS = buildCRS(targetCRSNode->GP()->children()[0]);
+    if (!targetCRS) {
+        throw ParsingException("Invalid content in TARGETCRS node");
+    }
+
+    auto &interpolationCRSNode =
+        nodeP->lookForChild(WKTConstants::INTERPOLATIONCRS);
+    CRSPtr interpolationCRS;
+    if (/*!isNull(interpolationCRSNode) && */ interpolationCRSNode->GP()
+            ->childrenSize() == 1) {
+        interpolationCRS = buildCRS(interpolationCRSNode->GP()->children()[0]);
+    }
+
+    std::vector<OperationParameterNNPtr> parameters;
+    std::vector<ParameterValueNNPtr> values;
+    auto defaultLinearUnit = UnitOfMeasure::NONE;
+    auto defaultAngularUnit = UnitOfMeasure::NONE;
+    consumeParameters(node, false, parameters, values, defaultLinearUnit,
+                      defaultAngularUnit);
+
+    std::vector<PositionalAccuracyNNPtr> accuracies;
+    auto &accuracyNode = nodeP->lookForChild(WKTConstants::OPERATIONACCURACY);
+    if (/*!isNull(accuracyNode) && */ accuracyNode->GP()->childrenSize() == 1) {
+        accuracies.push_back(PositionalAccuracy::create(
+            stripQuotes(accuracyNode->GP()->children()[0])));
+    }
+
+    return util::nn_static_pointer_cast<CoordinateOperation>(
+        Transformation::create(buildProperties(node), NN_NO_CHECK(sourceCRS),
+                               NN_NO_CHECK(targetCRS), interpolationCRS,
+                               buildProperties(methodNode), parameters, values,
+                               accuracies));
+}
+
+// ---------------------------------------------------------------------------
+
+ConcatenatedOperationNNPtr
+WKTParser::Private::buildConcatenatedOperation(const WKTNodeNNPtr &node) {
+    std::vector<CoordinateOperationNNPtr> operations;
+    for (const auto &childNode : node->GP()->children()) {
+        if (ci_equal(childNode->GP()->value(), WKTConstants::STEP)) {
+            if (childNode->GP()->childrenSize() != 1) {
+                throw ParsingException("Invalid content in STEP node");
+            }
+            auto op = nn_dynamic_pointer_cast<CoordinateOperation>(
+                build(childNode->GP()->children()[0]));
+            if (!op) {
+                throw ParsingException("Invalid content in STEP node");
+            }
+            operations.emplace_back(NN_NO_CHECK(op));
+        }
+    }
+    try {
+        return ConcatenatedOperation::create(
+            buildProperties(node), operations,
+            std::vector<PositionalAccuracyNNPtr>());
+    } catch (const InvalidOperation &e) {
+        throw ParsingException(
+            std::string("Cannot build concatenated operation: ") + e.what());
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+bool WKTParser::Private::hasWebMercPROJ4String(
+    const WKTNodeNNPtr &projCRSNode, const WKTNodeNNPtr &projectionNode) {
+    if (projectionNode->GP()->childrenSize() == 0) {
+        ThrowNotEnoughChildren(WKTConstants::PROJECTION);
+    }
+    const std::string wkt1ProjectionName =
+        stripQuotes(projectionNode->GP()->children()[0]);
+
+    auto &extensionNode = projCRSNode->lookForChild(WKTConstants::EXTENSION);
+
+    if (metadata::Identifier::isEquivalentName(wkt1ProjectionName.c_str(),
+                                               "Mercator_1SP") &&
+        projCRSNode->countChildrenOfName("center_latitude") == 0) {
+
+        // Hack to detect the hacky way of encodign webmerc in GDAL WKT1
+        // with a EXTENSION["PROJ4", "+proj=merc +a=6378137 +b=6378137
+        // +lat_ts=0.0 +lon_0=0.0 +x_0=0.0 +y_0=0 +k=1.0 +units=m
+        // +nadgrids=@null +wktext +no_defs"] node
+        if (extensionNode && extensionNode->GP()->childrenSize() == 2 &&
+            ci_equal(stripQuotes(extensionNode->GP()->children()[0]),
+                     "PROJ4")) {
+            std::string projString =
+                stripQuotes(extensionNode->GP()->children()[1]);
+            if (projString.find("+proj=merc") != std::string::npos &&
+                projString.find("+a=6378137") != std::string::npos &&
+                projString.find("+b=6378137") != std::string::npos &&
+                projString.find("+lon_0=0") != std::string::npos &&
+                projString.find("+x_0=0") != std::string::npos &&
+                projString.find("+y_0=0") != std::string::npos &&
+                projString.find("+nadgrids=@null") != std::string::npos &&
+                (projString.find("+lat_ts=") == std::string::npos ||
+                 projString.find("+lat_ts=0") != std::string::npos) &&
+                (projString.find("+k=") == std::string::npos ||
+                 projString.find("+k=1") != std::string::npos) &&
+                (projString.find("+units=") == std::string::npos ||
+                 projString.find("+units=m") != std::string::npos)) {
+                return true;
+            }
+        }
+    }
+    return false;
+}
+
+// ---------------------------------------------------------------------------
+
+ConversionNNPtr WKTParser::Private::buildProjectionFromESRI(
+    const WKTNodeNNPtr &projCRSNode, const WKTNodeNNPtr &projectionNode,
+    const UnitOfMeasure &defaultLinearUnit,
+    const UnitOfMeasure &defaultAngularUnit) {
+    const std::string esriProjectionName =
+        stripQuotes(projectionNode->GP()->children()[0]);
+
+    // Lambert_Conformal_Conic or Krovak may map to different WKT2 methods
+    // depending
+    // on the parameters / their values
+    const auto esriMappings = getMappingsFromESRI(esriProjectionName);
+    if (esriMappings.empty()) {
+        return buildProjectionStandard(projCRSNode, projectionNode,
+                                       defaultLinearUnit, defaultAngularUnit);
+    }
+
+    struct ci_less_struct {
+        bool operator()(const std::string &lhs, const std::string &rhs) const
+            noexcept {
+            return ci_less(lhs, rhs);
+        }
+    };
+
+    // Build a map of present parameters
+    std::map<std::string, std::string, ci_less_struct> mapParamNameToValue;
+    for (const auto &childNode : projCRSNode->GP()->children()) {
+        if (ci_equal(childNode->GP()->value(), WKTConstants::PARAMETER)) {
+            const auto &childNodeChildren = childNode->GP()->children();
+            if (childNodeChildren.size() < 2) {
+                ThrowNotEnoughChildren(WKTConstants::PARAMETER);
+            }
+            const std::string parameterName(stripQuotes(childNodeChildren[0]));
+            const auto &paramValue = childNodeChildren[1]->GP()->value();
+            mapParamNameToValue[parameterName] = paramValue;
+        }
+    }
+
+    // Compare parameters present with the ones expected in the mapping
+    const ESRIMethodMapping *esriMapping = esriMappings[0];
+    int bestMatchCount = -1;
+    for (const auto &mapping : esriMappings) {
+        int matchCount = 0;
+        for (const auto *param = mapping->params; param->esri_name; ++param) {
+            auto iter = mapParamNameToValue.find(param->esri_name);
+            if (iter != mapParamNameToValue.end()) {
+                if (param->wkt2_name == nullptr) {
+                    try {
+                        if (param->fixed_value == io::asDouble(iter->second)) {
+                            matchCount++;
+                        }
+                    } catch (const std::exception &) {
+                    }
+                } else {
+                    matchCount++;
+                }
+            }
+        }
+        if (matchCount > bestMatchCount) {
+            esriMapping = mapping;
+            bestMatchCount = matchCount;
+        }
+    }
+
+    std::map<std::string, const char *> mapWKT2NameToESRIName;
+    for (const auto *param = esriMapping->params; param->esri_name; ++param) {
+        if (param->wkt2_name) {
+            mapWKT2NameToESRIName[param->wkt2_name] = param->esri_name;
+        }
+    }
+
+    const auto *wkt2_mapping = getMapping(esriMapping->wkt2_name);
+    assert(wkt2_mapping);
+    if (ci_equal(esriProjectionName, "Stereographic")) {
+        try {
+            if (std::fabs(io::asDouble(
+                    mapParamNameToValue["Latitude_Of_Origin"])) == 90.0) {
+                wkt2_mapping =
+                    getMapping(EPSG_CODE_METHOD_POLAR_STEREOGRAPHIC_VARIANT_A);
+            }
+        } catch (const std::exception &) {
+        }
+    }
+
+    PropertyMap propertiesMethod;
+    propertiesMethod.set(IdentifiedObject::NAME_KEY, wkt2_mapping->wkt2_name);
+    if (wkt2_mapping->epsg_code != 0) {
+        propertiesMethod.set(Identifier::CODE_KEY, wkt2_mapping->epsg_code);
+        propertiesMethod.set(Identifier::CODESPACE_KEY, Identifier::EPSG);
+    }
+
+    std::vector<OperationParameterNNPtr> parameters;
+    std::vector<ParameterValueNNPtr> values;
+
+    if (wkt2_mapping->epsg_code == EPSG_CODE_METHOD_EQUIDISTANT_CYLINDRICAL &&
+        ci_equal(esriProjectionName, "Plate_Carree")) {
+        // Add a fixed  Latitude of 1st parallel = 0 so as to have all
+        // parameters expected by Equidistant Cylindrical.
+        mapWKT2NameToESRIName[EPSG_NAME_PARAMETER_LATITUDE_1ST_STD_PARALLEL] =
+            "Standard_Parallel_1";
+        mapParamNameToValue["Standard_Parallel_1"] = "0";
+    } else if ((wkt2_mapping->epsg_code ==
+                    EPSG_CODE_METHOD_HOTINE_OBLIQUE_MERCATOR_VARIANT_A ||
+                wkt2_mapping->epsg_code ==
+                    EPSG_CODE_METHOD_HOTINE_OBLIQUE_MERCATOR_VARIANT_B) &&
+               !ci_equal(esriProjectionName,
+                         "Rectified_Skew_Orthomorphic_Natural_Origin") &&
+               !ci_equal(esriProjectionName,
+                         "Rectified_Skew_Orthomorphic_Center")) {
+        // ESRI WKT lacks the angle to skew grid
+        // Take it from the azimuth value
+        mapWKT2NameToESRIName
+            [EPSG_NAME_PARAMETER_ANGLE_RECTIFIED_TO_SKEW_GRID] = "Azimuth";
+    }
+
+    for (int i = 0; wkt2_mapping->params[i] != nullptr; i++) {
+        const auto *paramMapping = wkt2_mapping->params[i];
+
+        auto iter = mapWKT2NameToESRIName.find(paramMapping->wkt2_name);
+        if (iter == mapWKT2NameToESRIName.end()) {
+            continue;
+        }
+        const auto &esriParamName = iter->second;
+        auto iter2 = mapParamNameToValue.find(esriParamName);
+        auto mapParamNameToValueEnd = mapParamNameToValue.end();
+        if (iter2 == mapParamNameToValueEnd) {
+            // In case we don't find a direct match, try the aliases
+            for (iter2 = mapParamNameToValue.begin();
+                 iter2 != mapParamNameToValueEnd; ++iter2) {
+                if (areEquivalentParameters(iter2->first, esriParamName)) {
+                    break;
+                }
+            }
+            if (iter2 == mapParamNameToValueEnd) {
+                continue;
+            }
+        }
+
+        PropertyMap propertiesParameter;
+        propertiesParameter.set(IdentifiedObject::NAME_KEY,
+                                paramMapping->wkt2_name);
+        if (paramMapping->epsg_code != 0) {
+            propertiesParameter.set(Identifier::CODE_KEY,
+                                    paramMapping->epsg_code);
+            propertiesParameter.set(Identifier::CODESPACE_KEY,
+                                    Identifier::EPSG);
+        }
+        parameters.push_back(OperationParameter::create(propertiesParameter));
+
+        try {
+            double val = io::asDouble(iter2->second);
+            auto unit = guessUnitForParameter(
+                paramMapping->wkt2_name, defaultLinearUnit, defaultAngularUnit);
+            values.push_back(ParameterValue::create(Measure(val, unit)));
+        } catch (const std::exception &) {
+            throw ParsingException(
+                concat("unhandled parameter value type : ", iter2->second));
+        }
+    }
+
+    return Conversion::create(
+               PropertyMap().set(IdentifiedObject::NAME_KEY, "unnamed"),
+               propertiesMethod, parameters, values)
+        ->identify();
+}
+
+// ---------------------------------------------------------------------------
+
+ConversionNNPtr
+WKTParser::Private::buildProjection(const WKTNodeNNPtr &projCRSNode,
+                                    const WKTNodeNNPtr &projectionNode,
+                                    const UnitOfMeasure &defaultLinearUnit,
+                                    const UnitOfMeasure &defaultAngularUnit) {
+    if (projectionNode->GP()->childrenSize() == 0) {
+        ThrowNotEnoughChildren(WKTConstants::PROJECTION);
+    }
+    if (esriStyle_) {
+        return buildProjectionFromESRI(projCRSNode, projectionNode,
+                                       defaultLinearUnit, defaultAngularUnit);
+    }
+    return buildProjectionStandard(projCRSNode, projectionNode,
+                                   defaultLinearUnit, defaultAngularUnit);
+}
+
+// ---------------------------------------------------------------------------
+
+std::string
+WKTParser::Private::projectionGetParameter(const WKTNodeNNPtr &projCRSNode,
+                                           const char *paramName) {
+    for (const auto &childNode : projCRSNode->GP()->children()) {
+        if (ci_equal(childNode->GP()->value(), WKTConstants::PARAMETER)) {
+            const auto &childNodeChildren = childNode->GP()->children();
+            if (childNodeChildren.size() == 2 &&
+                metadata::Identifier::isEquivalentName(
+                    stripQuotes(childNodeChildren[0]).c_str(), paramName)) {
+                return childNodeChildren[1]->GP()->value();
+            }
+        }
+    }
+    return std::string();
+}
+
+// ---------------------------------------------------------------------------
+
+ConversionNNPtr WKTParser::Private::buildProjectionStandard(
+    const WKTNodeNNPtr &projCRSNode, const WKTNodeNNPtr &projectionNode,
+    const UnitOfMeasure &defaultLinearUnit,
+    const UnitOfMeasure &defaultAngularUnit) {
+    std::string wkt1ProjectionName =
+        stripQuotes(projectionNode->GP()->children()[0]);
+
+    std::vector<OperationParameterNNPtr> parameters;
+    std::vector<ParameterValueNNPtr> values;
+    bool tryToIdentifyWKT1Method = true;
+
+    auto &extensionNode = projCRSNode->lookForChild(WKTConstants::EXTENSION);
+    const auto &extensionChildren = extensionNode->GP()->children();
+
+    bool gdal_3026_hack = false;
+    if (metadata::Identifier::isEquivalentName(wkt1ProjectionName.c_str(),
+                                               "Mercator_1SP") &&
+        projectionGetParameter(projCRSNode, "center_latitude").empty()) {
+
+        // Hack for https://trac.osgeo.org/gdal/ticket/3026
+        std::string lat0(
+            projectionGetParameter(projCRSNode, "latitude_of_origin"));
+        if (!lat0.empty() && lat0 != "0" && lat0 != "0.0") {
+            wkt1ProjectionName = "Mercator_2SP";
+            gdal_3026_hack = true;
+        } else {
+            // The latitude of origin, which should always be zero, is
+            // missing
+            // in GDAL WKT1, but provisionned in the EPSG Mercator_1SP
+            // definition,
+            // so add it manually.
+            PropertyMap propertiesParameter;
+            propertiesParameter.set(IdentifiedObject::NAME_KEY,
+                                    "Latitude of natural origin");
+            propertiesParameter.set(Identifier::CODE_KEY, 8801);
+            propertiesParameter.set(Identifier::CODESPACE_KEY,
+                                    Identifier::EPSG);
+            parameters.push_back(
+                OperationParameter::create(propertiesParameter));
+            values.push_back(
+                ParameterValue::create(Measure(0, UnitOfMeasure::DEGREE)));
+        }
+
+    } else if (metadata::Identifier::isEquivalentName(
+                   wkt1ProjectionName.c_str(), "Polar_Stereographic")) {
+        std::map<std::string, Measure> mapParameters;
+        for (const auto &childNode : projCRSNode->GP()->children()) {
+            const auto &childNodeChildren = childNode->GP()->children();
+            if (ci_equal(childNode->GP()->value(), WKTConstants::PARAMETER) &&
+                childNodeChildren.size() == 2) {
+                const std::string wkt1ParameterName(
+                    stripQuotes(childNodeChildren[0]));
+                try {
+                    double val = asDouble(childNodeChildren[1]);
+                    auto unit = guessUnitForParameter(wkt1ParameterName,
+                                                      defaultLinearUnit,
+                                                      defaultAngularUnit);
+                    mapParameters.insert(std::pair<std::string, Measure>(
+                        tolower(wkt1ParameterName), Measure(val, unit)));
+                } catch (const std::exception &) {
+                }
+            }
+        }
+
+        Measure latitudeOfOrigin = mapParameters["latitude_of_origin"];
+        Measure centralMeridian = mapParameters["central_meridian"];
+        Measure scaleFactorFromMap = mapParameters["scale_factor"];
+        Measure scaleFactor((scaleFactorFromMap.unit() == UnitOfMeasure::NONE)
+                                ? Measure(1.0, UnitOfMeasure::SCALE_UNITY)
+                                : scaleFactorFromMap);
+        Measure falseEasting = mapParameters["false_easting"];
+        Measure falseNorthing = mapParameters["false_northing"];
+        if (latitudeOfOrigin.unit() != UnitOfMeasure::NONE &&
+            scaleFactor.getSIValue() == 1.0) {
+            return Conversion::createPolarStereographicVariantB(
+                PropertyMap().set(IdentifiedObject::NAME_KEY, "unnamed"),
+                Angle(latitudeOfOrigin.value(), latitudeOfOrigin.unit()),
+                Angle(centralMeridian.value(), centralMeridian.unit()),
+                Length(falseEasting.value(), falseEasting.unit()),
+                Length(falseNorthing.value(), falseNorthing.unit()));
+        }
+
+        if (latitudeOfOrigin.unit() != UnitOfMeasure::NONE &&
+            std::fabs(std::fabs(latitudeOfOrigin.convertToUnit(
+                          UnitOfMeasure::DEGREE)) -
+                      90.0) < 1e-10) {
+            return Conversion::createPolarStereographicVariantA(
+                PropertyMap().set(IdentifiedObject::NAME_KEY, "unnamed"),
+                Angle(latitudeOfOrigin.value(), latitudeOfOrigin.unit()),
+                Angle(centralMeridian.value(), centralMeridian.unit()),
+                Scale(scaleFactor.value(), scaleFactor.unit()),
+                Length(falseEasting.value(), falseEasting.unit()),
+                Length(falseNorthing.value(), falseNorthing.unit()));
+        }
+
+        tryToIdentifyWKT1Method = false;
+        // Import GDAL PROJ4 extension nodes
+    } else if (extensionChildren.size() == 2 &&
+               ci_equal(stripQuotes(extensionChildren[0]), "PROJ4")) {
+        std::string projString = stripQuotes(extensionChildren[1]);
+        if (starts_with(projString, "+proj=")) {
+            try {
+                auto projObj =
+                    PROJStringParser().createFromPROJString(projString);
+                auto projObjCrs =
+                    nn_dynamic_pointer_cast<ProjectedCRS>(projObj);
+                if (projObjCrs) {
+                    return projObjCrs->derivingConversion();
+                }
+            } catch (const io::ParsingException &) {
+            }
+        }
+    }
+
+    std::string projectionName(wkt1ProjectionName);
+    const MethodMapping *mapping =
+        tryToIdentifyWKT1Method ? getMappingFromWKT1(projectionName) : nullptr;
+
+    // For Krovak, we need to look at axis to decide between the Krovak and
+    // Krovak East-North Oriented methods
+    if (ci_equal(projectionName, "Krovak") &&
+        projCRSNode->countChildrenOfName(WKTConstants::AXIS) == 2 &&
+        &buildAxis(
+             projCRSNode->GP()->lookForChild(WKTConstants::AXIS, 0),
+             defaultLinearUnit, UnitOfMeasure::Type::LINEAR, false,
+             1)->direction() == &AxisDirection::SOUTH &&
+        &buildAxis(
+             projCRSNode->GP()->lookForChild(WKTConstants::AXIS, 1),
+             defaultLinearUnit, UnitOfMeasure::Type::LINEAR, false,
+             2)->direction() == &AxisDirection::WEST) {
+        mapping = getMapping(EPSG_CODE_METHOD_KROVAK);
+    }
+
+    PropertyMap propertiesMethod;
+    if (mapping) {
+        projectionName = mapping->wkt2_name;
+        if (mapping->epsg_code != 0) {
+            propertiesMethod.set(Identifier::CODE_KEY, mapping->epsg_code);
+            propertiesMethod.set(Identifier::CODESPACE_KEY, Identifier::EPSG);
+        }
+    }
+    propertiesMethod.set(IdentifiedObject::NAME_KEY, projectionName);
+
+    for (const auto &childNode : projCRSNode->GP()->children()) {
+        if (ci_equal(childNode->GP()->value(), WKTConstants::PARAMETER)) {
+            const auto &childNodeChildren = childNode->GP()->children();
+            if (childNodeChildren.size() < 2) {
+                ThrowNotEnoughChildren(WKTConstants::PARAMETER);
+            }
+            const auto &paramValue = childNodeChildren[1]->GP()->value();
+
+            PropertyMap propertiesParameter;
+            const std::string wkt1ParameterName(
+                stripQuotes(childNodeChildren[0]));
+            std::string parameterName(wkt1ParameterName);
+            if (gdal_3026_hack) {
+                if (ci_equal(parameterName, "latitude_of_origin")) {
+                    parameterName = "standard_parallel_1";
+                } else if (ci_equal(parameterName, "scale_factor") &&
+                           paramValue == "1") {
+                    continue;
+                }
+            }
+            const auto *paramMapping =
+                mapping ? getMappingFromWKT1(mapping, parameterName) : nullptr;
+            if (mapping &&
+                mapping->epsg_code == EPSG_CODE_METHOD_MERCATOR_VARIANT_B &&
+                ci_equal(parameterName, "latitude_of_origin")) {
+                parameterName = EPSG_NAME_PARAMETER_LATITUDE_OF_NATURAL_ORIGIN;
+                propertiesParameter.set(
+                    Identifier::CODE_KEY,
+                    EPSG_CODE_PARAMETER_LATITUDE_OF_NATURAL_ORIGIN);
+                propertiesParameter.set(Identifier::CODESPACE_KEY,
+                                        Identifier::EPSG);
+            } else if (paramMapping) {
+                parameterName = paramMapping->wkt2_name;
+                if (paramMapping->epsg_code != 0) {
+                    propertiesParameter.set(Identifier::CODE_KEY,
+                                            paramMapping->epsg_code);
+                    propertiesParameter.set(Identifier::CODESPACE_KEY,
+                                            Identifier::EPSG);
+                }
+            }
+            propertiesParameter.set(IdentifiedObject::NAME_KEY, parameterName);
+            parameters.push_back(
+                OperationParameter::create(propertiesParameter));
+            try {
+                double val = io::asDouble(paramValue);
+                auto unit = guessUnitForParameter(
+                    wkt1ParameterName, defaultLinearUnit, defaultAngularUnit);
+                values.push_back(ParameterValue::create(Measure(val, unit)));
+            } catch (const std::exception &) {
+                throw ParsingException(
+                    concat("unhandled parameter value type : ", paramValue));
+            }
+        }
+    }
+
+    return Conversion::create(
+               PropertyMap().set(IdentifiedObject::NAME_KEY, "unnamed"),
+               propertiesMethod, parameters, values)
+        ->identify();
+}
+
+// ---------------------------------------------------------------------------
+
+static ProjectedCRSNNPtr createPseudoMercator(const PropertyMap &props) {
+    auto conversion = Conversion::createPopularVisualisationPseudoMercator(
+        PropertyMap().set(IdentifiedObject::NAME_KEY, "unnamed"), Angle(0),
+        Angle(0), Length(0), Length(0));
+    return ProjectedCRS::create(
+        props, GeographicCRS::EPSG_4326, conversion,
+        CartesianCS::createEastingNorthing(UnitOfMeasure::METRE));
+}
+
+// ---------------------------------------------------------------------------
+
+ProjectedCRSNNPtr
+WKTParser::Private::buildProjectedCRS(const WKTNodeNNPtr &node) {
+
+    const auto *nodeP = node->GP();
+    auto &conversionNode = nodeP->lookForChild(WKTConstants::CONVERSION);
+    auto &projectionNode = nodeP->lookForChild(WKTConstants::PROJECTION);
+    if (isNull(conversionNode) && isNull(projectionNode)) {
+        ThrowMissing(WKTConstants::CONVERSION);
+    }
+
+    auto &baseGeodCRSNode =
+        nodeP->lookForChild(WKTConstants::BASEGEODCRS,
+                            WKTConstants::BASEGEOGCRS, WKTConstants::GEOGCS);
+    if (isNull(baseGeodCRSNode)) {
+        throw ParsingException(
+            "Missing BASEGEODCRS / BASEGEOGCRS / GEOGCS node");
+    }
+    auto baseGeodCRS = buildGeodeticCRS(baseGeodCRSNode);
+
+    auto props = buildProperties(node);
+
+    const std::string projCRSName = stripQuotes(nodeP->children()[0]);
+    if (esriStyle_ && dbContext_) {
+        // It is likely that the ESRI definition of EPSG:32661 (UPS North) &
+        // EPSG:32761 (UPS South) uses the easting-northing order, instead
+        // of the EPSG northing-easting order
+        // so don't substitue names to avoid confusion.
+        if (projCRSName == "UPS_North") {
+            props.set(IdentifiedObject::NAME_KEY, "WGS 84 / UPS North (E,N)");
+        } else if (projCRSName == "UPS_South") {
+            props.set(IdentifiedObject::NAME_KEY, "WGS 84 / UPS South (E,N)");
+        } else {
+            std::string outTableName;
+            std::string authNameFromAlias;
+            std::string codeFromAlias;
+            auto authFactory = AuthorityFactory::create(NN_NO_CHECK(dbContext_),
+                                                        std::string());
+            auto officialName = authFactory->getOfficialNameFromAlias(
+                projCRSName, "projected_crs", "ESRI", false, outTableName,
+                authNameFromAlias, codeFromAlias);
+            if (!officialName.empty()) {
+                props.set(IdentifiedObject::NAME_KEY, officialName);
+            }
+        }
+    }
+
+    if (isNull(conversionNode) && hasWebMercPROJ4String(node, projectionNode)) {
+        toWGS84Parameters_.clear();
+        return createPseudoMercator(props);
+    }
+
+    // WGS_84_Pseudo_Mercator: Particular case for corrupted ESRI WKT generated
+    // by older GDAL versions
+    // https://trac.osgeo.org/gdal/changeset/30732
+    // WGS_1984_Web_Mercator: deprecated ESRI:102113
+    if (metadata::Identifier::isEquivalentName(projCRSName.c_str(),
+                                               "WGS_84_Pseudo_Mercator") ||
+        metadata::Identifier::isEquivalentName(projCRSName.c_str(),
+                                               "WGS_1984_Web_Mercator")) {
+        toWGS84Parameters_.clear();
+        return createPseudoMercator(props);
+    }
+
+    auto linearUnit = buildUnitInSubNode(node, UnitOfMeasure::Type::LINEAR);
+    auto angularUnit = baseGeodCRS->coordinateSystem()->axisList()[0]->unit();
+
+    auto conversion =
+        !isNull(conversionNode)
+            ? buildConversion(conversionNode, linearUnit, angularUnit)
+            : buildProjection(node, projectionNode, linearUnit, angularUnit);
+
+    auto &csNode = nodeP->lookForChild(WKTConstants::CS);
+    const auto &nodeValue = nodeP->value();
+    if (isNull(csNode) && !ci_equal(nodeValue, WKTConstants::PROJCS) &&
+        !ci_equal(nodeValue, WKTConstants::BASEPROJCRS)) {
+        ThrowMissing(WKTConstants::CS);
+    }
+    auto cs = buildCS(csNode, node, UnitOfMeasure::NONE);
+    auto cartesianCS = nn_dynamic_pointer_cast<CartesianCS>(cs);
+
+    // No explicit AXIS node ? (WKT1)
+    if (isNull(nodeP->lookForChild(WKTConstants::AXIS))) {
+        props.set("IMPLICIT_CS", true);
+    }
+
+    if (isNull(csNode) && node->countChildrenOfName(WKTConstants::AXIS) == 0) {
+
+        const auto methodCode = conversion->method()->getEPSGCode();
+        // Krovak south oriented ?
+        if (methodCode == EPSG_CODE_METHOD_KROVAK) {
+            cartesianCS =
+                CartesianCS::create(
+                    PropertyMap(),
+                    CoordinateSystemAxis::create(
+                        util::PropertyMap().set(IdentifiedObject::NAME_KEY,
+                                                AxisName::Southing),
+                        emptyString, AxisDirection::SOUTH, linearUnit),
+                    CoordinateSystemAxis::create(
+                        util::PropertyMap().set(IdentifiedObject::NAME_KEY,
+                                                AxisName::Westing),
+                        emptyString, AxisDirection::WEST, linearUnit))
+                    .as_nullable();
+        } else if (methodCode ==
+                       EPSG_CODE_METHOD_POLAR_STEREOGRAPHIC_VARIANT_A ||
+                   methodCode ==
+                       EPSG_CODE_METHOD_LAMBERT_AZIMUTHAL_EQUAL_AREA) {
+            // It is likely that the ESRI definition of EPSG:32661 (UPS North) &
+            // EPSG:32761 (UPS South) uses the easting-northing order, instead
+            // of the EPSG northing-easting order.
+            // Same for WKT1_GDAL
+            const double lat0 = conversion->parameterValueNumeric(
+                EPSG_CODE_PARAMETER_LATITUDE_OF_NATURAL_ORIGIN,
+                common::UnitOfMeasure::DEGREE);
+            if (std::fabs(lat0 - 90) < 1e-10) {
+                cartesianCS =
+                    CartesianCS::createNorthPoleEastingSouthNorthingSouth(
+                        linearUnit)
+                        .as_nullable();
+            } else if (std::fabs(lat0 - -90) < 1e-10) {
+                cartesianCS =
+                    CartesianCS::createSouthPoleEastingNorthNorthingNorth(
+                        linearUnit)
+                        .as_nullable();
+            }
+        } else if (methodCode ==
+                   EPSG_CODE_METHOD_POLAR_STEREOGRAPHIC_VARIANT_B) {
+            const double lat_ts = conversion->parameterValueNumeric(
+                EPSG_CODE_PARAMETER_LATITUDE_STD_PARALLEL,
+                common::UnitOfMeasure::DEGREE);
+            if (lat_ts > 0) {
+                cartesianCS =
+                    CartesianCS::createNorthPoleEastingSouthNorthingSouth(
+                        linearUnit)
+                        .as_nullable();
+            } else if (lat_ts < 0) {
+                cartesianCS =
+                    CartesianCS::createSouthPoleEastingNorthNorthingNorth(
+                        linearUnit)
+                        .as_nullable();
+            }
+        } else if (methodCode ==
+                   EPSG_CODE_METHOD_TRANSVERSE_MERCATOR_SOUTH_ORIENTATED) {
+            cartesianCS =
+                CartesianCS::createWestingSouthing(linearUnit).as_nullable();
+        }
+    }
+    if (!cartesianCS) {
+        ThrowNotExpectedCSType("Cartesian");
+    }
+
+    addExtensionProj4ToProp(nodeP, props);
+
+    return ProjectedCRS::create(props, baseGeodCRS, conversion,
+                                NN_NO_CHECK(cartesianCS));
+}
+
+// ---------------------------------------------------------------------------
+
+void WKTParser::Private::parseDynamic(const WKTNodeNNPtr &dynamicNode,
+                                      double &frameReferenceEpoch,
+                                      util::optional<std::string> &modelName) {
+    auto &frameEpochNode = dynamicNode->lookForChild(WKTConstants::FRAMEEPOCH);
+    const auto &frameEpochChildren = frameEpochNode->GP()->children();
+    if (frameEpochChildren.empty()) {
+        ThrowMissing(WKTConstants::FRAMEEPOCH);
+    }
+    try {
+        frameReferenceEpoch = asDouble(frameEpochChildren[0]);
+    } catch (const std::exception &) {
+        throw ParsingException("Invalid FRAMEEPOCH node");
+    }
+    auto &modelNode = dynamicNode->GP()->lookForChild(
+        WKTConstants::MODEL, WKTConstants::VELOCITYGRID);
+    const auto &modelChildren = modelNode->GP()->children();
+    if (modelChildren.size() == 1) {
+        modelName = stripQuotes(modelChildren[0]);
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+VerticalReferenceFrameNNPtr WKTParser::Private::buildVerticalReferenceFrame(
+    const WKTNodeNNPtr &node, const WKTNodeNNPtr &dynamicNode) {
+
+    if (!isNull(dynamicNode)) {
+        double frameReferenceEpoch = 0.0;
+        util::optional<std::string> modelName;
+        parseDynamic(dynamicNode, frameReferenceEpoch, modelName);
+        return DynamicVerticalReferenceFrame::create(
+            buildProperties(node), getAnchor(node),
+            optional<RealizationMethod>(),
+            common::Measure(frameReferenceEpoch, common::UnitOfMeasure::YEAR),
+            modelName);
+    }
+
+    // WKT1 VERT_DATUM has a datum type after the datum name that we ignore.
