Update comments

MapControl/Shared/GeoImage.cs

@@ -94,7 +94,8 @@ namespace MapControl
 
                     image.RenderTransform = new RotateTransform { Angle = -rotation };
 
-                    // effective unrotated transform
+                    // Calculate effective unrotated transform.
+                    //
                     transform.M11 = Math.Sqrt(transform.M11 * transform.M11 + transform.M12 * transform.M12);
                     transform.M22 = -Math.Sqrt(transform.M22 * transform.M22 + transform.M21 * transform.M21);
                     transform.M12 = 0;

MapControl/Shared/GroundOverlay.cs

@@ -114,7 +114,8 @@ namespace MapControl
                     overlay.RenderTransform = new RotateTransform { Angle = -imageOverlay.LatLonBox.Rotation };
                     overlay.RenderTransformOrigin = new Point(0.5, 0.5);
 
-                    // additional Panel for map rotation, see MapPanel.ArrangeElementWithBoundingBox
+                    // Additional Panel for map rotation, see MapPanel.ArrangeElementWithBoundingBox.
+                    //
                     var panel = new Grid { UseLayoutRounding = false };
                     panel.Children.Add(overlay);
                     overlay = panel;

MapControl/Shared/ImageLoader.cs

@@ -89,7 +89,7 @@ namespace MapControl
                     {
                         byte[] buffer = null;
 
-                        // check for possibly unavailable Bing Maps tile
+                        // Check for possibly unavailable Bing Maps tile.
                         //
                         if (!responseMessage.Headers.TryGetValues("X-VE-Tile-Info", out IEnumerable<string> tileInfo) ||
                             !tileInfo.Contains("no-tile"))

MapControl/Shared/MapBase.cs

@@ -343,7 +343,9 @@ namespace MapControl
             }
             else
             {
-                TranslateMap(translation); // more precise
+                // More accurate than SetTransformCenter.
+                //
+                TranslateMap(translation);
             }
         }
 
@@ -764,7 +766,8 @@ namespace MapControl
 
                         if (resetTransformCenter)
                         {
-                            // check if transform center moved across the dateline
+                            // Check if transform center moved across the dateline.
+                            //
                             transformCenterChanged = Math.Abs(center.Longitude - transformCenter.Longitude) > 180d;
 
                             ResetTransformCenter();
@@ -783,7 +786,8 @@ namespace MapControl
 
                 SetViewScale(ViewTransform.Scale);
 
-                // check if view center moved across the dateline
+                // Check if view center moved across the dateline.
+                //
                 transformCenterChanged = transformCenterChanged || Math.Abs(Center.Longitude - centerLongitude) > 180d;
                 centerLongitude = Center.Longitude;
 

MapControl/Shared/MapGraticule.cs

@@ -114,7 +114,7 @@ namespace MapControl
             {
                 if (!rotation.HasValue)
                 {
-                    // get rotation from second location with same latitude
+                    // Get rotation from second location with same latitude.
                     //
                     var pos = ParentMap.LocationToView(
                         new Location(location.Latitude, location.Longitude + 10d / PixelPerLongitudeDegree(location)));

MapControl/Shared/MapImageLayer.cs

@@ -180,7 +180,7 @@ namespace MapControl
         {
             if (updateInProgress)
             {
-                // update image on next tick, start timer if not running
+                // Update image on next tick, start timer if not running.
                 //
                 updateTimer.Run();
             }

MapControl/Shared/MapItemsControl.cs

@@ -61,7 +61,9 @@ namespace MapControl
 
         protected override Size ArrangeOverride(Size bounds)
         {
-            if (mapTransform != null) // property in use, e.g. as source of a Binding
+            // If MapTransform is used, update its Matrix property.
+            //
+            if (mapTransform != null)
             {
                 var parentMap = (VisualTreeHelper.GetParent(this) as MapPanel)?.ParentMap;
 
@@ -184,7 +186,7 @@ namespace MapControl
 
             if (SelectionMode == SelectionMode.Single)
             {
-                // Single -> set only SelectedItem
+                // Single -> set only SelectedItem.
 
                 if (SelectedItem != item)
                 {
@@ -197,7 +199,7 @@ namespace MapControl
             }
             else if (SelectionMode == SelectionMode.Multiple || controlKey)
             {
-                // Multiple or Extended with Ctrl -> toggle item in SelectedItems
+                // Multiple or Extended with Ctrl -> toggle item in SelectedItems.
 
                 if (SelectedItems.Contains(item))
                 {
@@ -210,7 +212,7 @@ namespace MapControl
             }
             else if (shiftKey && SelectedItem != null)
             {
-                // Extended with Shift -> select items in view rectangle
+                // Extended with Shift -> select items in view rectangle.
 
                 var p1 = MapPanel.GetViewPosition(ContainerFromItem(SelectedItem));
                 var p2 = MapPanel.GetViewPosition(mapItem);
@@ -222,7 +224,7 @@ namespace MapControl
             }
             else if (SelectedItem != item)
             {
-                // Extended without Control or Shift -> set selected item
+                // Extended without Control or Shift -> set selected item.
 
