Add documentation.

src/Avalonia.Visuals/Media/Imaging/Bitmap.cs

@@ -11,18 +11,41 @@ namespace Avalonia.Media.Imaging
     /// </summary>
     public class Bitmap : IBitmap
     {
+        /// <summary>
+        /// Loads a Bitmap from a stream and decodes at the desired width. Aspect ratio is maintained.
+        /// This is more efficient than loading and then resizing.
+        /// </summary>
+        /// <param name="stream">The stream to read the bitmap from. This can be any supported image format.</param>
+        /// <param name="width">The desired width of the resulting bitmap.</param>
+        /// <param name="interpolationMode">The <see cref="BitmapInterpolationMode"/> to use should any scaling be required.</param>
+        /// <returns>An instance of the <see cref="Bitmap"/> class.</returns>
         public static Bitmap DecodeToWidth(Stream stream, int width, BitmapInterpolationMode interpolationMode = BitmapInterpolationMode.HighQuality)
         {
             IPlatformRenderInterface factory = AvaloniaLocator.Current.GetService<IPlatformRenderInterface>();
             return new Bitmap(factory.LoadBitmapToWidth(stream, width, interpolationMode));
         }
 
+        /// <summary>
+        /// Loads a Bitmap from a stream and decodes at the desired height. Aspect ratio is maintained.
+        /// This is more efficient than loading and then resizing.
+        /// </summary>
+        /// <param name="stream">The stream to read the bitmap from. This can be any supported image format.</param>
+        /// <param name="height">The desired height of the resulting bitmap.</param>
+        /// <param name="interpolationMode">The <see cref="BitmapInterpolationMode"/> to use should any scaling be required.</param>
+        /// <returns>An instance of the <see cref="Bitmap"/> class.</returns>
         public static Bitmap DecodeToHeight(Stream stream, int height, BitmapInterpolationMode interpolationMode = BitmapInterpolationMode.HighQuality)
         {
             IPlatformRenderInterface factory = AvaloniaLocator.Current.GetService<IPlatformRenderInterface>();
             return new Bitmap(factory.LoadBitmapToHeight(stream, height, interpolationMode));
         }
 
+        /// <summary>
+        /// Creates a Bitmap from another Bitmap scaled to a specified size.
+        /// </summary>
+        /// <param name="src">The source bitmap.</param>
+        /// <param name="destinationSize">The destination size.</param>
+        /// <param name="interpolationMode">The <see cref="BitmapInterpolationMode"/> to use should any scaling be required.</param>
+        /// <returns>An instance of the <see cref="Bitmap"/> class.</returns>
         public static Bitmap CreateScaledBitmap(Bitmap src, PixelSize destinationSize, BitmapInterpolationMode interpolationMode = BitmapInterpolationMode.HighQuality)
         {
             IPlatformRenderInterface factory = AvaloniaLocator.Current.GetService<IPlatformRenderInterface>();
@@ -57,7 +80,7 @@ namespace Avalonia.Media.Imaging
         {
             PlatformImpl = impl.Clone();
         }
-        
+
         /// <summary>
         /// Initializes a new instance of the <see cref="Bitmap"/> class.
         /// </summary>
@@ -66,7 +89,7 @@ namespace Avalonia.Media.Imaging
         {
             PlatformImpl = RefCountable.Create(impl);
         }
-        
+
         /// <inheritdoc/>
         public virtual void Dispose()
         {

src/Avalonia.Visuals/Platform/IPlatformRenderInterface.cs

@@ -91,7 +91,7 @@ namespace Avalonia.Platform
         /// </summary>
         /// <param name="fileName">The filename of the bitmap.</param>        
         /// <returns>An <see cref="IBitmapImpl"/>.</returns>
-        IBitmapImpl LoadBitmap(string fileName);        
+        IBitmapImpl LoadBitmap(string fileName);
 
         /// <summary>
         /// Loads a bitmap implementation from a file..
@@ -101,16 +101,20 @@ namespace Avalonia.Platform
         IBitmapImpl LoadBitmap(Stream stream);
 
         /// <summary>
-        /// Loads a bitmap implementation from a file..
+        /// Loads a bitmap implementation from a stream to a specified width maintaining aspect ratio.
         /// </summary>
-        /// <param name="stream">The stream to read the bitmap from.</param>        
+        /// <param name="stream">The stream to read the bitmap from.</param> 
+        /// <param name="width">The desired width of the resulting bitmap.</param>
+        /// <param name="interpolationMode">The <see cref="BitmapInterpolationMode"/> to use should resizing be required.</param>
         /// <returns>An <see cref="IBitmapImpl"/>.</returns>
         IBitmapImpl LoadBitmapToWidth(Stream stream, int width, BitmapInterpolationMode interpolationMode = BitmapInterpolationMode.HighQuality);
 