+    return VerticalReferenceFrame::create(buildProperties(node),
+                                          getAnchor(node));
+}
+
+// ---------------------------------------------------------------------------
+
+TemporalDatumNNPtr
+WKTParser::Private::buildTemporalDatum(const WKTNodeNNPtr &node) {
+    const auto *nodeP = node->GP();
+    auto &calendarNode = nodeP->lookForChild(WKTConstants::CALENDAR);
+    std::string calendar = TemporalDatum::CALENDAR_PROLEPTIC_GREGORIAN;
+    const auto &calendarChildren = calendarNode->GP()->children();
+    if (calendarChildren.size() == 1) {
+        calendar = stripQuotes(calendarChildren[0]);
+    }
+
+    auto &timeOriginNode = nodeP->lookForChild(WKTConstants::TIMEORIGIN);
+    std::string originStr;
+    const auto &timeOriginNodeChildren = timeOriginNode->GP()->children();
+    if (timeOriginNodeChildren.size() == 1) {
+        originStr = stripQuotes(timeOriginNodeChildren[0]);
+    }
+    auto origin = DateTime::create(originStr);
+    return TemporalDatum::create(buildProperties(node), origin, calendar);
+}
+
+// ---------------------------------------------------------------------------
+
+EngineeringDatumNNPtr
+WKTParser::Private::buildEngineeringDatum(const WKTNodeNNPtr &node) {
+    return EngineeringDatum::create(buildProperties(node), getAnchor(node));
+}
+
+// ---------------------------------------------------------------------------
+
+ParametricDatumNNPtr
+WKTParser::Private::buildParametricDatum(const WKTNodeNNPtr &node) {
+    return ParametricDatum::create(buildProperties(node), getAnchor(node));
+}
+
+// ---------------------------------------------------------------------------
+
+CRSNNPtr WKTParser::Private::buildVerticalCRS(const WKTNodeNNPtr &node) {
+    const auto *nodeP = node->GP();
+    auto &datumNode =
+        nodeP->lookForChild(WKTConstants::VDATUM, WKTConstants::VERT_DATUM,
+                            WKTConstants::VERTICALDATUM, WKTConstants::VRF);
+    auto &ensembleNode = nodeP->lookForChild(WKTConstants::ENSEMBLE);
+    if (isNull(datumNode) && isNull(ensembleNode)) {
+        throw ParsingException("Missing VDATUM or ENSEMBLE node");
+    }
+
+    auto &dynamicNode = nodeP->lookForChild(WKTConstants::DYNAMIC);
+    auto datum =
+        !isNull(datumNode)
+            ? buildVerticalReferenceFrame(datumNode, dynamicNode).as_nullable()
+            : nullptr;
+    auto datumEnsemble =
+        !isNull(ensembleNode)
+            ? buildDatumEnsemble(ensembleNode, nullptr, false).as_nullable()
+            : nullptr;
+
+    auto &csNode = nodeP->lookForChild(WKTConstants::CS);
+    const auto &nodeValue = nodeP->value();
+    if (isNull(csNode) && !ci_equal(nodeValue, WKTConstants::VERT_CS) &&
+        !ci_equal(nodeValue, WKTConstants::BASEVERTCRS)) {
+        ThrowMissing(WKTConstants::CS);
+    }
+    auto cs = buildCS(csNode, node, UnitOfMeasure::NONE);
+    auto verticalCS = nn_dynamic_pointer_cast<VerticalCS>(cs);
+    if (!verticalCS) {
+        ThrowNotExpectedCSType("vertical");
+    }
+
+    auto crs = nn_static_pointer_cast<CRS>(VerticalCRS::create(
+        buildProperties(node), datum, datumEnsemble, NN_NO_CHECK(verticalCS)));
+
+    if (!isNull(datumNode)) {
+        auto &extensionNode = datumNode->lookForChild(WKTConstants::EXTENSION);
+        const auto &extensionChildren = extensionNode->GP()->children();
+        if (extensionChildren.size() == 2) {
+            if (ci_equal(stripQuotes(extensionChildren[0]), "PROJ4_GRIDS")) {
+                std::string transformationName(crs->nameStr());
+                if (!ends_with(transformationName, " height")) {
+                    transformationName += " height";
+                }
+                transformationName += " to WGS84 ellipsoidal height";
+                auto transformation =
+                    Transformation::createGravityRelatedHeightToGeographic3D(
+                        PropertyMap().set(IdentifiedObject::NAME_KEY,
+                                          transformationName),
+                        crs, GeographicCRS::EPSG_4979,
+                        stripQuotes(extensionChildren[1]),
+                        std::vector<PositionalAccuracyNNPtr>());
+                return nn_static_pointer_cast<CRS>(BoundCRS::create(
+                    crs, GeographicCRS::EPSG_4979, transformation));
+            }
+        }
+    }
+
+    return crs;
+}
+
+// ---------------------------------------------------------------------------
+
+DerivedVerticalCRSNNPtr
+WKTParser::Private::buildDerivedVerticalCRS(const WKTNodeNNPtr &node) {
+    const auto *nodeP = node->GP();
+    auto &baseVertCRSNode = nodeP->lookForChild(WKTConstants::BASEVERTCRS);
+    // given the constraints enforced on calling code path
+    assert(!isNull(baseVertCRSNode));
+
+    auto baseVertCRS_tmp = buildVerticalCRS(baseVertCRSNode);
+    auto baseVertCRS = NN_NO_CHECK(baseVertCRS_tmp->extractVerticalCRS());
+
+    auto &derivingConversionNode =
+        nodeP->lookForChild(WKTConstants::DERIVINGCONVERSION);
+    if (isNull(derivingConversionNode)) {
+        ThrowMissing(WKTConstants::DERIVINGCONVERSION);
+    }
+    auto derivingConversion = buildConversion(
+        derivingConversionNode, UnitOfMeasure::NONE, UnitOfMeasure::NONE);
+
+    auto &csNode = nodeP->lookForChild(WKTConstants::CS);
+    if (isNull(csNode)) {
+        ThrowMissing(WKTConstants::CS);
+    }
+    auto cs = buildCS(csNode, node, UnitOfMeasure::NONE);
+
+    auto verticalCS = nn_dynamic_pointer_cast<VerticalCS>(cs);
+    if (!verticalCS) {
+        throw ParsingException(
+            concat("vertical CS expected, but found ", cs->getWKT2Type(true)));
+    }
+
+    return DerivedVerticalCRS::create(buildProperties(node), baseVertCRS,
+                                      derivingConversion,
+                                      NN_NO_CHECK(verticalCS));
+}
+
+// ---------------------------------------------------------------------------
+
+CompoundCRSNNPtr
+WKTParser::Private::buildCompoundCRS(const WKTNodeNNPtr &node) {
+    std::vector<CRSNNPtr> components;
+    for (const auto &child : node->GP()->children()) {
+        auto crs = buildCRS(child);
+        if (crs) {
+            components.push_back(NN_NO_CHECK(crs));
+        }
+    }
+    return CompoundCRS::create(buildProperties(node), components);
+}
+
+// ---------------------------------------------------------------------------
+
+BoundCRSNNPtr WKTParser::Private::buildBoundCRS(const WKTNodeNNPtr &node) {
+    const auto *nodeP = node->GP();
+    auto &abridgedNode =
+        nodeP->lookForChild(WKTConstants::ABRIDGEDTRANSFORMATION);
+    if (isNull(abridgedNode)) {
+        ThrowNotEnoughChildren(WKTConstants::ABRIDGEDTRANSFORMATION);
+    }
+
+    auto &methodNode = abridgedNode->GP()->lookForChild(WKTConstants::METHOD);
+    if (isNull(methodNode)) {
+        ThrowMissing(WKTConstants::METHOD);
+    }
+    if (methodNode->GP()->childrenSize() == 0) {
+        ThrowNotEnoughChildren(WKTConstants::METHOD);
+    }
+
+    auto &sourceCRSNode = nodeP->lookForChild(WKTConstants::SOURCECRS);
+    const auto &sourceCRSNodeChildren = sourceCRSNode->GP()->children();
+    if (sourceCRSNodeChildren.size() != 1) {
+        ThrowNotEnoughChildren(WKTConstants::SOURCECRS);
+    }
+    auto sourceCRS = buildCRS(sourceCRSNodeChildren[0]);
+    if (!sourceCRS) {
+        throw ParsingException("Invalid content in SOURCECRS node");
+    }
+
+    auto &targetCRSNode = nodeP->lookForChild(WKTConstants::TARGETCRS);
+    const auto &targetCRSNodeChildren = targetCRSNode->GP()->children();
+    if (targetCRSNodeChildren.size() != 1) {
+        ThrowNotEnoughChildren(WKTConstants::TARGETCRS);
+    }
+    auto targetCRS = buildCRS(targetCRSNodeChildren[0]);
+    if (!targetCRS) {
+        throw ParsingException("Invalid content in TARGETCRS node");
+    }
+
+    std::vector<OperationParameterNNPtr> parameters;
+    std::vector<ParameterValueNNPtr> values;
+    auto defaultLinearUnit = UnitOfMeasure::NONE;
+    auto defaultAngularUnit = UnitOfMeasure::NONE;
+    consumeParameters(abridgedNode, true, parameters, values, defaultLinearUnit,
+                      defaultAngularUnit);
+
+    CRSPtr sourceTransformationCRS;
+    if (dynamic_cast<GeographicCRS *>(targetCRS.get())) {
+        sourceTransformationCRS = sourceCRS->extractGeographicCRS();
+        if (!sourceTransformationCRS) {
+            throw ParsingException("Cannot find GeographicCRS in sourceCRS");
+        }
+    } else {
+        sourceTransformationCRS = sourceCRS;
+    }
+
+    auto transformation = Transformation::create(
+        buildProperties(abridgedNode), NN_NO_CHECK(sourceTransformationCRS),
+        NN_NO_CHECK(targetCRS), nullptr, buildProperties(methodNode),
+        parameters, values, std::vector<PositionalAccuracyNNPtr>());
+
+    return BoundCRS::create(NN_NO_CHECK(sourceCRS), NN_NO_CHECK(targetCRS),
+                            transformation);
+}
+
+// ---------------------------------------------------------------------------
+
+TemporalCSNNPtr
+WKTParser::Private::buildTemporalCS(const WKTNodeNNPtr &parentNode) {
+
+    auto &csNode = parentNode->GP()->lookForChild(WKTConstants::CS);
+    if (isNull(csNode) &&
+        !ci_equal(parentNode->GP()->value(), WKTConstants::BASETIMECRS)) {
+        ThrowMissing(WKTConstants::CS);
+    }
+    auto cs = buildCS(csNode, parentNode, UnitOfMeasure::NONE);
+    auto temporalCS = nn_dynamic_pointer_cast<TemporalCS>(cs);
+    if (!temporalCS) {
+        ThrowNotExpectedCSType("temporal");
+    }
+    return NN_NO_CHECK(temporalCS);
+}
+
+// ---------------------------------------------------------------------------
+
+TemporalCRSNNPtr
+WKTParser::Private::buildTemporalCRS(const WKTNodeNNPtr &node) {
+    auto &datumNode =
+        node->GP()->lookForChild(WKTConstants::TDATUM, WKTConstants::TIMEDATUM);
+    if (isNull(datumNode)) {
+        throw ParsingException("Missing TDATUM / TIMEDATUM node");
+    }
+
+    return TemporalCRS::create(buildProperties(node),
+                               buildTemporalDatum(datumNode),
+                               buildTemporalCS(node));
+}
+
+// ---------------------------------------------------------------------------
+
+DerivedTemporalCRSNNPtr
+WKTParser::Private::buildDerivedTemporalCRS(const WKTNodeNNPtr &node) {
+    const auto *nodeP = node->GP();
+    auto &baseCRSNode = nodeP->lookForChild(WKTConstants::BASETIMECRS);
+    // given the constraints enforced on calling code path
+    assert(!isNull(baseCRSNode));
+
+    auto &derivingConversionNode =
+        nodeP->lookForChild(WKTConstants::DERIVINGCONVERSION);
+    if (isNull(derivingConversionNode)) {
+        ThrowNotEnoughChildren(WKTConstants::DERIVINGCONVERSION);
+    }
+
+    return DerivedTemporalCRS::create(
+        buildProperties(node), buildTemporalCRS(baseCRSNode),
+        buildConversion(derivingConversionNode, UnitOfMeasure::NONE,
+                        UnitOfMeasure::NONE),
+        buildTemporalCS(node));
+}
+
+// ---------------------------------------------------------------------------
+
+EngineeringCRSNNPtr
+WKTParser::Private::buildEngineeringCRS(const WKTNodeNNPtr &node) {
+    const auto *nodeP = node->GP();
+    auto &datumNode = nodeP->lookForChild(WKTConstants::EDATUM,
+                                          WKTConstants::ENGINEERINGDATUM);
+    if (isNull(datumNode)) {
+        throw ParsingException("Missing EDATUM / ENGINEERINGDATUM node");
+    }
+
+    auto &csNode = nodeP->lookForChild(WKTConstants::CS);
+    if (isNull(csNode) && !ci_equal(nodeP->value(), WKTConstants::BASEENGCRS)) {
+        ThrowMissing(WKTConstants::CS);
+    }
+
+    auto cs = buildCS(csNode, node, UnitOfMeasure::NONE);
+    return EngineeringCRS::create(buildProperties(node),
+                                  buildEngineeringDatum(datumNode), cs);
+}
+
+// ---------------------------------------------------------------------------
+
+EngineeringCRSNNPtr
+WKTParser::Private::buildEngineeringCRSFromLocalCS(const WKTNodeNNPtr &node) {
+    auto &datumNode = node->GP()->lookForChild(WKTConstants::LOCAL_DATUM);
+    auto cs = buildCS(null_node, node, UnitOfMeasure::NONE);
+    auto datum = EngineeringDatum::create(
+        !isNull(datumNode)
+            ? buildProperties(datumNode)
+            :
+            // In theory OGC 01-009 mandates LOCAL_DATUM, but GDAL has a
+            // tradition of emitting just LOCAL_CS["foo"]
+            emptyPropertyMap);
+    return EngineeringCRS::create(buildProperties(node), datum, cs);
+}
+
+// ---------------------------------------------------------------------------
+
+DerivedEngineeringCRSNNPtr
+WKTParser::Private::buildDerivedEngineeringCRS(const WKTNodeNNPtr &node) {
+    const auto *nodeP = node->GP();
+    auto &baseEngCRSNode = nodeP->lookForChild(WKTConstants::BASEENGCRS);
+    // given the constraints enforced on calling code path
+    assert(!isNull(baseEngCRSNode));
+
+    auto baseEngCRS = buildEngineeringCRS(baseEngCRSNode);
+
+    auto &derivingConversionNode =
+        nodeP->lookForChild(WKTConstants::DERIVINGCONVERSION);
+    if (isNull(derivingConversionNode)) {
+        ThrowNotEnoughChildren(WKTConstants::DERIVINGCONVERSION);
+    }
+    auto derivingConversion = buildConversion(
+        derivingConversionNode, UnitOfMeasure::NONE, UnitOfMeasure::NONE);
+
+    auto &csNode = nodeP->lookForChild(WKTConstants::CS);
+    if (isNull(csNode)) {
+        ThrowMissing(WKTConstants::CS);
+    }
+    auto cs = buildCS(csNode, node, UnitOfMeasure::NONE);
+
+    return DerivedEngineeringCRS::create(buildProperties(node), baseEngCRS,
+                                         derivingConversion, cs);
+}
+
+// ---------------------------------------------------------------------------
+
+ParametricCSNNPtr
+WKTParser::Private::buildParametricCS(const WKTNodeNNPtr &parentNode) {
+
+    auto &csNode = parentNode->GP()->lookForChild(WKTConstants::CS);
+    if (isNull(csNode) &&
+        !ci_equal(parentNode->GP()->value(), WKTConstants::BASEPARAMCRS)) {
+        ThrowMissing(WKTConstants::CS);
+    }
+    auto cs = buildCS(csNode, parentNode, UnitOfMeasure::NONE);
+    auto parametricCS = nn_dynamic_pointer_cast<ParametricCS>(cs);
+    if (!parametricCS) {
+        ThrowNotExpectedCSType("parametric");
+    }
+    return NN_NO_CHECK(parametricCS);
+}
+
+// ---------------------------------------------------------------------------
+
+ParametricCRSNNPtr
+WKTParser::Private::buildParametricCRS(const WKTNodeNNPtr &node) {
+    auto &datumNode = node->GP()->lookForChild(WKTConstants::PDATUM,
+                                               WKTConstants::PARAMETRICDATUM);
+    if (isNull(datumNode)) {
+        throw ParsingException("Missing PDATUM / PARAMETRICDATUM node");
+    }
+
+    return ParametricCRS::create(buildProperties(node),
+                                 buildParametricDatum(datumNode),
+                                 buildParametricCS(node));
+}
+
+// ---------------------------------------------------------------------------
+
+DerivedParametricCRSNNPtr
+WKTParser::Private::buildDerivedParametricCRS(const WKTNodeNNPtr &node) {
+    const auto *nodeP = node->GP();
+    auto &baseParamCRSNode = nodeP->lookForChild(WKTConstants::BASEPARAMCRS);
+    // given the constraints enforced on calling code path
+    assert(!isNull(baseParamCRSNode));
+
+    auto &derivingConversionNode =
+        nodeP->lookForChild(WKTConstants::DERIVINGCONVERSION);
+    if (isNull(derivingConversionNode)) {
+        ThrowNotEnoughChildren(WKTConstants::DERIVINGCONVERSION);
+    }
+
+    return DerivedParametricCRS::create(
+        buildProperties(node), buildParametricCRS(baseParamCRSNode),
+        buildConversion(derivingConversionNode, UnitOfMeasure::NONE,
+                        UnitOfMeasure::NONE),
+        buildParametricCS(node));
+}
+
+// ---------------------------------------------------------------------------
+
+DerivedProjectedCRSNNPtr
+WKTParser::Private::buildDerivedProjectedCRS(const WKTNodeNNPtr &node) {
+    const auto *nodeP = node->GP();
+    auto &baseProjCRSNode = nodeP->lookForChild(WKTConstants::BASEPROJCRS);
+    if (isNull(baseProjCRSNode)) {
+        ThrowNotEnoughChildren(WKTConstants::BASEPROJCRS);
+    }
+    auto baseProjCRS = buildProjectedCRS(baseProjCRSNode);
+
+    auto &conversionNode =
+        nodeP->lookForChild(WKTConstants::DERIVINGCONVERSION);
+    if (isNull(conversionNode)) {
+        ThrowNotEnoughChildren(WKTConstants::DERIVINGCONVERSION);
+    }
+
+    auto linearUnit = buildUnitInSubNode(node);
+    auto angularUnit =
+        baseProjCRS->baseCRS()->coordinateSystem()->axisList()[0]->unit();
+
+    auto conversion = buildConversion(conversionNode, linearUnit, angularUnit);
+
+    auto &csNode = nodeP->lookForChild(WKTConstants::CS);
+    if (isNull(csNode) && !ci_equal(nodeP->value(), WKTConstants::PROJCS)) {
+        ThrowMissing(WKTConstants::CS);
+    }
+    auto cs = buildCS(csNode, node, UnitOfMeasure::NONE);
+    return DerivedProjectedCRS::create(buildProperties(node), baseProjCRS,
+                                       conversion, cs);
+}
+
+// ---------------------------------------------------------------------------
+
+static bool isGeodeticCRS(const std::string &name) {
+    return ci_equal(name, WKTConstants::GEODCRS) ||       // WKT2
+           ci_equal(name, WKTConstants::GEODETICCRS) ||   // WKT2
+           ci_equal(name, WKTConstants::GEOGCRS) ||       // WKT2 2018
+           ci_equal(name, WKTConstants::GEOGRAPHICCRS) || // WKT2 2018
+           ci_equal(name, WKTConstants::GEOGCS) ||        // WKT1
+           ci_equal(name, WKTConstants::GEOCCS);          // WKT1
+}
+
+// ---------------------------------------------------------------------------
+
+CRSPtr WKTParser::Private::buildCRS(const WKTNodeNNPtr &node) {
+    const auto *nodeP = node->GP();
+    const std::string &name(nodeP->value());
+
+    if (isGeodeticCRS(name)) {
+        if (!isNull(nodeP->lookForChild(WKTConstants::BASEGEOGCRS,
+                                        WKTConstants::BASEGEODCRS))) {
+            return buildDerivedGeodeticCRS(node);
+        } else {
+            return util::nn_static_pointer_cast<CRS>(buildGeodeticCRS(node));
+        }
+    }
+
+    if (ci_equal(name, WKTConstants::PROJCS) ||
+        ci_equal(name, WKTConstants::PROJCRS) ||
+        ci_equal(name, WKTConstants::PROJECTEDCRS)) {
+        return util::nn_static_pointer_cast<CRS>(buildProjectedCRS(node));
+    }
+
+    if (ci_equal(name, WKTConstants::VERT_CS) ||
+        ci_equal(name, WKTConstants::VERTCRS) ||
+        ci_equal(name, WKTConstants::VERTICALCRS)) {
+        if (!isNull(nodeP->lookForChild(WKTConstants::BASEVERTCRS))) {
+            return util::nn_static_pointer_cast<CRS>(
+                buildDerivedVerticalCRS(node));
+        } else {
+            return util::nn_static_pointer_cast<CRS>(buildVerticalCRS(node));
+        }
+    }
+
+    if (ci_equal(name, WKTConstants::COMPD_CS) ||
+        ci_equal(name, WKTConstants::COMPOUNDCRS)) {
+        return util::nn_static_pointer_cast<CRS>(buildCompoundCRS(node));
+    }
+
+    if (ci_equal(name, WKTConstants::BOUNDCRS)) {
+        return util::nn_static_pointer_cast<CRS>(buildBoundCRS(node));
+    }
+
+    if (ci_equal(name, WKTConstants::TIMECRS)) {
+        if (!isNull(nodeP->lookForChild(WKTConstants::BASETIMECRS))) {
+            return util::nn_static_pointer_cast<CRS>(
+                buildDerivedTemporalCRS(node));
+        } else {
+            return util::nn_static_pointer_cast<CRS>(buildTemporalCRS(node));
+        }
+    }
+
+    if (ci_equal(name, WKTConstants::DERIVEDPROJCRS)) {
+        return util::nn_static_pointer_cast<CRS>(
+            buildDerivedProjectedCRS(node));
+    }
+
+    if (ci_equal(name, WKTConstants::ENGCRS) ||
+        ci_equal(name, WKTConstants::ENGINEERINGCRS)) {
+        if (!isNull(nodeP->lookForChild(WKTConstants::BASEENGCRS))) {
+            return util::nn_static_pointer_cast<CRS>(
+                buildDerivedEngineeringCRS(node));
+        } else {
+            return util::nn_static_pointer_cast<CRS>(buildEngineeringCRS(node));
+        }
+    }
+
+    if (ci_equal(name, WKTConstants::LOCAL_CS)) {
+        return util::nn_static_pointer_cast<CRS>(
+            buildEngineeringCRSFromLocalCS(node));
+    }
+
+    if (ci_equal(name, WKTConstants::PARAMETRICCRS)) {
+        if (!isNull(nodeP->lookForChild(WKTConstants::BASEPARAMCRS))) {
+            return util::nn_static_pointer_cast<CRS>(
+                buildDerivedParametricCRS(node));
+        } else {
+            return util::nn_static_pointer_cast<CRS>(buildParametricCRS(node));
+        }
+    }
+
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+BaseObjectNNPtr WKTParser::Private::build(const WKTNodeNNPtr &node) {
+    const auto *nodeP = node->GP();
+    const std::string &name(nodeP->value());
+
+    auto crs = buildCRS(node);
+    if (crs) {
+        if (!toWGS84Parameters_.empty()) {
+            return util::nn_static_pointer_cast<BaseObject>(
+                BoundCRS::createFromTOWGS84(NN_NO_CHECK(crs),
+                                            toWGS84Parameters_));
+        }
+        if (!datumPROJ4Grids_.empty()) {
+            return util::nn_static_pointer_cast<BaseObject>(
+                BoundCRS::createFromNadgrids(NN_NO_CHECK(crs),
+                                             datumPROJ4Grids_));
+        }
+        return util::nn_static_pointer_cast<BaseObject>(NN_NO_CHECK(crs));
+    }
+
+    if (ci_equal(name, WKTConstants::DATUM) ||
+        ci_equal(name, WKTConstants::GEODETICDATUM) ||
+        ci_equal(name, WKTConstants::TRF)) {
+        return util::nn_static_pointer_cast<BaseObject>(
+            buildGeodeticReferenceFrame(node, PrimeMeridian::GREENWICH,
+                                        null_node));
+    }
+
+    if (ci_equal(name, WKTConstants::ENSEMBLE)) {
+        return util::nn_static_pointer_cast<BaseObject>(buildDatumEnsemble(
+            node, PrimeMeridian::GREENWICH,
+            !isNull(nodeP->lookForChild(WKTConstants::ELLIPSOID))));
+    }
+
+    if (ci_equal(name, WKTConstants::VDATUM) ||
+        ci_equal(name, WKTConstants::VERT_DATUM) ||
+        ci_equal(name, WKTConstants::VERTICALDATUM) ||
+        ci_equal(name, WKTConstants::VRF)) {
+        return util::nn_static_pointer_cast<BaseObject>(
+            buildVerticalReferenceFrame(node, null_node));
+    }
+
+    if (ci_equal(name, WKTConstants::TDATUM) ||
+        ci_equal(name, WKTConstants::TIMEDATUM)) {
+        return util::nn_static_pointer_cast<BaseObject>(
+            buildTemporalDatum(node));
+    }
+
+    if (ci_equal(name, WKTConstants::EDATUM) ||
+        ci_equal(name, WKTConstants::ENGINEERINGDATUM)) {
+        return util::nn_static_pointer_cast<BaseObject>(
+            buildEngineeringDatum(node));
+    }
+
+    if (ci_equal(name, WKTConstants::PDATUM) ||
+        ci_equal(name, WKTConstants::PARAMETRICDATUM)) {
+        return util::nn_static_pointer_cast<BaseObject>(
+            buildParametricDatum(node));
+    }
+
+    if (ci_equal(name, WKTConstants::ELLIPSOID) ||
+        ci_equal(name, WKTConstants::SPHEROID)) {
+        return util::nn_static_pointer_cast<BaseObject>(buildEllipsoid(node));
+    }
+
+    if (ci_equal(name, WKTConstants::COORDINATEOPERATION)) {
+        return util::nn_static_pointer_cast<BaseObject>(
+            buildCoordinateOperation(node));
+    }
+
+    if (ci_equal(name, WKTConstants::CONVERSION)) {
+        return util::nn_static_pointer_cast<BaseObject>(
+            buildConversion(node, UnitOfMeasure::METRE, UnitOfMeasure::DEGREE));
+    }
+
+    if (ci_equal(name, WKTConstants::CONCATENATEDOPERATION)) {
+        return util::nn_static_pointer_cast<BaseObject>(
+            buildConcatenatedOperation(node));
+    }
+
+    if (ci_equal(name, WKTConstants::ID) ||
+        ci_equal(name, WKTConstants::AUTHORITY)) {
+        return util::nn_static_pointer_cast<BaseObject>(
+            NN_NO_CHECK(buildId(node, false)));
+    }
+
+    throw ParsingException(concat("unhandled keyword: ", name));
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a sub-class of BaseObject from a user specified text.
+ *
+ * The text can be a:
+ * <ul>
+ * <li>WKT string</li>
+ * <li>PROJ string</li>
+ * <li>database code, prefixed by its authoriy. e.g. "EPSG:4326"</li>
+ * <li>URN. e.g. "urn:ogc:def:crs:EPSG::4326",
+ *     "urn:ogc:def:coordinateOperation:EPSG::1671"</li>
+ * <li>an objet name. e.g "WGS 84", "WGS 84 / UTM zone 31N". In that case as
+ *     uniqueness is not guaranteed, the function may apply heuristics to
+ *     determine the appropriate best match.</li>
+ * </ul>
+ *
+ * @param text One of the above mentionned text format
+ * @param dbContext Database context, or nullptr (in which case database
+ * lookups will not work)
+ * @param usePROJ4InitRules When set to true,
+ * init=epsg:XXXX syntax will be allowed and will be interpreted according to
+ * PROJ.4 and PROJ.5 rules, that is geodeticCRS will have longitude, latitude
+ * order and will expect/output coordinates in radians. ProjectedCRS will have
+ * easting, northing axis order (except the ones with Transverse Mercator South
+ * Orientated projection). In that mode, the epsg:XXXX syntax will be also
+ * interprated the same way.
+ * @throw ParsingException
+ */
+BaseObjectNNPtr createFromUserInput(const std::string &text,
+                                    const DatabaseContextPtr &dbContext,
+                                    bool usePROJ4InitRules) {
+
+    for (const auto &wktConstants : WKTConstants::constants()) {
+        if (ci_starts_with(text, wktConstants)) {
+            return WKTParser()
+                .attachDatabaseContext(dbContext)
+                .setStrict(false)
+                .createFromWKT(text);
+        }
+    }
+    const char *textWithoutPlusPrefix = text.c_str();
+    if (textWithoutPlusPrefix[0] == '+')
+        textWithoutPlusPrefix++;
+
+    if (strncmp(textWithoutPlusPrefix, "proj=", strlen("proj=")) == 0 ||
+        strncmp(textWithoutPlusPrefix, "init=", strlen("init=")) == 0 ||
+        strncmp(textWithoutPlusPrefix, "title=", strlen("title=")) == 0) {
+        return PROJStringParser()
+            .attachDatabaseContext(dbContext)
+            .setUsePROJ4InitRules(usePROJ4InitRules)
+            .createFromPROJString(text);
+    }
+
+    auto tokens = split(text, ':');
+    if (tokens.size() == 2) {
+        if (!dbContext) {
+            throw ParsingException("no database context specified");
+        }
+        DatabaseContextNNPtr dbContextNNPtr(NN_NO_CHECK(dbContext));
+        const auto &authName = tokens[0];
+        const auto &code = tokens[1];
+        auto factory = AuthorityFactory::create(dbContextNNPtr, authName);
+        try {
+            return factory->createCoordinateReferenceSystem(code);
+        } catch (...) {
+            const auto authorities = dbContextNNPtr->getAuthorities();
+            for (const auto &authCandidate : authorities) {
+                if (ci_equal(authCandidate, authName)) {
+                    return AuthorityFactory::create(dbContextNNPtr,
+                                                    authCandidate)
+                        ->createCoordinateReferenceSystem(code);
+                }
+            }
+            throw;
+        }
+    }
+
+    // urn:ogc:def:crs:EPSG::4326
+    if (tokens.size() == 7) {
+        if (!dbContext) {
+            throw ParsingException("no database context specified");
+        }
+        const auto &type = tokens[3];
+        auto factory =
+            AuthorityFactory::create(NN_NO_CHECK(dbContext), tokens[4]);
+        const auto &code = tokens[6];
+        if (type == "crs") {
+            return factory->createCoordinateReferenceSystem(code);
+        }
+        if (type == "coordinateOperation") {
+            return factory->createCoordinateOperation(code, true);
+        }
+        if (type == "datum") {
+            return factory->createDatum(code);
+        }
+        if (type == "ellipsoid") {
+            return factory->createEllipsoid(code);
+        }
+        if (type == "meridian") {
+            return factory->createPrimeMeridian(code);
+        }
+        throw ParsingException(concat("unhandled object type: ", type));
+    }
+
+    if (dbContext) {
+        auto factory =
+            AuthorityFactory::create(NN_NO_CHECK(dbContext), std::string());
+        // First pass: exact match on CRS objects
+        // Second pass: exact match on other objects
+        // Third pass: approximate match on CRS objects
+        // Fourth pass: approximate match on other objects
+        constexpr size_t limitResultCount = 10;
+        for (int pass = 0; pass <= 3; ++pass) {
+            const bool approximateMatch = (pass >= 2);
+            auto res = factory->createObjectsFromName(
+                text,
+                (pass == 0 || pass == 2)
+                    ? std::vector<
+                          AuthorityFactory::ObjectType>{AuthorityFactory::
+                                                            ObjectType::CRS}
+                    : std::vector<
+                          AuthorityFactory::
+                              ObjectType>{AuthorityFactory::ObjectType::
+                                              ELLIPSOID,
+                                          AuthorityFactory::ObjectType::DATUM,
+                                          AuthorityFactory::ObjectType::
+                                              COORDINATE_OPERATION},
+                approximateMatch, limitResultCount);
+            if (res.size() == 1) {
+                return res.front();
+            }
+            if (res.size() > 1) {
+                if (pass == 0 || pass == 2) {
+                    for (size_t ndim = 2; ndim <= 3; ndim++) {
+                        for (const auto &obj : res) {
+                            auto crs =
+                                dynamic_cast<crs::GeographicCRS *>(obj.get());
+                            if (crs &&
+                                crs->coordinateSystem()->axisList().size() ==
+                                    ndim) {
+                                return obj;
+                            }
+                        }
+                    }
+                }
+
+                std::string msg("several objects matching this name: ");
+                bool first = true;
+                for (const auto &obj : res) {
+                    if (msg.size() > 200) {
+                        msg += ", ...";
+                        break;
+                    }
+                    if (!first) {
+                        msg += ", ";
+                    }
+                    first = false;
+                    msg += obj->nameStr();
+                }
+                throw ParsingException(msg);
+            }
+        }
+    }
+
+    throw ParsingException("unrecognized format / unknown name");
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a sub-class of BaseObject from a WKT string.
+ *
+ * By default, validation is strict (to the extent of the checks that are
+ * actually implemented. Currently only WKT1 strict grammar is checked), and
+ * any issue detected will cause an exception to be thrown, unless
+ * setStrict(false) is called priorly.
+ *
+ * In non-strict mode, non-fatal issues will be recovered and simply listed
+ * in warningList(). This does not prevent more severe errors to cause an
+ * exception to be thrown.