                 SelectedItem = item;
             }

MapControl/Shared/MapTileLayer.cs

@@ -108,7 +108,7 @@ namespace MapControl
             {
                 foreach (var tile in Tiles)
                 {
-                    // arrange tiles relative to XMin/YMin
+                    // Arrange tiles relative to XMin/YMin.
                     //
                     var tileSize = TileSize << (TileMatrix.ZoomLevel - tile.ZoomLevel);
                     var x = tileSize * tile.X - TileSize * TileMatrix.XMin;
@@ -162,7 +162,7 @@ namespace MapControl
         {
             if (TileMatrix != null)
             {
-                // tile matrix origin in pixels
+                // Tile matrix origin in pixels.
                 //
                 var tileMatrixOrigin = new Point(TileSize * TileMatrix.XMin, TileSize * TileMatrix.YMin);
 
@@ -175,15 +175,17 @@ namespace MapControl
 
         private bool SetTileMatrix()
         {
-            var tileMatrixZoomLevel = (int)Math.Floor(ParentMap.ZoomLevel - ZoomLevelOffset + 0.001); // avoid rounding issues
+            // Add 0.001 to avoid rounding issues.
+            //
+            var tileMatrixZoomLevel = (int)Math.Floor(ParentMap.ZoomLevel - ZoomLevelOffset + 0.001);
 
             var tileMatrixScale = ViewTransform.ZoomLevelToScale(tileMatrixZoomLevel);
 
-            // bounds in tile pixels from view size
+            // Bounds in tile pixels from view size.
             //
             var bounds = ParentMap.ViewTransform.GetTileMatrixBounds(tileMatrixScale, MapTopLeft, ParentMap.RenderSize);
 
-            // tile X and Y bounds
+            // Tile X and Y bounds.
             //
             var xMin = (int)Math.Floor(bounds.X / TileSize);
             var yMin = (int)Math.Floor(bounds.Y / TileSize);

MapControl/Shared/ViewTransform.cs

@@ -93,13 +93,13 @@ namespace MapControl
 
             transform.Rotate(Rotation);
 
-            // tile matrix origin in map coordinates
+            // Tile matrix origin in map coordinates.
             //
             var mapOrigin = new Point(
                 tileMatrixTopLeft.X + tileMatrixOrigin.X / tileMatrixScale,
                 tileMatrixTopLeft.Y - tileMatrixOrigin.Y / tileMatrixScale);
 
-            // tile matrix origin in view coordinates
+            // Tile matrix origin in view coordinates.
             //
             var viewOrigin = MapToView(mapOrigin);
 
@@ -115,17 +115,17 @@ namespace MapControl
 
             transform.Rotate(-Rotation);
 
-            // view origin in map coordinates
+            // View origin in map coordinates.
             //
             var origin = ViewToMap(new Point());
 
-            // translate origin to tile matrix origin in pixels
+            // Translate origin to tile matrix origin in pixels.
             //
             transform.Translate(
                 tileMatrixScale * (origin.X - tileMatrixTopLeft.X),
                 tileMatrixScale * (tileMatrixTopLeft.Y - origin.Y));
 
-            // transform view bounds to tile pixel bounds
+            // Transform view bounds to tile pixel bounds.
             //
             return new MatrixTransform { Matrix = transform }
                 .TransformBounds(new Rect(0d, 0d, viewSize.Width, viewSize.Height));

MapControl/Shared/WmsImageLayer.cs

@@ -37,7 +37,9 @@ namespace MapControl
             new PropertyMetadata(null,
                 async (o, e) =>
                 {
-                    if (e.OldValue != null) // ignore property change from GetImageAsync
+                    // Ignore property change from GetImageAsync, when Layers was null.
+                    //
+                    if (e.OldValue != null)
                     {
                         await ((WmsImageLayer)o).UpdateImageAsync();
                     }
@@ -176,7 +178,9 @@ namespace MapControl
                 if (Layers == null &&
                     ServiceUri.ToString().IndexOf("LAYERS=", StringComparison.OrdinalIgnoreCase) < 0)
                 {
-                    Layers = (await GetLayerNamesAsync())?.FirstOrDefault() ?? ""; // get first Layer from Capabilities
+                    // Get first Layer from a GetCapabilities response.
+                    //
+                    Layers = (await GetLayerNamesAsync())?.FirstOrDefault() ?? "";
                 }
 
                 if (boundingBox.West >= -180d && boundingBox.East <= 180d ||

MapControl/Shared/WmtsTileLayer.cs

@@ -112,20 +112,26 @@ namespace MapControl
 
         private bool UpdateChildLayers(WmtsTileMatrixSet tileMatrixSet)
         {
-            var maxScale = 1.001 * ParentMap.ViewTransform.Scale; // avoid rounding issues
+            // Multiply scale by 1.001 to avoid rounding issues.
+            //
+            var maxScale = 1.001 * ParentMap.ViewTransform.Scale;
 
