EPSG Codes & CRS IDs

MapControl/Shared/AutoEquirectangularProjection.cs

@@ -18,10 +18,10 @@ namespace MapControl
     {
         public const string DefaultCrsId = "AUTO2:42004";
 
-        public AutoEquirectangularProjection()
+        public AutoEquirectangularProjection(string crsId = DefaultCrsId)
         {
             Type = MapProjectionType.NormalCylindrical;
-            CrsId = DefaultCrsId;
+            CrsId = crsId;
         }
 
         public override Point? LocationToMap(Location location)

MapControl/Shared/AzimuthalEquidistantProjection.cs

@@ -15,7 +15,9 @@ namespace MapControl
     /// </summary>
     public class AzimuthalEquidistantProjection : AzimuthalProjection
     {
-        public AzimuthalEquidistantProjection(string crsId)
+        public const string DefaultCrsId = "AUTO2:97003"; // proprietary CRS ID
+
+        public AzimuthalEquidistantProjection(string crsId = DefaultCrsId)
         {
             CrsId = crsId;
         }

MapControl/Shared/EquirectangularProjection.cs

@@ -17,13 +17,12 @@ namespace MapControl
     /// </summary>
     public class EquirectangularProjection : MapProjection
     {
-        public const int DefaultEpsgCode = 4326;
+        public const int EpsgCode = 4326;
-        public static readonly string DefaultCrsId = $"EPSG:{DefaultEpsgCode}";
 
-        public EquirectangularProjection()
+        public EquirectangularProjection(string crsId = "EPSG:4326")
         {
             Type = MapProjectionType.NormalCylindrical;
-            CrsId = DefaultCrsId;
+            CrsId = crsId;
         }
 
         public override Point GetRelativeScale(Location location)

MapControl/Shared/Etrs89UtmProjection.cs

@@ -26,7 +26,7 @@ namespace MapControl
             }
 
             Zone = zone;
-            CrsId = $"EPSG:{Zone - FirstZone + FirstZoneEpsgCode}";
+            CrsId = $"EPSG:{25800 + Zone}";
 
             // GRS 1980
             EquatorialRadius = 6378137d;

MapControl/Shared/GnomonicProjection.cs

@@ -17,9 +17,9 @@ namespace MapControl
     {
         public const string DefaultCrsId = "AUTO2:97001"; // GeoServer non-standard CRS ID
 
-        public GnomonicProjection()
+        public GnomonicProjection(string crsId = DefaultCrsId)
         {
-            CrsId = DefaultCrsId;
+            CrsId = crsId;
         }
 
         public override Point? LocationToMap(Location location)

MapControl/Shared/MapProjection.cs

@@ -42,7 +42,7 @@ namespace MapControl
         /// <summary>
         /// Gets or sets an optional projection center.
         /// </summary>
-        public virtual Location Center { get; set; } = new Location();
+        public virtual Location Center { get; protected internal set; } = new Location();
 
         /// <summary>
         /// Gets the relative map scale at the specified Location.
@@ -118,7 +118,7 @@ namespace MapControl
         /// </summary>
         public virtual string GetCrsValue()
         {
-            return CrsId.StartsWith("AUTO:") || CrsId.StartsWith("AUTO2:")
+            return CrsId.StartsWith("AUTO2:") || CrsId.StartsWith("AUTO:")
                 ? string.Format(CultureInfo.InvariantCulture, "{0},1,{1},{2}", CrsId, Center.Longitude, Center.Latitude)
                 : CrsId;
         }

MapControl/Shared/MapProjectionFactory.cs

@@ -16,93 +16,67 @@ namespace MapControl
 
         public virtual MapProjection GetProjection(int epsgCode)
         {
-            MapProjection projection = null;
-
             switch (epsgCode)
             {
-                case WorldMercatorProjection.DefaultEpsgCode:
+                case WorldMercatorProjection.EpsgCode:
-                    projection = new WorldMercatorProjection();
+                    return new WorldMercatorProjection();
-                    break;
 