+ *
+ * @throw ParsingException
+ */
+BaseObjectNNPtr WKTParser::createFromWKT(const std::string &wkt) {
+    WKTNodeNNPtr root = WKTNode::createFrom(wkt);
+    auto obj = d->build(root);
+
+    const auto dialect = guessDialect(wkt);
+    if (dialect == WKTGuessedDialect::WKT1_GDAL ||
+        dialect == WKTGuessedDialect::WKT1_ESRI) {
+        auto errorMsg = pj_wkt1_parse(wkt);
+        if (!errorMsg.empty()) {
+            d->emitRecoverableAssertion(errorMsg);
+        }
+    } else if (dialect == WKTGuessedDialect::WKT2_2015 ||
+               dialect == WKTGuessedDialect::WKT2_2018) {
+        auto errorMsg = pj_wkt2_parse(wkt);
+        if (!errorMsg.empty()) {
+            d->emitRecoverableAssertion(errorMsg);
+        }
+    }
+
+    return obj;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Attach a database context, to allow queries in it if needed.
+ */
+WKTParser &
+WKTParser::attachDatabaseContext(const DatabaseContextPtr &dbContext) {
+    d->dbContext_ = dbContext;
+    return *this;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Guess the "dialect" of the WKT string.
+ */
+WKTParser::WKTGuessedDialect
+WKTParser::guessDialect(const std::string &wkt) noexcept {
+    const std::string *const wkt1_keywords[] = {
+        &WKTConstants::GEOCCS, &WKTConstants::GEOGCS,  &WKTConstants::COMPD_CS,
+        &WKTConstants::PROJCS, &WKTConstants::VERT_CS, &WKTConstants::LOCAL_CS};
+    for (const auto &pointerKeyword : wkt1_keywords) {
+        if (ci_starts_with(wkt, *pointerKeyword)) {
+
+            if (ci_find(wkt, "GEOGCS[\"GCS_") != std::string::npos) {
+                return WKTGuessedDialect::WKT1_ESRI;
+            }
+
+            return WKTGuessedDialect::WKT1_GDAL;
+        }
+    }
+
+    const std::string *const wkt2_2018_only_keywords[] = {
+        &WKTConstants::GEOGCRS,
+        // contained in previous one
+        // &WKTConstants::BASEGEOGCRS,
+        &WKTConstants::CONCATENATEDOPERATION, &WKTConstants::USAGE,
+        &WKTConstants::DYNAMIC, &WKTConstants::FRAMEEPOCH, &WKTConstants::MODEL,
+        &WKTConstants::VELOCITYGRID, &WKTConstants::ENSEMBLE,
+        &WKTConstants::DERIVEDPROJCRS, &WKTConstants::BASEPROJCRS,
+        &WKTConstants::GEOGRAPHICCRS, &WKTConstants::TRF, &WKTConstants::VRF};
+
+    for (const auto &pointerKeyword : wkt2_2018_only_keywords) {
+        auto pos = ci_find(wkt, *pointerKeyword);
+        if (pos != std::string::npos &&
+            wkt[pos + pointerKeyword->size()] == '[') {
+            return WKTGuessedDialect::WKT2_2018;
+        }
+    }
+    static const char *const wkt2_2018_only_substrings[] = {
+        "CS[TemporalDateTime,", "CS[TemporalCount,", "CS[TemporalMeasure,",
+    };
+    for (const auto &substrings : wkt2_2018_only_substrings) {
+        if (ci_find(wkt, substrings) != std::string::npos) {
+            return WKTGuessedDialect::WKT2_2018;
+        }
+    }
+
+    for (const auto &wktConstants : WKTConstants::constants()) {
+        if (ci_starts_with(wkt, wktConstants)) {
+            return WKTGuessedDialect::WKT2_2015;
+        }
+    }
+
+    return WKTGuessedDialect::NOT_WKT;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+FormattingException::FormattingException(const char *message)
+    : Exception(message) {}
+
+// ---------------------------------------------------------------------------
+
+FormattingException::FormattingException(const std::string &message)
+    : Exception(message) {}
+
+// ---------------------------------------------------------------------------
+
+FormattingException::FormattingException(const FormattingException &) = default;
+
+// ---------------------------------------------------------------------------
+
+FormattingException::~FormattingException() = default;
+
+// ---------------------------------------------------------------------------
+
+void FormattingException::Throw(const char *msg) {
+    throw FormattingException(msg);
+}
+
+// ---------------------------------------------------------------------------
+
+void FormattingException::Throw(const std::string &msg) {
+    throw FormattingException(msg);
+}
+
+// ---------------------------------------------------------------------------
+
+ParsingException::ParsingException(const char *message) : Exception(message) {}
+
+// ---------------------------------------------------------------------------
+
+ParsingException::ParsingException(const std::string &message)
+    : Exception(message) {}
+
+// ---------------------------------------------------------------------------
+
+ParsingException::ParsingException(const ParsingException &) = default;
+
+// ---------------------------------------------------------------------------
+
+ParsingException::~ParsingException() = default;
+
+// ---------------------------------------------------------------------------
+
+IPROJStringExportable::~IPROJStringExportable() = default;
+
+// ---------------------------------------------------------------------------
+
+std::string IPROJStringExportable::exportToPROJString(
+    PROJStringFormatter *formatter) const {
+    _exportToPROJString(formatter);
+    if (formatter->getAddNoDefs() &&
+        formatter->convention() ==
+            io::PROJStringFormatter::Convention::PROJ_4 &&
+        dynamic_cast<const crs::CRS *>(this)) {
+        if (!formatter->hasParam("no_defs")) {
+            formatter->addParam("no_defs");
+        }
+    }
+    return formatter->toString();
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+struct Step {
+    std::string name{};
+    bool isInit = false;
+    bool inverted{false};
+
+    struct KeyValue {
+        std::string key{};
+        std::string value{};
+
+        explicit KeyValue(const std::string &keyIn) : key(keyIn) {}
+
+        KeyValue(const char *keyIn, const std::string &valueIn);
+
+        KeyValue(const std::string &keyIn, const std::string &valueIn)
+            : key(keyIn), value(valueIn) {}
+
+        // cppcheck-suppress functionStatic
+        bool keyEquals(const char *otherKey) const noexcept {
+            return key == otherKey;
+        }
+
+        // cppcheck-suppress functionStatic
+        bool equals(const char *otherKey, const char *otherVal) const noexcept {
+            return key == otherKey && value == otherVal;
+        }
+
+        bool operator!=(const KeyValue &other) const noexcept {
+            return key != other.key || value != other.value;
+        }
+    };
+
+    std::vector<KeyValue> paramValues{};
+};
+
+Step::KeyValue::KeyValue(const char *keyIn, const std::string &valueIn)
+    : key(keyIn), value(valueIn) {}
+
+struct PROJStringFormatter::Private {
+    PROJStringFormatter::Convention convention_ =
+        PROJStringFormatter::Convention::PROJ_5;
+    std::vector<double> toWGS84Parameters_{};
+    std::string vDatumExtension_{};
+    std::string hDatumExtension_{};
+
+    std::list<Step> steps_{};
+    std::vector<Step::KeyValue> globalParamValues_{};
+
+    struct InversionStackElt {
+        std::list<Step>::iterator startIter{};
+        bool iterValid = false;
+        bool currentInversionState = false;
+    };
+    std::vector<InversionStackElt> inversionStack_{InversionStackElt()};
+    bool omitProjLongLatIfPossible_ = false;
+    bool omitZUnitConversion_ = false;
+    DatabaseContextPtr dbContext_{};
+    bool useETMercForTMerc_ = false;
+    bool useETMercForTMercSet_ = false;
+    bool addNoDefs_ = true;
+    bool coordOperationOptimizations_ = false;
+
+    std::string result_{};
+
+    // cppcheck-suppress functionStatic
+    void appendToResult(const char *str);
+
+    // cppcheck-suppress functionStatic
+    void addStep();
+};
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+PROJStringFormatter::PROJStringFormatter(Convention conventionIn,
+                                         const DatabaseContextPtr &dbContext)
+    : d(internal::make_unique<Private>()) {
+    d->convention_ = conventionIn;
+    d->dbContext_ = dbContext;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+PROJStringFormatter::~PROJStringFormatter() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Constructs a new formatter.
+ *
+ * A formatter can be used only once (its internal state is mutated)
+ *
+ * Its default behaviour can be adjusted with the different setters.
+ *
+ * @param conventionIn PROJ string flavor. Defaults to Convention::PROJ_5
+ * @param dbContext Database context (can help to find alternative grid names).
+ * May be nullptr
+ * @return new formatter.
+ */
+PROJStringFormatterNNPtr
+PROJStringFormatter::create(Convention conventionIn,
+                            DatabaseContextPtr dbContext) {
+    return NN_NO_CHECK(PROJStringFormatter::make_unique<PROJStringFormatter>(
+        conventionIn, dbContext));
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Set whether Extented Transverse Mercator (etmerc) should be used
+ * instead of tmerc */
+void PROJStringFormatter::setUseETMercForTMerc(bool flag) {
+    d->useETMercForTMerc_ = flag;
+    d->useETMercForTMercSet_ = true;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns the PROJ string. */
+const std::string &PROJStringFormatter::toString() const {
+
+    assert(d->inversionStack_.size() == 1);
+
+    d->result_.clear();
+
+    for (auto iter = d->steps_.begin(); iter != d->steps_.end();) {
+        // Remove no-op helmert
+        auto &step = *iter;
+        const auto paramCount = step.paramValues.size();
+        if (step.name == "helmert" && (paramCount == 3 || paramCount == 8) &&
+            step.paramValues[0].equals("x", "0") &&
+            step.paramValues[1].equals("y", "0") &&
+            step.paramValues[2].equals("z", "0") &&
+            (paramCount == 3 ||
+             (step.paramValues[3].equals("rx", "0") &&
+              step.paramValues[4].equals("ry", "0") &&
+              step.paramValues[5].equals("rz", "0") &&
+              step.paramValues[6].equals("s", "0") &&
+              step.paramValues[7].keyEquals("convention")))) {
+            iter = d->steps_.erase(iter);
+        } else if (d->coordOperationOptimizations_ &&
+                   step.name == "unitconvert" && paramCount == 2 &&
+                   step.paramValues[0].keyEquals("xy_in") &&
+                   step.paramValues[1].keyEquals("xy_out") &&
+                   step.paramValues[0].value == step.paramValues[1].value) {
+            iter = d->steps_.erase(iter);
+        } else {
+            ++iter;
+        }
+    }
+
+    for (auto &step : d->steps_) {
+        if (!step.inverted) {
+            continue;
+        }
+
+        const auto paramCount = step.paramValues.size();
+
+        // axisswap order=2,1 is its own inverse
+        if (step.name == "axisswap" && paramCount == 1 &&
+            step.paramValues[0].equals("order", "2,1")) {
+            step.inverted = false;
+            continue;
+        }
+
+        // handle unitconvert inverse
+        if (step.name == "unitconvert" && paramCount == 2 &&
+            step.paramValues[0].keyEquals("xy_in") &&
+            step.paramValues[1].keyEquals("xy_out")) {
+            std::swap(step.paramValues[0].value, step.paramValues[1].value);
+            step.inverted = false;
+            continue;
+        }
+
+        if (step.name == "unitconvert" && paramCount == 2 &&
+            step.paramValues[0].keyEquals("z_in") &&
+            step.paramValues[1].keyEquals("z_out")) {
+            std::swap(step.paramValues[0].value, step.paramValues[1].value);
+            step.inverted = false;
+            continue;
+        }
+
+        if (step.name == "unitconvert" && paramCount == 4 &&
+            step.paramValues[0].keyEquals("xy_in") &&
+            step.paramValues[1].keyEquals("z_in") &&
+            step.paramValues[2].keyEquals("xy_out") &&
+            step.paramValues[3].keyEquals("z_out")) {
+            std::swap(step.paramValues[0].value, step.paramValues[2].value);
+            std::swap(step.paramValues[1].value, step.paramValues[3].value);
+            step.inverted = false;
+            continue;
+        }
+    }
+
+    bool changeDone;
+    do {
+        changeDone = false;
+        auto iterPrev = d->steps_.begin();
+        if (iterPrev == d->steps_.end()) {
+            break;
+        }
+        auto iterCur = iterPrev;
+        iterCur++;
+        for (size_t i = 1; i < d->steps_.size(); ++i, ++iterCur, ++iterPrev) {
+
+            auto &prevStep = *iterPrev;
+            auto &curStep = *iterCur;
+
+            const auto curStepParamCount = curStep.paramValues.size();
+            const auto prevStepParamCount = prevStep.paramValues.size();
+
+            // longlat (or its inverse) with ellipsoid only is a no-op
+            // do that only for an internal step
+            if (i + 1 < d->steps_.size() && curStep.name == "longlat" &&
+                curStepParamCount == 1 &&
+                curStep.paramValues[0].keyEquals("ellps")) {
+                d->steps_.erase(iterCur);
+                changeDone = true;
+                break;
+            }
+
+            // unitconvert (xy) followed by its inverse is a no-op
+            if (curStep.name == "unitconvert" &&
+                prevStep.name == "unitconvert" && !curStep.inverted &&
+                !prevStep.inverted && curStepParamCount == 2 &&
+                prevStepParamCount == 2 &&
+                curStep.paramValues[0].keyEquals("xy_in") &&
+                prevStep.paramValues[0].keyEquals("xy_in") &&
+                curStep.paramValues[1].keyEquals("xy_out") &&
+                prevStep.paramValues[1].keyEquals("xy_out") &&
+                curStep.paramValues[0].value == prevStep.paramValues[1].value &&
+                curStep.paramValues[1].value == prevStep.paramValues[0].value) {
+                ++iterCur;
+                d->steps_.erase(iterPrev, iterCur);
+                changeDone = true;
+                break;
+            }
+
+            // unitconvert (z) followed by its inverse is a no-op
+            if (curStep.name == "unitconvert" &&
+                prevStep.name == "unitconvert" && !curStep.inverted &&
+                !prevStep.inverted && curStepParamCount == 2 &&
+                prevStepParamCount == 2 &&
+                curStep.paramValues[0].keyEquals("z_in") &&
+                prevStep.paramValues[0].keyEquals("z_in") &&
+                curStep.paramValues[1].keyEquals("z_out") &&
+                prevStep.paramValues[1].keyEquals("z_out") &&
+                curStep.paramValues[0].value == prevStep.paramValues[1].value &&
+                curStep.paramValues[1].value == prevStep.paramValues[0].value) {
+                ++iterCur;
+                d->steps_.erase(iterPrev, iterCur);
+                changeDone = true;
+                break;
+            }
+
+            // unitconvert (xyz) followed by its inverse is a no-op
+            if (curStep.name == "unitconvert" &&
+                prevStep.name == "unitconvert" && !curStep.inverted &&
+                !prevStep.inverted && curStepParamCount == 4 &&
+                prevStepParamCount == 4 &&
+                curStep.paramValues[0].keyEquals("xy_in") &&
+                prevStep.paramValues[0].keyEquals("xy_in") &&
+                curStep.paramValues[1].keyEquals("z_in") &&
+                prevStep.paramValues[1].keyEquals("z_in") &&
+                curStep.paramValues[2].keyEquals("xy_out") &&
+                prevStep.paramValues[2].keyEquals("xy_out") &&
+                curStep.paramValues[3].keyEquals("z_out") &&
+                prevStep.paramValues[3].keyEquals("z_out") &&
+                curStep.paramValues[0].value == prevStep.paramValues[2].value &&
+                curStep.paramValues[1].value == prevStep.paramValues[3].value &&
+                curStep.paramValues[2].value == prevStep.paramValues[0].value &&
+                curStep.paramValues[3].value == prevStep.paramValues[1].value) {
+                ++iterCur;
+                d->steps_.erase(iterPrev, iterCur);
+                changeDone = true;
+                break;
+            }
+
+            // combine unitconvert (xy) and unitconvert (z)
+            for (int k = 0; k < 2; ++k) {
+                auto &first = (k == 0) ? curStep : prevStep;
+                auto &second = (k == 0) ? prevStep : curStep;
+                if (first.name == "unitconvert" &&
+                    second.name == "unitconvert" && !first.inverted &&
+                    !second.inverted && first.paramValues.size() == 2 &&
+                    second.paramValues.size() == 2 &&
+                    second.paramValues[0].keyEquals("xy_in") &&
+                    second.paramValues[1].keyEquals("xy_out") &&
+                    first.paramValues[0].keyEquals("z_in") &&
+                    first.paramValues[1].keyEquals("z_out")) {
+
+                    auto xy_in = second.paramValues[0].value;
+                    auto xy_out = second.paramValues[1].value;
+                    auto z_in = first.paramValues[0].value;
+                    auto z_out = first.paramValues[1].value;
+                    d->steps_.erase(iterPrev, iterCur);
+                    iterCur->paramValues.clear();
+                    iterCur->paramValues.emplace_back(
+                        Step::KeyValue("xy_in", xy_in));
+                    iterCur->paramValues.emplace_back(
+                        Step::KeyValue("z_in", z_in));
+                    iterCur->paramValues.emplace_back(
+                        Step::KeyValue("xy_out", xy_out));
+                    iterCur->paramValues.emplace_back(
+                        Step::KeyValue("z_out", z_out));
+                    changeDone = true;
+                    break;
+                }
+            }
+            if (changeDone) {
+                break;
+            }
+
+            // +step +proj=unitconvert +xy_in=X1 +xy_out=X2
+            //  +step +proj=unitconvert +xy_in=X2 +z_in=Z1 +xy_out=X1 +z_out=Z2
+            // ==> step +proj=unitconvert +z_in=Z1 +z_out=Z2
+            for (int k = 0; k < 2; ++k) {
+                auto &first = (k == 0) ? curStep : prevStep;
+                auto &second = (k == 0) ? prevStep : curStep;
+                if (first.name == "unitconvert" &&
+                    second.name == "unitconvert" && !first.inverted &&
+                    !second.inverted && first.paramValues.size() == 4 &&
+                    second.paramValues.size() == 2 &&
+                    first.paramValues[0].keyEquals("xy_in") &&
+                    first.paramValues[1].keyEquals("z_in") &&
+                    first.paramValues[2].keyEquals("xy_out") &&
+                    first.paramValues[3].keyEquals("z_out") &&
+                    second.paramValues[0].keyEquals("xy_in=") &&
+                    second.paramValues[1].keyEquals("xy_out") &&
+                    first.paramValues[0].value == second.paramValues[1].value &&
+                    first.paramValues[2].value == second.paramValues[0].value) {
+                    auto z_in = first.paramValues[1].value;
+                    auto z_out = first.paramValues[3].value;
+                    if (z_in != z_out) {
+                        d->steps_.erase(iterPrev, iterCur);
+                        iterCur->paramValues.clear();
+                        iterCur->paramValues.emplace_back(
+                            Step::KeyValue("z_in", z_in));
+                        iterCur->paramValues.emplace_back(
+                            Step::KeyValue("z_out", z_out));
+                    } else {
+                        ++iterCur;
+                        d->steps_.erase(iterPrev, iterCur);
+                    }
+                    changeDone = true;
+                    break;
+                }
+            }
+            if (changeDone) {
+                break;
+            }
+
+            // axisswap order=2,1 followed by itself is a no-op
+            if (curStep.name == "axisswap" && prevStep.name == "axisswap" &&
+                curStepParamCount == 1 && prevStepParamCount == 1 &&
+                curStep.paramValues[0].equals("order", "2,1") &&
+                prevStep.paramValues[0].equals("order", "2,1")) {
+                ++iterCur;
+                d->steps_.erase(iterPrev, iterCur);
+                changeDone = true;
+                break;
+            }
+
+            // axisswap order=2,1, unitconvert, axisswap order=2,1 -> can
+            // suppress axisswap
+            if (i + 1 < d->steps_.size() && prevStep.name == "axisswap" &&
+                curStep.name == "unitconvert" && prevStepParamCount == 1 &&
+                prevStep.paramValues[0].equals("order", "2,1")) {
+                auto iterNext = iterCur;
+                ++iterNext;
+                auto &nextStep = *iterNext;
+                if (nextStep.name == "axisswap" &&
+                    nextStep.paramValues.size() == 1 &&
+                    nextStep.paramValues[0].equals("order", "2,1")) {
+                    d->steps_.erase(iterPrev);
+                    d->steps_.erase(iterNext);
+                    changeDone = true;
+                    break;
+                }
+            }
+
+            // for practical purposes WGS84 and GRS80 ellipsoids are
+            // equivalents (cartesian transform between both lead to differences
+            // of the order of 1e-14 deg..).
+            // No need to do a cart roundtrip for that...
+            // and actually IGNF uses the GRS80 definition for the WGS84 datum
+            if (curStep.name == "cart" && prevStep.name == "cart" &&
+                curStep.inverted == !prevStep.inverted &&
+                curStepParamCount == 1 && prevStepParamCount == 1 &&
+                ((curStep.paramValues[0].equals("ellps", "WGS84") &&
+                  prevStep.paramValues[0].equals("ellps", "GRS80")) ||
+                 (curStep.paramValues[0].equals("ellps", "GRS80") &&
+                  prevStep.paramValues[0].equals("ellps", "WGS84")))) {
+                ++iterCur;
+                d->steps_.erase(iterPrev, iterCur);
+                changeDone = true;
+                break;
+            }
+
+            if (curStep.name == "helmert" && prevStep.name == "helmert" &&
+                !curStep.inverted && !prevStep.inverted &&
+                curStepParamCount == 3 &&
+                curStepParamCount == prevStepParamCount) {
+                std::map<std::string, double> leftParamsMap;
+                std::map<std::string, double> rightParamsMap;
+                try {
+                    for (const auto &kv : prevStep.paramValues) {
+                        leftParamsMap[kv.key] = c_locale_stod(kv.value);
+                    }
+                    for (const auto &kv : curStep.paramValues) {
+                        rightParamsMap[kv.key] = c_locale_stod(kv.value);
+                    }
+                } catch (const std::invalid_argument &) {
+                    break;
+                }
+                const std::string x("x");
+                const std::string y("y");
+                const std::string z("z");
+                if (leftParamsMap.find(x) != leftParamsMap.end() &&
+                    leftParamsMap.find(y) != leftParamsMap.end() &&
+                    leftParamsMap.find(z) != leftParamsMap.end() &&
+                    rightParamsMap.find(x) != rightParamsMap.end() &&
+                    rightParamsMap.find(y) != rightParamsMap.end() &&
+                    rightParamsMap.find(z) != rightParamsMap.end()) {
+
+                    const double xSum = leftParamsMap[x] + rightParamsMap[x];
+                    const double ySum = leftParamsMap[y] + rightParamsMap[y];
+                    const double zSum = leftParamsMap[z] + rightParamsMap[z];
+                    if (xSum == 0.0 && ySum == 0.0 && zSum == 0.0) {
+                        ++iterCur;
+                        d->steps_.erase(iterPrev, iterCur);
+                    } else {
+                        prevStep.paramValues[0] =
+                            Step::KeyValue("x", internal::toString(xSum));
+                        prevStep.paramValues[1] =
+                            Step::KeyValue("y", internal::toString(ySum));
+                        prevStep.paramValues[2] =
+                            Step::KeyValue("z", internal::toString(zSum));
+
+                        d->steps_.erase(iterCur);
+                    }
+                    changeDone = true;
+                    break;
+                }
+            }
+
+            // hermert followed by its inverse is a no-op
+            if (curStep.name == "helmert" && prevStep.name == "helmert" &&
+                !curStep.inverted && !prevStep.inverted &&
+                curStepParamCount == prevStepParamCount) {
+                std::set<std::string> leftParamsSet;
+                std::set<std::string> rightParamsSet;
+                std::map<std::string, std::string> leftParamsMap;
+                std::map<std::string, std::string> rightParamsMap;
+                for (const auto &kv : prevStep.paramValues) {
+                    leftParamsSet.insert(kv.key);
+                    leftParamsMap[kv.key] = kv.value;
+                }
+                for (const auto &kv : curStep.paramValues) {
+                    rightParamsSet.insert(kv.key);
+                    rightParamsMap[kv.key] = kv.value;
+                }
+                if (leftParamsSet == rightParamsSet) {
+                    bool doErase = true;
+                    try {
+                        for (const auto &param : leftParamsSet) {
+                            if (param == "convention" || param == "t_epoch" ||
+                                param == "t_obs") {
+                                if (leftParamsMap[param] !=
+                                    rightParamsMap[param]) {
+                                    doErase = false;
+                                    break;
+                                }
+                            } else if (c_locale_stod(leftParamsMap[param]) !=
+                                       -c_locale_stod(rightParamsMap[param])) {
+                                doErase = false;
+                                break;
+                            }
+                        }
+                    } catch (const std::invalid_argument &) {
+                        break;
+                    }
+                    if (doErase) {
+                        ++iterCur;
+                        d->steps_.erase(iterPrev, iterCur);
+                        changeDone = true;
+                        break;
+                    }
+                }
+            }
+
+            // detect a step and its inverse
+            if (curStep.inverted != prevStep.inverted &&
+                curStep.name == prevStep.name &&
+                curStepParamCount == prevStepParamCount) {
+                bool allSame = true;
+                for (size_t j = 0; j < curStepParamCount; j++) {
+                    if (curStep.paramValues[j] != prevStep.paramValues[j]) {
+                        allSame = false;
+                        break;
+                    }
+                }
+                if (allSame) {
+                    ++iterCur;
+                    d->steps_.erase(iterPrev, iterCur);
+                    changeDone = true;
+                    break;
+                }
+            }
+        }
+    } while (changeDone);
+
+    if (d->steps_.size() > 1 ||
+        (d->steps_.size() == 1 &&
+         (d->steps_.front().inverted || !d->globalParamValues_.empty()))) {
+        d->appendToResult("+proj=pipeline");
+
+        for (const auto &paramValue : d->globalParamValues_) {
+            d->appendToResult("+");
+            d->result_ += paramValue.key;
+            if (!paramValue.value.empty()) {
+                d->result_ += "=";
+                d->result_ += paramValue.value;
+            }
+        }
+    }
+
+    for (const auto &step : d->steps_) {
+        if (!d->result_.empty()) {
+            d->appendToResult("+step");
+        }
+        if (step.inverted) {
+            d->appendToResult("+inv");
+        }
+        if (!step.name.empty()) {
+            d->appendToResult(step.isInit ? "+init=" : "+proj=");
+            d->result_ += step.name;
+        }
+        for (const auto &paramValue : step.paramValues) {
+            d->appendToResult("+");
+            d->result_ += paramValue.key;
+            if (!paramValue.value.empty()) {
+                d->result_ += "=";
+                d->result_ += paramValue.value;
+            }
+        }
+    }
+    return d->result_;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+PROJStringFormatter::Convention PROJStringFormatter::convention() const {
+    return d->convention_;
+}
+
+// ---------------------------------------------------------------------------
+
+bool PROJStringFormatter::getUseETMercForTMerc(bool &settingSetOut) const {
+    settingSetOut = d->useETMercForTMercSet_;
+    return d->useETMercForTMerc_;
+}
+
+// ---------------------------------------------------------------------------
+
+void PROJStringFormatter::setCoordinateOperationOptimizations(bool enable) {
+    d->coordOperationOptimizations_ = enable;
+}
+
+// ---------------------------------------------------------------------------
+
+void PROJStringFormatter::Private::appendToResult(const char *str) {
+    if (!result_.empty()) {
+        result_ += " ";
+    }
+    result_ += str;
+}
+
+// ---------------------------------------------------------------------------
+
+static void
+PROJStringSyntaxParser(const std::string &projString, std::vector<Step> &steps,
+                       std::vector<Step::KeyValue> &globalParamValues,
+                       std::string &title, std::string &vunits,
+                       std::string &vto_meter) {
+    std::string word;
+    std::istringstream iss(projString, std::istringstream::in);
+    bool inverted = false;
+    bool prevWasStep = false;
+    bool inProj = false;
+    bool inPipeline = false;
+    bool prevWasTitle = false;
+    bool prevWasInit = false;
+
+    while (iss >> word) {
+        if (word[0] == '+') {
+            word = word.substr(1);
+        } else if (prevWasTitle && word.find('=') == std::string::npos) {
+            title += " ";
+            title += word;
+            continue;
+        }
+
+        prevWasTitle = false;
+        if (word == "proj=pipeline") {
+            if (inPipeline) {
+                throw ParsingException("nested pipeline not supported");
+            }
+            inverted = false;
+            prevWasStep = false;
+            inProj = true;
+            inPipeline = true;
+        } else if (word == "step") {
+            if (!inPipeline) {
+                throw ParsingException("+step found outside pipeline");
+            }
+            inverted = false;
+            prevWasStep = true;
+            prevWasInit = false;
+        } else if (word == "inv") {
+            if (prevWasStep) {
+                inverted = true;
+            } else {
+                if (steps.empty()) {
+                    throw ParsingException("+inv found at unexpected place");
+                }
+                steps.back().inverted = true;
+            }
+            prevWasStep = false;
+        } else if (starts_with(word, "proj=")) {
+            auto stepName = word.substr(strlen("proj="));
+            if (prevWasInit) {
+                steps.back() = Step();
+                prevWasInit = false;
+            } else {
+                steps.push_back(Step());
+            }
+            steps.back().name = stepName;
+            steps.back().inverted = inverted;
+            prevWasStep = false;
+            inProj = true;
+        } else if (starts_with(word, "init=")) {
+            if (prevWasInit) {
+                throw ParsingException("+init= found at unexpected place");
+            }
+            auto initName = word.substr(strlen("init="));
+            steps.push_back(Step());
+            steps.back().name = initName;
+            steps.back().isInit = true;
+            steps.back().inverted = inverted;
+            prevWasStep = false;
+            prevWasInit = true;
+            inProj = true;
+        } else if (inProj) {
+            const auto pos = word.find('=');
+            auto key = word.substr(0, pos);
+            auto pair = (pos != std::string::npos)
+                            ? Step::KeyValue(key, word.substr(pos + 1))
+                            : Step::KeyValue(key);
+            if (steps.empty()) {
+                globalParamValues.push_back(pair);
+            } else {
+                steps.back().paramValues.push_back(pair);
+            }
+            prevWasStep = false;
+        } else if (starts_with(word, "vunits=")) {
+            vunits = word.substr(strlen("vunits="));
+        } else if (starts_with(word, "vto_meter=")) {
+            vto_meter = word.substr(strlen("vto_meter="));
+        } else if (starts_with(word, "title=")) {
+            title = word.substr(strlen("title="));
+            prevWasTitle = true;
+        } else {
+            throw ParsingException("Unexpected token: " + word);
+        }
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+void PROJStringFormatter::ingestPROJString(
+    const std::string &str) // throw ParsingException
+{
+    std::vector<Step> steps;
+    std::string title;
+    std::string vunits;
+    std::string vto_meter;
+    PROJStringSyntaxParser(str, steps, d->globalParamValues_, title, vunits,
+                           vto_meter);
+    d->steps_.insert(d->steps_.end(), steps.begin(), steps.end());
+}
+
+// ---------------------------------------------------------------------------
+
+void PROJStringFormatter::startInversion() {
+    PROJStringFormatter::Private::InversionStackElt elt;
+    elt.startIter = d->steps_.end();
+    if (elt.startIter != d->steps_.begin()) {
+        elt.iterValid = true;
+        --elt.startIter; // point to the last valid element
+    } else {
+        elt.iterValid = false;
+    }
+    elt.currentInversionState =
+        !d->inversionStack_.back().currentInversionState;
+    d->inversionStack_.push_back(elt);
+}
+
+// ---------------------------------------------------------------------------
+
+void PROJStringFormatter::stopInversion() {
+    assert(!d->inversionStack_.empty());
+    auto startIter = d->inversionStack_.back().startIter;
+    if (!d->inversionStack_.back().iterValid) {
+        startIter = d->steps_.begin();
+    } else {
+        ++startIter; // advance after the last valid element we marked above
+    }
+    // Invert the inversion status of the steps between the start point and
+    // the current end of steps
+    for (auto iter = startIter; iter != d->steps_.end(); ++iter) {
+        iter->inverted = !iter->inverted;
+    }
+    // And reverse the order of steps in that range as well.