-            // show all WmtsTileMatrix layers with Scale <= maxScale, at least the first layer
+            // Show all WmtsTileMatrix layers with Scale <= maxScale, at least the first layer.
             //
             var currentMatrixes = tileMatrixSet.TileMatrixes
                 .Where((matrix, i) => i == 0 || matrix.Scale <= maxScale)
                 .ToList();
 
-            if (!IsBaseMapLayer) // show only the last layer
+            if (!IsBaseMapLayer)
             {
+                // Show only the last layer.
+                //
                 currentMatrixes = currentMatrixes.Skip(currentMatrixes.Count - 1).ToList();
             }
             else if (currentMatrixes.Count > MaxBackgroundLevels + 1)
             {
+                // Show not more than MaxBackgroundLevels + 1 layers.
+                //
                 currentMatrixes = currentMatrixes.Skip(currentMatrixes.Count - MaxBackgroundLevels - 1).ToList();
             }
 

MapControl/Shared/WmtsTileMatrixLayer.cs

@@ -21,7 +21,7 @@ namespace MapControl
 {
     public class WmtsTileMatrixLayer : Panel
     {
-        // zoomLevel is index of tileMatrix in a WmtsTileMatrixSet.TileMatrixes list
+        // zoomLevel is index of tileMatrix in a WmtsTileMatrixSet.TileMatrixes list.
         //
         public WmtsTileMatrixLayer(WmtsTileMatrix tileMatrix, int zoomLevel)
         {
@@ -38,7 +38,7 @@ namespace MapControl
 
         public void SetRenderTransform(ViewTransform viewTransform)
         {
-            // tile matrix origin in pixels
+            // Tile matrix origin in pixels.
             //
             var tileMatrixOrigin = new Point(WmtsTileMatrix.TileWidth * TileMatrix.XMin, WmtsTileMatrix.TileHeight * TileMatrix.YMin);
 
@@ -48,24 +48,24 @@ namespace MapControl
 
         public bool UpdateTiles(ViewTransform viewTransform, Size viewSize)
         {
-            // bounds in tile pixels from view size
+            // Bounds in tile pixels from view size.
             //
             var bounds = viewTransform.GetTileMatrixBounds(WmtsTileMatrix.Scale, WmtsTileMatrix.TopLeft, viewSize);
 
-            // tile X and Y bounds
+            // Tile X and Y bounds.
             //
             var xMin = (int)Math.Floor(bounds.X / WmtsTileMatrix.TileWidth);
             var yMin = (int)Math.Floor(bounds.Y / WmtsTileMatrix.TileHeight);
             var xMax = (int)Math.Floor((bounds.X + bounds.Width) / WmtsTileMatrix.TileWidth);
             var yMax = (int)Math.Floor((bounds.Y + bounds.Height) / WmtsTileMatrix.TileHeight);
 
-            // total tile matrix width in meters
+            // Total tile matrix width in meters.
             //
             var totalWidth = WmtsTileMatrix.MatrixWidth * WmtsTileMatrix.TileWidth / WmtsTileMatrix.Scale;
 
             if (Math.Abs(totalWidth - 360d * MapProjection.Wgs84MeterPerDegree) > 1d)
             {
-                // no full longitudinal coverage, restrict x index
+                // No full longitudinal coverage, restrict x index.
                 //
                 xMin = Math.Max(xMin, 0);
                 xMax = Math.Min(Math.Max(xMax, 0), WmtsTileMatrix.MatrixWidth - 1);
@@ -77,7 +77,7 @@ namespace MapControl
             if (TileMatrix.XMin == xMin && TileMatrix.YMin == yMin &&
                 TileMatrix.XMax == xMax && TileMatrix.YMax == yMax)
             {
-                // no change of the TileMatrix and the Tiles collection
+                // No change of the TileMatrix and the Tiles collection.
                 //
                 return false;
             }
@@ -122,7 +122,7 @@ namespace MapControl
         {
             foreach (var tile in Tiles)
             {
-                // arrange tiles relative to XMin/YMin
+                // Arrange tiles relative to XMin/YMin.
                 //
                 var x = WmtsTileMatrix.TileWidth * (tile.X - TileMatrix.XMin);
                 var y = WmtsTileMatrix.TileHeight * (tile.Y - TileMatrix.YMin);