-                case WebMercatorProjection.DefaultEpsgCode:
+                case WebMercatorProjection.EpsgCode:
-                    projection = new WebMercatorProjection();
+                    return new WebMercatorProjection();
-                    break;
 
-                case EquirectangularProjection.DefaultEpsgCode:
+                case EquirectangularProjection.EpsgCode:
-                    projection = new EquirectangularProjection();
+                    return new EquirectangularProjection();
-                    break;
 
-                case UpsNorthProjection.DefaultEpsgCode:
+                case UpsNorthProjection.EpsgCode:
-                    projection = new UpsNorthProjection();
+                    return new UpsNorthProjection();
-                    break;
 
-                case UpsSouthProjection.DefaultEpsgCode:
+                case UpsSouthProjection.EpsgCode:
-                    projection = new UpsSouthProjection();
+                    return new UpsSouthProjection();
-                    break;
 
                 case var c when c >= Etrs89UtmProjection.FirstZoneEpsgCode && c <= Etrs89UtmProjection.LastZoneEpsgCode:
-                    projection = new Etrs89UtmProjection(epsgCode % 100);
+                    return new Etrs89UtmProjection(epsgCode % 100);
-                    break;
 
                 case var c when c >= Nad83UtmProjection.FirstZoneEpsgCode && c <= Nad83UtmProjection.LastZoneEpsgCode:
-                    projection = new Nad83UtmProjection(epsgCode % 100);
+                    return new Nad83UtmProjection(epsgCode % 100);
-                    break;
 
                 case var c when c >= Wgs84UtmProjection.FirstZoneNorthEpsgCode && c <= Wgs84UtmProjection.LastZoneNorthEpsgCode:
-                    projection = new Wgs84UtmProjection(epsgCode % 100, true);
+                    return new Wgs84UtmProjection(epsgCode % 100, true);
-                    break;
 
                 case var c when c >= Wgs84UtmProjection.FirstZoneSouthEpsgCode && c <= Wgs84UtmProjection.LastZoneSouthEpsgCode:
-                    projection = new Wgs84UtmProjection(epsgCode % 100, false);
+                    return new Wgs84UtmProjection(epsgCode % 100, false);
-                    break;
 
                 default:
-                    break;
+                    return null;
             }
-
-            return projection;
         }
 
         public virtual MapProjection GetProjection(string crsId)
         {
-            if (crsId.StartsWith("EPSG:") && int.TryParse(crsId.Substring(5), out int epsgCode))
-            {
-                return GetProjection(epsgCode);
-            }
-
-            MapProjection projection = null;
-
             switch (crsId)
             {
                 case Wgs84AutoUtmProjection.DefaultCrsId:
-                    projection = new Wgs84AutoUtmProjection();
+                    return new Wgs84AutoUtmProjection();
-                    break;
 
                 case OrthographicProjection.DefaultCrsId:
-                    projection = new OrthographicProjection();
+                    return new OrthographicProjection();
-                    break;
 
                 case AutoEquirectangularProjection.DefaultCrsId:
-                    projection = new AutoEquirectangularProjection();
+                    return new AutoEquirectangularProjection();
-                    break;
 
                 case GnomonicProjection.DefaultCrsId:
-                    projection = new GnomonicProjection();
+                    return new GnomonicProjection();
-                    break;
 
                 case StereographicProjection.DefaultCrsId:
-                    projection = new StereographicProjection();
+                    return new StereographicProjection();
-                    break;
 
-                case "AUTO2:97003": // proprietary CRS ID
+                case AzimuthalEquidistantProjection.DefaultCrsId:
-                    projection = new AzimuthalEquidistantProjection(crsId);
+                    return new AzimuthalEquidistantProjection();
-                    break;
 
                 default:
-                    break;
+                    return crsId.StartsWith("EPSG:") && int.TryParse(crsId.Substring(5), out int epsgCode)
+                        ? GetProjection(epsgCode)
+                        : null;
             }
-
-            return projection;
         }
     }
 }