+    std::reverse(startIter, d->steps_.end());
+    d->inversionStack_.pop_back();
+}
+
+// ---------------------------------------------------------------------------
+
+bool PROJStringFormatter::isInverted() const {
+    return d->inversionStack_.back().currentInversionState;
+}
+
+// ---------------------------------------------------------------------------
+
+void PROJStringFormatter::Private::addStep() { steps_.emplace_back(Step()); }
+
+// ---------------------------------------------------------------------------
+
+void PROJStringFormatter::addStep(const char *stepName) {
+    d->addStep();
+    d->steps_.back().name.assign(stepName);
+}
+
+// ---------------------------------------------------------------------------
+
+void PROJStringFormatter::addStep(const std::string &stepName) {
+    d->addStep();
+    d->steps_.back().name = stepName;
+}
+
+// ---------------------------------------------------------------------------
+
+void PROJStringFormatter::setCurrentStepInverted(bool inverted) {
+    assert(!d->steps_.empty());
+    d->steps_.back().inverted = inverted;
+}
+
+// ---------------------------------------------------------------------------
+
+bool PROJStringFormatter::hasParam(const char *paramName) const {
+    if (!d->steps_.empty()) {
+        for (const auto &paramValue : d->steps_.back().paramValues) {
+            if (paramValue.keyEquals(paramName)) {
+                return true;
+            }
+        }
+    }
+    return false;
+}
+
+// ---------------------------------------------------------------------------
+
+void PROJStringFormatter::addNoDefs(bool b) { d->addNoDefs_ = b; }
+
+// ---------------------------------------------------------------------------
+
+bool PROJStringFormatter::getAddNoDefs() const { return d->addNoDefs_; }
+
+// ---------------------------------------------------------------------------
+
+void PROJStringFormatter::addParam(const std::string &paramName) {
+    if (d->steps_.empty()) {
+        d->addStep();
+    }
+    d->steps_.back().paramValues.push_back(Step::KeyValue(paramName));
+}
+
+// ---------------------------------------------------------------------------
+
+void PROJStringFormatter::addParam(const char *paramName, int val) {
+    addParam(std::string(paramName), val);
+}
+
+void PROJStringFormatter::addParam(const std::string &paramName, int val) {
+    addParam(paramName, internal::toString(val));
+}
+
+// ---------------------------------------------------------------------------
+
+static std::string formatToString(double val) {
+    if (std::abs(val * 10 - std::round(val * 10)) < 1e-8) {
+        // For the purpose of
+        // https://www.epsg-registry.org/export.htm?wkt=urn:ogc:def:crs:EPSG::27561
+        // Latitude of natural of origin to be properly rounded from 55 grad
+        // to
+        // 49.5 deg
+        val = std::round(val * 10) / 10;
+    }
+    return normalizeSerializedString(internal::toString(val));
+}
+
+// ---------------------------------------------------------------------------
+
+void PROJStringFormatter::addParam(const char *paramName, double val) {
+    addParam(std::string(paramName), val);
+}
+
+void PROJStringFormatter::addParam(const std::string &paramName, double val) {
+    addParam(paramName, formatToString(val));
+}
+
+// ---------------------------------------------------------------------------
+
+void PROJStringFormatter::addParam(const char *paramName,
+                                   const std::vector<double> &vals) {
+    std::string paramValue;
+    for (size_t i = 0; i < vals.size(); ++i) {
+        if (i > 0) {
+            paramValue += ',';
+        }
+        paramValue += formatToString(vals[i]);
+    }
+    addParam(paramName, paramValue);
+}
+
+// ---------------------------------------------------------------------------
+
+void PROJStringFormatter::addParam(const char *paramName, const char *val) {
+    addParam(std::string(paramName), val);
+}
+
+void PROJStringFormatter::addParam(const char *paramName,
+                                   const std::string &val) {
+    addParam(std::string(paramName), val);
+}
+
+void PROJStringFormatter::addParam(const std::string &paramName,
+                                   const char *val) {
+    addParam(paramName, std::string(val));
+}
+
+// ---------------------------------------------------------------------------
+
+void PROJStringFormatter::addParam(const std::string &paramName,
+                                   const std::string &val) {
+    if (d->steps_.empty()) {
+        d->addStep();
+    }
+    d->steps_.back().paramValues.push_back(Step::KeyValue(paramName, val));
+}
+
+// ---------------------------------------------------------------------------
+
+void PROJStringFormatter::setTOWGS84Parameters(
+    const std::vector<double> &params) {
+    d->toWGS84Parameters_ = params;
+}
+
+// ---------------------------------------------------------------------------
+
+const std::vector<double> &PROJStringFormatter::getTOWGS84Parameters() const {
+    return d->toWGS84Parameters_;
+}
+
+// ---------------------------------------------------------------------------
+
+std::set<std::string> PROJStringFormatter::getUsedGridNames() const {
+    std::set<std::string> res;
+    for (const auto &step : d->steps_) {
+        for (const auto &param : step.paramValues) {
+            if (param.keyEquals("grids")) {
+                res.insert(param.value);
+            }
+        }
+    }
+    return res;
+}
+
+// ---------------------------------------------------------------------------
+
+void PROJStringFormatter::setVDatumExtension(const std::string &filename) {
+    d->vDatumExtension_ = filename;
+}
+
+// ---------------------------------------------------------------------------
+
+const std::string &PROJStringFormatter::getVDatumExtension() const {
+    return d->vDatumExtension_;
+}
+
+// ---------------------------------------------------------------------------
+
+void PROJStringFormatter::setHDatumExtension(const std::string &filename) {
+    d->hDatumExtension_ = filename;
+}
+
+// ---------------------------------------------------------------------------
+
+const std::string &PROJStringFormatter::getHDatumExtension() const {
+    return d->hDatumExtension_;
+}
+
+// ---------------------------------------------------------------------------
+
+void PROJStringFormatter::setOmitProjLongLatIfPossible(bool omit) {
+    assert(d->omitProjLongLatIfPossible_ ^ omit);
+    d->omitProjLongLatIfPossible_ = omit;
+}
+
+// ---------------------------------------------------------------------------
+
+bool PROJStringFormatter::omitProjLongLatIfPossible() const {
+    return d->omitProjLongLatIfPossible_;
+}
+
+// ---------------------------------------------------------------------------
+
+void PROJStringFormatter::setOmitZUnitConversion(bool omit) {
+    assert(d->omitZUnitConversion_ ^ omit);
+    d->omitZUnitConversion_ = omit;
+}
+
+// ---------------------------------------------------------------------------
+
+bool PROJStringFormatter::omitZUnitConversion() const {
+    return d->omitZUnitConversion_;
+}
+
+// ---------------------------------------------------------------------------
+
+const DatabaseContextPtr &PROJStringFormatter::databaseContext() const {
+    return d->dbContext_;
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+struct PROJStringParser::Private {
+    DatabaseContextPtr dbContext_{};
+    bool usePROJ4InitRules_ = false;
+    std::vector<std::string> warningList_{};
+
+    std::string projString_{};
+
+    std::vector<Step> steps_{};
+    std::vector<Step::KeyValue> globalParamValues_{};
+    std::string title_{};
+
+    template <class T>
+    // cppcheck-suppress functionStatic
+    bool hasParamValue(const Step &step, const T key) {
+        for (const auto &pair : globalParamValues_) {
+            if (ci_equal(pair.key, key)) {
+                return true;
+            }
+        }
+        for (const auto &pair : step.paramValues) {
+            if (ci_equal(pair.key, key)) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    template <class T>
+    // cppcheck-suppress functionStatic
+    const std::string &getParamValue(const Step &step, const T key) {
+        for (const auto &pair : globalParamValues_) {
+            if (ci_equal(pair.key, key)) {
+                return pair.value;
+            }
+        }
+        for (const auto &pair : step.paramValues) {
+            if (ci_equal(pair.key, key)) {
+                return pair.value;
+            }
+        }
+        return emptyString;
+    }
+
+    // cppcheck-suppress functionStatic
+    const std::string &getParamValueK(const Step &step) {
+        for (const auto &pair : step.paramValues) {
+            if (ci_equal(pair.key, "k") || ci_equal(pair.key, "k_0")) {
+                return pair.value;
+            }
+        }
+        return emptyString;
+    }
+
+    // cppcheck-suppress functionStatic
+    std::string guessBodyName(double a);
+
+    PrimeMeridianNNPtr buildPrimeMeridian(const Step &step);
+    GeodeticReferenceFrameNNPtr buildDatum(const Step &step,
+                                           const std::string &title);
+    GeographicCRSNNPtr buildGeographicCRS(int iStep, int iUnitConvert,
+                                          int iAxisSwap, bool ignoreVUnits,
+                                          bool ignorePROJAxis);
+    GeodeticCRSNNPtr buildGeocentricCRS(int iStep, int iUnitConvert);
+    CRSNNPtr buildProjectedCRS(int iStep, GeographicCRSNNPtr geogCRS,
+                               int iUnitConvert, int iAxisSwap);
+    CRSNNPtr buildBoundOrCompoundCRSIfNeeded(int iStep, CRSNNPtr crs);
+    UnitOfMeasure buildUnit(const Step &step, const std::string &unitsParamName,
+                            const std::string &toMeterParamName);
+    CoordinateOperationNNPtr buildHelmertTransformation(
+        int iStep, int iFirstAxisSwap = -1, int iFirstUnitConvert = -1,
+        int iFirstGeogStep = -1, int iSecondGeogStep = -1,
+        int iSecondAxisSwap = -1, int iSecondUnitConvert = -1);
+    CoordinateOperationNNPtr buildMolodenskyTransformation(
+        int iStep, int iFirstAxisSwap = -1, int iFirstUnitConvert = -1,
+        int iFirstGeogStep = -1, int iSecondGeogStep = -1,
+        int iSecondAxisSwap = -1, int iSecondUnitConvert = -1);
+
+    enum class AxisType { REGULAR, NORTH_POLE, SOUTH_POLE };
+
+    std::vector<CoordinateSystemAxisNNPtr>
+    processAxisSwap(const Step &step, const UnitOfMeasure &unit, int iAxisSwap,
+                    AxisType axisType, bool ignorePROJAxis);
+
+    EllipsoidalCSNNPtr buildEllipsoidalCS(int iStep, int iUnitConvert,
+                                          int iAxisSwap, bool ignoreVUnits,
+                                          bool ignorePROJAxis);
+};
+
+// ---------------------------------------------------------------------------
+
+PROJStringParser::PROJStringParser() : d(internal::make_unique<Private>()) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+PROJStringParser::~PROJStringParser() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Attach a database context, to allow queries in it if needed.
+ */
+PROJStringParser &
+PROJStringParser::attachDatabaseContext(const DatabaseContextPtr &dbContext) {
+    d->dbContext_ = dbContext;
+    return *this;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Set how init=epsg:XXXX syntax should be interpreted.
+ *
+ * @param enable When set to true,
+ * init=epsg:XXXX syntax will be allowed and will be interpreted according to
+ * PROJ.4 and PROJ.5 rules, that is geodeticCRS will have longitude, latitude
+ * order and will expect/output coordinates in radians. ProjectedCRS will have
+ * easting, northing axis order (except the ones with Transverse Mercator South
+ * Orientated projection).
+ */
+PROJStringParser &PROJStringParser::setUsePROJ4InitRules(bool enable) {
+    d->usePROJ4InitRules_ = enable;
+    return *this;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the list of warnings found during parsing.
+ */
+std::vector<std::string> PROJStringParser::warningList() const {
+    return d->warningList_;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+// ---------------------------------------------------------------------------
+
+static const struct LinearUnitDesc {
+    const char *projName;
+    const char *convToMeter;
+    const char *name;
+    int epsgCode;
+} linearUnitDescs[] = {
+    {"mm", "0.001", "millimetre", 1025},
+    {"cm", "0.01", "centimetre", 1033},
+    {"m", "1.0", "metre", 9001},
+    {"meter", "1.0", "metre", 9001}, // alternative
+    {"metre", "1.0", "metre", 9001}, // alternative
+    {"ft", "0.3048", "foot", 9002},
+    {"us-ft", "0.3048006096012192", "US survey foot", 9003},
+    {"fath", "1.8288", "fathom", 9014},
+    {"kmi", "1852", "nautical mile", 9030},
+    {"us-ch", "20.11684023368047", "US survey chain", 9033},
+    {"us-mi", "1609.347218694437", "US survey mile", 9035},
+    {"km", "1000.0", "kilometre", 9036},
+    {"ind-ft", "0.30479841", "Indian foot (1937)", 9081},
+    {"ind-yd", "0.91439523", "Indian yard (1937)", 9085},
+    {"mi", "1609.344", "Statute mile", 9093},
+    {"yd", "0.9144", "yard", 9096},
+    {"ch", "20.1168", "chain", 9097},
+    {"link", "0.201168", "link", 9098},
+    {"dm", "0.1", "decimetre", 0},                       // no EPSG equivalent
+    {"in", "0.0254", "inch", 0},                         // no EPSG equivalent
+    {"us-in", "0.025400050800101", "US survey inch", 0}, // no EPSG equivalent
+    {"us-yd", "0.914401828803658", "US survey yard", 0}, // no EPSG equivalent
+    {"ind-ch", "20.11669506", "Indian chain", 0},        // no EPSG equivalent
+};
+
+static const LinearUnitDesc *getLinearUnits(const std::string &projName) {
+    for (const auto &desc : linearUnitDescs) {
+        if (desc.projName == projName)
+            return &desc;
+    }
+    return nullptr;
+}
+
+static const LinearUnitDesc *getLinearUnits(double toMeter) {
+    for (const auto &desc : linearUnitDescs) {
+        if (std::fabs(c_locale_stod(desc.convToMeter) - toMeter) <
+            1e-10 * toMeter) {
+            return &desc;
+        }
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+static UnitOfMeasure _buildUnit(const LinearUnitDesc *unitsMatch) {
+    std::string unitsCode;
+    if (unitsMatch->epsgCode) {
+        std::ostringstream buffer;
+        buffer.imbue(std::locale::classic());
+        buffer << unitsMatch->epsgCode;
+        unitsCode = buffer.str();
+    }
+    return UnitOfMeasure(
+        unitsMatch->name, c_locale_stod(unitsMatch->convToMeter),
+        UnitOfMeasure::Type::LINEAR,
+        unitsMatch->epsgCode ? Identifier::EPSG : std::string(), unitsCode);
+}
+
+// ---------------------------------------------------------------------------
+
+static UnitOfMeasure _buildUnit(double to_meter_value) {
+    // TODO: look-up in EPSG catalog
+    return UnitOfMeasure("unknown", to_meter_value,
+                         UnitOfMeasure::Type::LINEAR);
+}
+
+// ---------------------------------------------------------------------------
+
+UnitOfMeasure
+PROJStringParser::Private::buildUnit(const Step &step,
+                                     const std::string &unitsParamName,
+                                     const std::string &toMeterParamName) {
+    UnitOfMeasure unit = UnitOfMeasure::METRE;
+    const LinearUnitDesc *unitsMatch = nullptr;
+    const auto &projUnits = getParamValue(step, unitsParamName);
+    if (!projUnits.empty()) {
+        unitsMatch = getLinearUnits(projUnits);
+        if (unitsMatch == nullptr) {
+            throw ParsingException("unhandled " + unitsParamName + "=" +
+                                   projUnits);
+        }
+    }
+
+    const auto &toMeter = getParamValue(step, toMeterParamName);
+    if (!toMeter.empty()) {
+        double to_meter_value;
+        try {
+            to_meter_value = c_locale_stod(toMeter);
+        } catch (const std::invalid_argument &) {
+            throw ParsingException("invalid value for " + toMeterParamName);
+        }
+        unitsMatch = getLinearUnits(to_meter_value);
+        if (unitsMatch == nullptr) {
+            unit = _buildUnit(to_meter_value);
+        }
+    }
+
+    if (unitsMatch) {
+        unit = _buildUnit(unitsMatch);
+    }
+
+    return unit;
+}
+
+// ---------------------------------------------------------------------------
+
+static const struct DatumDesc {
+    const char *projName;
+    const char *gcsName;
+    int gcsCode;
+    const char *datumName;
+    int datumCode;
+    const char *ellipsoidName;
+    int ellipsoidCode;
+    double a;
+    double rf;
+} datumDescs[] = {
+    {"GGRS87", "GGRS87", 4121, "Greek Geodetic Reference System 1987", 6121,
+     "GRS 1980", 7019, 6378137, 298.257222101},
+    {"postdam", "DHDN", 4314, "Deutsches Hauptdreiecksnetz", 6314,
+     "Bessel 1841", 7004, 6377397.155, 299.1528128},
+    {"carthage", "Carthage", 4223, "Carthage", 6223, "Clarke 1880 (IGN)", 7011,
+     6378249.2, 293.4660213},
+    {"hermannskogel", "MGI", 4312, "Militar-Geographische Institut", 6312,
+     "Bessel 1841", 7004, 6377397.155, 299.1528128},
+    {"ire65", "TM65", 4299, "TM65", 6299, "Airy Modified 1849", 7002,
+     6377340.189, 299.3249646},
+    {"nzgd49", "NZGD49", 4272, "New Zealand Geodetic Datum 1949", 6272,
+     "International 1924", 7022, 6378388, 297},
+    {"OSGB36", "OSGB 1936", 4277, "OSGB 1936", 6277, "Airy 1830", 7001,
+     6377563.396, 299.3249646},
+};
+
+// ---------------------------------------------------------------------------
+
+static bool isGeographicStep(const std::string &name) {
+    return name == "longlat" || name == "lonlat" || name == "latlong" ||
+           name == "latlon";
+}
+
+// ---------------------------------------------------------------------------
+
+static bool isGeocentricStep(const std::string &name) {
+    return name == "geocent" || name == "cart";
+}
+
+// ---------------------------------------------------------------------------
+
+static bool isProjectedStep(const std::string &name) {
+    if (name == "etmerc" || name == "utm" ||
+        !getMappingsFromPROJName(name).empty()) {
+        return true;
+    }
+    // IMPROVE ME: have a better way of distinguishing projections from
+    // other
+    // transformations.
+    if (name == "pipeline" || name == "geoc" || name == "deformation" ||
+        name == "helmert" || name == "hgridshift" || name == "molodensky" ||
+        name == "vgridshit") {
+        return false;
+    }
+    const auto *operations = proj_list_operations();
+    for (int i = 0; operations[i].id != nullptr; ++i) {
+        if (name == operations[i].id) {
+            return true;
+        }
+    }
+    return false;
+}
+
+// ---------------------------------------------------------------------------
+
+static PropertyMap createMapWithUnknownName() {
+    return PropertyMap().set(common::IdentifiedObject::NAME_KEY, "unknown");
+}
+
+// ---------------------------------------------------------------------------
+
+PrimeMeridianNNPtr
+PROJStringParser::Private::buildPrimeMeridian(const Step &step) {
+
+    PrimeMeridianNNPtr pm = PrimeMeridian::GREENWICH;
+    const auto &pmStr = getParamValue(step, "pm");
+    if (!pmStr.empty()) {
+        char *end;
+        double pmValue = dmstor(pmStr.c_str(), &end) * RAD_TO_DEG;
+        if (pmValue != HUGE_VAL && *end == '\0') {
+            pm = PrimeMeridian::create(createMapWithUnknownName(),
+                                       Angle(pmValue));
+        } else {
+            bool found = false;
+            if (pmStr == "paris") {
+                found = true;
+                pm = PrimeMeridian::PARIS;
+            }
+            auto proj_prime_meridians = proj_list_prime_meridians();
+            for (int i = 0; !found && proj_prime_meridians[i].id != nullptr;
+                 i++) {
+                if (pmStr == proj_prime_meridians[i].id) {
+                    found = true;
+                    std::string name = static_cast<char>(::toupper(pmStr[0])) +
+                                       pmStr.substr(1);
+                    pmValue = dmstor(proj_prime_meridians[i].defn, nullptr) *
+                              RAD_TO_DEG;
+                    pm = PrimeMeridian::create(
+                        PropertyMap().set(IdentifiedObject::NAME_KEY, name),
+                        Angle(pmValue));
+                    break;
+                }
+            }
+            if (!found) {
+                throw ParsingException("unknown pm " + pmStr);
+            }
+        }
+    }
+    return pm;
+}
+
+// ---------------------------------------------------------------------------
+
+std::string PROJStringParser::Private::guessBodyName(double a) {
+    return Ellipsoid::guessBodyName(dbContext_, a);
+}
+
+// ---------------------------------------------------------------------------
+
+GeodeticReferenceFrameNNPtr
+PROJStringParser::Private::buildDatum(const Step &step,
+                                      const std::string &title) {
+
+    const auto &ellpsStr = getParamValue(step, "ellps");
+    const auto &datumStr = getParamValue(step, "datum");
+    const auto &RStr = getParamValue(step, "R");
+    const auto &aStr = getParamValue(step, "a");
+    const auto &bStr = getParamValue(step, "b");
+    const auto &rfStr = getParamValue(step, "rf");
+    const auto &fStr = getParamValue(step, "f");
+    const auto &esStr = getParamValue(step, "es");
+    const auto &eStr = getParamValue(step, "e");
+    double a = -1.0;
+    double b = -1.0;
+    double rf = -1.0;
+    const util::optional<std::string> optionalEmptyString{};
+    const bool numericParamPresent =
+        !RStr.empty() || !aStr.empty() || !bStr.empty() || !rfStr.empty() ||
+        !fStr.empty() || !esStr.empty() || !eStr.empty();
+
+    PrimeMeridianNNPtr pm(buildPrimeMeridian(step));
+    PropertyMap grfMap;
+
+    // It is arguable that we allow the prime meridian of a datum defined by
+    // its name to be overriden, but this is found at least in a regression test
+    // of GDAL. So let's keep the ellipsoid part of the datum in that case and
+    // use the specified prime meridian.
+    const auto overridePmIfNeeded =
+        [&pm](const GeodeticReferenceFrameNNPtr &grf) {
+            if (pm->_isEquivalentTo(PrimeMeridian::GREENWICH.get())) {
+                return grf;
+            } else {
+                return GeodeticReferenceFrame::create(
+                    PropertyMap().set(IdentifiedObject::NAME_KEY,
+                                      "Unknown based on " +
+                                          grf->ellipsoid()->nameStr() +
+                                          " ellipsoid"),
+                    grf->ellipsoid(), grf->anchorDefinition(), pm);
+            }
+        };
+
+    // R take precedence
+    if (!RStr.empty()) {
+        double R;
+        try {
+            R = c_locale_stod(RStr);
+        } catch (const std::invalid_argument &) {
+            throw ParsingException("Invalid R value");
+        }
+        auto ellipsoid = Ellipsoid::createSphere(createMapWithUnknownName(),
+                                                 Length(R), guessBodyName(R));
+        return GeodeticReferenceFrame::create(
+            grfMap.set(IdentifiedObject::NAME_KEY,
+                       title.empty() ? "unknown" : title.c_str()),
+            ellipsoid, optionalEmptyString, fixupPrimeMeridan(ellipsoid, pm));
+    }
+
+    if (!datumStr.empty()) {
+        auto l_datum = [&datumStr, &overridePmIfNeeded, &grfMap,
+                        &optionalEmptyString, &pm]() {
+            if (datumStr == "WGS84") {
+                return overridePmIfNeeded(GeodeticReferenceFrame::EPSG_6326);
+            } else if (datumStr == "NAD83") {
+                return overridePmIfNeeded(GeodeticReferenceFrame::EPSG_6269);
+            } else if (datumStr == "NAD27") {
+                return overridePmIfNeeded(GeodeticReferenceFrame::EPSG_6267);
+            } else {
+
+                for (const auto &datumDesc : datumDescs) {
+                    if (datumStr == datumDesc.projName) {
+                        (void)datumDesc.gcsName; // to please cppcheck
+                        (void)datumDesc.gcsCode; // to please cppcheck
+                        auto ellipsoid = Ellipsoid::createFlattenedSphere(
+                            grfMap
+                                .set(IdentifiedObject::NAME_KEY,
+                                     datumDesc.ellipsoidName)
+                                .set(Identifier::CODESPACE_KEY,
+                                     Identifier::EPSG)
+                                .set(Identifier::CODE_KEY,
+                                     datumDesc.ellipsoidCode),
+                            Length(datumDesc.a), Scale(datumDesc.rf));
+                        return GeodeticReferenceFrame::create(
+                            grfMap
+                                .set(IdentifiedObject::NAME_KEY,
+                                     datumDesc.datumName)
+                                .set(Identifier::CODESPACE_KEY,
+                                     Identifier::EPSG)
+                                .set(Identifier::CODE_KEY, datumDesc.datumCode),
+                            ellipsoid, optionalEmptyString, pm);
+                    }
+                }
+            }
+            throw ParsingException("unknown datum " + datumStr);
+        }();
+        if (!numericParamPresent) {
+            return l_datum;
+        }
+        a = l_datum->ellipsoid()->semiMajorAxis().getSIValue();
+        rf = l_datum->ellipsoid()->computedInverseFlattening();
+    }
+
+    else if (!ellpsStr.empty()) {
+        auto l_datum = [&ellpsStr, &title, &grfMap, &optionalEmptyString,
+                        &pm]() {
+            if (ellpsStr == "WGS84") {
+                return GeodeticReferenceFrame::create(
+                    grfMap.set(IdentifiedObject::NAME_KEY,
+                               title.empty()
+                                   ? "Unknown based on WGS84 ellipsoid"
+                                   : title.c_str()),
+                    Ellipsoid::WGS84, optionalEmptyString, pm);
+            } else if (ellpsStr == "GRS80") {
+                return GeodeticReferenceFrame::create(
+                    grfMap.set(IdentifiedObject::NAME_KEY,
+                               title.empty()
+                                   ? "Unknown based on GRS80 ellipsoid"
+                                   : title.c_str()),
+                    Ellipsoid::GRS1980, optionalEmptyString, pm);
+            } else {
+                auto proj_ellps = proj_list_ellps();
+                for (int i = 0; proj_ellps[i].id != nullptr; i++) {
+                    if (ellpsStr == proj_ellps[i].id) {
+                        assert(strncmp(proj_ellps[i].major, "a=", 2) == 0);
+                        const double a_iter =
+                            c_locale_stod(proj_ellps[i].major + 2);
+                        EllipsoidPtr ellipsoid;
+                        PropertyMap ellpsMap;
+                        if (strncmp(proj_ellps[i].ell, "b=", 2) == 0) {
+                            const double b_iter =
+                                c_locale_stod(proj_ellps[i].ell + 2);
+                            ellipsoid =
+                                Ellipsoid::createTwoAxis(
+                                    ellpsMap.set(IdentifiedObject::NAME_KEY,
+                                                 proj_ellps[i].name),
+                                    Length(a_iter), Length(b_iter))
+                                    .as_nullable();
+                        } else {
+                            assert(strncmp(proj_ellps[i].ell, "rf=", 3) == 0);
+                            const double rf_iter =
+                                c_locale_stod(proj_ellps[i].ell + 3);
+                            ellipsoid =
+                                Ellipsoid::createFlattenedSphere(
+                                    ellpsMap.set(IdentifiedObject::NAME_KEY,
+                                                 proj_ellps[i].name),
+                                    Length(a_iter), Scale(rf_iter))
+                                    .as_nullable();
+                        }
+                        return GeodeticReferenceFrame::create(
+                            grfMap.set(IdentifiedObject::NAME_KEY,
+                                       title.empty()
+                                           ? std::string("Unknown based on ") +
+                                                 proj_ellps[i].name +
+                                                 " ellipsoid"
+                                           : title),
+                            NN_NO_CHECK(ellipsoid), optionalEmptyString, pm);
+                    }
+                }
+                throw ParsingException("unknown ellipsoid " + ellpsStr);
+            }
+        }();
+        if (!numericParamPresent) {
+            return l_datum;
+        }
+        a = l_datum->ellipsoid()->semiMajorAxis().getSIValue();
+        if (l_datum->ellipsoid()->semiMinorAxis().has_value()) {
+            b = l_datum->ellipsoid()->semiMinorAxis()->getSIValue();
+        } else {
+            rf = l_datum->ellipsoid()->computedInverseFlattening();
+        }
+    }
+
+    if (!aStr.empty()) {
+        try {
+            a = c_locale_stod(aStr);
+        } catch (const std::invalid_argument &) {
+            throw ParsingException("Invalid a value");
+        }
+    }
+
+    if (a > 0 && (b > 0 || !bStr.empty())) {
+        if (!bStr.empty()) {
+            try {
+                b = c_locale_stod(bStr);
+            } catch (const std::invalid_argument &) {
+                throw ParsingException("Invalid b value");
+            }
+        }
+        auto ellipsoid =
+            Ellipsoid::createTwoAxis(createMapWithUnknownName(), Length(a),
+                                     Length(b), guessBodyName(a))
+                ->identify();
+        return GeodeticReferenceFrame::create(
+            grfMap.set(IdentifiedObject::NAME_KEY,
+                       title.empty() ? "unknown" : title.c_str()),
+            ellipsoid, optionalEmptyString, fixupPrimeMeridan(ellipsoid, pm));
+    }
+
+    else if (a > 0 && (rf >= 0 || !rfStr.empty())) {
+        if (!rfStr.empty()) {
+            try {
+                rf = c_locale_stod(rfStr);
+            } catch (const std::invalid_argument &) {
+                throw ParsingException("Invalid rf value");
+            }
+        }
+        auto ellipsoid = Ellipsoid::createFlattenedSphere(
+                             createMapWithUnknownName(), Length(a), Scale(rf),
+                             guessBodyName(a))
+                             ->identify();
+        return GeodeticReferenceFrame::create(
+            grfMap.set(IdentifiedObject::NAME_KEY,
+                       title.empty() ? "unknown" : title.c_str()),
+            ellipsoid, optionalEmptyString, fixupPrimeMeridan(ellipsoid, pm));
+    }
+
+    else if (a > 0 && !fStr.empty()) {
+        double f;
+        try {
+            f = c_locale_stod(fStr);
+        } catch (const std::invalid_argument &) {
+            throw ParsingException("Invalid f value");
+        }
+        auto ellipsoid = Ellipsoid::createFlattenedSphere(
+                             createMapWithUnknownName(), Length(a),
+                             Scale(f != 0.0 ? 1.0 / f : 0.0), guessBodyName(a))
+                             ->identify();
+        return GeodeticReferenceFrame::create(
+            grfMap.set(IdentifiedObject::NAME_KEY,
+                       title.empty() ? "unknown" : title.c_str()),
+            ellipsoid, optionalEmptyString, fixupPrimeMeridan(ellipsoid, pm));
+    }
+
+    else if (a > 0 && !eStr.empty()) {
+        double e;
+        try {
+            e = c_locale_stod(eStr);
+        } catch (const std::invalid_argument &) {
+            throw ParsingException("Invalid e value");
+        }
+        double alpha = asin(e);    /* angular eccentricity */
+        double f = 1 - cos(alpha); /* = 1 - sqrt (1 - es); */
+        auto ellipsoid = Ellipsoid::createFlattenedSphere(
+                             createMapWithUnknownName(), Length(a),
+                             Scale(f != 0.0 ? 1.0 / f : 0.0), guessBodyName(a))
+                             ->identify();
+        return GeodeticReferenceFrame::create(
+            grfMap.set(IdentifiedObject::NAME_KEY,
+                       title.empty() ? "unknown" : title.c_str()),
+            ellipsoid, optionalEmptyString, fixupPrimeMeridan(ellipsoid, pm));
+    }
+
+    else if (a > 0 && !esStr.empty()) {
+        double es;
+        try {
+            es = c_locale_stod(esStr);
+        } catch (const std::invalid_argument &) {
+            throw ParsingException("Invalid es value");
+        }
+        double f = 1 - sqrt(1 - es);
+        auto ellipsoid = Ellipsoid::createFlattenedSphere(
+                             createMapWithUnknownName(), Length(a),
+                             Scale(f != 0.0 ? 1.0 / f : 0.0), guessBodyName(a))
+                             ->identify();
+        return GeodeticReferenceFrame::create(
+            grfMap.set(IdentifiedObject::NAME_KEY,
+                       title.empty() ? "unknown" : title.c_str()),
+            ellipsoid, optionalEmptyString, fixupPrimeMeridan(ellipsoid, pm));
+    }
+
+    // If only a is specified, create a sphere
+    if (a > 0 && bStr.empty() && rfStr.empty() && eStr.empty() &&
+        esStr.empty()) {
+        auto ellipsoid = Ellipsoid::createSphere(createMapWithUnknownName(),
+                                                 Length(a), guessBodyName(a));
+        return GeodeticReferenceFrame::create(
+            grfMap.set(IdentifiedObject::NAME_KEY,
+                       title.empty() ? "unknown" : title.c_str()),
+            ellipsoid, optionalEmptyString, fixupPrimeMeridan(ellipsoid, pm));
+    }
+
+    if (!bStr.empty() && aStr.empty()) {
+        throw ParsingException("b found, but a missing");
+    }
+
+    if (!rfStr.empty() && aStr.empty()) {
+        throw ParsingException("rf found, but a missing");
+    }
+
+    if (!fStr.empty() && aStr.empty()) {
+        throw ParsingException("f found, but a missing");
+    }
+
+    if (!eStr.empty() && aStr.empty()) {
+        throw ParsingException("e found, but a missing");
+    }
+
+    if (!esStr.empty() && aStr.empty()) {
+        throw ParsingException("es found, but a missing");
+    }
+
+    return overridePmIfNeeded(GeodeticReferenceFrame::EPSG_6326);
+}
+
+// ---------------------------------------------------------------------------
+
+static const MeridianPtr nullMeridian{};
+
+static CoordinateSystemAxisNNPtr
+createAxis(const std::string &name, const std::string &abbreviation,
+           const AxisDirection &direction, const common::UnitOfMeasure &unit,
+           const MeridianPtr &meridian = nullMeridian) {
+    return CoordinateSystemAxis::create(
+        PropertyMap().set(IdentifiedObject::NAME_KEY, name), abbreviation,
+        direction, unit, meridian);
+}
+
+std::vector<CoordinateSystemAxisNNPtr>
+PROJStringParser::Private::processAxisSwap(const Step &step,
+                                           const UnitOfMeasure &unit,
+                                           int iAxisSwap, AxisType axisType,
+                                           bool ignorePROJAxis) {
+    assert(iAxisSwap < 0 || ci_equal(steps_[iAxisSwap].name, "axisswap"));
+
+    const bool isGeographic = unit.type() == UnitOfMeasure::Type::ANGULAR;
+    const auto &eastName =
+        isGeographic ? AxisName::Longitude : AxisName::Easting;
+    const auto &eastAbbev =
+        isGeographic ? AxisAbbreviation::lon : AxisAbbreviation::E;
+    const auto &eastDir = isGeographic
+                              ? AxisDirection::EAST
+                              : (axisType == AxisType::NORTH_POLE)
+                                    ? AxisDirection::SOUTH
+                                    : (axisType == AxisType::SOUTH_POLE)
+                                          ? AxisDirection::NORTH
+                                          : AxisDirection::EAST;
+    CoordinateSystemAxisNNPtr east = createAxis(
+        eastName, eastAbbev, eastDir, unit,
+        (!isGeographic &&
+         (axisType == AxisType::NORTH_POLE || axisType == AxisType::SOUTH_POLE))
+            ? Meridian::create(Angle(90, UnitOfMeasure::DEGREE)).as_nullable()
+            : nullMeridian);
+
+    const auto &northName =
+        isGeographic ? AxisName::Latitude : AxisName::Northing;
+    const auto &northAbbev =
+        isGeographic ? AxisAbbreviation::lat : AxisAbbreviation::N;
+    const auto &northDir = isGeographic
+                               ? AxisDirection::NORTH
+                               : (axisType == AxisType::NORTH_POLE)
+                                     ? AxisDirection::SOUTH
+                                     : (axisType == AxisType::SOUTH_POLE)
+                                           ? AxisDirection::NORTH
+                                           : AxisDirection::NORTH;
+    CoordinateSystemAxisNNPtr north = createAxis(
+        northName, northAbbev, northDir, unit,
+        (!isGeographic && axisType == AxisType::NORTH_POLE)
+            ? Meridian::create(Angle(180, UnitOfMeasure::DEGREE)).as_nullable()
+            : (!isGeographic && axisType == AxisType::SOUTH_POLE)
+                  ? Meridian::create(Angle(0, UnitOfMeasure::DEGREE))
+                        .as_nullable()
+                  : nullMeridian);
+
+    CoordinateSystemAxisNNPtr west =
+        createAxis(isGeographic ? AxisName::Longitude : AxisName::Westing,
