Use ProjNET instead of ProjNet4GeoAPI

MapProjections/Shared/ProjNetMapProjection.cs

@@ -0,0 +1,137 @@
+using ProjNet.CoordinateSystems;
+using ProjNet.CoordinateSystems.Transformations;
+using System;
+#if WPF
+using System.Windows;
+#elif AVALONIA
+using Avalonia;
+#endif
+
+namespace MapControl.Projections
+{
+    /// <summary>
+    /// MapProjection based on ProjNet.
+    /// </summary>
+    public class ProjNetMapProjection : MapProjection
+    {
+        protected ProjNetMapProjection()
+        {
+        }
+
+        public ProjNetMapProjection(string coordinateSystemWkt)
+        {
+            CoordinateSystemWkt = coordinateSystemWkt;
+        }
+
+        /// <summary>
+        /// Gets or sets an OGC Well-known text representation of a coordinate system,
+        /// i.e. a PROJCS[...] or GEOGCS[...] string as used by https://epsg.io or http://spatialreference.org.
+        /// Setting this property updates the CoordinateSystem property with an ICoordinateSystem created from the WKT string.
+        /// </summary>
+        public string CoordinateSystemWkt
+        {
+            get => CoordinateSystem?.WKT;
+            protected set => CoordinateSystem = new CoordinateSystemFactory().CreateFromWkt(value) as ProjectedCoordinateSystem;
+        }
+
+        /// <summary>
+        /// Gets or sets the ICoordinateSystem of the MapProjection.
+        /// </summary>
+        public ProjectedCoordinateSystem CoordinateSystem
+        {
+            get;
+            protected set
+            {
+                field = value ?? throw new ArgumentNullException(nameof(value));
+
+                var transformFactory = new CoordinateTransformationFactory();
+
+                LocationToMapTransform = transformFactory
+                    .CreateFromCoordinateSystems(GeographicCoordinateSystem.WGS84, field)
+                    .MathTransform;
+
+                MapToLocationTransform = transformFactory
+                    .CreateFromCoordinateSystems(field, GeographicCoordinateSystem.WGS84)
+                    .MathTransform;
+
+                CrsId = !string.IsNullOrEmpty(field.Authority) && field.AuthorityCode > 0
+                    ? $"{field.Authority}:{field.AuthorityCode}"
+                    : string.Empty;
+
+                if (CrsId == "EPSG:3857")
+                {
+                    Type = MapProjectionType.WebMercator;
+                }
+                else
+                {
+                    var projection = field.Projection ??
+                        throw new ArgumentException("CoordinateSystem.Projection must not be null.", nameof(value));
+
+                    var centralMeridian = projection.GetParameter("central_meridian") ?? projection.GetParameter("longitude_of_origin");
+                    var centralParallel = projection.GetParameter("central_parallel") ?? projection.GetParameter("latitude_of_origin");
+                    var falseEasting = projection.GetParameter("false_easting");
+                    var falseNorthing = projection.GetParameter("false_northing");
+
+                    if ((centralMeridian == null || centralMeridian.Value == 0d) &&
+                        (centralParallel == null || centralParallel.Value == 0d) &&
+                        (falseEasting == null || falseEasting.Value == 0d) &&
+                        (falseNorthing == null || falseNorthing.Value == 0d))
+                    {
+                        Type = MapProjectionType.NormalCylindrical;
+                    }
+                    else if (projection.Name.StartsWith("UTM") || projection.Name.StartsWith("Transverse"))
+                    {
+                        Type = MapProjectionType.TransverseCylindrical;
+                    }
+                }
+            }
+        }
+
+        public MathTransform LocationToMapTransform { get; private set; }
+
+        public MathTransform MapToLocationTransform { get; private set; }
+
+        public override Point RelativeScale(double latitude, double longitude)
+        {
+            var k = CoordinateSystem?.Projection?.GetParameter("scale_factor")?.Value ?? 1d;
+
+            return new Point(k, k);
+        }
+
+        public override Point? LocationToMap(double latitude, double longitude)
+        {
+            if (LocationToMapTransform == null)
+            {
+                throw new InvalidOperationException("The CoordinateSystem property is not set.");
+            }
+
+            try
+            {
+                var coordinate = LocationToMapTransform.Transform([longitude, latitude]);
+                return new Point(coordinate[0], coordinate[1]);
+            }
+            catch
+            {
+                return null;
+            }
+        }
+
+        public override Location MapToLocation(double x, double y)
+        {
+            if (MapToLocationTransform == null)
+            {
+                throw new InvalidOperationException("The CoordinateSystem property is not set.");
+            }
+
+            try
+            {
+                var coordinate = MapToLocationTransform.Transform([x, y]);
+                return new Location(coordinate[1], coordinate[0]);
+            }
+            catch
+            {
+                return null;
+            }
+        }
+    }
+}