MapControl/WPF/Map.WPF.cs

@@ -101,7 +101,9 @@ namespace MapControl
 
         private void OnMouseWheel(object sender, MouseWheelEventArgs e)
         {
-            mouseWheelDelta += e.Delta / 120d; // standard mouse wheel delta
+            // Standard mouse wheel delta value is 120.
+            //
+            mouseWheelDelta += e.Delta / 120d;
 
             if (Math.Abs(mouseWheelDelta) >= 1d)
             {

MapControl/WPF/MapOverlay.WPF.cs

@@ -61,7 +61,8 @@ namespace MapControl
         {
             base.OnInitialized(e);
 
-            // If this.Stroke is not explicitly set, bind it to this.Foreground
+            // If this.Stroke is not explicitly set, bind it to this.Foreground.
+            //
             this.SetBindingOnUnsetProperty(StrokeProperty, this, ForegroundProperty, nameof(Foreground));
         }
 

MapControl/WPF/MapPath.WPF.cs

@@ -27,7 +27,9 @@ namespace MapControl
 
         private static void DataPropertyChanged(DependencyObject obj, DependencyPropertyChangedEventArgs e)
         {
-            if (e.NewValue != null && !ReferenceEquals(e.NewValue, e.OldValue)) // Data is actually a new Geometry
+            // Check if Data is actually a new Geometry.
+            //
+            if (e.NewValue != null && !ReferenceEquals(e.NewValue, e.OldValue))
             {
                 var path = (MapPath)obj;
                 var data = (Geometry)e.NewValue;

MapControl/WinUI/ImageLoader.WinUI.cs

@@ -40,7 +40,9 @@ namespace MapControl
         {
             using (var stream = new MemoryStream(buffer))
             {
-                return await LoadImageAsync(stream); // await before closing stream
+                // Must await method before closing the stream.
+                //
+                return await LoadImageAsync(stream);
             }
         }
 

MapControl/WinUI/Map.WinUI.cs

@@ -58,7 +58,9 @@ namespace MapControl
             {
                 var point = e.GetCurrentPoint(this);
 
-                mouseWheelDelta += point.Properties.MouseWheelDelta / 120d; // standard mouse wheel delta
+                // Standard mouse wheel delta value is 120.
+                //
+                mouseWheelDelta += point.Properties.MouseWheelDelta / 120d;
 
                 if (Math.Abs(mouseWheelDelta) >= 1d)
                 {

MapControl/WinUI/MapBase.WinUI.cs

@@ -56,7 +56,8 @@ namespace MapControl
 
         public MapBase()
         {
-            // set Background by Style to enable resetting by ClearValue in MapLayerPropertyChanged
+            // Set Background by Style to enable resetting by ClearValue in MapLayerPropertyChanged.
+            //
             var style = new Style(typeof(MapBase));
             style.Setters.Add(new Setter(BackgroundProperty, new SolidColorBrush(Colors.White)));
             Style = style;

MapControl/WinUI/MapContentControl.WinUI.cs

@@ -57,13 +57,16 @@ namespace MapControl
 
             if (parentMap != null)
             {
-                // If this.Background is not explicitly set, bind it to parentMap.Background
+                // If this.Background is not explicitly set, bind it to parentMap.Background.
+                //
                 this.SetBindingOnUnsetProperty(BackgroundProperty, parentMap, Panel.BackgroundProperty, nameof(Background));
 
-                // If this.Foreground is not explicitly set, bind it to parentMap.Foreground
+                // If this.Foreground is not explicitly set, bind it to parentMap.Foreground.
+                //
                 this.SetBindingOnUnsetProperty(ForegroundProperty, parentMap, MapBase.ForegroundProperty, nameof(Foreground));
 
-                // If this.BorderBrush is not explicitly set, bind it to parentMap.Foreground
+                // If this.BorderBrush is not explicitly set, bind it to parentMap.Foreground.
+                //
                 this.SetBindingOnUnsetProperty(BorderBrushProperty, parentMap, MapBase.ForegroundProperty, nameof(Foreground));
             }
         }

MapControl/WinUI/MapOverlay.WinUI.cs

@@ -66,10 +66,12 @@ namespace MapControl
         {
             if (map != null)
             {
-                // If this.Forground is not explicitly set, bind it to map.Foreground
+                // If this.Forground is not explicitly set, bind it to map.Foreground.
+                //
                 this.SetBindingOnUnsetProperty(ForegroundProperty, map, MapBase.ForegroundProperty, nameof(Foreground));
 
-                // If this.Stroke is not explicitly set, bind it to this.Foreground
+                // If this.Stroke is not explicitly set, bind it to this.Foreground.
+                //
                 this.SetBindingOnUnsetProperty(StrokeProperty, this, ForegroundProperty, nameof(Foreground));
             }