+                   isGeographic ? AxisAbbreviation::lon : std::string(),
+                   AxisDirection::WEST, unit);
+
+    CoordinateSystemAxisNNPtr south =
+        createAxis(isGeographic ? AxisName::Latitude : AxisName::Southing,
+                   isGeographic ? AxisAbbreviation::lat : std::string(),
+                   AxisDirection::SOUTH, unit);
+
+    std::vector<CoordinateSystemAxisNNPtr> axis{east, north};
+
+    const auto &axisStr = getParamValue(step, "axis");
+    if (!ignorePROJAxis && !axisStr.empty()) {
+        if (axisStr.size() == 3) {
+            for (int i = 0; i < 2; i++) {
+                if (axisStr[i] == 'n') {
+                    axis[i] = north;
+                } else if (axisStr[i] == 's') {
+                    axis[i] = south;
+                } else if (axisStr[i] == 'e') {
+                    axis[i] = east;
+                } else if (axisStr[i] == 'w') {
+                    axis[i] = west;
+                } else {
+                    throw ParsingException("Unhandled axis=" + axisStr);
+                }
+            }
+        } else {
+            throw ParsingException("Unhandled axis=" + axisStr);
+        }
+    } else if (iAxisSwap >= 0) {
+        const auto &stepAxisSwap = steps_[iAxisSwap];
+        const auto &orderStr = getParamValue(stepAxisSwap, "order");
+        auto orderTab = split(orderStr, ',');
+        if (orderTab.size() != 2) {
+            throw ParsingException("Unhandled order=" + orderStr);
+        }
+        if (stepAxisSwap.inverted) {
+            throw ParsingException("Unhandled +inv for +proj=axisswap");
+        }
+
+        for (size_t i = 0; i < 2; i++) {
+            if (orderTab[i] == "1") {
+                axis[i] = east;
+            } else if (orderTab[i] == "-1") {
+                axis[i] = west;
+            } else if (orderTab[i] == "2") {
+                axis[i] = north;
+            } else if (orderTab[i] == "-2") {
+                axis[i] = south;
+            } else {
+                throw ParsingException("Unhandled order=" + orderStr);
+            }
+        }
+    }
+    return axis;
+}
+
+// ---------------------------------------------------------------------------
+
+EllipsoidalCSNNPtr
+PROJStringParser::Private::buildEllipsoidalCS(int iStep, int iUnitConvert,
+                                              int iAxisSwap, bool ignoreVUnits,
+                                              bool ignorePROJAxis) {
+    const auto &step = steps_[iStep];
+    assert(iUnitConvert < 0 ||
+           ci_equal(steps_[iUnitConvert].name, "unitconvert"));
+
+    UnitOfMeasure angularUnit = UnitOfMeasure::DEGREE;
+    if (iUnitConvert >= 0) {
+        const auto &stepUnitConvert = steps_[iUnitConvert];
+        const std::string *xy_in = &getParamValue(stepUnitConvert, "xy_in");
+        const std::string *xy_out = &getParamValue(stepUnitConvert, "xy_out");
+        if (stepUnitConvert.inverted) {
+            std::swap(xy_in, xy_out);
+        }
+        if (iUnitConvert < iStep) {
+            std::swap(xy_in, xy_out);
+        }
+        if (xy_in->empty() || xy_out->empty() || *xy_in != "rad" ||
+            (*xy_out != "rad" && *xy_out != "deg" && *xy_out != "grad")) {
+            throw ParsingException("unhandled values for xy_in and/or xy_out");
+        }
+        if (*xy_out == "rad") {
+            angularUnit = UnitOfMeasure::RADIAN;
+        } else if (*xy_out == "grad") {
+            angularUnit = UnitOfMeasure::GRAD;
+        }
+    }
+
+    std::vector<CoordinateSystemAxisNNPtr> axis = processAxisSwap(
+        step, angularUnit, iAxisSwap, AxisType::REGULAR, ignorePROJAxis);
+    CoordinateSystemAxisNNPtr up = CoordinateSystemAxis::create(
+        util::PropertyMap().set(IdentifiedObject::NAME_KEY,
+                                AxisName::Ellipsoidal_height),
+        AxisAbbreviation::h, AxisDirection::UP,
+        buildUnit(step, "vunits", "vto_meter"));
+
+    return (!ignoreVUnits && !hasParamValue(step, "geoidgrids") &&
+            (hasParamValue(step, "vunits") || hasParamValue(step, "vto_meter")))
+               ? EllipsoidalCS::create(emptyPropertyMap, axis[0], axis[1], up)
+               : EllipsoidalCS::create(emptyPropertyMap, axis[0], axis[1]);
+}
+
+// ---------------------------------------------------------------------------
+
+static double getNumericValue(const std::string &paramValue,
+                              bool *pHasError = nullptr) {
+    try {
+        double value = c_locale_stod(paramValue);
+        if (pHasError)
+            *pHasError = false;
+        return value;
+    } catch (const std::invalid_argument &) {
+        if (pHasError)
+            *pHasError = true;
+        return 0.0;
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+GeographicCRSNNPtr
+PROJStringParser::Private::buildGeographicCRS(int iStep, int iUnitConvert,
+                                              int iAxisSwap, bool ignoreVUnits,
+                                              bool ignorePROJAxis) {
+    const auto &step = steps_[iStep];
+
+    const bool l_isGeographicStep = isGeographicStep(step.name);
+    const auto &title = l_isGeographicStep ? title_ : emptyString;
+
+    auto datum = buildDatum(step, title);
+
+    auto props = PropertyMap().set(IdentifiedObject::NAME_KEY,
+                                   title.empty() ? "unknown" : title);
+    if (l_isGeographicStep &&
+        (hasParamValue(step, "wktext") ||
+         hasParamValue(step, "lon_wrap") | hasParamValue(step, "geoc") ||
+         getNumericValue(getParamValue(step, "lon_0")) != 0.0)) {
+        props.set("EXTENSION_PROJ4", projString_);
+    }
+
+    return GeographicCRS::create(
+        props, datum, buildEllipsoidalCS(iStep, iUnitConvert, iAxisSwap,
+                                         ignoreVUnits, ignorePROJAxis));
+}
+
+// ---------------------------------------------------------------------------
+
+GeodeticCRSNNPtr
+PROJStringParser::Private::buildGeocentricCRS(int iStep, int iUnitConvert) {
+    const auto &step = steps_[iStep];
+
+    assert(isGeocentricStep(step.name));
+    assert(iUnitConvert < 0 ||
+           ci_equal(steps_[iUnitConvert].name, "unitconvert"));
+
+    const auto &title = title_;
+
+    auto datum = buildDatum(step, title);
+
+    UnitOfMeasure unit = UnitOfMeasure::METRE;
+    if (iUnitConvert >= 0) {
+        const auto &stepUnitConvert = steps_[iUnitConvert];
+        const std::string *xy_in = &getParamValue(stepUnitConvert, "xy_in");
+        const std::string *xy_out = &getParamValue(stepUnitConvert, "xy_out");
+        const std::string *z_in = &getParamValue(stepUnitConvert, "z_in");
+        const std::string *z_out = &getParamValue(stepUnitConvert, "z_out");
+        if (stepUnitConvert.inverted) {
+            std::swap(xy_in, xy_out);
+            std::swap(z_in, z_out);
+        }
+        if (xy_in->empty() || xy_out->empty() || *xy_in != "m" ||
+            *z_in != "m" || *xy_out != *z_out) {
+            throw ParsingException(
+                "unhandled values for xy_in, z_in, xy_out or z_out");
+        }
+
+        const LinearUnitDesc *unitsMatch = nullptr;
+        try {
+            double to_meter_value = c_locale_stod(*xy_out);
+            unitsMatch = getLinearUnits(to_meter_value);
+            if (unitsMatch == nullptr) {
+                unit = _buildUnit(to_meter_value);
+            }
+        } catch (const std::invalid_argument &) {
+            unitsMatch = getLinearUnits(*xy_out);
+            if (!unitsMatch) {
+                throw ParsingException(
+                    "unhandled values for xy_in, z_in, xy_out or z_out");
+            }
+            unit = _buildUnit(unitsMatch);
+        }
+    }
+
+    auto props = PropertyMap().set(IdentifiedObject::NAME_KEY,
+                                   title.empty() ? "unknown" : title);
+    if (hasParamValue(step, "wktext")) {
+        props.set("EXTENSION_PROJ4", projString_);
+    }
+
+    auto cs = CartesianCS::createGeocentric(unit);
+    return GeodeticCRS::create(props, datum, cs);
+}
+
+// ---------------------------------------------------------------------------
+
+CRSNNPtr
+PROJStringParser::Private::buildBoundOrCompoundCRSIfNeeded(int iStep,
+                                                           CRSNNPtr crs) {
+    const auto &step = steps_[iStep];
+    const auto &towgs84 = getParamValue(step, "towgs84");
+    if (!towgs84.empty()) {
+        std::vector<double> towgs84Values;
+        const auto tokens = split(towgs84, ',');
+        for (const auto &str : tokens) {
+            try {
+                towgs84Values.push_back(c_locale_stod(str));
+            } catch (const std::invalid_argument &) {
+                throw ParsingException("Non numerical value in towgs84 clause");
+            }
+        }
+        crs = BoundCRS::createFromTOWGS84(crs, towgs84Values);
+    }
+
+    const auto &nadgrids = getParamValue(step, "nadgrids");
+    if (!nadgrids.empty()) {
+        crs = BoundCRS::createFromNadgrids(crs, nadgrids);
+    }
+
+    const auto &geoidgrids = getParamValue(step, "geoidgrids");
+    if (!geoidgrids.empty()) {
+        auto vdatum =
+            VerticalReferenceFrame::create(createMapWithUnknownName());
+
+        const UnitOfMeasure unit = buildUnit(step, "vunits", "vto_meter");
+
+        auto vcrs =
+            VerticalCRS::create(createMapWithUnknownName(), vdatum,
+                                VerticalCS::createGravityRelatedHeight(unit));
+
+        auto transformation =
+            Transformation::createGravityRelatedHeightToGeographic3D(
+                PropertyMap().set(IdentifiedObject::NAME_KEY,
+                                  "unknown to WGS84 ellipsoidal height"),
+                crs, GeographicCRS::EPSG_4979, geoidgrids,
+                std::vector<PositionalAccuracyNNPtr>());
+        auto boundvcrs =
+            BoundCRS::create(vcrs, GeographicCRS::EPSG_4979, transformation);
+
+        crs = CompoundCRS::create(createMapWithUnknownName(),
+                                  std::vector<CRSNNPtr>{crs, boundvcrs});
+    }
+
+    return crs;
+}
+
+// ---------------------------------------------------------------------------
+
+static double getAngularValue(const std::string &paramValue,
+                              bool *pHasError = nullptr) {
+    char *endptr = nullptr;
+    double value = dmstor(paramValue.c_str(), &endptr) * RAD_TO_DEG;
+    if (value == HUGE_VAL || endptr != paramValue.c_str() + paramValue.size()) {
+        if (pHasError)
+            *pHasError = true;
+        return 0.0;
+    }
+    if (pHasError)
+        *pHasError = false;
+    return value;
+}
+
+// ---------------------------------------------------------------------------
+
+CRSNNPtr PROJStringParser::Private::buildProjectedCRS(
+    int iStep, GeographicCRSNNPtr geogCRS, int iUnitConvert, int iAxisSwap) {
+    auto &step = steps_[iStep];
+    auto mappings = getMappingsFromPROJName(step.name);
+    const MethodMapping *mapping = mappings.empty() ? nullptr : mappings[0];
+
+    assert(isProjectedStep(step.name));
+    assert(iUnitConvert < 0 ||
+           ci_equal(steps_[iUnitConvert].name, "unitconvert"));
+
+    const auto &title = title_;
+
+    if (!buildPrimeMeridian(step)->longitude()._isEquivalentTo(
+            geogCRS->primeMeridian()->longitude(),
+            util::IComparable::Criterion::EQUIVALENT)) {
+        throw ParsingException("inconsistent pm values between projectedCRS "
+                               "and its base geographicalCRS");
+    }
+
+    auto axisType = AxisType::REGULAR;
+
+    if (step.name == "tmerc" &&
+        ((getParamValue(step, "axis") == "wsu" && iAxisSwap < 0) ||
+         (iAxisSwap > 0 &&
+          getParamValue(steps_[iAxisSwap], "order") == "-1,-2"))) {
+        mapping =
+            getMapping(EPSG_CODE_METHOD_TRANSVERSE_MERCATOR_SOUTH_ORIENTATED);
+    } else if (step.name == "etmerc") {
+        mapping = getMapping(EPSG_CODE_METHOD_TRANSVERSE_MERCATOR);
+    } else if (step.name == "lcc") {
+        const auto &lat_0 = getParamValue(step, "lat_0");
+        const auto &lat_1 = getParamValue(step, "lat_1");
+        const auto &lat_2 = getParamValue(step, "lat_2");
+        const auto &k = getParamValueK(step);
+        if (lat_2.empty() && !lat_0.empty() && !lat_1.empty() &&
+            getAngularValue(lat_0) == getAngularValue(lat_1)) {
+            mapping = getMapping(EPSG_CODE_METHOD_LAMBERT_CONIC_CONFORMAL_1SP);
+        } else if (!k.empty() && getNumericValue(k) != 1.0) {
+            mapping = getMapping(
+                EPSG_CODE_METHOD_LAMBERT_CONIC_CONFORMAL_2SP_MICHIGAN);
+        } else {
+            mapping = getMapping(EPSG_CODE_METHOD_LAMBERT_CONIC_CONFORMAL_2SP);
+        }
+    } else if (step.name == "aeqd" && hasParamValue(step, "guam")) {
+        mapping = getMapping(EPSG_CODE_METHOD_GUAM_PROJECTION);
+    } else if (step.name == "cea" && !geogCRS->ellipsoid()->isSphere()) {
+        mapping = getMapping(EPSG_CODE_METHOD_LAMBERT_CYLINDRICAL_EQUAL_AREA);
+    } else if (step.name == "geos" && getParamValue(step, "sweep") == "x") {
+        mapping =
+            getMapping(PROJ_WKT2_NAME_METHOD_GEOSTATIONARY_SATELLITE_SWEEP_X);
+    } else if (step.name == "geos") {
+        mapping =
+            getMapping(PROJ_WKT2_NAME_METHOD_GEOSTATIONARY_SATELLITE_SWEEP_Y);
+    } else if (step.name == "omerc") {
+        if (hasParamValue(step, "no_rot")) {
+            mapping = nullptr;
+        } else if (hasParamValue(step, "no_uoff") ||
+                   hasParamValue(step, "no_off")) {
+            mapping =
+                getMapping(EPSG_CODE_METHOD_HOTINE_OBLIQUE_MERCATOR_VARIANT_A);
+        } else if (hasParamValue(step, "lat_1") &&
+                   hasParamValue(step, "lon_1") &&
+                   hasParamValue(step, "lat_2") &&
+                   hasParamValue(step, "lon_2")) {
+            mapping = getMapping(
+                PROJ_WKT2_NAME_METHOD_HOTINE_OBLIQUE_MERCATOR_TWO_POINT_NATURAL_ORIGIN);
+        } else {
+            mapping =
+                getMapping(EPSG_CODE_METHOD_HOTINE_OBLIQUE_MERCATOR_VARIANT_B);
+        }
+    } else if (step.name == "somerc") {
+        mapping =
+            getMapping(EPSG_CODE_METHOD_HOTINE_OBLIQUE_MERCATOR_VARIANT_B);
+        step.paramValues.emplace_back(Step::KeyValue("alpha", "90"));
+        step.paramValues.emplace_back(Step::KeyValue("gamma", "90"));
+        step.paramValues.emplace_back(
+            Step::KeyValue("lonc", getParamValue(step, "lon_0")));
+    } else if (step.name == "krovak" &&
+               ((getParamValue(step, "axis") == "swu" && iAxisSwap < 0) ||
+                (iAxisSwap > 0 &&
+                 getParamValue(steps_[iAxisSwap], "order") == "-2,-1"))) {
+        mapping = getMapping(EPSG_CODE_METHOD_KROVAK);
+    } else if (step.name == "merc") {
+        if (hasParamValue(step, "a") && hasParamValue(step, "b") &&
+            getParamValue(step, "a") == getParamValue(step, "b") &&
+            (!hasParamValue(step, "lat_ts") ||
+             getAngularValue(getParamValue(step, "lat_ts")) == 0.0) &&
+            getNumericValue(getParamValueK(step)) == 1.0 &&
+            getParamValue(step, "nadgrids") == "@null") {
+            mapping = getMapping(
+                EPSG_CODE_METHOD_POPULAR_VISUALISATION_PSEUDO_MERCATOR);
+            for (size_t i = 0; i < step.paramValues.size(); ++i) {
+                if (ci_equal(step.paramValues[i].key, "nadgrids")) {
+                    step.paramValues.erase(step.paramValues.begin() + i);
+                    break;
+                }
+            }
+        } else if (hasParamValue(step, "lat_ts")) {
+            mapping = getMapping(EPSG_CODE_METHOD_MERCATOR_VARIANT_B);
+        } else {
+            mapping = getMapping(EPSG_CODE_METHOD_MERCATOR_VARIANT_A);
+        }
+    } else if (step.name == "stere") {
+        if (hasParamValue(step, "lat_0") &&
+            std::fabs(std::fabs(getAngularValue(getParamValue(step, "lat_0"))) -
+                      90.0) < 1e-10) {
+            const double lat_0 = getAngularValue(getParamValue(step, "lat_0"));
+            if (lat_0 > 0) {
+                axisType = AxisType::NORTH_POLE;
+            } else {
+                axisType = AxisType::SOUTH_POLE;
+            }
+            const auto &lat_ts = getParamValue(step, "lat_ts");
+            const auto &k = getParamValueK(step);
+            if (!lat_ts.empty() &&
+                std::fabs(getAngularValue(lat_ts) - lat_0) > 1e-10 &&
+                !k.empty() && std::fabs(getNumericValue(k) - 1) > 1e-10) {
+                throw ParsingException("lat_ts != lat_0 and k != 1 not "
+                                       "supported for Polar Stereographic");
+            }
+            if (!lat_ts.empty() &&
+                (k.empty() || std::fabs(getNumericValue(k) - 1) < 1e-10)) {
+                mapping =
+                    getMapping(EPSG_CODE_METHOD_POLAR_STEREOGRAPHIC_VARIANT_B);
+            } else {
+                mapping =
+                    getMapping(EPSG_CODE_METHOD_POLAR_STEREOGRAPHIC_VARIANT_A);
+            }
+        } else {
+            mapping = getMapping(PROJ_WKT2_NAME_METHOD_STEREOGRAPHIC);
+        }
+    } else if (step.name == "laea") {
+        if (hasParamValue(step, "lat_0") &&
+            std::fabs(std::fabs(getAngularValue(getParamValue(step, "lat_0"))) -
+                      90.0) < 1e-10) {
+            const double lat_0 = getAngularValue(getParamValue(step, "lat_0"));
+            if (lat_0 > 0) {
+                axisType = AxisType::NORTH_POLE;
+            } else {
+                axisType = AxisType::SOUTH_POLE;
+            }
+        }
+        if (geogCRS->ellipsoid()->isSphere()) {
+            mapping = getMapping(
+                EPSG_CODE_METHOD_LAMBERT_AZIMUTHAL_EQUAL_AREA_SPHERICAL);
+        }
+    } else if (step.name == "eqc") {
+        if (geogCRS->ellipsoid()->isSphere()) {
+            mapping =
+                getMapping(EPSG_CODE_METHOD_EQUIDISTANT_CYLINDRICAL_SPHERICAL);
+        }
+    }
+
+    UnitOfMeasure unit = buildUnit(step, "units", "to_meter");
+    if (iUnitConvert >= 0) {
+        const auto &stepUnitConvert = steps_[iUnitConvert];
+        const std::string *xy_in = &getParamValue(stepUnitConvert, "xy_in");
+        const std::string *xy_out = &getParamValue(stepUnitConvert, "xy_out");
+        if (stepUnitConvert.inverted) {
+            std::swap(xy_in, xy_out);
+        }
+        if (xy_in->empty() || xy_out->empty() || *xy_in != "m") {
+            if (step.name != "ob_tran") {
+                throw ParsingException(
+                    "unhandled values for xy_in and/or xy_out");
+            }
+        }
+
+        const LinearUnitDesc *unitsMatch = nullptr;
+        try {
+            double to_meter_value = c_locale_stod(*xy_out);
+            unitsMatch = getLinearUnits(to_meter_value);
+            if (unitsMatch == nullptr) {
+                unit = _buildUnit(to_meter_value);
+            }
+        } catch (const std::invalid_argument &) {
+            unitsMatch = getLinearUnits(*xy_out);
+            if (!unitsMatch) {
+                if (step.name != "ob_tran") {
+                    throw ParsingException(
+                        "unhandled values for xy_in and/or xy_out");
+                }
+            } else {
+                unit = _buildUnit(unitsMatch);
+            }
+        }
+    }
+
+    ConversionPtr conv;
+
+    auto mapWithUnknownName = createMapWithUnknownName();
+
+    if (step.name == "utm") {
+        const int zone = std::atoi(getParamValue(step, "zone").c_str());
+        const bool north = !hasParamValue(step, "south");
+        conv =
+            Conversion::createUTM(emptyPropertyMap, zone, north).as_nullable();
+    } else if (mapping) {
+
+        auto methodMap =
+            PropertyMap().set(IdentifiedObject::NAME_KEY, mapping->wkt2_name);
+        if (mapping->epsg_code) {
+            methodMap.set(Identifier::CODESPACE_KEY, Identifier::EPSG)
+                .set(Identifier::CODE_KEY, mapping->epsg_code);
+        }
+        std::vector<OperationParameterNNPtr> parameters;
+        std::vector<ParameterValueNNPtr> values;
+        for (int i = 0; mapping->params[i] != nullptr; i++) {
+            const auto *param = mapping->params[i];
+            std::string proj_name(param->proj_name ? param->proj_name : "");
+            const std::string *paramValue =
+                (proj_name == "k" || proj_name == "k_0")
+                    ? &getParamValueK(step)
+                    : !proj_name.empty() ? &getParamValue(step, proj_name)
+                                         : &emptyString;
+            double value = 0;
+            if (!paramValue->empty()) {
+                bool hasError = false;
+                if (param->unit_type == UnitOfMeasure::Type::ANGULAR) {
+                    value = getAngularValue(*paramValue, &hasError);
+                } else {
+                    value = getNumericValue(*paramValue, &hasError);
+                }
+                if (hasError) {
+                    throw ParsingException("invalid value for " + proj_name);
+                }
+
+            } else if (param->unit_type == UnitOfMeasure::Type::SCALE) {
+                value = 1;
+            } else {
+                // For omerc, if gamma is missing, the default value is
+                // alpha
+                if (step.name == "omerc" && proj_name == "gamma") {
+                    paramValue = &getParamValue(step, "alpha");
+                    if (!paramValue->empty()) {
+                        value = getAngularValue(*paramValue);
+                    }
+                } else if (step.name == "krovak") {
+                    if (param->epsg_code ==
+                        EPSG_CODE_PARAMETER_COLATITUDE_CONE_AXIS) {
+                        value = 30.28813975277777776;
+                    } else if (
+                        param->epsg_code ==
+                        EPSG_CODE_PARAMETER_LATITUDE_PSEUDO_STANDARD_PARALLEL) {
+                        value = 78.5;
+                    }
+                }
+            }
+
+            PropertyMap propertiesParameter;
+            propertiesParameter.set(IdentifiedObject::NAME_KEY,
+                                    param->wkt2_name);
+            if (param->epsg_code) {
+                propertiesParameter.set(Identifier::CODE_KEY, param->epsg_code);
+                propertiesParameter.set(Identifier::CODESPACE_KEY,
+                                        Identifier::EPSG);
+            }
+            parameters.push_back(
+                OperationParameter::create(propertiesParameter));
+            // In PROJ convention, angular parameters are always in degree
+            // and linear parameters always in metre.
+            double valRounded =
+                param->unit_type == UnitOfMeasure::Type::LINEAR
+                    ? Length(value, UnitOfMeasure::METRE).convertToUnit(unit)
+                    : value;
+            if (std::fabs(valRounded - std::round(valRounded)) < 1e-8) {
+                valRounded = std::round(valRounded);
+            }
+            values.push_back(ParameterValue::create(Measure(
+                valRounded,
+                param->unit_type == UnitOfMeasure::Type::ANGULAR
+                    ? UnitOfMeasure::DEGREE
+                    : param->unit_type == UnitOfMeasure::Type::LINEAR
+                          ? unit
+                          : param->unit_type == UnitOfMeasure::Type::SCALE
+                                ? UnitOfMeasure::SCALE_UNITY
+                                : UnitOfMeasure::NONE)));
+        }
+
+        if (step.name == "etmerc") {
+            methodMap.set("proj_method", "etmerc");
+        }
+
+        conv = Conversion::create(mapWithUnknownName, methodMap, parameters,
+                                  values)
+                   .as_nullable();
+    } else {
+        std::vector<OperationParameterNNPtr> parameters;
+        std::vector<ParameterValueNNPtr> values;
+        std::string methodName = "PROJ " + step.name;
+        for (const auto &param : step.paramValues) {
+            if (param.key == "wktext" || param.key == "no_defs" ||
+                param.key == "datum" || param.key == "ellps" ||
+                param.key == "a" || param.key == "b" || param.key == "R" ||
+                param.key == "towgs84" || param.key == "nadgrids" ||
+                param.key == "geoidgrids" || param.key == "units" ||
+                param.key == "to_meter" || param.key == "vunits" ||
+                param.key == "vto_meter") {
+                continue;
+            }
+            if (param.value.empty()) {
+                methodName += " " + param.key;
+            } else if (param.key == "o_proj") {
+                methodName += " " + param.key + "=" + param.value;
+            } else {
+                parameters.push_back(OperationParameter::create(
+                    PropertyMap().set(IdentifiedObject::NAME_KEY, param.key)));
+                bool hasError = false;
+                if (param.key == "x_0" || param.key == "y_0") {
+                    double value = getNumericValue(param.value, &hasError);
+                    values.push_back(ParameterValue::create(
+                        Measure(value, UnitOfMeasure::METRE)));
+                } else if (param.key == "k" || param.key == "k_0") {
+                    double value = getNumericValue(param.value, &hasError);
+                    values.push_back(ParameterValue::create(
+                        Measure(value, UnitOfMeasure::SCALE_UNITY)));
+                } else {
+                    double value = getAngularValue(param.value, &hasError);
+                    values.push_back(ParameterValue::create(
+                        Measure(value, UnitOfMeasure::DEGREE)));
+                }
+                if (hasError) {
+                    throw ParsingException("invalid value for " + param.key);
+                }
+            }
+        }
+        conv = Conversion::create(
+                   mapWithUnknownName,
+                   PropertyMap().set(IdentifiedObject::NAME_KEY, methodName),
+                   parameters, values)
+                   .as_nullable();
+
+        if (methodName == "PROJ ob_tran o_proj=longlat") {
+            return DerivedGeographicCRS::create(
+                PropertyMap().set(IdentifiedObject::NAME_KEY, "unnamed"),
+                geogCRS, NN_NO_CHECK(conv),
+                buildEllipsoidalCS(iStep, iUnitConvert, iAxisSwap, false,
+                                   false));
+        }
+    }
+
+    std::vector<CoordinateSystemAxisNNPtr> axis =
+        processAxisSwap(step, unit, iAxisSwap, axisType, false);
+
+    auto cs = CartesianCS::create(emptyPropertyMap, axis[0], axis[1]);
+
+    auto props = PropertyMap().set(IdentifiedObject::NAME_KEY,
+                                   title.empty() ? "unknown" : title);
+
+    if (hasParamValue(step, "wktext")) {
+        props.set("EXTENSION_PROJ4", projString_);
+    }
+
+    CRSNNPtr crs = ProjectedCRS::create(props, geogCRS, NN_NO_CHECK(conv), cs);
+
+    if (!hasParamValue(step, "geoidgrids") &&
+        (hasParamValue(step, "vunits") || hasParamValue(step, "vto_meter"))) {
+        auto vdatum = VerticalReferenceFrame::create(mapWithUnknownName);
+
+        const UnitOfMeasure vunit = buildUnit(step, "vunits", "vto_meter");
+
+        auto vcrs =
+            VerticalCRS::create(mapWithUnknownName, vdatum,
+                                VerticalCS::createGravityRelatedHeight(vunit));
+
+        crs = CompoundCRS::create(mapWithUnknownName,
+                                  std::vector<CRSNNPtr>{crs, vcrs});
+    }
+
+    return crs;
+}
+
+// ---------------------------------------------------------------------------
+
+static bool isDatumDefiningParam(const std::string &param) {
+    return (param == "datum" || param == "ellps" || param == "a" ||
+            param == "b" || param == "rf" || param == "f" || param == "R");
+}
+
+// ---------------------------------------------------------------------------
+
+CoordinateOperationNNPtr PROJStringParser::Private::buildHelmertTransformation(
+    int iStep, int iFirstAxisSwap, int iFirstUnitConvert, int iFirstGeogStep,
+    int iSecondGeogStep, int iSecondAxisSwap, int iSecondUnitConvert) {
+    auto &step = steps_[iStep];
+    auto datum = buildDatum(step, std::string());
+    auto cs = CartesianCS::createGeocentric(UnitOfMeasure::METRE);
+
+    auto mapWithUnknownName = createMapWithUnknownName();
+
+    auto sourceCRS =
+        iFirstGeogStep >= 0
+            ? util::nn_static_pointer_cast<crs::CRS>(
+                  buildGeographicCRS(iFirstGeogStep, iFirstUnitConvert,
+                                     iFirstAxisSwap, true, false))
+            : util::nn_static_pointer_cast<crs::CRS>(
+                  GeodeticCRS::create(mapWithUnknownName, datum, cs));
+    auto targetCRS =
+        iSecondGeogStep >= 0
+            ? util::nn_static_pointer_cast<crs::CRS>(
+                  buildGeographicCRS(iSecondGeogStep, iSecondUnitConvert,
+                                     iSecondAxisSwap, true, false))
+            : util::nn_static_pointer_cast<crs::CRS>(
+                  GeodeticCRS::create(mapWithUnknownName, datum, cs));
+
+    double x = 0;
+    double y = 0;
+    double z = 0;
+    double rx = 0;
+    double ry = 0;
+    double rz = 0;
+    double s = 0;
+    double dx = 0;
+    double dy = 0;
+    double dz = 0;
+    double drx = 0;
+    double dry = 0;
+    double drz = 0;
+    double ds = 0;
+    double t_epoch = 0;
+    bool rotationTerms = false;
+    bool timeDependent = false;
+    bool conventionFound = false;
+    bool positionVectorConvention = false;
+
+    struct Params {
+        double *pValue;
+        const char *name;
+        bool *pPresent;
+    };
+    const Params knownParams[] = {
+        {&x, "x", nullptr},
+        {&y, "y", nullptr},
+        {&z, "z", nullptr},
+        {&rx, "rx", &rotationTerms},
+        {&ry, "ry", &rotationTerms},
+        {&rz, "rz", &rotationTerms},
+        {&s, "s", &rotationTerms},
+        {&dx, "dx", &timeDependent},
+        {&dy, "dy", &timeDependent},
+        {&dz, "dz", &timeDependent},
+        {&drx, "drx", &timeDependent},
+        {&dry, "dry", &timeDependent},
+        {&drz, "drz", &timeDependent},
+        {&ds, "ds", &timeDependent},
+        {&t_epoch, "t_epoch", &timeDependent},
+        {nullptr, "exact", nullptr},
+    };
+
+    for (const auto &param : step.paramValues) {
+        if (isDatumDefiningParam(param.key)) {
+            continue;
+        }
+        if (param.key == "convention") {
+            if (param.value == "position_vector") {
+                positionVectorConvention = true;
+                conventionFound = true;
+            } else if (param.value == "coordinate_frame") {
+                positionVectorConvention = false;
+                conventionFound = true;
+            } else {
+                throw ParsingException("unsupported convention");
+            }
+        } else {
+            bool found = false;
+            for (auto &&knownParam : knownParams) {
+                if (param.key == knownParam.name) {
+                    found = true;
+                    if (knownParam.pValue)
+                        *(knownParam.pValue) = getNumericValue(param.value);
+                    if (knownParam.pPresent)
+                        *(knownParam.pPresent) = true;
+                    break;
+                }
+            }
+            if (!found) {
+                throw ParsingException("unsupported keyword for Helmert: " +
+                                       param.key);
+            }
+        }
+    }
+
+    rotationTerms |= timeDependent;
+    if (rotationTerms && !conventionFound) {
+        throw ParsingException("missing convention");
+    }
+
+    std::vector<metadata::PositionalAccuracyNNPtr> emptyAccuracies;
+
+    auto transf = ([&]() {
+        if (!rotationTerms) {
+            return Transformation::createGeocentricTranslations(
+                mapWithUnknownName, sourceCRS, targetCRS, x, y, z,
+                emptyAccuracies);
+        } else if (positionVectorConvention) {
+            if (timeDependent) {
+                return Transformation::createTimeDependentPositionVector(
+                    mapWithUnknownName, sourceCRS, targetCRS, x, y, z, rx, ry,
+                    rz, s, dx, dy, dz, drx, dry, drz, ds, t_epoch,
+                    emptyAccuracies);
+            } else {
+                return Transformation::createPositionVector(
+                    mapWithUnknownName, sourceCRS, targetCRS, x, y, z, rx, ry,
+                    rz, s, emptyAccuracies);
+            }
+        } else {
+            if (timeDependent) {
+                return Transformation::
+                    createTimeDependentCoordinateFrameRotation(
+                        mapWithUnknownName, sourceCRS, targetCRS, x, y, z, rx,
+                        ry, rz, s, dx, dy, dz, drx, dry, drz, ds, t_epoch,
+                        emptyAccuracies);
+            } else {
+                return Transformation::createCoordinateFrameRotation(
+                    mapWithUnknownName, sourceCRS, targetCRS, x, y, z, rx, ry,
+                    rz, s, emptyAccuracies);
+            }
+        }
+    })();
+
+    if (step.inverted) {
+        return util::nn_static_pointer_cast<CoordinateOperation>(
+            transf->inverse());
+    } else {
+        return util::nn_static_pointer_cast<CoordinateOperation>(transf);
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+CoordinateOperationNNPtr
+PROJStringParser::Private::buildMolodenskyTransformation(
+    int iStep, int iFirstAxisSwap, int iFirstUnitConvert, int iFirstGeogStep,
+    int iSecondGeogStep, int iSecondAxisSwap, int iSecondUnitConvert) {
+    auto &step = steps_[iStep];
+
+    double dx = 0;
+    double dy = 0;
+    double dz = 0;
+    double da = 0;
+    double df = 0;
+
+    struct Params {
+        double *pValue;
+        const char *name;
+    };
+    const Params knownParams[] = {
+        {&dx, "dx"}, {&dy, "dy"}, {&dz, "dz"}, {&da, "da"}, {&df, "df"},
+    };
+    bool abridged = false;
+
+    for (const auto &param : step.paramValues) {
+        if (isDatumDefiningParam(param.key)) {
+            continue;
+        } else if (param.key == "abridged") {
+            abridged = true;
+        } else {
+            bool found = false;
+            for (auto &&knownParam : knownParams) {
+                if (param.key == knownParam.name) {
+                    found = true;
+                    if (knownParam.pValue)
+                        *(knownParam.pValue) = getNumericValue(param.value);
+                    break;
+                }
+            }
+            if (!found) {
+                throw ParsingException("unsupported keyword for Molodensky: " +
+                                       param.key);
+            }
+        }
+    }
+
+    auto datum = buildDatum(step, std::string());
+    auto sourceCRS = iFirstGeogStep >= 0
+                         ? buildGeographicCRS(iFirstGeogStep, iFirstUnitConvert,
+                                              iFirstAxisSwap, true, false)
+                         : buildGeographicCRS(iStep, -1, -1, true, false);
+
+    const auto &ellps = sourceCRS->ellipsoid();
+    const double a = ellps->semiMajorAxis().getSIValue();
+    const double rf = ellps->computedInverseFlattening();
+    const double target_a = a + da;
+    const double target_rf = 1.0 / (1.0 / rf + df);
+
+    auto mapWithUnknownName = createMapWithUnknownName();
+
+    auto target_ellipsoid =
+        Ellipsoid::createFlattenedSphere(mapWithUnknownName, Length(target_a),
+                                         Scale(target_rf))
+            ->identify();
+    auto target_datum = GeodeticReferenceFrame::create(
+        mapWithUnknownName, target_ellipsoid, util::optional<std::string>(),
+        PrimeMeridian::GREENWICH);
+
+    auto targetCRS = util::nn_static_pointer_cast<crs::CRS>(
+        iSecondGeogStep >= 0
+            ? buildGeographicCRS(iSecondGeogStep, iSecondUnitConvert,
+                                 iSecondAxisSwap, true, false)
+            : GeographicCRS::create(mapWithUnknownName, target_datum,
+                                    EllipsoidalCS::createLongitudeLatitude(
+                                        UnitOfMeasure::DEGREE)));
+
+    auto sourceCRS_as_CRS = util::nn_static_pointer_cast<crs::CRS>(sourceCRS);
+
+    std::vector<metadata::PositionalAccuracyNNPtr> emptyAccuracies;
+
+    auto transf = ([&]() {
+        if (abridged) {
+            return Transformation::createAbridgedMolodensky(
+                mapWithUnknownName, sourceCRS_as_CRS, targetCRS, dx, dy, dz, da,
+                df, emptyAccuracies);
+        } else {
+            return Transformation::createMolodensky(
+                mapWithUnknownName, sourceCRS_as_CRS, targetCRS, dx, dy, dz, da,
+                df, emptyAccuracies);
+        }
+    })();
+
+    if (step.inverted) {
+        return util::nn_static_pointer_cast<CoordinateOperation>(
+            transf->inverse());
+    } else {
+        return util::nn_static_pointer_cast<CoordinateOperation>(transf);
+    }
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static const metadata::ExtentPtr nullExtent{};
+
+static const metadata::ExtentPtr &getExtent(const crs::CRS *crs) {
+    const auto &domains = crs->domains();
+    if (!domains.empty()) {
+        return domains[0]->domainOfValidity();
+    }
+    return nullExtent;
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a sub-class of BaseObject from a PROJ string.