MapControl/Shared/Nad83UtmProjection.cs

@@ -26,7 +26,7 @@ namespace MapControl
             }
 
             Zone = zone;
-            CrsId = $"EPSG:{Zone - FirstZone + FirstZoneEpsgCode}";
+            CrsId = $"EPSG:{26900 + Zone}";
 
             // GRS 1980
             EquatorialRadius = 6378137d;

MapControl/Shared/OrthographicProjection.cs

@@ -17,9 +17,9 @@ namespace MapControl
     {
         public const string DefaultCrsId = "AUTO2:42003";
 
-        public OrthographicProjection()
+        public OrthographicProjection(string crsId = DefaultCrsId)
         {
-            CrsId = DefaultCrsId;
+            CrsId = crsId;
         }
 
         public override Point? LocationToMap(Location location)

MapControl/Shared/PolarStereographicProjection.cs

@@ -117,12 +117,11 @@ namespace MapControl
     /// </summary>
     public class UpsNorthProjection : PolarStereographicProjection
     {
-        public const int DefaultEpsgCode = 32661;
+        public const int EpsgCode = 32661;
-        public static readonly string DefaultCrsId = $"EPSG:{DefaultEpsgCode}";
 
-        public UpsNorthProjection()
+        public UpsNorthProjection(string crsId = "EPSG:32661")
         {
-            CrsId = DefaultCrsId;
+            CrsId = crsId;
             IsNorth = true;
         }
     }
@@ -132,12 +131,11 @@ namespace MapControl
     /// </summary>
     public class UpsSouthProjection : PolarStereographicProjection
     {
-        public const int DefaultEpsgCode = 32761;
+        public const int EpsgCode = 32761;
-        public static readonly string DefaultCrsId = $"EPSG:{DefaultEpsgCode}";
 
-        public UpsSouthProjection()
+        public UpsSouthProjection(string crsId = "EPSG:32761")
         {
-            CrsId = DefaultCrsId;
+            CrsId = crsId;
             IsNorth = false;
         }
     }

MapControl/Shared/StereographicProjection.cs

@@ -17,9 +17,9 @@ namespace MapControl
     {
         public const string DefaultCrsId = "AUTO2:97002"; // GeoServer non-standard CRS ID
 
-        public StereographicProjection()
+        public StereographicProjection(string crsId = DefaultCrsId)
         {
-            CrsId = DefaultCrsId;
+            CrsId = crsId;
         }
 
         public override Point? LocationToMap(Location location)

MapControl/Shared/WebMercatorProjection.cs

@@ -15,13 +15,12 @@ namespace MapControl
     /// </summary>
     public class WebMercatorProjection : MapProjection
     {
-        public const int DefaultEpsgCode = 3857;
+        public const int EpsgCode = 3857;
-        public static readonly string DefaultCrsId = $"EPSG:{DefaultEpsgCode}";
 
-        public WebMercatorProjection()
+        public WebMercatorProjection(string crsId = "EPSG:3857")
         {
             Type = MapProjectionType.WebMercator;
-            CrsId = DefaultCrsId;
+            CrsId = crsId;
         }
 
         public override Point GetRelativeScale(Location location)

MapControl/Shared/Wgs84UtmProjection.cs

@@ -21,27 +21,21 @@ namespace MapControl
         public int Zone { get; private set; }
         public bool IsNorth { get; private set; }
 
-        protected Wgs84UtmProjection()
-        {
-        }
-
         public Wgs84UtmProjection(int zone, bool north)
         {
             SetZone(zone, north);
         }
 
-        protected void SetZone(int zone, bool north, string crsId = null)
+        protected void SetZone(int zone, bool north)
         {
             if (zone < FirstZone || zone > LastZone)
             {
                 throw new ArgumentException($"Invalid WGS84 UTM zone {zone}.", nameof(zone));
             }
 
