IMapLayer.SupportedMapProjections

MapControl/Shared/MapBase.MapLayer.cs

@@ -22,6 +22,7 @@ namespace MapControl
     {
         Brush MapBackground { get; }
         Brush MapForeground { get; }
+        IReadOnlyCollection<string> SupportedMapProjections { get; }
     }
 
     public partial class MapBase

MapControl/Shared/MapImageLayer.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using System.Linq;
 using System.Threading.Tasks;
 #if WPF
@@ -126,6 +127,8 @@ namespace MapControl
         /// </summary>
         public double LoadingProgress => (double)GetValue(LoadingProgressProperty);
 
+        public abstract IReadOnlyCollection<string> SupportedMapProjections { get; }
+
         protected override void SetParentMap(MapBase map)
         {
             if (map != null)
@@ -183,7 +186,11 @@ namespace MapControl
                 ImageSource image = null;
                 BoundingBox boundingBox = null;
 
-                if (ParentMap != null && ParentMap.ActualWidth > 0d && ParentMap.ActualHeight > 0d)
+                if (ParentMap != null &&
+                    ParentMap.ActualWidth > 0d &&
+                    ParentMap.ActualHeight > 0d &&
+                    SupportedMapProjections != null &&
+                    SupportedMapProjections.Contains(ParentMap.MapProjection.CrsId))
                 {
                     var width = ParentMap.ActualWidth * RelativeImageSize;
                     var height = ParentMap.ActualHeight * RelativeImageSize;

MapControl/Shared/MapTileLayer.cs

@@ -1,4 +1,7 @@
 using System;
+using System.Collections.Generic;
+using System.Linq;
+
 #if WPF
 using System.Windows;
 using System.Windows.Media;
@@ -33,22 +36,24 @@ namespace MapControl
 
         private const int TileSize = 256;
 
-        private static readonly Point MapTopLeft = new Point(
+        private static readonly Point MapTopLeft = new(-180d * MapProjection.Wgs84MeterPerDegree,
-            -180d * MapProjection.Wgs84MeterPerDegree, 180d * MapProjection.Wgs84MeterPerDegree);
+                                                        180d * MapProjection.Wgs84MeterPerDegree);
 
         /// <summary>
         /// A default MapTileLayer using OpenStreetMap data.
         /// </summary>
-        public static MapTileLayer OpenStreetMapTileLayer => new MapTileLayer
+        public static MapTileLayer OpenStreetMapTileLayer => new()
         {
             TileSource = new TileSource { UriTemplate = "https://tile.openstreetmap.org/{z}/{x}/{y}.png" },
             SourceName = "OpenStreetMap",
             Description = "© [OpenStreetMap Contributors](http://www.openstreetmap.org/copyright)"
         };
 
+        public override IReadOnlyCollection<string> SupportedMapProjections { get; } = ["EPSG:3857"];
+
         public TileMatrix TileMatrix { get; private set; }
 
-        public TileCollection Tiles { get; private set; } = new TileCollection();
+        public TileCollection Tiles { get; private set; } = [];
 
         /// <summary>
         /// Minimum zoom level supported by the MapTileLayer. Default value is 0.
@@ -113,7 +118,7 @@ namespace MapControl
 
         protected override void UpdateTileLayerAsync(bool resetTiles)
         {
-            if (ParentMap == null || ParentMap.MapProjection.Type != MapProjectionType.WebMercator)
+            if (ParentMap == null || !SupportedMapProjections.Contains(ParentMap.MapProjection.CrsId))
             {
                 TileMatrix = null;
                 Children.Clear();

MapControl/Shared/MapTileLayerBase.cs

@@ -189,6 +189,8 @@ namespace MapControl
             }
         }
 
+        public abstract IReadOnlyCollection<string> SupportedMapProjections { get; }
+
         protected bool IsBaseMapLayer => parentMap != null && parentMap.Children.Count > 0 && parentMap.Children[0] == this;
 
         protected void BeginLoadTiles(IEnumerable<Tile> tiles, string cacheName)

