createOperations(): tune sorting of transformations so that the ones with greater 'version numbers' are prefered over other ones, when all other comparison criteria are equal. Helps with Amersfoort RD New to EPSG:4326

3 files changed, 44 insertions, 3 deletions

diff --git a/src/iso19111/coordinateoperation.cpp b/src/iso19111/coordinateoperation.cpp
index 0e61d2ee..65ef2b77 100644
--- a/src/iso19111/coordinateoperation.cpp
+++ b/src/iso19111/coordinateoperation.cpp
@@ -11380,8 +11380,31 @@ struct SortFunction {
             return false;
         }
 
-        // Arbitrary final criterion
-        return a_name < b_name;
+        // Arbitrary final criterion. We actually return the greater element
+        // first, so that "Amersfoort to WGS 84 (4)" is presented before
+        // "Amersfoort to WGS 84 (3)", which is probably a better guess.
+
+        // Except for French NTF (Paris) to NTF, where the (1) conversion
+        // should be preferred because in the remarks of (2), it is mentionned
+        // OGP prefers value from IGN Paris (code 1467)...
+        if (a_name.find("NTF (Paris) to NTF (1)") != std::string::npos &&
+            b_name.find("NTF (Paris) to NTF (2)") != std::string::npos) {
+            return true;
+        }
+        if (a_name.find("NTF (Paris) to NTF (2)") != std::string::npos &&
+            b_name.find("NTF (Paris) to NTF (1)") != std::string::npos) {
+            return false;
+        }
+        if (a_name.find("NTF (Paris) to RGF93 (1)") != std::string::npos &&
+            b_name.find("NTF (Paris) to RGF93 (2)") != std::string::npos) {
+            return true;
+        }
+        if (a_name.find("NTF (Paris) to RGF93 (2)") != std::string::npos &&
+            b_name.find("NTF (Paris) to RGF93 (1)") != std::string::npos) {
+            return false;
+        }
+
+        return a_name > b_name;
     }
 
     bool operator()(const CoordinateOperationNNPtr &a,
diff --git a/test/cli/testprojinfo_out.dist b/test/cli/testprojinfo_out.dist
index 5e1f1dd5..5d36f42e 100644
--- a/test/cli/testprojinfo_out.dist
+++ b/test/cli/testprojinfo_out.dist
@@ -1048,8 +1048,8 @@ Candidate operations found: 7
 unknown id, GDA94 to GDA2020 (1) + Conversion from GDA2020 (geog2D) to GDA2020 (geocentric) + GDA2020 to WGS 84 (G1762) (1) + Conversion from WGS 84 (G1762) (geocentric) to WGS 84 (G1762) (geog2D), 0.21 m, Australia - GDA
 unknown id, GDA94 to WGS 84 (1) + WGS 84 to WGS 84 (G1762), 5 m, Australia - GDA
 unknown id, Conversion from GDA94 (geog2D) to GDA94 (geocentric) + Inverse of ITRF2008 to GDA94 (1) + Inverse of WGS 84 (G1762) to ITRF2008 (1) + Conversion from WGS 84 (G1762) (geocentric) to WGS 84 (G1762) (geog2D), 0.04 m, Australia - onshore and EEZ
-unknown id, GDA94 to GDA2020 (2) + Conversion from GDA2020 (geog2D) to GDA2020 (geocentric) + GDA2020 to WGS 84 (G1762) (1) + Conversion from WGS 84 (G1762) (geocentric) to WGS 84 (G1762) (geog2D), 0.25 m, Australia - onshore
 unknown id, GDA94 to GDA2020 (3) + Conversion from GDA2020 (geog2D) to GDA2020 (geocentric) + GDA2020 to WGS 84 (G1762) (1) + Conversion from WGS 84 (G1762) (geocentric) to WGS 84 (G1762) (geog2D), 0.25 m, Australia - onshore
+unknown id, GDA94 to GDA2020 (2) + Conversion from GDA2020 (geog2D) to GDA2020 (geocentric) + GDA2020 to WGS 84 (G1762) (1) + Conversion from WGS 84 (G1762) (geocentric) to WGS 84 (G1762) (geog2D), 0.25 m, Australia - onshore
 unknown id, GDA94 to GDA2020 (5) + Conversion from GDA2020 (geog2D) to GDA2020 (geocentric) + GDA2020 to WGS 84 (G1762) (1) + Conversion from WGS 84 (G1762) (geocentric) to WGS 84 (G1762) (geog2D), 0.25 m, Cocos (Keeling) Islands - onshore
 unknown id, GDA94 to GDA2020 (4) + Conversion from GDA2020 (geog2D) to GDA2020 (geocentric) + GDA2020 to WGS 84 (G1762) (1) + Conversion from WGS 84 (G1762) (geocentric) to WGS 84 (G1762) (geog2D), 0.25 m, Christmas Island - onshore
 
diff --git a/test/unit/test_operation.cpp b/test/unit/test_operation.cpp
index eca5d59b..23f3489b 100644
--- a/test/unit/test_operation.cpp
+++ b/test/unit/test_operation.cpp
@@ -6214,6 +6214,24 @@ TEST(operation, projCRS_to_projCRS_through_geog3D) {
 
 // ---------------------------------------------------------------------------
 
+TEST(operation, transform_from_amersfoort_rd_new_to_epsg_4326) {
+    auto authFactory =
+        AuthorityFactory::create(DatabaseContext::create(), "EPSG");
+    auto ctxt = CoordinateOperationContext::create(authFactory, nullptr, 0.0);
+    auto list = CoordinateOperationFactory::create()->createOperations(
+        authFactory->createCoordinateReferenceSystem("28992"),
+        authFactory->createCoordinateReferenceSystem("4326"), ctxt);
+    ASSERT_EQ(list.size(), 2U);
+    // The order matters: "Amersfoort to WGS 84 (4)" replaces "Amersfoort to WGS
+    // 84 (3)"
+    EXPECT_EQ(list[0]->nameStr(),
+              "Inverse of RD New + Amersfoort to WGS 84 (4)");
+    EXPECT_EQ(list[1]->nameStr(),
+              "Inverse of RD New + Amersfoort to WGS 84 (3)");
+}
+
+// ---------------------------------------------------------------------------
+
 TEST(operation, boundCRS_of_geogCRS_to_geogCRS) {
     auto boundCRS = BoundCRS::createFromTOWGS84(
         GeographicCRS::EPSG_4807, std::vector<double>{1, 2, 3, 4, 5, 6, 7});