WKT and PROJJSON: add import/export of geoid model of VertCRS

8 files changed, 125 insertions, 14 deletions

diff --git a/data/projjson.schema.json b/data/projjson.schema.json
index 60fca6df..e71e5031 100644
--- a/data/projjson.schema.json
+++ b/data/projjson.schema.json
@@ -1,5 +1,5 @@
 {
-  "$id": "https://proj.org/schemas/v0.1/projjson.schema.json",
+  "$id": "https://proj.org/schemas/v0.2/projjson.schema.json",
   "$schema": "http://json-schema.org/draft-07/schema#",
   "description": "Schema for PROJJSON",
   "$comment": "This file exists both in data/ and in schemas/vXXX/. Keep both in sync. And if changing the value of $id, change PROJJSON_CURRENT_VERSION accordingly in io.cpp",
@@ -932,6 +932,15 @@
         },
         "datum_ensemble": { "$ref": "#/definitions/datum_ensemble" },
         "coordinate_system": { "$ref": "#/definitions/coordinate_system" },
+        "geoid_model": {
+          "type": "object",
+          "properties": {
+            "name": { "type": "string" },
+            "id": { "$ref": "#/definitions/id" }
+          },
+          "required" : [ "name" ],
+          "additionalProperties": false
+        },
         "$schema" : {},
         "scope": {},
         "area": {},
diff --git a/include/proj/internal/io_internal.hpp b/include/proj/internal/io_internal.hpp
index 781dfa6c..1e2508cc 100644
--- a/include/proj/internal/io_internal.hpp
+++ b/include/proj/internal/io_internal.hpp
@@ -134,6 +134,7 @@ class WKTConstants {
     static const std::string BASEPARAMCRS;
     static const std::string BASETIMECRS;
     static const std::string VERSION;
+    static const std::string GEOIDMODEL; // WKT2-2019
 
     // WKT2 alternate (longer or shorter)
     static const std::string GEODETICCRS;
diff --git a/src/iso19111/crs.cpp b/src/iso19111/crs.cpp
index 26725e24..b9b38c80 100644
--- a/src/iso19111/crs.cpp
+++ b/src/iso19111/crs.cpp
@@ -2478,6 +2478,14 @@ void VerticalCRS::_exportToWKT(io::WKTFormatter *formatter) const {
     cs->_exportToWKT(formatter);
     formatter->setOutputAxis(oldAxisOutputRule);
 
+    if (isWKT2 && formatter->use2019Keywords() && !d->geoidModel.empty()) {
+        const auto &model = d->geoidModel[0];
+        formatter->startNode(io::WKTConstants::GEOIDMODEL, false);
+        formatter->addQuotedString(model->nameStr());
+        model->formatID(formatter);
+        formatter->endNode();
+    }
+
     ObjectUsage::baseExportToWKT(formatter);
     formatter->endNode();
 }
@@ -2539,6 +2547,15 @@ void VerticalCRS::_exportToJSON(
     formatter->setOmitTypeInImmediateChild();
     coordinateSystem()->_exportToJSON(formatter);
 
+    if (!d->geoidModel.empty()) {
+        const auto &model = d->geoidModel[0];
+        writer.AddObjKey("geoid_model");
+        auto objectContext2(formatter->MakeObjectContext(nullptr, false));
+        writer.AddObjKey("name");
+        writer.Add(model->nameStr());
+        model->formatID(formatter);
+    }
+
     ObjectUsage::baseExportToJSON(formatter);
 }
 //! @endcond
@@ -2572,7 +2589,8 @@ void VerticalCRS::addLinearUnitConvert(
  * cs::VerticalCS.
  *
  * @param properties See \ref general_properties.
- * At minimum the name should be defined.
+ * At minimum the name should be defined. The GEOID_MODEL property can be set
+ * to a TransformationNNPtr object.
  * @param datumIn The datum of the CRS.
  * @param csIn a VerticalCS.
  * @return new VerticalCRS.
@@ -2592,7 +2610,8 @@ VerticalCRS::create(const util::PropertyMap &properties,
  * 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.
+ * At minimum the name should be defined. The GEOID_MODEL property can be set
+ * to a TransformationNNPtr object.
  * @param datumIn The datum of the CRS, or nullptr
  * @param datumEnsembleIn The datum ensemble of the CRS, or nullptr.
  * @param csIn a VerticalCS.
@@ -2607,6 +2626,14 @@ VerticalCRS::create(const util::PropertyMap &properties,
                                                       csIn));
     crs->assignSelf(crs);
     crs->setProperties(properties);
+    const auto geoidModelPtr = properties.get("GEOID_MODEL");
+    if (geoidModelPtr) {
+        auto transf = util::nn_dynamic_pointer_cast<operation::Transformation>(
+            *geoidModelPtr);
+        if (transf) {
+            crs->d->geoidModel.emplace_back(NN_NO_CHECK(transf));
+        }
+    }
     return crs;
 }
 
diff --git a/src/iso19111/io.cpp b/src/iso19111/io.cpp
index fc66b6c9..116a8b78 100644
--- a/src/iso19111/io.cpp
+++ b/src/iso19111/io.cpp
@@ -89,7 +89,7 @@ static const std::string emptyString{};
 