MapControl/Shared/WmsImageLayer.cs

@@ -16,6 +16,7 @@ using Microsoft.UI.Xaml;
 using Microsoft.UI.Xaml.Media;
 #elif AVALONIA
 using Avalonia;
+using Avalonia.Interactivity;
 #endif
 
 namespace MapControl
@@ -26,27 +27,24 @@ namespace MapControl
     public partial class WmsImageLayer : MapImageLayer
     {
         private static ILogger logger;
-        private static ILogger Logger => logger ??= ImageLoader.LoggerFactory?.CreateLogger<GroundOverlay>();
+        private static ILogger Logger => logger ??= ImageLoader.LoggerFactory?.CreateLogger(typeof(WmsImageLayer));
 
         public static readonly DependencyProperty ServiceUriProperty =
             DependencyPropertyHelper.Register<WmsImageLayer, Uri>(nameof(ServiceUri), null,
                 async (layer, oldValue, newValue) => await layer.UpdateImageAsync());
 
-        public static readonly DependencyProperty WmsStylesProperty =
+        public static readonly DependencyProperty RequestStylesProperty =
-            DependencyPropertyHelper.Register<WmsImageLayer, string>(nameof(WmsStyles), "",
+            DependencyPropertyHelper.Register<WmsImageLayer, string>(nameof(RequestStyles), "",
                 async (layer, oldValue, newValue) => await layer.UpdateImageAsync());
 
-        public static readonly DependencyProperty WmsLayersProperty =
+        public static readonly DependencyProperty RequestLayersProperty =
-            DependencyPropertyHelper.Register<WmsImageLayer, string>(nameof(WmsLayers), null,
+            DependencyPropertyHelper.Register<WmsImageLayer, string>(nameof(RequestLayers), null,
-                async (layer, oldValue, newValue) =>
+                async (layer, oldValue, newValue) => await layer.UpdateImageAsync());
+
+        public WmsImageLayer()
         {
-                    // Ignore property change from GetImageAsync when WmsLayers was null.
+            Loaded += OnLoaded;
-                    //
-                    if (oldValue != null)
-                    {
-                        await layer.UpdateImageAsync();
         }
-                });
 
         /// <summary>
         /// The base request URL. 
@@ -60,42 +58,30 @@ namespace MapControl
         /// <summary>
         /// Comma-separated sequence of requested WMS Styles. Default is an empty string.
         /// </summary>
-        public string WmsStyles
+        public string RequestStyles
         {
-            get => (string)GetValue(WmsStylesProperty);
+            get => (string)GetValue(RequestStylesProperty);
-            set => SetValue(WmsStylesProperty, value);
+            set => SetValue(RequestStylesProperty, value);
         }
 
         /// <summary>
-        /// Comma-separated sequence of WMS Layer names to be displayed. If not set, the first Layer is displayed.
+        /// Comma-separated sequence of WMS Layer names to be displayed. If not set, the default Layer is displayed.
         /// </summary>
-        public string WmsLayers
+        public string RequestLayers
         {
-            get => (string)GetValue(WmsLayersProperty);
+            get => (string)GetValue(RequestLayersProperty);
-            set => SetValue(WmsLayersProperty, value);
+            set => SetValue(RequestLayersProperty, value);
         }
 
         /// <summary>
-        /// Gets a list of all layer names returned by a GetCapabilities response.
+        /// Gets a collection of all Layer names available in a WMS.
         /// </summary>
-        public async Task<IEnumerable<string>> GetLayerNamesAsync()
+        public IReadOnlyCollection<string> AvailableLayers { get; private set; }
-        {
-            IEnumerable<string> layerNames = null;
 
