diff options
Diffstat (limited to 'src/c_api.cpp')
| -rw-r--r-- | src/c_api.cpp | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/src/c_api.cpp b/src/c_api.cpp index a5ed1509..fed91750 100644 --- a/src/c_api.cpp +++ b/src/c_api.cpp @@ -55,6 +55,7 @@ #include "proj_experimental.h" #include "projects.h" // clang-format on +#include "proj_constants.h" using namespace NS_PROJ::common; using namespace NS_PROJ::crs; @@ -2526,6 +2527,72 @@ PJ_OBJ *proj_obj_create_conversion(PJ_CONTEXT *ctx, const char *name, // --------------------------------------------------------------------------- +/** + * \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_unref(), 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) { |