+ * @throw ParsingException
+ */
+BaseObjectNNPtr
+PROJStringParser::createFromPROJString(const std::string &projString) {
+    std::string vunits;
+    std::string vto_meter;
+
+    d->steps_.clear();
+    d->title_.clear();
+    d->globalParamValues_.clear();
+    d->projString_ = projString;
+    PROJStringSyntaxParser(projString, d->steps_, d->globalParamValues_,
+                           d->title_, vunits, vto_meter);
+
+    if (d->steps_.empty()) {
+
+        if (!vunits.empty() || !vto_meter.empty()) {
+            Step fakeStep;
+            if (!vunits.empty()) {
+                fakeStep.paramValues.emplace_back(
+                    Step::KeyValue("vunits", vunits));
+            }
+            if (!vto_meter.empty()) {
+                fakeStep.paramValues.emplace_back(
+                    Step::KeyValue("vto_meter", vto_meter));
+            }
+            auto vdatum =
+                VerticalReferenceFrame::create(createMapWithUnknownName());
+            auto vcrs = VerticalCRS::create(
+                createMapWithUnknownName(), vdatum,
+                VerticalCS::createGravityRelatedHeight(
+                    d->buildUnit(fakeStep, "vunits", "vto_meter")));
+            return vcrs;
+        }
+    }
+
+    if ((d->steps_.size() == 1 ||
+         (d->steps_.size() == 2 && d->steps_[1].name == "unitconvert")) &&
+        isGeocentricStep(d->steps_[0].name)) {
+        return d->buildBoundOrCompoundCRSIfNeeded(
+            0, d->buildGeocentricCRS(0, (d->steps_.size() == 2 &&
+                                         d->steps_[1].name == "unitconvert")
+                                            ? 1
+                                            : -1));
+    }
+
+    // +init=xxxx:yyyy syntax
+    if (d->steps_.size() == 1 && d->steps_[0].isInit &&
+        d->steps_[0].paramValues.size() == 0) {
+
+        // Those used to come from a text init file
+        // We only support them in compatibility mode
+        const std::string &stepName = d->steps_[0].name;
+        if (ci_starts_with(stepName, "epsg:") ||
+            ci_starts_with(stepName, "IGNF:")) {
+            bool usePROJ4InitRules = d->usePROJ4InitRules_;
+            if (!usePROJ4InitRules) {
+                PJ_CONTEXT *ctx = proj_context_create();
+                if (ctx) {
+                    usePROJ4InitRules = proj_context_get_use_proj4_init_rules(
+                                            ctx, FALSE) == TRUE;
+                    proj_context_destroy(ctx);
+                }
+            }
+            if (!usePROJ4InitRules) {
+                throw ParsingException("init=epsg:/init=IGNF: syntax not "
+                                       "supported in non-PROJ4 emulation mode");
+            }
+
+            PJ_CONTEXT *ctx = proj_context_create();
+            char unused[256];
+            std::string initname(stepName);
+            initname.resize(initname.find(':'));
+            int file_found =
+                pj_find_file(ctx, initname.c_str(), unused, sizeof(unused));
+            proj_context_destroy(ctx);
+            if (!file_found) {
+                auto obj = createFromUserInput(stepName, d->dbContext_, true);
+                auto crs = dynamic_cast<CRS *>(obj.get());
+                if (crs) {
+                    PropertyMap properties;
+                    properties.set(IdentifiedObject::NAME_KEY, crs->nameStr());
+                    const auto &extent = getExtent(crs);
+                    if (extent) {
+                        properties.set(
+                            common::ObjectUsage::DOMAIN_OF_VALIDITY_KEY,
+                            NN_NO_CHECK(extent));
+                    }
+                    auto geogCRS = dynamic_cast<GeographicCRS *>(crs);
+                    if (geogCRS) {
+                        // Override with longitude latitude in radian
+                        return GeographicCRS::create(
+                            properties, geogCRS->datum(),
+                            geogCRS->datumEnsemble(),
+                            EllipsoidalCS::createLongitudeLatitude(
+                                UnitOfMeasure::RADIAN));
+                    }
+                    auto projCRS = dynamic_cast<ProjectedCRS *>(crs);
+                    if (projCRS) {
+                        // Override with easting northing order
+                        const auto &conv = projCRS->derivingConversionRef();
+                        if (conv->method()->getEPSGCode() !=
+                            EPSG_CODE_METHOD_TRANSVERSE_MERCATOR_SOUTH_ORIENTATED) {
+                            return ProjectedCRS::create(
+                                properties, projCRS->baseCRS(), conv,
+                                CartesianCS::createEastingNorthing(
+                                    projCRS->coordinateSystem()
+                                        ->axisList()[0]
+                                        ->unit()));
+                        }
+                    }
+                }
+                return obj;
+            }
+        }
+
+        paralist *init = pj_mkparam(("init=" + d->steps_[0].name).c_str());
+        if (!init) {
+            throw ParsingException("out of memory");
+        }
+        PJ_CONTEXT *ctx = proj_context_create();
+        if (!ctx) {
+            pj_dealloc(init);
+            throw ParsingException("out of memory");
+        }
+        paralist *list = pj_expand_init(ctx, init);
+        proj_context_destroy(ctx);
+        if (!list) {
+            pj_dealloc(init);
+            throw ParsingException("cannot expand " + projString);
+        }
+        std::string expanded;
+        bool first = true;
+        bool has_init_term = false;
+        for (auto t = list; t;) {
+            if (!expanded.empty()) {
+                expanded += ' ';
+            }
+            if (first) {
+                // first parameter is the init= itself
+                first = false;
+            } else if (starts_with(t->param, "init=")) {
+                has_init_term = true;
+            } else {
+                expanded += t->param;
+            }
+
+            auto n = t->next;
+            pj_dealloc(t);
+            t = n;
+        }
+
+        if (!has_init_term) {
+            return createFromPROJString(expanded);
+        }
+    }
+
+    int iFirstGeogStep = -1;
+    int iSecondGeogStep = -1;
+    int iProjStep = -1;
+    int iFirstUnitConvert = -1;
+    int iSecondUnitConvert = -1;
+    int iFirstAxisSwap = -1;
+    int iSecondAxisSwap = -1;
+    int iHelmert = -1;
+    int iFirstCart = -1;
+    int iSecondCart = -1;
+    int iMolodensky = -1;
+    bool unexpectedStructure = false;
+    for (int i = 0; i < static_cast<int>(d->steps_.size()); i++) {
+        const auto &stepName = d->steps_[i].name;
+        if (isGeographicStep(stepName)) {
+            if (iFirstGeogStep < 0) {
+                iFirstGeogStep = i;
+            } else if (iSecondGeogStep < 0) {
+                iSecondGeogStep = i;
+            } else {
+                unexpectedStructure = true;
+                break;
+            }
+        } else if (ci_equal(stepName, "unitconvert")) {
+            if (iFirstUnitConvert < 0) {
+                iFirstUnitConvert = i;
+            } else if (iSecondUnitConvert < 0) {
+                iSecondUnitConvert = i;
+            } else {
+                unexpectedStructure = true;
+                break;
+            }
+        } else if (ci_equal(stepName, "axisswap")) {
+            if (iFirstAxisSwap < 0) {
+                iFirstAxisSwap = i;
+            } else if (iSecondAxisSwap < 0) {
+                iSecondAxisSwap = i;
+            } else {
+                unexpectedStructure = true;
+                break;
+            }
+        } else if (stepName == "helmert") {
+            if (iHelmert >= 0) {
+                unexpectedStructure = true;
+                break;
+            }
+            iHelmert = i;
+        } else if (stepName == "cart") {
+            if (iFirstCart < 0) {
+                iFirstCart = i;
+            } else if (iSecondCart < 0) {
+                iSecondCart = i;
+            } else {
+                unexpectedStructure = true;
+                break;
+            }
+        } else if (stepName == "molodensky") {
+            if (iMolodensky >= 0) {
+                unexpectedStructure = true;
+                break;
+            }
+            iMolodensky = i;
+        } else if (isProjectedStep(stepName)) {
+            if (iProjStep >= 0) {
+                unexpectedStructure = true;
+                break;
+            }
+            iProjStep = i;
+        } else {
+            unexpectedStructure = true;
+            break;
+        }
+    }
+
+    if (!unexpectedStructure) {
+        if (iFirstGeogStep == 0 && iSecondGeogStep < 0 && iProjStep < 0 &&
+            iHelmert < 0 && iFirstCart < 0 && iMolodensky < 0 &&
+            (iFirstUnitConvert < 0 || iSecondUnitConvert < 0) &&
+            (iFirstAxisSwap < 0 || iSecondAxisSwap < 0)) {
+            const bool ignoreVUnits = false;
+            return d->buildBoundOrCompoundCRSIfNeeded(
+                0, d->buildGeographicCRS(iFirstGeogStep, iFirstUnitConvert,
+                                         iFirstAxisSwap, ignoreVUnits, false));
+        }
+        if (iProjStep >= 0 && !d->steps_[iProjStep].inverted &&
+            (iFirstGeogStep < 0 || iFirstGeogStep + 1 == iProjStep) &&
+            iMolodensky < 0 && iSecondGeogStep < 0 && iFirstCart < 0 &&
+            iHelmert < 0) {
+            if (iFirstGeogStep < 0)
+                iFirstGeogStep = iProjStep;
+            const bool ignoreVUnits = true;
+            return d->buildBoundOrCompoundCRSIfNeeded(
+                iProjStep,
+                d->buildProjectedCRS(
+                    iProjStep,
+                    d->buildGeographicCRS(
+                        iFirstGeogStep,
+                        iFirstUnitConvert < iFirstGeogStep ? iFirstUnitConvert
+                                                           : -1,
+                        iFirstAxisSwap < iFirstGeogStep ? iFirstAxisSwap : -1,
+                        ignoreVUnits, true),
+                    iFirstUnitConvert < iFirstGeogStep ? iSecondUnitConvert
+                                                       : iFirstUnitConvert,
+                    iFirstAxisSwap < iFirstGeogStep ? iSecondAxisSwap
+                                                    : iFirstAxisSwap));
+        }
+        if (d->steps_.size() == 1 && iHelmert == 0) {
+            return d->buildHelmertTransformation(iHelmert);
+        }
+
+        if (iProjStep < 0 && iHelmert > 0 && iMolodensky < 0 &&
+            (iFirstGeogStep < 0 || iFirstGeogStep == iFirstCart - 1 ||
+             (iFirstGeogStep == iSecondCart + 1 && iSecondGeogStep < 0)) &&
+            iFirstCart == iHelmert - 1 && iSecondCart == iHelmert + 1 &&
+            (iSecondGeogStep < 0 || iSecondGeogStep == iSecondCart + 1) &&
+            !d->steps_[iFirstCart].inverted &&
+            d->steps_[iSecondCart].inverted && iFirstAxisSwap < iHelmert &&
+            iFirstUnitConvert < iHelmert &&
+            (iSecondAxisSwap < 0 || iSecondAxisSwap > iHelmert) &&
+            (iSecondUnitConvert < 0 || iSecondUnitConvert > iHelmert)) {
+            return d->buildHelmertTransformation(
+                iHelmert, iFirstAxisSwap, iFirstUnitConvert,
+                iFirstGeogStep >= 0 && iFirstGeogStep == iFirstCart - 1
+                    ? iFirstGeogStep
+                    : iFirstCart,
+                iFirstGeogStep == iSecondCart + 1
+                    ? iFirstGeogStep
+                    : iSecondGeogStep == iSecondCart + 1 ? iSecondGeogStep
+                                                         : iSecondCart,
+                iSecondAxisSwap, iSecondUnitConvert);
+        }
+
+        if (d->steps_.size() == 1 && iMolodensky == 0) {
+            return d->buildMolodenskyTransformation(iMolodensky);
+        }
+
+        if (iProjStep < 0 && iHelmert < 0 && iMolodensky > 0 &&
+            (iFirstGeogStep < 0 || iFirstGeogStep == iMolodensky - 1 ||
+             (iFirstGeogStep == iMolodensky + 1 && iSecondGeogStep < 0)) &&
+            (iSecondGeogStep < 0 || iSecondGeogStep == iMolodensky + 1) &&
+            iFirstAxisSwap < iMolodensky && iFirstUnitConvert < iMolodensky &&
+            (iSecondAxisSwap < 0 || iSecondAxisSwap > iMolodensky) &&
+            (iSecondUnitConvert < 0 || iSecondUnitConvert > iMolodensky)) {
+            return d->buildMolodenskyTransformation(
+                iMolodensky, iFirstAxisSwap, iFirstUnitConvert,
+                iFirstGeogStep >= 0 && iFirstGeogStep == iMolodensky - 1
+                    ? iFirstGeogStep
+                    : iMolodensky,
+                iFirstGeogStep == iMolodensky + 1
+                    ? iFirstGeogStep
+                    : iSecondGeogStep == iMolodensky + 1 ? iSecondGeogStep
+                                                         : iMolodensky,
+                iSecondAxisSwap, iSecondUnitConvert);
+        }
+    }
+
+    struct Logger {
+        std::string msg{};
+
+        // cppcheck-suppress functionStatic
+        void setMessage(const char *msgIn) noexcept {
+            try {
+                msg = msgIn;
+            } catch (const std::exception &) {
+            }
+        }
+
+        static void log(void *user_data, int level, const char *msg) {
+            if (level == PJ_LOG_ERROR) {
+                static_cast<Logger *>(user_data)->setMessage(msg);
+            }
+        }
+    };
+
+    // If the structure is not recognized, then try to instanciate the
+    // pipeline, and if successful, wrap it in a PROJBasedOperation
+    Logger logger;
+    auto pj_context = proj_context_create();
+    if (!pj_context) {
+        throw ParsingException("out of memory");
+    }
+    proj_log_func(pj_context, &logger, Logger::log);
+    proj_context_use_proj4_init_rules(pj_context, d->usePROJ4InitRules_);
+    auto pj = proj_create(pj_context, projString.c_str());
+    bool valid = pj != nullptr;
+    proj_destroy(pj);
+
+    if (!valid && logger.msg.empty()) {
+        logger.setMessage(proj_errno_string(proj_context_errno(pj_context)));
+    }
+
+    proj_context_destroy(pj_context);
+
+    if (!valid) {
+        throw ParsingException(logger.msg);
+    }
+
+    auto props = PropertyMap();
+    if (!d->title_.empty()) {
+        props.set(IdentifiedObject::NAME_KEY, d->title_);
+    }
+    return operation::SingleOperation::createPROJBased(props, projString,
+                                                       nullptr, nullptr, {});
+}
+
+} // namespace io
+NS_PROJ_END
diff --git a/src/iso19111/metadata.cpp b/src/iso19111/metadata.cpp
new file mode 100644
index 00000000..2be9dac3
--- /dev/null
+++ b/src/iso19111/metadata.cpp
@@ -0,0 +1,1285 @@
+/******************************************************************************
+ *
+ * Project:  PROJ
+ * Purpose:  ISO19111:2018 implementation
+ * Author:   Even Rouault <even dot rouault at spatialys dot com>
+ *
+ ******************************************************************************
+ * Copyright (c) 2018, Even Rouault <even dot rouault at spatialys dot com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ ****************************************************************************/
+
+#ifndef FROM_PROJ_CPP
+#define FROM_PROJ_CPP
+#endif
+
+#include "proj/metadata.hpp"
+#include "proj/common.hpp"
+#include "proj/io.hpp"
+#include "proj/util.hpp"
+
+#include "proj/internal/internal.hpp"
+#include "proj/internal/io_internal.hpp"
+
+#include <algorithm>
+#include <memory>
+#include <string>
+#include <vector>
+
+using namespace NS_PROJ::internal;
+using namespace NS_PROJ::io;
+using namespace NS_PROJ::util;
+
+#if 0
+namespace dropbox{ namespace oxygen {
+template<> nn<std::shared_ptr<NS_PROJ::metadata::Citation>>::~nn() = default;
+template<> nn<NS_PROJ::metadata::ExtentPtr>::~nn() = default;
+template<> nn<NS_PROJ::metadata::GeographicBoundingBoxPtr>::~nn() = default;
+template<> nn<NS_PROJ::metadata::GeographicExtentPtr>::~nn() = default;
+template<> nn<NS_PROJ::metadata::VerticalExtentPtr>::~nn() = default;
+template<> nn<NS_PROJ::metadata::TemporalExtentPtr>::~nn() = default;
+template<> nn<NS_PROJ::metadata::IdentifierPtr>::~nn() = default;
+template<> nn<NS_PROJ::metadata::PositionalAccuracyPtr>::~nn() = default;
+}}
+#endif
+
+NS_PROJ_START
+namespace metadata {
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct Citation::Private {
+    optional<std::string> title{};
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+Citation::Citation() : d(internal::make_unique<Private>()) {}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Constructs a citation by its title. */
+Citation::Citation(const std::string &titleIn)
+    : d(internal::make_unique<Private>()) {
+    d->title = titleIn;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+Citation::Citation(const Citation &other)
+    : d(internal::make_unique<Private>(*(other.d))) {}
+
+// ---------------------------------------------------------------------------
+
+Citation::~Citation() = default;
+
+// ---------------------------------------------------------------------------
+
+Citation &Citation::operator=(const Citation &other) {
+    if (this != &other) {
+        *d = *other.d;
+    }
+    return *this;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns the name by which the cited resource is known. */
+const optional<std::string> &Citation::title() PROJ_CONST_DEFN {
+    return d->title;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct GeographicExtent::Private {};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+GeographicExtent::GeographicExtent() : d(internal::make_unique<Private>()) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+GeographicExtent::~GeographicExtent() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct GeographicBoundingBox::Private {
+    double west_{};
+    double south_{};
+    double east_{};
+    double north_{};
+
+    Private(double west, double south, double east, double north)
+        : west_(west), south_(south), east_(east), north_(north) {}
+
+    bool intersects(const Private &other) const;
+
+    std::unique_ptr<Private> intersection(const Private &other) const;
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+GeographicBoundingBox::GeographicBoundingBox(double west, double south,
+                                             double east, double north)
+    : GeographicExtent(),
+      d(internal::make_unique<Private>(west, south, east, north)) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+GeographicBoundingBox::~GeographicBoundingBox() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns the western-most coordinate of the limit of the dataset
+ * extent.
+ *
+ * The unit is degrees.
+ *
+ * If eastBoundLongitude < westBoundLongitude(), then the bounding box crosses
+ * the anti-meridian.
+ */
+double GeographicBoundingBox::westBoundLongitude() PROJ_CONST_DEFN {
+    return d->west_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns the southern-most coordinate of the limit of the dataset
+ * extent.
+ *
+ * The unit is degrees.
+ */
+double GeographicBoundingBox::southBoundLatitude() PROJ_CONST_DEFN {
+    return d->south_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns the eastern-most coordinate of the limit of the dataset
+ * extent.
+ *
+ * The unit is degrees.
+ *
+ * If eastBoundLongitude < westBoundLongitude(), then the bounding box crosses
+ * the anti-meridian.
+ */
+double GeographicBoundingBox::eastBoundLongitude() PROJ_CONST_DEFN {
+    return d->east_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns the northern-most coordinate of the limit of the dataset
+ * extent.
+ *
+ * The unit is degrees.
+ */
+double GeographicBoundingBox::northBoundLatitude() PROJ_CONST_DEFN {
+    return d->north_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a GeographicBoundingBox.
+ *
+ * If east < west, then the bounding box crosses the anti-meridian.
+ *
+ * @param west Western-most coordinate of the limit of the dataset extent (in
+ * degrees).
+ * @param south Southern-most coordinate of the limit of the dataset extent (in
+ * degrees).
+ * @param east Eastern-most coordinate of the limit of the dataset extent (in
+ * degrees).
+ * @param north Northern-most coordinate of the limit of the dataset extent (in
+ * degrees).
+ * @return a new GeographicBoundingBox.
+ */
+GeographicBoundingBoxNNPtr GeographicBoundingBox::create(double west,
+                                                         double south,
+                                                         double east,
+                                                         double north) {
+    return GeographicBoundingBox::nn_make_shared<GeographicBoundingBox>(
+        west, south, east, north);
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+bool GeographicBoundingBox::_isEquivalentTo(
+    const util::IComparable *other, util::IComparable::Criterion) const {
+    auto otherExtent = dynamic_cast<const GeographicBoundingBox *>(other);
+    if (!otherExtent)
+        return false;
+    return d->west_ == otherExtent->d->west_ &&
+           d->south_ == otherExtent->d->south_ &&
+           d->east_ == otherExtent->d->east_ &&
+           d->north_ == otherExtent->d->north_;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+bool GeographicBoundingBox::contains(const GeographicExtentNNPtr &other) const {
+    auto otherExtent = dynamic_cast<const GeographicBoundingBox *>(other.get());
+    if (!otherExtent) {
+        return false;
+    }
+    const double W = d->west_;
+    const double E = d->east_;
+    const double N = d->north_;
+    const double S = d->south_;
+    const double oW = otherExtent->d->west_;
+    const double oE = otherExtent->d->east_;
+    const double oN = otherExtent->d->north_;
+    const double oS = otherExtent->d->south_;
+
+    if (!(S <= oS && N >= oN)) {
+        return false;
+    }
+
+    if (W == -180.0 && E == 180.0) {
+        return true;
+    }
+
+    if (oW == -180.0 && oE == 180.0) {
+        return false;
+    }
+
+    // Normal bounding box ?
+    if (W < E) {
+        if (oW < oE) {
+            return W <= oW && E >= oE;
+        } else {
+            return false;
+        }
+        // No: crossing antimerian
+    } else {
+        if (oW < oE) {
+            if (oW >= W) {
+                return true;
+            } else if (oE <= E) {
+                return true;
+            } else {
+                return false;
+            }
+        } else {
+            return W <= oW && E >= oE;
+        }
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+bool GeographicBoundingBox::Private::intersects(const Private &other) const {
+    const double W = west_;
+    const double E = east_;
+    const double N = north_;
+    const double S = south_;
+    const double oW = other.west_;
+    const double oE = other.east_;
+    const double oN = other.north_;
+    const double oS = other.south_;
+
+    if (N < oS || S > oN) {
+        return false;
+    }
+
+    if (W == -180.0 && E == 180.0 && oW > oE) {
+        return true;
+    }
+
+    if (oW == -180.0 && oE == 180.0 && W > E) {
+        return true;
+    }
+
+    // Normal bounding box ?
+    if (W <= E) {
+        if (oW < oE) {
+            if (std::max(W, oW) < std::min(E, oE)) {
+                return true;
+            }
+            return false;
+        }
+
+        return intersects(Private(oW, oS, 180.0, oN)) ||
+               intersects(Private(-180.0, oS, oE, oN));
+
+        // No: crossing antimerian
+    } else {
+        if (oW <= oE) {
+            return other.intersects(*this);
+        }
+
+        return true;
+    }
+}
+//! @endcond
+
+bool GeographicBoundingBox::intersects(
+    const GeographicExtentNNPtr &other) const {
+    auto otherExtent = dynamic_cast<const GeographicBoundingBox *>(other.get());
+    if (!otherExtent) {
+        return false;
+    }
+    return d->intersects(*(otherExtent->d));
+}
+
+// ---------------------------------------------------------------------------
+
+GeographicExtentPtr
+GeographicBoundingBox::intersection(const GeographicExtentNNPtr &other) const {
+    auto otherExtent = dynamic_cast<const GeographicBoundingBox *>(other.get());
+    if (!otherExtent) {
+        return nullptr;
+    }
+    auto ret = d->intersection(*(otherExtent->d));
+    if (ret) {
+        auto bbox = GeographicBoundingBox::create(ret->west_, ret->south_,
+                                                  ret->east_, ret->north_);
+        return bbox.as_nullable();
+    }
+    return nullptr;
+}
+
+//! @cond Doxygen_Suppress
+std::unique_ptr<GeographicBoundingBox::Private>
+GeographicBoundingBox::Private::intersection(const Private &otherExtent) const {
+    const double W = west_;
+    const double E = east_;
+    const double N = north_;
+    const double S = south_;
+    const double oW = otherExtent.west_;
+    const double oE = otherExtent.east_;
+    const double oN = otherExtent.north_;
+    const double oS = otherExtent.south_;
+
+    if (N < oS || S > oN) {
+        return nullptr;
+    }
+
+    if (W == -180.0 && E == 180.0 && oW > oE) {
+        return internal::make_unique<Private>(oW, std::max(S, oS), oE,
+                                              std::min(N, oN));
+    }
+
+    if (oW == -180.0 && oE == 180.0 && W > E) {
+        return internal::make_unique<Private>(W, std::max(S, oS), E,
+                                              std::min(N, oN));
+    }
+
+    // Normal bounding box ?
+    if (W <= E) {
+        if (oW < oE) {
+            auto res = internal::make_unique<Private>(
+                std::max(W, oW), std::max(S, oS), std::min(E, oE),
+                std::min(N, oN));
+            if (res->west_ < res->east_) {
+                return res;
+            }
+            return nullptr;
+        }
+
+        // Return larger of two parts of the multipolygon
+        auto inter1 = intersection(Private(oW, oS, 180.0, oN));
+        auto inter2 = intersection(Private(-180.0, oS, oE, oN));
+        if (!inter1) {
+            return inter2;
+        }
+        if (!inter2) {
+            return inter1;
+        }
+        if (inter1->east_ - inter1->west_ > inter2->east_ - inter2->west_) {
+            return inter1;
+        }
+        return inter2;
+        // No: crossing antimerian
+    } else {
+        if (oW <= oE) {
+            return otherExtent.intersection(*this);
+        }
+
+        return internal::make_unique<Private>(std::max(W, oW), std::max(S, oS),
+                                              std::min(E, oE), std::min(N, oN));
+    }
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct VerticalExtent::Private {
+    double minimum_{};
+    double maximum_{};
+    common::UnitOfMeasureNNPtr unit_;
+
+    Private(double minimum, double maximum,
+            const common::UnitOfMeasureNNPtr &unit)
+        : minimum_(minimum), maximum_(maximum), unit_(unit) {}
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+VerticalExtent::VerticalExtent(double minimumIn, double maximumIn,
+                               const common::UnitOfMeasureNNPtr &unitIn)
+    : d(internal::make_unique<Private>(minimumIn, maximumIn, unitIn)) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+VerticalExtent::~VerticalExtent() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns the minimum of the vertical extent.
+ */
+double VerticalExtent::minimumValue() PROJ_CONST_DEFN { return d->minimum_; }
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns the maximum of the vertical extent.
+ */
+double VerticalExtent::maximumValue() PROJ_CONST_DEFN { return d->maximum_; }
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns the unit of the vertical extent.
+ */
+common::UnitOfMeasureNNPtr &VerticalExtent::unit() PROJ_CONST_DEFN {
+    return d->unit_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a VerticalExtent.
+ *
+ * @param minimumIn minimum.
+ * @param maximumIn maximum.
+ * @param unitIn unit.
+ * @return a new VerticalExtent.
+ */
+VerticalExtentNNPtr
+VerticalExtent::create(double minimumIn, double maximumIn,
+                       const common::UnitOfMeasureNNPtr &unitIn) {
+    return VerticalExtent::nn_make_shared<VerticalExtent>(minimumIn, maximumIn,
+                                                          unitIn);
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+bool VerticalExtent::_isEquivalentTo(const util::IComparable *other,
+                                     util::IComparable::Criterion) const {
+    auto otherExtent = dynamic_cast<const VerticalExtent *>(other);
+    if (!otherExtent)
+        return false;
+    return d->minimum_ == otherExtent->d->minimum_ &&
+           d->maximum_ == otherExtent->d->maximum_ &&
+           d->unit_ == otherExtent->d->unit_;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns whether this extent contains the other one.