-            var epsgCode = zone - FirstZone + (north ? FirstZoneNorthEpsgCode : FirstZoneSouthEpsgCode);
-
             Zone = zone;
             IsNorth = north;
-            CrsId = crsId ?? $"EPSG:{epsgCode}";
+            CrsId = $"EPSG:{(north ? 32600 : 32700) + zone}";
             EquatorialRadius = Wgs84EquatorialRadius;
             Flattening = Wgs84Flattening;
             ScaleFactor = DefaultScaleFactor;
@@ -58,38 +52,43 @@ namespace MapControl
     {
         public const string DefaultCrsId = "AUTO2:42001";
 
-        public Wgs84AutoUtmProjection(bool useZoneCrsId = false)
+        private readonly string autoCrsId;
-        {
-            UseZoneCrsId = useZoneCrsId;
-            UpdateZone();
-        }
 
-        public bool UseZoneCrsId { get; }
+        public Wgs84AutoUtmProjection(string crsId = DefaultCrsId)
+            : base(31, true)
+        {
+            autoCrsId = crsId;
+
+            if (!string.IsNullOrEmpty(autoCrsId))
+            {
+                CrsId = autoCrsId;
+            }
+        }
 
         public override Location Center
         {
             get => base.Center;
-            set
+            protected internal set
             {
                 if (!Equals(base.Center, value))
                 {
                     base.Center = value;
-                    UpdateZone();
+
+                    var lon = Location.NormalizeLongitude(value.Longitude);
+                    var zone = (int)Math.Floor(lon / 6d) + 31;
+                    var north = value.Latitude >= 0d;
+
+                    if (Zone != zone || IsNorth != north)
+                    {
+                        SetZone(zone, north);
+
+                        if (!string.IsNullOrEmpty(autoCrsId))
+                        {
+                            CrsId = autoCrsId;
+                        }
+                    }
                 }
             }
         }
-
-        private void UpdateZone()
-        {
-            var lon = Location.NormalizeLongitude(Center.Longitude);
-            var zone = (int)Math.Floor(lon / 6d) + 31;
-            var north = Center.Latitude >= 0d;
-
-            if (Zone != zone || IsNorth != north || string.IsNullOrEmpty(CrsId))
-            {
-                SetZone(zone, north, UseZoneCrsId ? null : DefaultCrsId);
-            }
-        }
-
     }
 }

MapControl/Shared/WorldMercatorProjection.cs

@@ -15,13 +15,12 @@ namespace MapControl
     /// </summary>
     public class WorldMercatorProjection : MapProjection
     {
-        public const int DefaultEpsgCode = 3395;
+        public const int EpsgCode = 3395;
-        public static readonly string DefaultCrsId = $"EPSG:{DefaultEpsgCode}";
 
-        public WorldMercatorProjection()
+        public WorldMercatorProjection(string crsId = "EPSG:3395")
         {
             Type = MapProjectionType.NormalCylindrical;
-            CrsId = DefaultCrsId;
+            CrsId = crsId;
         }
 
         public override Point GetRelativeScale(Location location)

MapProjections/Shared/GeoApiProjectionFactory.cs

@@ -8,75 +8,64 @@ namespace MapControl.Projections
 {
     public class GeoApiProjectionFactory : MapProjectionFactory
     {
+        public static GeoApiProjectionFactory GetInstance()
+        {
+            if (!(Instance is GeoApiProjectionFactory factory))
+            {
+                factory = new GeoApiProjectionFactory();
+                Instance = factory;
+            }
+
+            return factory;
+        }
+
         public Dictionary<int, string> CoordinateSystemWkts { get; } = new Dictionary<int, string>();
 