-            var capabilities = await GetCapabilitiesAsync();
+        /// <summary>
-
+        /// Gets a collection of all CRSs supported by a WMS.
-            if (capabilities != null)
+        /// </summary>
-            {
+        public override IReadOnlyCollection<string> SupportedMapProjections => mapProjections;
-                var ns = capabilities.Name.Namespace;
-
-                layerNames = capabilities
-                    .Descendants(ns + "Layer")
-                    .Select(e => e.Element(ns + "Name")?.Value)
-                    .Where(n => !string.IsNullOrEmpty(n));
-            }
-
-            return layerNames;
-        }
 
         /// <summary>
         /// Loads an XElement from the URL returned by GetCapabilitiesRequestUri().
@@ -167,16 +153,6 @@ namespace MapControl
 
             try
             {
-                if (ServiceUri != null && ParentMap?.MapProjection != null)
-                {
-                    if (WmsLayers == null &&
-                        ServiceUri.OriginalString.IndexOf("LAYERS=", StringComparison.OrdinalIgnoreCase) < 0)
-                    {
-                        // Get first Layer from a GetCapabilities response.
-                        //
-                        WmsLayers = (await GetLayerNamesAsync())?.FirstOrDefault() ?? "";
-                    }
-
                 if (boundingBox.West >= -180d && boundingBox.East <= 180d ||
                     ParentMap.MapProjection.Type > MapProjectionType.NormalCylindrical)
                 {
@@ -211,7 +187,6 @@ namespace MapControl
                     }
                 }
             }
-            }
             catch (Exception ex)
             {
                 Logger?.LogError(ex, "GetImageAsync");
@@ -251,8 +226,8 @@ namespace MapControl
                     { "SERVICE", "WMS" },
                     { "VERSION", "1.3.0" },
                     { "REQUEST", "GetMap" },
-                    { "LAYERS", WmsLayers ?? "" },
+                    { "LAYERS", RequestLayers ?? "" },
-                    { "STYLES", WmsStyles ?? "" },
+                    { "STYLES", RequestStyles ?? "" },
                     { "FORMAT", "image/png" },
                     { "CRS", GetCrsValue() },
                     { "BBOX", GetBboxValue(boundingBox, bbox.Value) },
@@ -289,8 +264,8 @@ namespace MapControl
                     { "SERVICE", "WMS" },
                     { "VERSION", "1.3.0" },
                     { "REQUEST", "GetFeatureInfo" },
-                    { "LAYERS", WmsLayers ?? "" },
+                    { "LAYERS", RequestLayers ?? "" },
-                    { "STYLES", WmsStyles ?? "" },
+                    { "STYLES", RequestStyles ?? "" },
                     { "FORMAT", "image/png" },
                     { "INFO_FORMAT", format },
                     { "CRS", GetCrsValue() },
@@ -312,25 +287,25 @@ namespace MapControl
         protected virtual string GetCrsValue()
         {
             var projection = ParentMap.MapProjection;
-            var crsId = projection.CrsId;
+            var crs = projection.CrsId;
 
-            if (crsId.StartsWith("AUTO2:") || crsId.StartsWith("AUTO:"))
+            if (crs.StartsWith("AUTO2:") || crs.StartsWith("AUTO:"))
             {
-                crsId = string.Format(CultureInfo.InvariantCulture, "{0},1,{1},{2}", crsId, projection.Center.Longitude, projection.Center.Latitude);
+                crs = string.Format(CultureInfo.InvariantCulture, "{0},1,{1},{2}", crs, projection.Center.Longitude, projection.Center.Latitude);
             }
 
-            return crsId;
+            return crs;
         }
 
         protected virtual string GetBboxValue(BoundingBox boundingBox, Rect mapBoundingBox)
         {
-            var crsId = ParentMap.MapProjection.CrsId;
+            var crs = ParentMap.MapProjection.CrsId;
             string format;
             double x1, y1, x2, y2;
 