+ */
+bool VerticalExtent::contains(const VerticalExtentNNPtr &other) const {
+    const double thisUnitToSI = d->unit_->conversionToSI();
+    const double otherUnitToSI = other->d->unit_->conversionToSI();
+    return d->minimum_ * thisUnitToSI <= other->d->minimum_ * otherUnitToSI &&
+           d->maximum_ * thisUnitToSI >= other->d->maximum_ * otherUnitToSI;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns whether this extent intersects the other one.
+ */
+bool VerticalExtent::intersects(const VerticalExtentNNPtr &other) const {
+    const double thisUnitToSI = d->unit_->conversionToSI();
+    const double otherUnitToSI = other->d->unit_->conversionToSI();
+    return d->minimum_ * thisUnitToSI <= other->d->maximum_ * otherUnitToSI &&
+           d->maximum_ * thisUnitToSI >= other->d->minimum_ * otherUnitToSI;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct TemporalExtent::Private {
+    std::string start_{};
+    std::string stop_{};
+
+    Private(const std::string &start, const std::string &stop)
+        : start_(start), stop_(stop) {}
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+TemporalExtent::TemporalExtent(const std::string &startIn,
+                               const std::string &stopIn)
+    : d(internal::make_unique<Private>(startIn, stopIn)) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+TemporalExtent::~TemporalExtent() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns the start of the temporal extent.
+ */
+const std::string &TemporalExtent::start() PROJ_CONST_DEFN { return d->start_; }
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns the end of the temporal extent.
+ */
+const std::string &TemporalExtent::stop() PROJ_CONST_DEFN { return d->stop_; }
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a TemporalExtent.
+ *
+ * @param start start.
+ * @param stop stop.
+ * @return a new TemporalExtent.
+ */
+TemporalExtentNNPtr TemporalExtent::create(const std::string &start,
+                                           const std::string &stop) {
+    return TemporalExtent::nn_make_shared<TemporalExtent>(start, stop);
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+bool TemporalExtent::_isEquivalentTo(const util::IComparable *other,
+                                     util::IComparable::Criterion) const {
+    auto otherExtent = dynamic_cast<const TemporalExtent *>(other);
+    if (!otherExtent)
+        return false;
+    return start() == otherExtent->start() && stop() == otherExtent->stop();
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns whether this extent contains the other one.
+ */
+bool TemporalExtent::contains(const TemporalExtentNNPtr &other) const {
+    return start() <= other->start() && stop() >= other->stop();
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns whether this extent intersects the other one.
+ */
+bool TemporalExtent::intersects(const TemporalExtentNNPtr &other) const {
+    return start() <= other->stop() && stop() >= other->start();
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct Extent::Private {
+    optional<std::string> description_{};
+    std::vector<GeographicExtentNNPtr> geographicElements_{};
+    std::vector<VerticalExtentNNPtr> verticalElements_{};
+    std::vector<TemporalExtentNNPtr> temporalElements_{};
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+Extent::Extent() : d(internal::make_unique<Private>()) {}
+
+// ---------------------------------------------------------------------------
+
+Extent::Extent(const Extent &other)
+    : d(internal::make_unique<Private>(*other.d)) {}
+
+// ---------------------------------------------------------------------------
+
+Extent::~Extent() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** Return a textual description of the extent.
+ *
+ * @return the description, or empty.
+ */
+const optional<std::string> &Extent::description() PROJ_CONST_DEFN {
+    return d->description_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** Return the geographic element(s) of the extent
+ *
+ * @return the geographic element(s), or empty.
+ */
+const std::vector<GeographicExtentNNPtr> &
+Extent::geographicElements() PROJ_CONST_DEFN {
+    return d->geographicElements_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** Return the vertical element(s) of the extent
+ *
+ * @return the vertical element(s), or empty.
+ */
+const std::vector<VerticalExtentNNPtr> &
+Extent::verticalElements() PROJ_CONST_DEFN {
+    return d->verticalElements_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** Return the temporal element(s) of the extent
+ *
+ * @return the temporal element(s), or empty.
+ */
+const std::vector<TemporalExtentNNPtr> &
+Extent::temporalElements() PROJ_CONST_DEFN {
+    return d->temporalElements_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a Extent.
+ *
+ * @param descriptionIn Textual description, or empty.
+ * @param geographicElementsIn Geographic element(s), or empty.
+ * @param verticalElementsIn Vertical element(s), or empty.
+ * @param temporalElementsIn Temporal element(s), or empty.
+ * @return a new Extent.
+ */
+ExtentNNPtr
+Extent::create(const optional<std::string> &descriptionIn,
+               const std::vector<GeographicExtentNNPtr> &geographicElementsIn,
+               const std::vector<VerticalExtentNNPtr> &verticalElementsIn,
+               const std::vector<TemporalExtentNNPtr> &temporalElementsIn) {
+    auto extent = Extent::nn_make_shared<Extent>();
+    extent->assignSelf(extent);
+    extent->d->description_ = descriptionIn;
+    extent->d->geographicElements_ = geographicElementsIn;
+    extent->d->verticalElements_ = verticalElementsIn;
+    extent->d->temporalElements_ = temporalElementsIn;
+    return extent;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a Extent from a bounding box
+ *
+ * @param west Western-most coordinate of the limit of the dataset extent (in
+ * degrees).
+ * @param south Southern-most coordinate of the limit of the dataset extent (in
+ * degrees).
+ * @param east Eastern-most coordinate of the limit of the dataset extent (in
+ * degrees).
+ * @param north Northern-most coordinate of the limit of the dataset extent (in
+ * degrees).
+ * @param descriptionIn Textual description, or empty.
+ * @return a new Extent.
+ */
+ExtentNNPtr
+Extent::createFromBBOX(double west, double south, double east, double north,
+                       const util::optional<std::string> &descriptionIn) {
+    return create(
+        descriptionIn,
+        std::vector<GeographicExtentNNPtr>{
+            nn_static_pointer_cast<GeographicExtent>(
+                GeographicBoundingBox::create(west, south, east, north))},
+        std::vector<VerticalExtentNNPtr>(), std::vector<TemporalExtentNNPtr>());
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+bool Extent::_isEquivalentTo(const util::IComparable *other,
+                             util::IComparable::Criterion criterion) const {
+    auto otherExtent = dynamic_cast<const Extent *>(other);
+    bool ret =
+        (otherExtent &&
+         description().has_value() == otherExtent->description().has_value() &&
+         *description() == *otherExtent->description() &&
+         d->geographicElements_.size() ==
+             otherExtent->d->geographicElements_.size() &&
+         d->verticalElements_.size() ==
+             otherExtent->d->verticalElements_.size() &&
+         d->temporalElements_.size() ==
+             otherExtent->d->temporalElements_.size());
+    if (ret) {
+        for (size_t i = 0; ret && i < d->geographicElements_.size(); ++i) {
+            ret = d->geographicElements_[i]->_isEquivalentTo(
+                otherExtent->d->geographicElements_[i].get(), criterion);
+        }
+        for (size_t i = 0; ret && i < d->verticalElements_.size(); ++i) {
+            ret = d->verticalElements_[i]->_isEquivalentTo(
+                otherExtent->d->verticalElements_[i].get(), criterion);
+        }
+        for (size_t i = 0; ret && i < d->temporalElements_.size(); ++i) {
+            ret = d->temporalElements_[i]->_isEquivalentTo(
+                otherExtent->d->temporalElements_[i].get(), criterion);
+        }
+    }
+    return ret;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns whether this extent contains the other one.
+ *
+ * Behaviour only well specified if each sub-extent category as at most
+ * one element.
+ */
+bool Extent::contains(const ExtentNNPtr &other) const {
+    bool res = true;
+    if (d->geographicElements_.size() == 1 &&
+        other->d->geographicElements_.size() == 1) {
+        res = d->geographicElements_[0]->contains(
+            other->d->geographicElements_[0]);
+    }
+    if (res && d->verticalElements_.size() == 1 &&
+        other->d->verticalElements_.size() == 1) {
+        res = d->verticalElements_[0]->contains(other->d->verticalElements_[0]);
+    }
+    if (res && d->temporalElements_.size() == 1 &&
+        other->d->temporalElements_.size() == 1) {
+        res = d->temporalElements_[0]->contains(other->d->temporalElements_[0]);
+    }
+    return res;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns whether this extent intersects the other one.
+ *
+ * Behaviour only well specified if each sub-extent category as at most
+ * one element.
+ */
+bool Extent::intersects(const ExtentNNPtr &other) const {
+    bool res = true;
+    if (d->geographicElements_.size() == 1 &&
+        other->d->geographicElements_.size() == 1) {
+        res = d->geographicElements_[0]->intersects(
+            other->d->geographicElements_[0]);
+    }
+    if (res && d->verticalElements_.size() == 1 &&
+        other->d->verticalElements_.size() == 1) {
+        res =
+            d->verticalElements_[0]->intersects(other->d->verticalElements_[0]);
+    }
+    if (res && d->temporalElements_.size() == 1 &&
+        other->d->temporalElements_.size() == 1) {
+        res =
+            d->temporalElements_[0]->intersects(other->d->temporalElements_[0]);
+    }
+    return res;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns the intersection of this extent with another one.
+ *
+ * Behaviour only well specified if there is one single GeographicExtent
+ * in each object.
+ * Returns nullptr otherwise.
+ */
+ExtentPtr Extent::intersection(const ExtentNNPtr &other) const {
+    if (d->geographicElements_.size() == 1 &&
+        other->d->geographicElements_.size() == 1) {
+        if (contains(other)) {
+            return other.as_nullable();
+        }
+        auto self = util::nn_static_pointer_cast<Extent>(shared_from_this());
+        if (other->contains(self)) {
+            return self.as_nullable();
+        }
+        auto geogIntersection = d->geographicElements_[0]->intersection(
+            other->d->geographicElements_[0]);
+        if (geogIntersection) {
+            return create(util::optional<std::string>(),
+                          std::vector<GeographicExtentNNPtr>{
+                              NN_NO_CHECK(geogIntersection)},
+                          std::vector<VerticalExtentNNPtr>{},
+                          std::vector<TemporalExtentNNPtr>{});
+        }
+    }
+    return nullptr;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct Identifier::Private {
+    optional<Citation> authority_{};
+    std::string code_{};
+    optional<std::string> codeSpace_{};
+    optional<std::string> version_{};
+    optional<std::string> description_{};
+    optional<std::string> uri_{};
+
+    Private() = default;
+
+    Private(const std::string &codeIn, const PropertyMap &properties)
+        : code_(codeIn) {
+        setProperties(properties);
+    }
+
+  private:
+    // cppcheck-suppress functionStatic
+    void setProperties(const PropertyMap &properties);
+};
+
+// ---------------------------------------------------------------------------
+
+void Identifier::Private::setProperties(
+    const PropertyMap &properties) // throw(InvalidValueTypeException)
+{
+    {
+        const auto pVal = properties.get(AUTHORITY_KEY);
+        if (pVal) {
+            if (auto genVal = dynamic_cast<const BoxedValue *>(pVal->get())) {
+                if (genVal->type() == BoxedValue::Type::STRING) {
+                    authority_ = Citation(genVal->stringValue());
+                } else {
+                    throw InvalidValueTypeException("Invalid value type for " +
+                                                    AUTHORITY_KEY);
+                }
+            } else {
+                if (auto citation =
+                        dynamic_cast<const Citation *>(pVal->get())) {
+                    authority_ = *citation;
+                } else {
+                    throw InvalidValueTypeException("Invalid value type for " +
+                                                    AUTHORITY_KEY);
+                }
+            }
+        }
+    }
+
+    {
+        const auto pVal = properties.get(CODE_KEY);
+        if (pVal) {
+            if (auto genVal = dynamic_cast<const BoxedValue *>(pVal->get())) {
+                if (genVal->type() == BoxedValue::Type::INTEGER) {
+                    code_ = toString(genVal->integerValue());
+                } else if (genVal->type() == BoxedValue::Type::STRING) {
+                    code_ = genVal->stringValue();
+                } else {
+                    throw InvalidValueTypeException("Invalid value type for " +
+                                                    CODE_KEY);
+                }
+            } else {
+                throw InvalidValueTypeException("Invalid value type for " +
+                                                CODE_KEY);
+            }
+        }
+    }
+
+    properties.getStringValue(CODESPACE_KEY, codeSpace_);
+    properties.getStringValue(VERSION_KEY, version_);
+    properties.getStringValue(DESCRIPTION_KEY, description_);
+    properties.getStringValue(URI_KEY, uri_);
+}
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+Identifier::Identifier(const std::string &codeIn,
+                       const util::PropertyMap &properties)
+    : d(internal::make_unique<Private>(codeIn, properties)) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+// ---------------------------------------------------------------------------
+
+Identifier::Identifier() : d(internal::make_unique<Private>()) {}
+
+// ---------------------------------------------------------------------------
+
+Identifier::Identifier(const Identifier &other)
+    : d(internal::make_unique<Private>(*(other.d))) {}
+
+// ---------------------------------------------------------------------------
+
+Identifier::~Identifier() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a Identifier.
+ *
+ * @param codeIn Alphanumeric value identifying an instance in the codespace
+ * @param properties See \ref general_properties.
+ * Generally, the Identifier::CODESPACE_KEY should be set.
+ * @return a new Identifier.
+ */
+IdentifierNNPtr Identifier::create(const std::string &codeIn,
+                                   const PropertyMap &properties) {
+    return Identifier::nn_make_shared<Identifier>(codeIn, properties);
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+IdentifierNNPtr
+Identifier::createFromDescription(const std::string &descriptionIn) {
+    auto id = Identifier::nn_make_shared<Identifier>();
+    id->d->description_ = descriptionIn;
+    return id;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return a citation for the organization responsible for definition and
+ * maintenance of the code.
+ *
+ * @return the citation for the authority, or empty.
+ */
+const optional<Citation> &Identifier::authority() PROJ_CONST_DEFN {
+    return d->authority_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the alphanumeric value identifying an instance in the
+ * codespace.
+ *
+ * e.g. "4326" (for EPSG:4326 WGS 84 GeographicCRS)
+ *
+ * @return the code.
+ */
+const std::string &Identifier::code() PROJ_CONST_DEFN { return d->code_; }
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the organization responsible for definition and maintenance of
+ * the code.
+ *
+ * e.g "EPSG"
+ *
+ * @return the authority codespace, or empty.
+ */
+const optional<std::string> &Identifier::codeSpace() PROJ_CONST_DEFN {
+    return d->codeSpace_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the version identifier for the namespace.
+ *
+ * When appropriate, the edition is identified by the effective date, coded
+ * using ISO 8601 date format.
+ *
+ * @return the version or empty.
+ */
+const optional<std::string> &Identifier::version() PROJ_CONST_DEFN {
+    return d->version_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the natural language description of the meaning of the code
+ * value.
+ *
+ * @return the description or empty.
+ */
+const optional<std::string> &Identifier::description() PROJ_CONST_DEFN {
+    return d->description_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the URI of the identifier.
+ *
+ * @return the URI or empty.
+ */
+const optional<std::string> &Identifier::uri() PROJ_CONST_DEFN {
+    return d->uri_;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+void Identifier::_exportToWKT(WKTFormatter *formatter) const {
+    const bool isWKT2 = formatter->version() == WKTFormatter::Version::WKT2;
+    const std::string &l_code = code();
+    const std::string &l_codeSpace = *codeSpace();
+    if (!l_codeSpace.empty() && !l_code.empty()) {
+        if (isWKT2) {
+            formatter->startNode(WKTConstants::ID, false);
+            formatter->addQuotedString(l_codeSpace);
+            try {
+                (void)std::stoi(l_code);
+                formatter->add(l_code);
+            } catch (const std::exception &) {
+                formatter->addQuotedString(l_code);
+            }
+            if (version().has_value()) {
+                auto l_version = *(version());
+                try {
+                    (void)c_locale_stod(l_version);
+                    formatter->add(l_version);
+                } catch (const std::exception &) {
+                    formatter->addQuotedString(l_version);
+                }
+            }
+            if (authority().has_value() &&
+                *(authority()->title()) != l_codeSpace) {
+                formatter->startNode(WKTConstants::CITATION, false);
+                formatter->addQuotedString(*(authority()->title()));
+                formatter->endNode();
+            }
+            if (uri().has_value()) {
+                formatter->startNode(WKTConstants::URI, false);
+                formatter->addQuotedString(*(uri()));
+                formatter->endNode();
+            }
+            formatter->endNode();
+        } else {
+            formatter->startNode(WKTConstants::AUTHORITY, false);
+            formatter->addQuotedString(l_codeSpace);
+            formatter->addQuotedString(l_code);
+            formatter->endNode();
+        }
+    }
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static bool isIgnoredChar(char ch) {
+    return ch == ' ' || ch == '_' || ch == '-' || ch == '/' || ch == '(' ||
+           ch == ')' || ch == '.' || ch == '&';
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+static const struct utf8_to_lower {
+    const char *utf8;
+    char ascii;
+} map_utf8_to_lower[] = {
+    {"\xc3\xa1", 'a'}, // a acute
+    {"\xc3\xa4", 'a'}, // a tremma
+
+    {"\xc4\x9b", 'e'}, // e reverse circumflex
+    {"\xc3\xa8", 'e'}, // e grave
+    {"\xc3\xa9", 'e'}, // e acute
+    {"\xc3\xab", 'e'}, // e tremma
+
+    {"\xc3\xad", 'i'}, // i grave
+
+    {"\xc3\xb4", 'o'}, // o circumflex
+    {"\xc3\xb6", 'o'}, // o tremma
+
+    {"\xc3\xa7", 'c'}, // c cedilla
+};
+
+static const struct utf8_to_lower *get_ascii_replacement(const char *c_str) {
+    for (const auto &pair : map_utf8_to_lower) {
+        if (*c_str == pair.utf8[0] &&
+            strncmp(c_str, pair.utf8, strlen(pair.utf8)) == 0) {
+            return &pair;
+        }
+    }
+    return nullptr;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+std::string Identifier::canonicalizeName(const std::string &str) {
+    std::string res;
+    const char *c_str = str.c_str();
+    for (size_t i = 0; c_str[i] != 0; ++i) {
+        const auto ch = c_str[i];
+        if (ch == ' ' && c_str[i + 1] == '+' && c_str[i + 2] == ' ') {
+            i += 2;
+            continue;
+        }
+        if (ch == '1' && !res.empty() &&
+            !(res.back() >= '0' && res.back() <= '9') && c_str[i + 1] == '9' &&
+            c_str[i + 2] >= '0' && c_str[i + 2] <= '9') {
+            ++i;
+            continue;
+        }
+        if (static_cast<unsigned char>(ch) > 127) {
+            const auto *replacement = get_ascii_replacement(c_str + i);
+            if (replacement) {
+                res.push_back(replacement->ascii);
+                i += strlen(replacement->utf8) - 1;
+                continue;
+            }
+        }
+        if (!isIgnoredChar(ch)) {
+            res.push_back(static_cast<char>(::tolower(ch)));
+        }
+    }
+    return res;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns whether two names are considered equivalent.
+ *
+ * Two names are equivalent by removing any space, underscore, dash, slash,
+ * { or } character from them, and comparing in a case insensitive way.
+ */
+bool Identifier::isEquivalentName(const char *a, const char *b) noexcept {
+    size_t i = 0;
+    size_t j = 0;
+    char lastValidA = 0;
+    char lastValidB = 0;
+    while (a[i] != 0 && b[j] != 0) {
+        char aCh = a[i];
+        char bCh = b[j];
+        if (aCh == ' ' && a[i + 1] == '+' && a[i + 2] == ' ') {
+            i += 3;
+            continue;
+        }
+        if (bCh == ' ' && b[j + 1] == '+' && b[j + 2] == ' ') {
+            j += 3;
+            continue;
+        }
+        if (isIgnoredChar(aCh)) {
+            ++i;
+            continue;
+        }
+        if (isIgnoredChar(bCh)) {
+            ++j;
+            continue;
+        }
+        if (aCh == '1' && !(lastValidA >= '0' && lastValidA <= '9') &&
+            a[i + 1] == '9' && a[i + 2] >= '0' && a[i + 2] <= '9') {
+            i += 2;
+            lastValidA = '9';
+            continue;
+        }
+        if (bCh == '1' && !(lastValidB >= '0' && lastValidB <= '9') &&
+            b[j + 1] == '9' && b[j + 2] >= '0' && b[j + 2] <= '9') {
+            j += 2;
+            lastValidB = '9';
+            continue;
+        }
+        if (static_cast<unsigned char>(aCh) > 127) {
+            const auto *replacement = get_ascii_replacement(a + i);
+            if (replacement) {
+                aCh = replacement->ascii;
+                i += strlen(replacement->utf8) - 1;
+            }
+        }
+        if (static_cast<unsigned char>(bCh) > 127) {
+            const auto *replacement = get_ascii_replacement(b + j);
+            if (replacement) {
+                bCh = replacement->ascii;
+                j += strlen(replacement->utf8) - 1;
+            }
+        }
+        if (::tolower(aCh) != ::tolower(bCh)) {
+            return false;
+        }
+        lastValidA = aCh;
+        lastValidB = bCh;
+        ++i;
+        ++j;
+    }
+    while (a[i] != 0 && isIgnoredChar(a[i])) {
+        ++i;
+    }
+    while (b[j] != 0 && isIgnoredChar(b[j])) {
+        ++j;
+    }
+    return a[i] == b[j];
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct PositionalAccuracy::Private {
+    std::string value_{};
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+PositionalAccuracy::PositionalAccuracy(const std::string &valueIn)
+    : d(internal::make_unique<Private>()) {
+    d->value_ = valueIn;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+PositionalAccuracy::~PositionalAccuracy() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Return the value of the positional accuracy.
+ */
+const std::string &PositionalAccuracy::value() PROJ_CONST_DEFN {
+    return d->value_;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a PositionalAccuracy.
+ *
+ * @param valueIn positional accuracy value.
+ * @return a new PositionalAccuracy.
+ */
+PositionalAccuracyNNPtr PositionalAccuracy::create(const std::string &valueIn) {
+    return PositionalAccuracy::nn_make_shared<PositionalAccuracy>(valueIn);
+}
+
+} // namespace metadata
+NS_PROJ_END
diff --git a/src/iso19111/static.cpp b/src/iso19111/static.cpp
new file mode 100644
index 00000000..5de046f1
--- /dev/null
+++ b/src/iso19111/static.cpp
@@ -0,0 +1,644 @@
+/******************************************************************************
+ *
+ * Project:  PROJ
+ * Purpose:  ISO19111:2018 implementation
+ * Author:   Even Rouault <even dot rouault at spatialys dot com>
+ *
+ ******************************************************************************
+ * Copyright (c) 2018, Even Rouault <even dot rouault at spatialys dot com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ ****************************************************************************/
+
+#ifndef FROM_PROJ_CPP
+#define FROM_PROJ_CPP
+#endif
+
+#include "proj/common.hpp"
+#include "proj/coordinatesystem.hpp"
+#include "proj/crs.hpp"
+#include "proj/datum.hpp"
+#include "proj/io.hpp"
+#include "proj/metadata.hpp"
+#include "proj/util.hpp"
+
+#include "proj/internal/coordinatesystem_internal.hpp"
+#include "proj/internal/io_internal.hpp"
+
+#include <map>
+#include <set>
+#include <string>
+
+#ifndef M_PI
+#define M_PI 3.14159265358979323846
+#endif
+
+// We put all static definitions in the same compilation unit, and in
+// increasing order of dependency, to avoid the "static initialization fiasco"
+// See https://isocpp.org/wiki/faq/ctors#static-init-order
+
+using namespace NS_PROJ::crs;
+using namespace NS_PROJ::datum;
+using namespace NS_PROJ::io;
+using namespace NS_PROJ::metadata;
+using namespace NS_PROJ::util;
+
+NS_PROJ_START
+
+// ---------------------------------------------------------------------------
+
+/** \brief Key to set the authority citation of a metadata::Identifier.
+ *
+ * The value is to be provided as a string or a metadata::Citation.
+ */
+const std::string Identifier::AUTHORITY_KEY("authority");
+
+/** \brief Key to set the code of a metadata::Identifier.
+ *
+ * The value is to be provided as a integer or a string.
+ */
+const std::string Identifier::CODE_KEY("code");
+
+/** \brief Key to set the organization responsible for definition and
+ * maintenance of the code of a metadata::Identifier.
+ *
+ * The value is to be provided as a string.
+ */
+const std::string Identifier::CODESPACE_KEY("codespace");
+
+/** \brief Key to set the version identifier for the namespace of a
+ * metadata::Identifier.
+ *
+ * The value is to be provided as a string.
+ */
+const std::string Identifier::VERSION_KEY("version");
+
+/** \brief Key to set the natural language description of the meaning of the
+ * code value of a metadata::Identifier.
+ *
+ * The value is to be provided as a string.
+ */
+const std::string Identifier::DESCRIPTION_KEY("description");
+
+/** \brief Key to set the URI of a metadata::Identifier.
+ *
+ * The value is to be provided as a string.
+ */
+const std::string Identifier::URI_KEY("uri");
+
+/** \brief EPSG codespace.
+ */
+const std::string Identifier::EPSG("EPSG");
+
+/** \brief OGC codespace.
+ */
+const std::string Identifier::OGC("OGC");
+
+// ---------------------------------------------------------------------------
+
+/** \brief Key to set the name of a common::IdentifiedObject
+ *
+ * The value is to be provided as a string or metadata::IdentifierNNPtr.
+ */
+const std::string common::IdentifiedObject::NAME_KEY("name");
+
+/** \brief Key to set the identifier(s) of a common::IdentifiedObject
+ *
+ * The value is to be provided as a common::IdentifierNNPtr or a
+ * util::ArrayOfBaseObjectNNPtr
+ * of common::IdentifierNNPtr.
+ */
+const std::string common::IdentifiedObject::IDENTIFIERS_KEY("identifiers");
+
+/** \brief Key to set the alias(es) of a common::IdentifiedObject
+ *
+ * The value is to be provided as string, a util::GenericNameNNPtr or a
+ * util::ArrayOfBaseObjectNNPtr
+ * of util::GenericNameNNPtr.
+ */
+const std::string common::IdentifiedObject::ALIAS_KEY("alias");
+
+/** \brief Key to set the remarks of a common::IdentifiedObject
+ *
+ * The value is to be provided as a string.
+ */
+const std::string common::IdentifiedObject::REMARKS_KEY("remarks");
+
+/** \brief Key to set the deprecation flag of a common::IdentifiedObject
+ *
+ * The value is to be provided as a boolean.
+ */
+const std::string common::IdentifiedObject::DEPRECATED_KEY("deprecated");
+
+// ---------------------------------------------------------------------------
+
+/** \brief Key to set the scope of a common::ObjectUsage
+ *
+ * The value is to be provided as a string.
+ */
+const std::string common::ObjectUsage::SCOPE_KEY("scope");
+
+/** \brief Key to set the domain of validity of a common::ObjectUsage
+ *
+ * The value is to be provided as a common::ExtentNNPtr.
+ */
+const std::string
+    common::ObjectUsage::DOMAIN_OF_VALIDITY_KEY("domainOfValidity");
+
+/** \brief Key to set the object domain(s) of a common::ObjectUsage
+ *
+ * The value is to be provided as a common::ObjectDomainNNPtr or a
+ * util::ArrayOfBaseObjectNNPtr
+ * of common::ObjectDomainNNPtr.