 // If changing that value, change it in data/projjson.schema.json as well
 #define PROJJSON_CURRENT_VERSION                                               \
-    "https://proj.org/schemas/v0.1/projjson.schema.json"
+    "https://proj.org/schemas/v0.2/projjson.schema.json"
 //! @endcond
 
 #if 0
@@ -3820,8 +3820,22 @@ CRSNNPtr WKTParser::Private::buildVerticalCRS(const WKTNodeNNPtr &node) {
         ThrowNotExpectedCSType("vertical");
     }
 
+    auto &props = buildProperties(node);
+    auto &geoidModelNode = nodeP->lookForChild(WKTConstants::GEOIDMODEL);
+    if (!isNull(geoidModelNode)) {
+        auto &propsModel = buildProperties(geoidModelNode);
+        const auto dummyCRS = VerticalCRS::create(
+            PropertyMap(), datum, datumEnsemble, NN_NO_CHECK(verticalCS));
+        const auto model(Transformation::create(
+            propsModel, dummyCRS, dummyCRS, nullptr,
+            OperationMethod::create(PropertyMap(),
+                                    std::vector<OperationParameterNNPtr>()),
+            {}, {}));
+        props.set("GEOID_MODEL", model);
+    }
+
     auto crs = nn_static_pointer_cast<CRS>(VerticalCRS::create(
-        buildProperties(node), datum, datumEnsemble, NN_NO_CHECK(verticalCS)));
+        props, datum, datumEnsemble, NN_NO_CHECK(verticalCS)));
 
     if (!isNull(datumNode)) {
         auto &extensionNode = datumNode->lookForChild(WKTConstants::EXTENSION);
@@ -4987,7 +5001,22 @@ VerticalCRSNNPtr JSONParser::buildVerticalCRS(const json &j) {
     if (!verticalCS) {
         throw ParsingException("expected a vertical CS");
     }
-    return VerticalCRS::create(buildProperties(j), datum, datumEnsemble,
+
+    auto props = buildProperties(j);
+    if (j.contains("geoid_model")) {
+        auto geoidModelJ = getObject(j, "geoid_model");
+        auto propsModel = buildProperties(geoidModelJ);
+        const auto dummyCRS = VerticalCRS::create(
+            PropertyMap(), datum, datumEnsemble, NN_NO_CHECK(verticalCS));
+        const auto model(Transformation::create(
+            propsModel, dummyCRS, dummyCRS, nullptr,
+            OperationMethod::create(PropertyMap(),
+                                    std::vector<OperationParameterNNPtr>()),
+            {}, {}));
+        props.set("GEOID_MODEL", model);
+    }
+
+    return VerticalCRS::create(props, datum, datumEnsemble,
                                NN_NO_CHECK(verticalCS));
 }
 
diff --git a/src/iso19111/static.cpp b/src/iso19111/static.cpp
index 824047f0..0ed08c95 100644
--- a/src/iso19111/static.cpp
+++ b/src/iso19111/static.cpp
@@ -274,6 +274,7 @@ DEFINE_WKT_CONSTANT(BASEENGCRS);
 DEFINE_WKT_CONSTANT(BASEPARAMCRS);
 DEFINE_WKT_CONSTANT(BASETIMECRS);
 DEFINE_WKT_CONSTANT(VERSION);
+DEFINE_WKT_CONSTANT(GEOIDMODEL);
 
 DEFINE_WKT_CONSTANT(GEODETICCRS);
 DEFINE_WKT_CONSTANT(GEODETICDATUM);
diff --git a/test/cli/testprojinfo_out.dist b/test/cli/testprojinfo_out.dist
index c1d9f3e0..40b8330a 100644
--- a/test/cli/testprojinfo_out.dist
+++ b/test/cli/testprojinfo_out.dist
@@ -137,7 +137,7 @@ GEOGCS["GCS_WGS_1984",DATUM["D_WGS_1984",SPHEROID["WGS_1984",6378137.0,298.25722
 