-            if (crsId == "CRS:84" || crsId == "EPSG:4326")
+            if (crs == "CRS:84" || crs == "EPSG:4326")
             {
-                format = crsId == "CRS:84" ? "{0:F8},{1:F8},{2:F8},{3:F8}" : "{1:F8},{0:F8},{3:F8},{2:F8}";
+                format = crs == "CRS:84" ? "{0:F8},{1:F8},{2:F8},{3:F8}" : "{1:F8},{0:F8},{3:F8},{2:F8}";
                 x1 = boundingBox.West;
                 y1 = boundingBox.South;
                 x2 = boundingBox.East;
@@ -366,5 +341,48 @@ namespace MapControl
 
             return uri.Replace(" ", "%20");
         }
+
+        private List<string> mapProjections;
+
+        private async void OnLoaded(object sender, RoutedEventArgs e)
+        {
+            Loaded -= OnLoaded;
+
+            if (AvailableLayers == null && ServiceUri != null)
+            {
+                var capabilities = await GetCapabilitiesAsync();
+
+                if (capabilities != null)
+                {
+                    var ns = capabilities.Name.Namespace;
+                    var capability = capabilities.Element(ns + "Capability");
+
+                    mapProjections = capability
+                        .Element(ns + "Layer")
+                        .Descendants(ns + "CRS")
+                        .Select(e => e.Value)
+                        .ToList();
+
+                    var layerNames = capability
+                        .Descendants(ns + "Layer")
+                        .Select(e => e.Element(ns + "Name")?.Value)
+                        .Where(n => !string.IsNullOrEmpty(n))
+                        .ToList();
+
+                    AvailableLayers = layerNames;
+
+                    if (layerNames.Count > 0 &&
+                        RequestLayers == null &&
+                        ServiceUri.OriginalString.IndexOf("LAYERS=", StringComparison.OrdinalIgnoreCase) < 0)
+                    {
+                        RequestLayers = layerNames[0];
+                    }
+                    else
+                    {
+                        await UpdateImageAsync();
+                    }
+                }
+            }
+        }
     }
 }

MapControl/Shared/WmtsTileLayer.cs

@@ -23,7 +23,7 @@ namespace MapControl
     public partial class WmtsTileLayer : MapTileLayerBase
     {
         private static ILogger logger;
-        private static ILogger Logger => logger ??= ImageLoader.LoggerFactory?.CreateLogger<GroundOverlay>();
+        private static ILogger Logger => logger ??= ImageLoader.LoggerFactory?.CreateLogger(typeof(WmtsTileLayer));
 
         public static readonly DependencyProperty CapabilitiesUriProperty =
             DependencyPropertyHelper.Register<WmtsTileLayer, Uri>(nameof(CapabilitiesUri), null,
@@ -68,11 +68,19 @@ namespace MapControl
             set => SetValue(PreferredTileMatrixSetsProperty, value);
         }
 
-        public IEnumerable<WmtsTileMatrixLayer> ChildLayers => Children.Cast<WmtsTileMatrixLayer>();
+        /// <summary>
-
+        /// Gets a dictionary of all tile matrix sets supported by a WMTS, with their CRS as dictionary key.
+        /// </summary>
         public Dictionary<string, WmtsTileMatrixSet> TileMatrixSets { get; } = [];
 
-        protected virtual WmtsTileSource CreateTileSource(string uriTemplate) => new WmtsTileSource { UriTemplate = uriTemplate };
+        /// <summary>
+        /// Gets a collection of all CRSs supported by a WMTS.
+        /// </summary>
+        public override IReadOnlyCollection<string> SupportedMapProjections => TileMatrixSets.Keys;
+
+        protected IEnumerable<WmtsTileMatrixLayer> ChildLayers => Children.Cast<WmtsTileMatrixLayer>();
+
+        protected virtual WmtsTileSource CreateTileSource(string uriTemplate) => new() { UriTemplate = uriTemplate };
 
         protected override Size MeasureOverride(Size availableSize)
         {
@@ -192,10 +200,10 @@ namespace MapControl
                     var capabilities = await WmtsCapabilities.ReadCapabilitiesAsync(CapabilitiesUri, Layer);
 