         public override MapProjection GetProjection(int epsgCode)
         {
-            MapProjection projection = null;
+            switch (epsgCode)
-
-            if (CoordinateSystemWkts.TryGetValue(epsgCode, out string wkt))
             {
-                projection = new GeoApiProjection(wkt);
+                case WorldMercatorProjection.EpsgCode:
+                    return new WorldMercatorProjection();
+
+                case WebMercatorProjection.EpsgCode:
+                    return new WebMercatorProjection();
+
+                case int c when c >= Ed50UtmProjection.FirstZoneEpsgCode && c <= Ed50UtmProjection.LastZoneEpsgCode:
+                    return new Ed50UtmProjection(epsgCode % 100);
+
+                case var c when c >= Etrs89UtmProjection.FirstZoneEpsgCode && c <= Etrs89UtmProjection.LastZoneEpsgCode:
+                    return new Etrs89UtmProjection(epsgCode % 100);
+
+                case var c when c >= Nad27UtmProjection.FirstZoneEpsgCode && c <= Nad27UtmProjection.LastZoneEpsgCode:
+                    return new Nad27UtmProjection(epsgCode % 100);
+
+                case var c when c >= Nad83UtmProjection.FirstZoneEpsgCode && c <= Nad83UtmProjection.LastZoneEpsgCode:
+                    return new Nad83UtmProjection(epsgCode % 100);
+
+                case var c when c >= Wgs84UtmProjection.FirstZoneNorthEpsgCode && c <= Wgs84UtmProjection.LastZoneNorthEpsgCode:
+                    return new Wgs84UtmProjection(epsgCode % 100, true);
+
+                case var c when c >= Wgs84UtmProjection.FirstZoneSouthEpsgCode && c <= Wgs84UtmProjection.LastZoneSouthEpsgCode:
+                    return new Wgs84UtmProjection(epsgCode % 100, false);
+
+                default:
+                    return CoordinateSystemWkts.TryGetValue(epsgCode, out string wkt)
+                        ? new GeoApiProjection(wkt)
+                        : base.GetProjection(epsgCode);
             }
-            else
-            {
-                switch (epsgCode)
-                {
-                    case WorldMercatorProjection.DefaultEpsgCode:
-                        projection = new WorldMercatorProjection();
-                        break;
-
-                    case WebMercatorProjection.DefaultEpsgCode:
-                        projection = new WebMercatorProjection();
-                        break;
-
-                    case int c when c >= Ed50UtmProjection.FirstZoneEpsgCode && c <= Ed50UtmProjection.LastZoneEpsgCode:
-                        projection = new Ed50UtmProjection(epsgCode % 100);
-                        break;
-
-                    case var c when c >= Etrs89UtmProjection.FirstZoneEpsgCode && c <= Etrs89UtmProjection.LastZoneEpsgCode:
-                        projection = new Etrs89UtmProjection(epsgCode % 100);
-                        break;
-
-                    case var c when c >= Nad27UtmProjection.FirstZoneEpsgCode && c <= Nad27UtmProjection.LastZoneEpsgCode:
-                        projection = new Nad27UtmProjection(epsgCode % 100);
-                        break;
-
-                    case var c when c >= Nad83UtmProjection.FirstZoneEpsgCode && c <= Nad83UtmProjection.LastZoneEpsgCode:
-                        projection = new Nad83UtmProjection(epsgCode % 100);
-                        break;
-
-                    case var c when c >= Wgs84UtmProjection.FirstZoneNorthEpsgCode && c <= Wgs84UtmProjection.LastZoneNorthEpsgCode:
-                        projection = new Wgs84UtmProjection(epsgCode % 100, true);
-                        break;
-
-                    case var c when c >= Wgs84UtmProjection.FirstZoneSouthEpsgCode && c <= Wgs84UtmProjection.LastZoneSouthEpsgCode:
-                        projection = new Wgs84UtmProjection(epsgCode % 100, false);
-                        break;
-
-                    default:
-                        break;
-                }
-            }
-
-            return projection ?? base.GetProjection(epsgCode);
         }
 
         public override MapProjection GetProjection(string crsId)
         {
-            MapProjection projection = null;
-
             switch (crsId)
             {
                 case Wgs84AutoUtmProjection.DefaultCrsId:
-                    projection = new Wgs84AutoUtmProjection();
+                    return new Wgs84AutoUtmProjection();
-                    break;
 
                 default:
-                    break;
+                    return base.GetProjection(crsId);
             }
-
-            return projection ?? base.GetProjection(crsId);
         }
     }
 }