+ */
+const std::string common::ObjectUsage::OBJECT_DOMAIN_KEY("objectDomain");
+
+// ---------------------------------------------------------------------------
+
+/** \brief World extent. */
+const ExtentNNPtr
+    Extent::WORLD(Extent::createFromBBOX(-180, -90, 180, 90,
+                                         util::optional<std::string>("World")));
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+std::vector<std::string> WKTConstants::constants_;
+
+const char *WKTConstants::createAndAddToConstantList(const char *text) {
+    WKTConstants::constants_.push_back(text);
+    return text;
+}
+
+#define DEFINE_WKT_CONSTANT(x)                                                 \
+    const std::string WKTConstants::x(createAndAddToConstantList(#x))
+
+DEFINE_WKT_CONSTANT(GEOCCS);
+DEFINE_WKT_CONSTANT(GEOGCS);
+DEFINE_WKT_CONSTANT(DATUM);
+DEFINE_WKT_CONSTANT(UNIT);
+DEFINE_WKT_CONSTANT(SPHEROID);
+DEFINE_WKT_CONSTANT(AXIS);
+DEFINE_WKT_CONSTANT(PRIMEM);
+DEFINE_WKT_CONSTANT(AUTHORITY);
+DEFINE_WKT_CONSTANT(PROJCS);
+DEFINE_WKT_CONSTANT(PROJECTION);
+DEFINE_WKT_CONSTANT(PARAMETER);
+DEFINE_WKT_CONSTANT(VERT_CS);
+DEFINE_WKT_CONSTANT(VERT_DATUM);
+DEFINE_WKT_CONSTANT(COMPD_CS);
+DEFINE_WKT_CONSTANT(TOWGS84);
+DEFINE_WKT_CONSTANT(EXTENSION);
+DEFINE_WKT_CONSTANT(LOCAL_CS);
+DEFINE_WKT_CONSTANT(LOCAL_DATUM);
+
+DEFINE_WKT_CONSTANT(GEODCRS);
+DEFINE_WKT_CONSTANT(LENGTHUNIT);
+DEFINE_WKT_CONSTANT(ANGLEUNIT);
+DEFINE_WKT_CONSTANT(SCALEUNIT);
+DEFINE_WKT_CONSTANT(TIMEUNIT);
+DEFINE_WKT_CONSTANT(ELLIPSOID);
+DEFINE_WKT_CONSTANT(CS);
+DEFINE_WKT_CONSTANT(ID);
+DEFINE_WKT_CONSTANT(PROJCRS);
+DEFINE_WKT_CONSTANT(BASEGEODCRS);
+DEFINE_WKT_CONSTANT(MERIDIAN);
+DEFINE_WKT_CONSTANT(ORDER);
+DEFINE_WKT_CONSTANT(ANCHOR);
+DEFINE_WKT_CONSTANT(CONVERSION);
+DEFINE_WKT_CONSTANT(METHOD);
+DEFINE_WKT_CONSTANT(REMARK);
+DEFINE_WKT_CONSTANT(GEOGCRS);
+DEFINE_WKT_CONSTANT(BASEGEOGCRS);
+DEFINE_WKT_CONSTANT(SCOPE);
+DEFINE_WKT_CONSTANT(AREA);
+DEFINE_WKT_CONSTANT(BBOX);
+DEFINE_WKT_CONSTANT(CITATION);
+DEFINE_WKT_CONSTANT(URI);
+DEFINE_WKT_CONSTANT(VERTCRS);
+DEFINE_WKT_CONSTANT(VDATUM);
+DEFINE_WKT_CONSTANT(COMPOUNDCRS);
+DEFINE_WKT_CONSTANT(PARAMETERFILE);
+DEFINE_WKT_CONSTANT(COORDINATEOPERATION);
+DEFINE_WKT_CONSTANT(SOURCECRS);
+DEFINE_WKT_CONSTANT(TARGETCRS);
+DEFINE_WKT_CONSTANT(INTERPOLATIONCRS);
+DEFINE_WKT_CONSTANT(OPERATIONACCURACY);
+DEFINE_WKT_CONSTANT(CONCATENATEDOPERATION);
+DEFINE_WKT_CONSTANT(STEP);
+DEFINE_WKT_CONSTANT(BOUNDCRS);
+DEFINE_WKT_CONSTANT(ABRIDGEDTRANSFORMATION);
+DEFINE_WKT_CONSTANT(DERIVINGCONVERSION);
+DEFINE_WKT_CONSTANT(TDATUM);
+DEFINE_WKT_CONSTANT(CALENDAR);
+DEFINE_WKT_CONSTANT(TIMEORIGIN);
+DEFINE_WKT_CONSTANT(TIMECRS);
+DEFINE_WKT_CONSTANT(VERTICALEXTENT);
+DEFINE_WKT_CONSTANT(TIMEEXTENT);
+DEFINE_WKT_CONSTANT(USAGE);
+DEFINE_WKT_CONSTANT(DYNAMIC);
+DEFINE_WKT_CONSTANT(FRAMEEPOCH);
+DEFINE_WKT_CONSTANT(MODEL);
+DEFINE_WKT_CONSTANT(VELOCITYGRID);
+DEFINE_WKT_CONSTANT(ENSEMBLE);
+DEFINE_WKT_CONSTANT(MEMBER);
+DEFINE_WKT_CONSTANT(ENSEMBLEACCURACY);
+DEFINE_WKT_CONSTANT(DERIVEDPROJCRS);
+DEFINE_WKT_CONSTANT(BASEPROJCRS);
+DEFINE_WKT_CONSTANT(EDATUM);
+DEFINE_WKT_CONSTANT(ENGCRS);
+DEFINE_WKT_CONSTANT(PDATUM);
+DEFINE_WKT_CONSTANT(PARAMETRICCRS);
+DEFINE_WKT_CONSTANT(PARAMETRICUNIT);
+DEFINE_WKT_CONSTANT(BASEVERTCRS);
+DEFINE_WKT_CONSTANT(BASEENGCRS);
+DEFINE_WKT_CONSTANT(BASEPARAMCRS);
+DEFINE_WKT_CONSTANT(BASETIMECRS);
+
+DEFINE_WKT_CONSTANT(GEODETICCRS);
+DEFINE_WKT_CONSTANT(GEODETICDATUM);
+DEFINE_WKT_CONSTANT(PROJECTEDCRS);
+DEFINE_WKT_CONSTANT(PRIMEMERIDIAN);
+DEFINE_WKT_CONSTANT(GEOGRAPHICCRS);
+DEFINE_WKT_CONSTANT(TRF);
+DEFINE_WKT_CONSTANT(VERTICALCRS);
+DEFINE_WKT_CONSTANT(VERTICALDATUM);
+DEFINE_WKT_CONSTANT(VRF);
+DEFINE_WKT_CONSTANT(TIMEDATUM);
+DEFINE_WKT_CONSTANT(TEMPORALQUANTITY);
+DEFINE_WKT_CONSTANT(ENGINEERINGDATUM);
+DEFINE_WKT_CONSTANT(ENGINEERINGCRS);
+DEFINE_WKT_CONSTANT(PARAMETRICDATUM);
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+namespace common {
+
+/** \brief "Empty"/"None", unit of measure of type NONE. */
+const UnitOfMeasure UnitOfMeasure::NONE("", 1.0, UnitOfMeasure::Type::NONE);
+
+/** \brief Scale unity, unit of measure of type SCALE. */
+const UnitOfMeasure UnitOfMeasure::SCALE_UNITY("unity", 1.0,
+                                               UnitOfMeasure::Type::SCALE,
+                                               Identifier::EPSG, "9201");
+
+/** \brief Parts-per-million, unit of measure of type SCALE. */
+const UnitOfMeasure UnitOfMeasure::PARTS_PER_MILLION("parts per million", 1e-6,
+                                                     UnitOfMeasure::Type::SCALE,
+                                                     Identifier::EPSG, "9202");
+
+/** \brief Metre, unit of measure of type LINEAR (SI unit). */
+const UnitOfMeasure UnitOfMeasure::METRE("metre", 1.0,
+                                         UnitOfMeasure::Type::LINEAR,
+                                         Identifier::EPSG, "9001");
+
+/** \brief Degree, unit of measure of type ANGULAR. */
+const UnitOfMeasure UnitOfMeasure::DEGREE("degree", M_PI / 180.,
+                                          UnitOfMeasure::Type::ANGULAR,
+                                          Identifier::EPSG, "9122");
+
+/** \brief Arc-second, unit of measure of type ANGULAR. */
+const UnitOfMeasure UnitOfMeasure::ARC_SECOND("arc-second", M_PI / 180. / 3600.,
+                                              UnitOfMeasure::Type::ANGULAR,
+                                              Identifier::EPSG, "9104");
+
+/** \brief Grad, unit of measure of type ANGULAR. */
+const UnitOfMeasure UnitOfMeasure::GRAD("grad", M_PI / 200.,
+                                        UnitOfMeasure::Type::ANGULAR,
+                                        Identifier::EPSG, "9105");
+
+/** \brief Radian, unit of measure of type ANGULAR (SI unit). */
+const UnitOfMeasure UnitOfMeasure::RADIAN("radian", 1.0,
+                                          UnitOfMeasure::Type::ANGULAR,
+                                          Identifier::EPSG, "9101");
+
+/** \brief Microradian, unit of measure of type ANGULAR. */
+const UnitOfMeasure UnitOfMeasure::MICRORADIAN("microradian", 1e-6,
+                                               UnitOfMeasure::Type::ANGULAR,
+                                               Identifier::EPSG, "9109");
+
+/** \brief Second, unit of measure of type TIME (SI unit). */
+const UnitOfMeasure UnitOfMeasure::SECOND("second", 1.0,
+                                          UnitOfMeasure::Type::TIME,
+                                          Identifier::EPSG, "1029");
+
+/** \brief Year, unit of measure of type TIME */
+const UnitOfMeasure UnitOfMeasure::YEAR("year", 31556925.445,
+                                        UnitOfMeasure::Type::TIME,
+                                        Identifier::EPSG, "1040");
+
+/** \brief Metre per year, unit of measure of type LINEAR. */
+const UnitOfMeasure UnitOfMeasure::METRE_PER_YEAR("metres per year",
+                                                  1.0 / 31556925.445,
+                                                  UnitOfMeasure::Type::LINEAR,
+                                                  Identifier::EPSG, "1042");
+
+/** \brief Arc-second per year, unit of measure of type ANGULAR. */
+const UnitOfMeasure UnitOfMeasure::ARC_SECOND_PER_YEAR(
+    "arc-seconds per year", M_PI / 180. / 3600. / 31556925.445,
+    UnitOfMeasure::Type::ANGULAR, Identifier::EPSG, "1043");
+
+/** \brief Part-sper-million per year, unit of measure of type SCALE. */
+const UnitOfMeasure UnitOfMeasure::PPM_PER_YEAR("parts per million per year",
+                                                1e-6 / 31556925.445,
+                                                UnitOfMeasure::Type::SCALE,
+                                                Identifier::EPSG, "1036");
+
+} // namespace common
+
+// ---------------------------------------------------------------------------
+
+namespace cs {
+std::map<std::string, const AxisDirection *> AxisDirection::registry;
+
+/** Axis positive direction is north. In a geodetic or projected CRS, north is
+ * defined through the geodetic reference frame. In an engineering CRS, north
+ * may be defined with respect to an engineering object rather than a
+ * geographical direction. */
+const AxisDirection AxisDirection::NORTH("north");
+
+/** Axis positive direction is approximately north-north-east. */
+const AxisDirection AxisDirection::NORTH_NORTH_EAST("northNorthEast");
+
+/** Axis positive direction is approximately north-east. */
+const AxisDirection AxisDirection::NORTH_EAST("northEast");
+
+/** Axis positive direction is approximately east-north-east. */
+const AxisDirection AxisDirection::EAST_NORTH_EAST("eastNorthEast");
+
+/** Axis positive direction is 90deg clockwise from north. */
+const AxisDirection AxisDirection::EAST("east");
+
+/** Axis positive direction is approximately east-south-east. */
+const AxisDirection AxisDirection::EAST_SOUTH_EAST("eastSouthEast");
+
+/** Axis positive direction is approximately south-east. */
+const AxisDirection AxisDirection::SOUTH_EAST("southEast");
+
+/** Axis positive direction is approximately south-south-east. */
+const AxisDirection AxisDirection::SOUTH_SOUTH_EAST("southSouthEast");
+
+/** Axis positive direction is 180deg clockwise from north. */
+const AxisDirection AxisDirection::SOUTH("south");
+
+/** Axis positive direction is approximately south-south-west. */
+const AxisDirection AxisDirection::SOUTH_SOUTH_WEST("southSouthWest");
+
+/** Axis positive direction is approximately south-west. */
+const AxisDirection AxisDirection::SOUTH_WEST("southWest");
+
+/** Axis positive direction is approximately west-south-west. */
+const AxisDirection AxisDirection::WEST_SOUTH_WEST("westSouthWest");
+
+/** Axis positive direction is 270deg clockwise from north. */
+const AxisDirection AxisDirection::WEST("west");
+
+/** Axis positive direction is approximately west-north-west. */
+const AxisDirection AxisDirection::WEST_NORTH_WEST("westNorthWest");
+
+/** Axis positive direction is approximately north-west. */
+const AxisDirection AxisDirection::NORTH_WEST("northWest");
+
+/** Axis positive direction is approximately north-north-west. */
+const AxisDirection AxisDirection::NORTH_NORTH_WEST("northNorthWest");
+
+/** Axis positive direction is up relative to gravity. */
+const AxisDirection AxisDirection::UP("up");
+
+/** Axis positive direction is down relative to gravity. */
+const AxisDirection AxisDirection::DOWN("down");
+
+/** Axis positive direction is in the equatorial plane from the centre of the
+ * modelled Earth towards the intersection of the equator with the prime
+ * meridian. */
+const AxisDirection AxisDirection::GEOCENTRIC_X("geocentricX");
+
+/** Axis positive direction is in the equatorial plane from the centre of the
+ * modelled Earth towards the intersection of the equator and the meridian 90deg
+ * eastwards from the prime meridian. */
+const AxisDirection AxisDirection::GEOCENTRIC_Y("geocentricY");
+
+/** Axis positive direction is from the centre of the modelled Earth parallel to
+ * its rotation axis and towards its north pole. */
+const AxisDirection AxisDirection::GEOCENTRIC_Z("geocentricZ");
+
+/** Axis positive direction is towards higher pixel column. */
+const AxisDirection AxisDirection::COLUMN_POSITIVE("columnPositive");
+
+/** Axis positive direction is towards lower pixel column. */
+const AxisDirection AxisDirection::COLUMN_NEGATIVE("columnNegative");
+
+/** Axis positive direction is towards higher pixel row. */
+const AxisDirection AxisDirection::ROW_POSITIVE("rowPositive");
+
+/** Axis positive direction is towards lower pixel row. */
+const AxisDirection AxisDirection::ROW_NEGATIVE("rowNegative");
+
+/** Axis positive direction is right in display. */
+const AxisDirection AxisDirection::DISPLAY_RIGHT("displayRight");
+
+/** Axis positive direction is left in display. */
+const AxisDirection AxisDirection::DISPLAY_LEFT("displayLeft");
+
+/** Axis positive direction is towards top of approximately vertical display
+ * surface. */
+const AxisDirection AxisDirection::DISPLAY_UP("displayUp");
+
+/** Axis positive direction is towards bottom of approximately vertical display
+ * surface. */
+const AxisDirection AxisDirection::DISPLAY_DOWN("displayDown");
+
+/** Axis positive direction is forward; for an observer at the centre of the
+ * object this is will be towards its front, bow or nose. */
+const AxisDirection AxisDirection::FORWARD("forward");
+
+/** Axis positive direction is aft; for an observer at the centre of the object
+ * this will be towards its back, stern or tail. */
+const AxisDirection AxisDirection::AFT("aft");
+
+/** Axis positive direction is port; for an observer at the centre of the object
+ * this will be towards its left. */
+const AxisDirection AxisDirection::PORT("port");
+
+/** Axis positive direction is starboard; for an observer at the centre of the
+ * object this will be towards its right. */
+const AxisDirection AxisDirection::STARBOARD("starboard");
+
+/** Axis positive direction is clockwise from a specified direction. */
+const AxisDirection AxisDirection::CLOCKWISE("clockwise");
+
+/** Axis positive direction is counter clockwise from a specified direction. */
+const AxisDirection AxisDirection::COUNTER_CLOCKWISE("counterClockwise");
+
+/** Axis positive direction is towards the object. */
+const AxisDirection AxisDirection::TOWARDS("towards");
+
+/** Axis positive direction is away from the object. */
+const AxisDirection AxisDirection::AWAY_FROM("awayFrom");
+
+/** Temporal axis positive direction is towards the future. */
+const AxisDirection AxisDirection::FUTURE("future");
+
+/** Temporal axis positive direction is towards the past. */
+const AxisDirection AxisDirection::PAST("past");
+
+/** Axis positive direction is unspecified. */
+const AxisDirection AxisDirection::UNSPECIFIED("unspecified");
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+
+std::map<std::string, const AxisDirectionWKT1 *> AxisDirectionWKT1::registry;
+
+const AxisDirectionWKT1 AxisDirectionWKT1::NORTH("NORTH");
+const AxisDirectionWKT1 AxisDirectionWKT1::EAST("EAST");
+const AxisDirectionWKT1 AxisDirectionWKT1::SOUTH("SOUTH");
+const AxisDirectionWKT1 AxisDirectionWKT1::WEST("WEST");
+const AxisDirectionWKT1 AxisDirectionWKT1::UP("UP");
+const AxisDirectionWKT1 AxisDirectionWKT1::DOWN("DOWN");
+const AxisDirectionWKT1 AxisDirectionWKT1::OTHER("OTHER");
+
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+const std::string AxisName::Longitude("Longitude");
+const std::string AxisName::Latitude("Latitude");
+const std::string AxisName::Easting("Easting");
+const std::string AxisName::Northing("Northing");
+const std::string AxisName::Westing("Westing");
+const std::string AxisName::Southing("Southing");
+const std::string AxisName::Ellipsoidal_height("Ellipsoidal height");
+const std::string AxisName::Geocentric_X("Geocentric X");
+const std::string AxisName::Geocentric_Y("Geocentric Y");
+const std::string AxisName::Geocentric_Z("Geocentric Z");
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+const std::string AxisAbbreviation::lon("lon");
+const std::string AxisAbbreviation::lat("lat");
+const std::string AxisAbbreviation::E("E");
+const std::string AxisAbbreviation::N("N");
+const std::string AxisAbbreviation::h("h");
+const std::string AxisAbbreviation::X("X");
+const std::string AxisAbbreviation::Y("Y");
+const std::string AxisAbbreviation::Z("Z");
+//! @endcond
+
+} // namespace cs
+
+// ---------------------------------------------------------------------------
+
+/** \brief The realization is by adjustment of a levelling network fixed to one
+ * or more tide gauges. */
+const RealizationMethod RealizationMethod::LEVELLING("levelling");
+/** \brief The realization is through a geoid height model or a height
+ * correction model. This is applied to a specified geodetic CRS. */
+const RealizationMethod RealizationMethod::GEOID("geoid");
+/** \brief The realization is through a tidal model or by tidal predictions. */
+const RealizationMethod RealizationMethod::TIDAL("tidal");
+
+// ---------------------------------------------------------------------------
+
+/** \brief The Greenwich PrimeMeridian */
+const PrimeMeridianNNPtr
+    PrimeMeridian::GREENWICH(PrimeMeridian::createGREENWICH());
+/** \brief The "Reference Meridian" PrimeMeridian.
+ *
+ * This is a meridian of longitude 0 to be used with non-Earth bodies. */
+const PrimeMeridianNNPtr PrimeMeridian::REFERENCE_MERIDIAN(
+    PrimeMeridian::createREFERENCE_MERIDIAN());
+/** \brief The Paris PrimeMeridian */
+const PrimeMeridianNNPtr PrimeMeridian::PARIS(PrimeMeridian::createPARIS());
+
+// ---------------------------------------------------------------------------
+
+/** \brief Earth celestial body */
+const std::string Ellipsoid::EARTH("Earth");
+
+/** \brief The EPSG:7008 / "Clarke 1866" Ellipsoid */
+const EllipsoidNNPtr Ellipsoid::CLARKE_1866(Ellipsoid::createCLARKE_1866());
+
+/** \brief The EPSG:7030 / "WGS 84" Ellipsoid */
+const EllipsoidNNPtr Ellipsoid::WGS84(Ellipsoid::createWGS84());
+
+/** \brief The EPSG:7019 / "GRS 1980" Ellipsoid */
+const EllipsoidNNPtr Ellipsoid::GRS1980(Ellipsoid::createGRS1980());
+
+// ---------------------------------------------------------------------------
+
+/** \brief The EPSG:6267 / "North_American_Datum_1927" GeodeticReferenceFrame */
+const GeodeticReferenceFrameNNPtr GeodeticReferenceFrame::EPSG_6267(
+    GeodeticReferenceFrame::createEPSG_6267());
+
+/** \brief The EPSG:6269 / "North_American_Datum_1983" GeodeticReferenceFrame */
+const GeodeticReferenceFrameNNPtr GeodeticReferenceFrame::EPSG_6269(
+    GeodeticReferenceFrame::createEPSG_6269());
+
+/** \brief The EPSG:6326 / "WGS_1984" GeodeticReferenceFrame */
+const GeodeticReferenceFrameNNPtr GeodeticReferenceFrame::EPSG_6326(
+    GeodeticReferenceFrame::createEPSG_6326());
+
+// ---------------------------------------------------------------------------
+
+/** \brief The proleptic Gregorian calendar. */
+const std::string
+    TemporalDatum::CALENDAR_PROLEPTIC_GREGORIAN("proleptic Gregorian");
+
+// ---------------------------------------------------------------------------
+
+/** \brief EPSG:4978 / "WGS 84" Geocentric */
+const GeodeticCRSNNPtr GeodeticCRS::EPSG_4978(GeodeticCRS::createEPSG_4978());
+
+// ---------------------------------------------------------------------------
+
+/** \brief EPSG:4267 / "NAD27" 2D GeographicCRS */
+const GeographicCRSNNPtr
+    GeographicCRS::EPSG_4267(GeographicCRS::createEPSG_4267());
+
+/** \brief EPSG:4269 / "NAD83" 2D GeographicCRS */
+const GeographicCRSNNPtr
+    GeographicCRS::EPSG_4269(GeographicCRS::createEPSG_4269());
+
+/** \brief EPSG:4326 / "WGS 84" 2D GeographicCRS */
+const GeographicCRSNNPtr
+    GeographicCRS::EPSG_4326(GeographicCRS::createEPSG_4326());
+
+/** \brief OGC:CRS84 / "CRS 84" 2D GeographicCRS (long, lat)*/
+const GeographicCRSNNPtr
+    GeographicCRS::OGC_CRS84(GeographicCRS::createOGC_CRS84());
+
+/** \brief EPSG:4807 / "NTF (Paris)" 2D GeographicCRS */
+const GeographicCRSNNPtr
+    GeographicCRS::EPSG_4807(GeographicCRS::createEPSG_4807());
+
+/** \brief EPSG:4979 / "WGS 84" 3D GeographicCRS */
+const GeographicCRSNNPtr
+    GeographicCRS::EPSG_4979(GeographicCRS::createEPSG_4979());
+
+// ---------------------------------------------------------------------------
+
+NS_PROJ_END
diff --git a/src/iso19111/util.cpp b/src/iso19111/util.cpp
new file mode 100644
index 00000000..ac6357a2
--- /dev/null
+++ b/src/iso19111/util.cpp
@@ -0,0 +1,689 @@
+/******************************************************************************
+ *
+ * Project:  PROJ
+ * Purpose:  ISO19111:2018 implementation
+ * Author:   Even Rouault <even dot rouault at spatialys dot com>
+ *
+ ******************************************************************************
+ * Copyright (c) 2018, Even Rouault <even dot rouault at spatialys dot com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ ****************************************************************************/
+
+#ifndef FROM_PROJ_CPP
+#define FROM_PROJ_CPP
+#endif
+
+#include "proj/util.hpp"
+#include "proj/io.hpp"
+
+#include "proj/internal/internal.hpp"
+
+#include <map>
+#include <memory>
+#include <string>
+
+using namespace NS_PROJ::internal;
+
+#if 0
+namespace dropbox{ namespace oxygen {
+template<> nn<NS_PROJ::util::BaseObjectPtr>::~nn() = default;
+template<> nn<NS_PROJ::util::BoxedValuePtr>::~nn() = default;
+template<> nn<NS_PROJ::util::ArrayOfBaseObjectPtr>::~nn() = default;
+template<> nn<NS_PROJ::util::LocalNamePtr>::~nn() = default;
+template<> nn<NS_PROJ::util::GenericNamePtr>::~nn() = default;
+template<> nn<NS_PROJ::util::NameSpacePtr>::~nn() = default;
+}}
+#endif
+
+NS_PROJ_START
+namespace util {
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct BaseObject::Private {
+    // This is a manual implementation of std::enable_shared_from_this<> that
+    // avoids publicly deriving from it.
+    std::weak_ptr<BaseObject> self_{};
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+BaseObject::BaseObject() : d(internal::make_unique<Private>()) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+BaseObject::~BaseObject() = default;
+
+// ---------------------------------------------------------------------------
+
+BaseObjectNNPtr::~BaseObjectNNPtr() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** Keep a reference to ourselves as an internal weak pointer. So that
+ * extractGeographicBaseObject() can later return a shared pointer on itself.
+ */
+void BaseObject::assignSelf(const BaseObjectNNPtr &self) {
+    assert(self.get() == this);
+    d->self_ = self.as_nullable();
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+BaseObjectNNPtr BaseObject::shared_from_this() const {
+    // This assertion checks that in all code paths where we create a
+    // shared pointer, we took care of assigning it to self_, by calling
+    // assignSelf();
+    return NN_CHECK_ASSERT(d->self_.lock());
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct BoxedValue::Private {
+    BoxedValue::Type type_{BoxedValue::Type::INTEGER};
+    std::string stringValue_{};
+    int integerValue_{};
+    bool booleanValue_{};
+
+    explicit Private(const std::string &stringValueIn)
+        : type_(BoxedValue::Type::STRING), stringValue_(stringValueIn) {}
+
+    explicit Private(int integerValueIn)
+        : type_(BoxedValue::Type::INTEGER), integerValue_(integerValueIn) {}
+
+    explicit Private(bool booleanValueIn)
+        : type_(BoxedValue::Type::BOOLEAN), booleanValue_(booleanValueIn) {}
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+BoxedValue::BoxedValue() : d(internal::make_unique<Private>(std::string())) {}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Constructs a BoxedValue from a string.
+ */
+BoxedValue::BoxedValue(const char *stringValueIn)
+    : d(internal::make_unique<Private>(
+          std::string(stringValueIn ? stringValueIn : ""))) {}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Constructs a BoxedValue from a string.
+ */
+BoxedValue::BoxedValue(const std::string &stringValueIn)
+    : d(internal::make_unique<Private>(stringValueIn)) {}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Constructs a BoxedValue from an integer.
+ */
+BoxedValue::BoxedValue(int integerValueIn)
+    : d(internal::make_unique<Private>(integerValueIn)) {}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Constructs a BoxedValue from a boolean.
+ */
+BoxedValue::BoxedValue(bool booleanValueIn)
+    : d(internal::make_unique<Private>(booleanValueIn)) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+BoxedValue::BoxedValue(const BoxedValue &other)
+    : d(internal::make_unique<Private>(*other.d)) {}
+
+// ---------------------------------------------------------------------------
+
+BoxedValue::~BoxedValue() = default;
+
+// ---------------------------------------------------------------------------
+
+const BoxedValue::Type &BoxedValue::type() const { return d->type_; }
+
+// ---------------------------------------------------------------------------
+
+const std::string &BoxedValue::stringValue() const { return d->stringValue_; }
+
+// ---------------------------------------------------------------------------
+
+int BoxedValue::integerValue() const { return d->integerValue_; }
+
+// ---------------------------------------------------------------------------
+
+bool BoxedValue::booleanValue() const { return d->booleanValue_; }
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct ArrayOfBaseObject::Private {
+    std::vector<BaseObjectNNPtr> values_{};
+};
+//! @endcond
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+ArrayOfBaseObject::ArrayOfBaseObject() : d(internal::make_unique<Private>()) {}
+
+// ---------------------------------------------------------------------------
+
+ArrayOfBaseObject::~ArrayOfBaseObject() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Adds an object to the array.
+ *
+ * @param obj the object to add.
+ */
+void ArrayOfBaseObject::add(const BaseObjectNNPtr &obj) {
+    d->values_.emplace_back(obj);
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+std::vector<BaseObjectNNPtr>::const_iterator ArrayOfBaseObject::begin() const {
+    return d->values_.begin();
+}
+
+// ---------------------------------------------------------------------------
+
+std::vector<BaseObjectNNPtr>::const_iterator ArrayOfBaseObject::end() const {
+    return d->values_.end();
+}
+
+// ---------------------------------------------------------------------------
+
+bool ArrayOfBaseObject::empty() const { return d->values_.empty(); }
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a ArrayOfBaseObject.
+ *
+ * @return a new ArrayOfBaseObject.
+ */
+ArrayOfBaseObjectNNPtr ArrayOfBaseObject::create() {
+    return ArrayOfBaseObject::nn_make_shared<ArrayOfBaseObject>();
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct PropertyMap::Private {
+    std::list<std::pair<std::string, BaseObjectNNPtr>> list_{};
+
+    // cppcheck-suppress functionStatic
+    void set(const std::string &key, const BoxedValueNNPtr &val) {
+        for (auto &pair : list_) {
+            if (pair.first == key) {
+                pair.second = val;
+                return;
+            }
+        }
+        list_.emplace_back(key, val);
+    }
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+PropertyMap::PropertyMap() : d(internal::make_unique<Private>()) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+PropertyMap::PropertyMap(const PropertyMap &other)
+    : d(internal::make_unique<Private>(*(other.d))) {}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+PropertyMap::~PropertyMap() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+const BaseObjectNNPtr *PropertyMap::get(const std::string &key) const {
+    for (const auto &pair : d->list_) {
+        if (pair.first == key) {
+            return &(pair.second);
+        }
+    }
+    return nullptr;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Set a BaseObjectNNPtr as the value of a key. */
+PropertyMap &PropertyMap::set(const std::string &key,
+                              const BaseObjectNNPtr &val) {
+    for (auto &pair : d->list_) {
+        if (pair.first == key) {
+            pair.second = val;
+            return *this;
+        }
+    }
+    d->list_.emplace_back(key, val);
+    return *this;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Set a string as the value of a key. */
+PropertyMap &PropertyMap::set(const std::string &key, const std::string &val) {
+    d->set(key, util::nn_make_shared<BoxedValue>(val));
+    return *this;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Set a string as the value of a key. */
+PropertyMap &PropertyMap::set(const std::string &key, const char *val) {
+    d->set(key, util::nn_make_shared<BoxedValue>(val));
+    return *this;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Set a integer as the value of a key. */
+PropertyMap &PropertyMap::set(const std::string &key, int val) {
+    d->set(key, util::nn_make_shared<BoxedValue>(val));
+    return *this;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Set a boolean as the value of a key. */
+PropertyMap &PropertyMap::set(const std::string &key, bool val) {
+    d->set(key, util::nn_make_shared<BoxedValue>(val));
+    return *this;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Set a vector of strings as the value of a key. */
+PropertyMap &PropertyMap::set(const std::string &key,
+                              const std::vector<std::string> &arrayIn) {
+    ArrayOfBaseObjectNNPtr array = ArrayOfBaseObject::create();
+    for (const auto &str : arrayIn) {
+        array->add(util::nn_make_shared<BoxedValue>(str));
+    }
+    return set(key, array);
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+bool PropertyMap::getStringValue(
+    const std::string &key,
+    std::string &outVal) const // throw(InvalidValueTypeException)
+{
+    for (const auto &pair : d->list_) {
+        if (pair.first == key) {
+            auto genVal = dynamic_cast<const BoxedValue *>(pair.second.get());
+            if (genVal && genVal->type() == BoxedValue::Type::STRING) {
+                outVal = genVal->stringValue();
+                return true;
+            }
+            throw InvalidValueTypeException("Invalid value type for " + key);
+        }
+    }
+    return false;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+bool PropertyMap::getStringValue(
+    const std::string &key,
+    optional<std::string> &outVal) const // throw(InvalidValueTypeException)
+{
+    for (const auto &pair : d->list_) {
+        if (pair.first == key) {
+            auto genVal = dynamic_cast<const BoxedValue *>(pair.second.get());
+            if (genVal && genVal->type() == BoxedValue::Type::STRING) {
+                outVal = genVal->stringValue();
+                return true;
+            }
+            throw InvalidValueTypeException("Invalid value type for " + key);
+        }
+    }
+    return false;
+}
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct GenericName::Private {};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+GenericName::GenericName() : d(internal::make_unique<Private>()) {}
+
+// ---------------------------------------------------------------------------
+
+GenericName::GenericName(const GenericName &other)
+    : d(internal::make_unique<Private>(*other.d)) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+GenericName::~GenericName() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct NameSpace::Private {
+    GenericNamePtr name{};
+    bool isGlobal{};
+    std::string separator = std::string(":");
+    std::string separatorHead = std::string(":");
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+NameSpace::NameSpace(const GenericNamePtr &nameIn)
+    : d(internal::make_unique<Private>()) {
+    d->name = nameIn;
+}
+
+// ---------------------------------------------------------------------------
+
+NameSpace::NameSpace(const NameSpace &other)
+    : d(internal::make_unique<Private>(*other.d)) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+NameSpace::~NameSpace() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns whether this is a global namespace. */
+bool NameSpace::isGlobal() const { return d->isGlobal; }
+
+// ---------------------------------------------------------------------------
+
+NameSpaceNNPtr NameSpace::getGlobalFromThis() const {
+    NameSpaceNNPtr ns(NameSpace::nn_make_shared<NameSpace>(*this));
+    ns->d->isGlobal = true;
+    ns->d->name = LocalName::make_shared<LocalName>("global");
+    return ns;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns the name of this namespace. */
+const GenericNamePtr &NameSpace::name() const { return d->name; }
+
+// ---------------------------------------------------------------------------
+
+const std::string &NameSpace::separator() const { return d->separator; }
+
+// ---------------------------------------------------------------------------
+
+NameSpaceNNPtr NameSpace::createGLOBAL() {
+    NameSpaceNNPtr ns(NameSpace::nn_make_shared<NameSpace>(
+        LocalName::make_shared<LocalName>("global")));
+    ns->d->isGlobal = true;
+    return ns;
+}
+
+// ---------------------------------------------------------------------------
+
+const NameSpaceNNPtr NameSpace::GLOBAL(NameSpace::createGLOBAL());
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+struct LocalName::Private {
+    NameSpacePtr scope{};
+    std::string name{};
+};
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+LocalName::LocalName(const std::string &name)
+    : d(internal::make_unique<Private>()) {
+    d->name = name;
+}
+
+// ---------------------------------------------------------------------------
+
+LocalName::LocalName(const NameSpacePtr &ns, const std::string &name)
+    : d(internal::make_unique<Private>()) {
+    d->scope = ns ? ns : static_cast<NameSpacePtr>(NameSpace::GLOBAL);
+    d->name = name;
+}
+
+// ---------------------------------------------------------------------------
+
+LocalName::LocalName(const LocalName &other)
+    : GenericName(other), d(internal::make_unique<Private>(*other.d)) {}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+LocalName::~LocalName() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+const NameSpacePtr LocalName::scope() const {
+    if (d->scope)
+        return d->scope;
+    return NameSpace::GLOBAL;
+}
+
+// ---------------------------------------------------------------------------
+
+GenericNameNNPtr LocalName::toFullyQualifiedName() const {
+    if (scope()->isGlobal())
+        return LocalName::nn_make_shared<LocalName>(*this);
+
+    return LocalName::nn_make_shared<LocalName>(
+        d->scope->getGlobalFromThis(),
+        d->scope->name()->toFullyQualifiedName()->toString() +
+            d->scope->separator() + d->name);
+}
+
+// ---------------------------------------------------------------------------
+
+std::string LocalName::toString() const { return d->name; }
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a NameSpace.
+ *
+ * @param name name of the namespace.
+ * @param properties Properties. Allowed keys are "separator" and
+ * "separator.head".
+ * @return a new NameFactory.
+ */
+NameSpaceNNPtr NameFactory::createNameSpace(const GenericNameNNPtr &name,
+                                            const PropertyMap &properties) {
+    NameSpaceNNPtr ns(NameSpace::nn_make_shared<NameSpace>(name));
+    properties.getStringValue("separator", ns->d->separator);
+    properties.getStringValue("separator.head", ns->d->separatorHead);
+
+    return ns;
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a LocalName.
+ *
+ * @param scope scope.
+ * @param name string of the local name.
+ * @return a new LocalName.
+ */
+LocalNameNNPtr NameFactory::createLocalName(const NameSpacePtr &scope,
+                                            const std::string &name) {
+    return LocalName::nn_make_shared<LocalName>(scope, name);
+}
+
+// ---------------------------------------------------------------------------
+
+/** \brief Instanciate a GenericName.
+ *
+ * @param scope scope.
+ * @param parsedNames the components of the name.
+ * @return a new GenericName.
+ */
+GenericNameNNPtr
+NameFactory::createGenericName(const NameSpacePtr &scope,
+                               const std::vector<std::string> &parsedNames) {
+    std::string name;
+    const std::string separator(scope ? scope->separator()
+                                      : NameSpace::GLOBAL->separator());
+    bool first = true;
+    for (const auto &str : parsedNames) {
+        if (!first)
+            name += separator;
+        first = false;
+        name += str;
+    }
+    return LocalName::nn_make_shared<LocalName>(scope, name);
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+CodeList::~CodeList() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+CodeList &CodeList::operator=(const CodeList &other) {
+    name_ = other.name_;
+    return *this;
+}
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+Exception::Exception(const char *message) : msg_(message) {}
+
+// ---------------------------------------------------------------------------
+
+Exception::Exception(const std::string &message) : msg_(message) {}
+
+// ---------------------------------------------------------------------------
+
+Exception::Exception(const Exception &) = default;
+
+// ---------------------------------------------------------------------------
+
+Exception::~Exception() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** Return the exception text. */
+const char *Exception::what() const noexcept { return msg_.c_str(); }
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+InvalidValueTypeException::InvalidValueTypeException(const char *message)
+    : Exception(message) {}
+
+// ---------------------------------------------------------------------------
+
+InvalidValueTypeException::InvalidValueTypeException(const std::string &message)
+    : Exception(message) {}
+
+// ---------------------------------------------------------------------------
+
+InvalidValueTypeException::~InvalidValueTypeException() = default;
+
+// ---------------------------------------------------------------------------
+
+InvalidValueTypeException::InvalidValueTypeException(
+    const InvalidValueTypeException &) = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+UnsupportedOperationException::UnsupportedOperationException(
+    const char *message)
+    : Exception(message) {}
+
+// ---------------------------------------------------------------------------
+
+UnsupportedOperationException::UnsupportedOperationException(
+    const std::string &message)
+    : Exception(message) {}
+
+// ---------------------------------------------------------------------------
+
+UnsupportedOperationException::~UnsupportedOperationException() = default;
+
+// ---------------------------------------------------------------------------
+
+UnsupportedOperationException::UnsupportedOperationException(
+    const UnsupportedOperationException &) = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+//! @cond Doxygen_Suppress
+IComparable::~IComparable() = default;
+//! @endcond
+
+// ---------------------------------------------------------------------------
+
+/** \brief Returns whether an object is equivalent to another one.
+ * @param other other object to compare to
+ * @param criterion comparaison criterion.
+ * @return true if objects are equivalent.
+ */
+bool IComparable::isEquivalentTo(const IComparable *other,
+                                 Criterion criterion) const {
+    return _isEquivalentTo(other, criterion);
+}
+
+// ---------------------------------------------------------------------------
+
+} // namespace util
+NS_PROJ_END