 PROJJSON:
 {
-  "$schema": "https://proj.org/schemas/v0.1/projjson.schema.json",
+  "$schema": "https://proj.org/schemas/v0.2/projjson.schema.json",
   "type": "GeographicCRS",
   "name": "WGS 84",
   "datum": {
diff --git a/test/unit/test_c_api.cpp b/test/unit/test_c_api.cpp
index 8ac5a511..5e6d1924 100644
--- a/test/unit/test_c_api.cpp
+++ b/test/unit/test_c_api.cpp
@@ -3600,7 +3600,7 @@ TEST_F(CApi, proj_as_projjson) {
         EXPECT_EQ(std::string(projjson),
                   "{\n"
                   "  \"$schema\": "
-                  "\"https://proj.org/schemas/v0.1/projjson.schema.json\",\n"
+                  "\"https://proj.org/schemas/v0.2/projjson.schema.json\",\n"
                   "  \"type\": \"Ellipsoid\",\n"
                   "  \"name\": \"WGS 84\",\n"
                   "  \"semi_major_axis\": 6378137,\n"
diff --git a/test/unit/test_io.cpp b/test/unit/test_io.cpp
index 074a59b9..6bb93e97 100644
--- a/test/unit/test_io.cpp
+++ b/test/unit/test_io.cpp
@@ -1960,16 +1960,21 @@ TEST(wkt_parse, vertcrs_VRF_WKT2) {
 // ---------------------------------------------------------------------------
 
 TEST(wkt_parse, vertcrs_with_GEOIDMODEL) {
-    auto wkt = "VERTCRS[\"CGVD2013\","
-               "    VRF[\"Canadian Geodetic Vertical Datum of 2013\"],"
-               "    CS[vertical,1],"
-               "        AXIS[\"gravity-related height (H)\",up],"
-               "        LENGTHUNIT[\"metre\",1.0],"
-               "    GEOIDMODEL[\"CGG2013\",ID[\"EPSG\",6648]]]";
+    auto wkt = "VERTCRS[\"CGVD2013\",\n"
+               "    VDATUM[\"Canadian Geodetic Vertical Datum of 2013\"],\n"
+               "    CS[vertical,1],\n"
+               "        AXIS[\"gravity-related height (H)\",up,\n"
+               "            LENGTHUNIT[\"metre\",1]],\n"
+               "    GEOIDMODEL[\"CGG2013\",\n"
+               "        ID[\"EPSG\",6648]]]";
 
     auto obj = WKTParser().createFromWKT(wkt);
     auto crs = nn_dynamic_pointer_cast<VerticalCRS>(obj);
     ASSERT_TRUE(crs != nullptr);
+    EXPECT_EQ(
+        crs->exportToWKT(
+            WKTFormatter::create(WKTFormatter::Convention::WKT2_2019).get()),
+        wkt);
 }
 
 // ---------------------------------------------------------------------------
@@ -10808,6 +10813,45 @@ TEST(json_import, vertical_crs_with_datum_ensemble) {
 
 // ---------------------------------------------------------------------------
 
+TEST(json_import, vertical_crs_with_geoid_model) {
+    auto json = "{\n"
+                "  \"$schema\": \"foo\",\n"
+                "  \"type\": \"VerticalCRS\",\n"
+                "  \"name\": \"CGVD2013\",\n"
+                "  \"datum\": {\n"
+                "    \"type\": \"VerticalReferenceFrame\",\n"
+                "    \"name\": \"Canadian Geodetic Vertical Datum of 2013\"\n"
+                "  },\n"
+                "  \"coordinate_system\": {\n"
+                "    \"subtype\": \"vertical\",\n"
+                "    \"axis\": [\n"
+                "      {\n"
+                "        \"name\": \"Gravity-related height\",\n"
+                "        \"abbreviation\": \"H\",\n"
+                "        \"direction\": \"up\",\n"
+                "        \"unit\": \"metre\"\n"
+                "      }\n"
+                "    ]\n"
+                "  },\n"
+                "  \"geoid_model\": {\n"
+                "    \"name\": \"CGG2013\",\n"
+                "    \"id\": {\n"
+                "      \"authority\": \"EPSG\",\n"
+                "      \"code\": 6648\n"
+                "    }\n"
+                "  }\n"
+                "}";
+
+    // No database
+    auto obj = createFromUserInput(json, nullptr);
+    auto vcrs = nn_dynamic_pointer_cast<VerticalCRS>(obj);
+    ASSERT_TRUE(vcrs != nullptr);
+    EXPECT_EQ(vcrs->exportToJSON(&(JSONFormatter::create()->setSchema("foo"))),
+              json);
+}
+
+// ---------------------------------------------------------------------------
+
 TEST(json_import, parametric_crs) {
     auto json = "{\n"
                 "  \"$schema\": \"foo\",\n"