MapProjections/Shared/WebMercatorProjection.cs

@@ -18,7 +18,7 @@ namespace MapControl.Projections
     /// </summary>
     public class WebMercatorProjection : GeoApiProjection
     {
-        public const int DefaultEpsgCode = 3857;
+        public const int EpsgCode = 3857;
 
         public WebMercatorProjection()
         {

MapProjections/Shared/Wgs84UtmProjection.cs

@@ -22,10 +22,6 @@ namespace MapControl.Projections
         public int Zone { get; private set; }
         public bool IsNorth { get; private set; }
 
-        protected Wgs84UtmProjection()
-        {
-        }
-
         public Wgs84UtmProjection(int zone, bool north)
         {
             SetZone(zone, north);
@@ -51,40 +47,41 @@ namespace MapControl.Projections
     {
         public const string DefaultCrsId = "AUTO2:42001";
 
-        public Wgs84AutoUtmProjection(bool useZoneCrsId = false)
+        private readonly string autoCrsId;
-        {
-            UseZoneCrsId = useZoneCrsId;
-            UpdateZone();
-        }
 
-        public bool UseZoneCrsId { get; }
+        public Wgs84AutoUtmProjection(string crsId = DefaultCrsId)
+            : base(31, true)
+        {
+            autoCrsId = crsId;
+
+            if (!string.IsNullOrEmpty(autoCrsId))
+            {
+                CrsId = autoCrsId;
+            }
+        }
 
         public override Location Center
         {
             get => base.Center;
-            set
+            protected set
             {
                 if (!Equals(base.Center, value))
                 {
                     base.Center = value;
-                    UpdateZone();
-                }
-            }
-        }
 
-        private void UpdateZone()
+                    var lon = Location.NormalizeLongitude(value.Longitude);
-        {
+                    var zone = (int)Math.Floor(lon / 6d) + 31;
-            var lon = Location.NormalizeLongitude(Center.Longitude);
+                    var north = value.Latitude >= 0d;
-            var zone = (int)Math.Floor(lon / 6d) + 31;
-            var north = Center.Latitude >= 0d;
 
-            if (Zone != zone || IsNorth != north || string.IsNullOrEmpty(CrsId))
+                    if (Zone != zone || IsNorth != north)
-            {
+                    {
-                SetZone(zone, north);
+                        SetZone(zone, north);
 
-                if (!UseZoneCrsId)
+                        if (!string.IsNullOrEmpty(autoCrsId))
-                {
+                        {
-                    CrsId = DefaultCrsId;
+                            CrsId = autoCrsId;
+                        }
+                    }
                 }
             }
         }

MapProjections/Shared/WorldMercatorProjection.cs

@@ -17,7 +17,7 @@ namespace MapControl.Projections
     /// </summary>
     public class WorldMercatorProjection : GeoApiProjection
     {
-        public const int DefaultEpsgCode = 3395;
+        public const int EpsgCode = 3395;
 
         public WorldMercatorProjection()
         {
@@ -43,7 +43,7 @@ namespace MapControl.Projections
                 + "AUTHORITY[\"EPSG\",\"9001\"]],"
                 + "AXIS[\"Easting\",EAST],"
                 + "AXIS[\"Northing\",NORTH],"
-                + "AUTHORITY[\"EPSG\",\"3395\"]]";
+                + $"AUTHORITY[\"EPSG\",\"{EpsgCode}\"]]";
         }
 
         public override Point GetRelativeScale(Location location)