                     foreach (var tileMatrixSet in capabilities.TileMatrixSets
-                        .Where(s => !TileMatrixSets.ContainsKey(s.SupportedCrs) ||
+                        .Where(s => !TileMatrixSets.ContainsKey(s.SupportedMapProjection) ||
                                     PreferredTileMatrixSets != null && PreferredTileMatrixSets.Contains(s.Identifier)))
                     {
-                        TileMatrixSets[tileMatrixSet.SupportedCrs] = tileMatrixSet;
+                        TileMatrixSets[tileMatrixSet.SupportedMapProjection] = tileMatrixSet;
                     }
 
                     Layer = capabilities.Layer;

MapControl/Shared/WmtsTileMatrixSet.cs

@@ -6,16 +6,16 @@ namespace MapControl
 {
     public class WmtsTileMatrixSet
     {
-        public WmtsTileMatrixSet(string identifier, string supportedCrs, IEnumerable<WmtsTileMatrix> tileMatrixes)
+        public WmtsTileMatrixSet(string identifier, string supportedMapProjection, IEnumerable<WmtsTileMatrix> tileMatrixes)
         {
             if (string.IsNullOrEmpty(identifier))
             {
                 throw new ArgumentException($"The {nameof(identifier)} argument must not be null or empty.", nameof(identifier));
             }
 
-            if (string.IsNullOrEmpty(supportedCrs))
+            if (string.IsNullOrEmpty(supportedMapProjection))
             {
-                throw new ArgumentException($"The {nameof(supportedCrs)} argument must not be null or empty.", nameof(supportedCrs));
+                throw new ArgumentException($"The {nameof(supportedMapProjection)} argument must not be null or empty.", nameof(supportedMapProjection));
             }
 
             if (tileMatrixes == null || !tileMatrixes.Any())
@@ -24,12 +24,12 @@ namespace MapControl
             }
 
             Identifier = identifier;
-            SupportedCrs = supportedCrs;
+            SupportedMapProjection = supportedMapProjection;
             TileMatrixes = tileMatrixes.OrderBy(m => m.Scale).ToList();
         }
 
         public string Identifier { get; }
-        public string SupportedCrs { get; }
+        public string SupportedMapProjection { get; }
         public IList<WmtsTileMatrix> TileMatrixes { get; }
     }
 }

SampleApps/ProjectionDemo/MainWindow.xaml.cs

@@ -28,7 +28,7 @@ namespace ProjectionDemo
                 new WmsImageLayer
                 {
                     ServiceUri = new Uri("http://ows.terrestris.de/osm/service"),
-                    WmsLayers = "OSM-WMS"
+                    RequestLayers = "OSM-WMS"
                 });
 
             viewModel.Layers.Add(
@@ -36,7 +36,7 @@ namespace ProjectionDemo
                 new WmsImageLayer
                 {
                     ServiceUri = new Uri("https://sgx.geodatenzentrum.de/wms_topplus_open"),
-                    WmsLayers = "web"
+                    RequestLayers = "web"
                 });
 
             viewModel.Layers.Add(
@@ -44,7 +44,7 @@ namespace ProjectionDemo
                 new WmsImageLayer
                 {
                     ServiceUri = new Uri("https://sgx.geodatenzentrum.de/wms_basemapde"),
-                    WmsLayers = "de_basemapde_web_raster_farbe"
+                    RequestLayers = "de_basemapde_web_raster_farbe"
                 });
 
             viewModel.Layers.Add(
@@ -52,7 +52,7 @@ namespace ProjectionDemo
                 new WmsImageLayer
                 {
                     ServiceUri = new Uri("https://geoportal.wiesbaden.de/cgi-bin/mapserv.fcgi?map=d:/openwimap/umn/map/orthophoto/orthophotos.map"),
-                    WmsLayers = "orthophoto2023"
+                    RequestLayers = "orthophoto2023"
                 });
 
             viewModel.CurrentProjection = viewModel.Projections[0];