         /// <summary>
-        /// Loads a bitmap implementation from a file..
+        /// Loads a bitmap implementation from a stream to a specified height maintaining aspect ratio.
         /// </summary>
-        /// <param name="stream">The stream to read the bitmap from.</param>        
+        /// <param name="stream">The stream to read the bitmap from.</param> 
+        /// <param name="height">The desired height of the resulting bitmap.</param>
+        /// <param name="interpolationMode">The <see cref="BitmapInterpolationMode"/> to use should resizing be required.</param>
         /// <returns>An <see cref="IBitmapImpl"/>.</returns>
         IBitmapImpl LoadBitmapToHeight(Stream stream, int height, BitmapInterpolationMode interpolationMode = BitmapInterpolationMode.HighQuality);
 

src/Skia/Avalonia.Skia/ImmutableBitmap.cs

@@ -41,7 +41,7 @@ namespace Avalonia.Skia
         }
 
         public ImmutableBitmap(ImmutableBitmap src, PixelSize destinationSize, BitmapInterpolationMode interpolationMode)
-        {            
+        {
             SKImageInfo info = new SKImageInfo(destinationSize.Width, destinationSize.Height, SKColorType.Bgra8888);
             SKImage output = SKImage.Create(info);
             src._image.ScalePixels(output.PeekPixels(), interpolationMode.ToSKFilterQuality());

src/Skia/Avalonia.Skia/PlatformRenderInterface.cs

@@ -80,6 +80,7 @@ namespace Avalonia.Skia
             return new StreamGeometryImpl();
         }
 
+        /// <inheritdoc />
         public IBitmapImpl LoadBitmap(string fileName)
         {
             using (var stream = File.OpenRead(fileName))
@@ -88,27 +89,31 @@ namespace Avalonia.Skia
             }
         }
 
+        /// <inheritdoc />
         public IBitmapImpl LoadBitmap(Stream stream)
         {
             return new ImmutableBitmap(stream);
         }
 
+        /// <inheritdoc />
+        public IBitmapImpl LoadBitmap(PixelFormat format, IntPtr data, PixelSize size, Vector dpi, int stride)
+        {
+            return new ImmutableBitmap(size, dpi, stride, format, data);
+        }
+
+        /// <inheritdoc />
         public IBitmapImpl LoadBitmapToWidth(Stream stream, int width, BitmapInterpolationMode interpolationMode = BitmapInterpolationMode.HighQuality)
         {
             return new ImmutableBitmap(stream, width, true, interpolationMode);
         }
 
+        /// <inheritdoc />
         public IBitmapImpl LoadBitmapToHeight(Stream stream, int height, BitmapInterpolationMode interpolationMode = BitmapInterpolationMode.HighQuality)
         {
             return new ImmutableBitmap(stream, height, false, interpolationMode);
         }
 
         /// <inheritdoc />
-        public IBitmapImpl LoadBitmap(PixelFormat format, IntPtr data, PixelSize size, Vector dpi, int stride)
-        {
-            return new ImmutableBitmap(size, dpi, stride, format, data);
-        }
-
         public IBitmapImpl ResizeBitmap(IBitmapImpl bitmapImpl, PixelSize destinationSize, BitmapInterpolationMode interpolationMode = BitmapInterpolationMode.HighQuality)
         {
             if (bitmapImpl is ImmutableBitmap ibmp)

src/Windows/Avalonia.Direct2D1/Direct2D1Platform.cs

@@ -181,31 +181,37 @@ namespace Avalonia.Direct2D1
         public IGeometryImpl CreateRectangleGeometry(Rect rect) => new RectangleGeometryImpl(rect);
         public IStreamGeometryImpl CreateStreamGeometry() => new StreamGeometryImpl();
 
+        /// <inheritdoc />
         public IBitmapImpl LoadBitmap(string fileName)
         {
             return new WicBitmapImpl(fileName);
         }
 
+        /// <inheritdoc />
         public IBitmapImpl LoadBitmap(Stream stream)
         {
             return new WicBitmapImpl(stream);
         }
 
+        /// <inheritdoc />
         public IBitmapImpl LoadBitmapToWidth(Stream stream, int width, BitmapInterpolationMode interpolationMode = BitmapInterpolationMode.HighQuality)
         {
             throw new NotImplementedException();
         }
 
+        /// <inheritdoc />
         public IBitmapImpl LoadBitmapToHeight(Stream stream, int height, BitmapInterpolationMode interpolationMode = BitmapInterpolationMode.HighQuality)
         {
             throw new NotImplementedException();
         }
 
+        /// <inheritdoc />
         public IBitmapImpl ResizeBitmap(IBitmapImpl bitmapImpl, PixelSize destinationSize, BitmapInterpolationMode interpolationMode = BitmapInterpolationMode.HighQuality)
         {
             throw new NotImplementedException();
         }
 
+        /// <inheritdoc />
         public IBitmapImpl LoadBitmap(PixelFormat format, IntPtr data, PixelSize size, Vector dpi, int stride)
         {
             return new WicBitmapImpl(format, data, size, dpi, stride);