Add support for Lambert Tangential Conformal Conic Projection (#133)

Author: mario-mu

src/ProjNet/CoordinateSystems/Projections/LambertConformalConic2SP.cs

@@ -113,10 +113,12 @@ protected LambertConformalConic2SP(IEnumerable<ProjectionParameter> parameters,
 			Name = "Lambert_Conformal_Conic_2SP";
 			Authority = "EPSG";
 			AuthorityCode = 9802;
-			
-            //Check for missing parameters
-			double lat1 = DegreesToRadians(_Parameters.GetParameterValue("standard_parallel_1"));
-            double lat2 = DegreesToRadians(_Parameters.GetParameterValue("standard_parallel_2"));
+
+			//Check for missing parameters
+			//Since this implementation supports conic 1SP and 2SP we add the support for the 1SP implementation here.
+			//There is no need for standard_parallel_1 and standard_parallel_2 parameters in this version: https://pro.arcgis.com/en/pro-app/latest/help/mapping/properties/lambert-conformal-conic.htm
+			double lat1 = DegreesToRadians(_Parameters.GetParameterValue("standard_parallel_1", new[] { "latitude_of_origin" }));
+			double lat2 = DegreesToRadians(_Parameters.GetParameterValue("standard_parallel_2", new[] { "latitude_of_origin" }));
 
 			double sin_po;                  /* sin value                            */
 			double cos_po;                  /* cos value                            */

src/ProjNet/CoordinateSystems/Projections/ProjectionsRegistry.cs

@@ -25,21 +25,22 @@ static ProjectionsRegistry()
             Register("mercator_auxiliary_sphere", typeof(MercatorAuxiliarySphere));
             Register("pseudo_mercator", typeof(PseudoMercator));
             Register("popular_visualisation_pseudo_mercator", typeof(PseudoMercator));
-            Register("google_mercator", typeof(PseudoMercator));
+            Register("google_mercator", typeof(PseudoMercator));
 
             Register("transverse_mercator", typeof(TransverseMercator));
             Register("gauss_kruger", typeof(TransverseMercator));
 
-            Register("albers", typeof(AlbersProjection));
+            Register("albers", typeof(AlbersProjection));
             Register("albers_conic_equal_area", typeof(AlbersProjection));
-
+
             Register("krovak", typeof(KrovakProjection));
-
+
             Register("polyconic", typeof(PolyconicProjection));
 
-            Register("lambert_conformal_conic", typeof(LambertConformalConic2SP));
+            Register("lambert_conformal_conic", typeof(LambertConformalConic2SP));
             Register("lambert_conformal_conic_2sp", typeof(LambertConformalConic2SP));
             Register("lambert_conic_conformal_(2sp)", typeof(LambertConformalConic2SP));
+            Register("lambert_tangential_conformal_conic_projection", typeof(LambertConformalConic2SP));
 
             Register("lambert_azimuthal_equal_area", typeof(LambertAzimuthalEqualAreaProjection));
 

test/ProjNet.Tests/CoordinateTransformTests.cs

@@ -1166,6 +1166,29 @@ public void TestPopularVisualizationPseudoMercatorProjectionRegistry()
             Assert.NotNull(transformation);
         }
 
+        [Test]
+        public void TestLamberTangentialConformalConicProjectionRegistryAndTransformation()
+        {
+            string sourceWkt = "PROJCS[\"WORLD-LM-TAN\",GEOGCS[\"LL84\",DATUM[\"WGS84\",SPHEROID[\"WGS84\",6378137.000,298.25722356]],PRIMEM[\"Greenwich\",0],UNIT[\"Degree\",0.017453292519943295]],PROJECTION[\"Lambert Tangential Conformal Conic Projection\"],PARAMETER[\"false_easting\",0.000],PARAMETER[\"false_northing\",0.000],PARAMETER[\"scale_factor\",1.000000000000],PARAMETER[\"central_meridian\",0.00000000000000],PARAMETER[\"latitude_of_origin\",1.00000000000000],UNIT[\"Meter\",1.00000000000000]]";
+            string targetWkt = "PROJCS[\"WGS84.PseudoMercator\",GEOGCS[\"LL84\",DATUM[\"WGS84\",SPHEROID[\"WGS84\",6378137.000,298.25722356]],PRIMEM[\"Greenwich\",0],UNIT[\"Degree\",0.017453292519943295]],PROJECTION[\"Popular Visualisation Pseudo Mercator\"],PARAMETER[\"false_easting\",0.000],PARAMETER[\"false_northing\",0.000],PARAMETER[\"central_meridian\",0.00000000000000],UNIT[\"Meter\",1.00000000000000]]";
+
+            var sourceCoordinateSystem = GetCoordinateSystem(sourceWkt);
+            Assert.NotNull(sourceCoordinateSystem);
+
+            var targetCoordinateSystem = GetCoordinateSystem(targetWkt);
+            Assert.NotNull(targetCoordinateSystem);
+
+            var transformation = GetTransformation(sourceCoordinateSystem, targetCoordinateSystem);
+            Assert.NotNull(transformation);
+
+            // Test the transformation with a known points. Tested with AutoCAD map 3D
+            double[] pGeo = new[] { 4101119.6855, -229063.8661 }; // Nairobi, Kenya
+            double[] pUtm = transformation.MathTransform.Transform(pGeo);
+
+            double[] expected = new[] { 4098998.6422, -142387.5532 };
+            Assert.IsTrue(ToleranceLessThan(pUtm, expected, 0.05), TransformationError("LambertConicConformal2SP", expected, pUtm));
+        }
+
         internal static CoordinateSystem GetCoordinateSystem(string wkt)
         {
             var coordinateSystemFactory = new CoordinateSystemFactory();