Merge pull request #13070 from Youssef1313/render-target-bitmap

fix: Fix rendering of RenderTargetBitmap

src/Uno.UI.Composition/Composition/SkiaCompositionSurface.skia.cs

@@ -32,9 +32,7 @@ namespace Windows.UI.Composition
 			{
 				using var codec = SKCodec.Create(stream);
 
-				var info = codec.Info;
-
-				var bitmap = new SKBitmap(actualTargetWidth, actualTargetHeight, info.ColorType, info.IsOpaque ? SKAlphaType.Opaque : SKAlphaType.Premul);
+				var bitmap = new SKBitmap(actualTargetWidth, actualTargetHeight, SKColorType.Bgra8888, SKAlphaType.Premul);
 
 				var result = codec.GetPixels(bitmap.Info, bitmap.GetPixels());
 

src/Uno.UI.Composition/Composition/SkiaExtensions.skia.cs

@@ -97,5 +97,30 @@ namespace Windows.UI.Composition
 
 			return ret;
 		}
+
+		/// <summary>
+		/// This is an alternative to the built-in SKBitmap.FromImage.
+		/// The problem with SKBitmap.FromImage is that it ignores the color type of the input image, and
+		/// uses SKImageInfo.PlatformColorType.
+		/// The code is the same as SKBitmap.FromImage except for respecting color type.
+		/// See https://github.com/mono/SkiaSharp/blob/7d7766532a4666f56944e65bee1c2158c320f09c/binding/Binding/SKBitmap.cs#L830-L843
+		/// </summary>
+		public static SKBitmap ToSKBitmap(this SKImage image)
+		{
+			if (image == null)
+			{
+				throw new ArgumentNullException(nameof(image));
+			}
+
+			var info = new SKImageInfo(image.Width, image.Height, image.ColorType, image.AlphaType);
+			var bmp = new SKBitmap(info);
+			if (!image.ReadPixels(info, bmp.GetPixels(), info.RowBytes, 0, 0))
+			{
+				bmp.Dispose();
+				bmp = null;
+			}
+
+			return bmp!;
+		}
 	}
 }

src/Uno.UI.RuntimeTests/Tests/Windows_UI_Xaml_Media_Imaging/Given_RenderTargetBitmap.cs

@@ -88,10 +88,6 @@ namespace Uno.UI.RuntimeTests.Tests.Windows_UI_Xaml_Media_Imaging
 		[Ignore("Not implemented yet.")]
 #elif __MACOS__
 		[Ignore("Currently fails on macOS, part of #9282 epic")]
-#elif __SKIA__
-		[Ignore("Currently fails on CI for skia GTK (works locally)")]
-#elif __ANDROID__
-		[Ignore("Currently fails on CI for Android https://github.com/unoplatform/uno/issues/9080")]
 #endif
 		public async Task When_Render_Then_CanRenderOnCanvas()
 		{

src/Uno.UI/UI/Xaml/Media/Imaging/RenderTargetBitmap.Android.cs

@@ -9,6 +9,7 @@ using Windows.Foundation;
 using Java.Nio;
 using Android.Views;
 using Uno.UI.Xaml.Media;
+using System.Runtime.InteropServices;
 
 namespace Windows.UI.Xaml.Media.Imaging
 {
@@ -39,9 +40,27 @@ namespace Windows.UI.Xaml.Media.Imaging
 		/// <inheritdoc />
 		private protected override bool IsSourceReady => _buffer != null;
 
+		[StructLayout(LayoutKind.Explicit)]
+		private struct ByteArrayToIntArrayBridge
+		{
+			[FieldOffset(0)]
+			public byte[] ByteArray;
+
+			[FieldOffset(0)]
+			public int[] IntArray;
+
+#pragma warning disable CS8618 // Non-nullable field must contain a non-null value when exiting constructor. Consider declaring as nullable.
+			public ByteArrayToIntArrayBridge(byte[] bytes)
+#pragma warning restore CS8618 // Non-nullable field must contain a non-null value when exiting constructor. Consider declaring as nullable.
+			{
+				ByteArray = bytes;
+			}
+		}
+
 		private static ImageData Open(byte[] buffer, int bufferLength, int width, int height)
 		{
-			return ImageData.FromBitmap(BitmapFactory.DecodeByteArray(buffer, 0, bufferLength));
+			var bitmap = Bitmap.CreateBitmap(new ByteArrayToIntArrayBridge(buffer).IntArray, width, height, Bitmap.Config.Argb8888!);
+			return ImageData.FromBitmap(bitmap);
 		}
 
 		private (int ByteCount, int Width, int Height) RenderAsBgra8_Premul(UIElement element, ref byte[]? buffer, Size? scaledSize = null)
@@ -105,5 +124,20 @@ namespace Windows.UI.Xaml.Media.Imaging
 				SetSoftwareRendering(element, false);
 			}
 		}
+
+		[global::System.Runtime.CompilerServices.MethodImpl(global::System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]
+		private static void SwapRB(ref byte[] buffer, int byteCount)
+		{
+			for (var i = 0; i < byteCount; i += 4)
+			{
+				//Swap R and B chanal
+				Swap(ref buffer![i], ref buffer![i + 2]);
+			}
+		}
+
+		private static void Swap(ref byte a, ref byte b)
+		{
+			(a, b) = (b, a);
+		}
 	}
 }

src/Uno.UI/UI/Xaml/Media/Imaging/RenderTargetBitmap.cs

@@ -172,23 +172,6 @@ namespace Windows.UI.Xaml.Media.Imaging
 				buffer = ArrayPool<byte>.Shared.Rent(length);
 			}
 		}
-
-#if !__IOS__ && !__MACOS__
-		[global::System.Runtime.CompilerServices.MethodImpl(global::System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]
-		private static void SwapRB(ref byte[] buffer, int byteCount)
-		{
-			for (var i = 0; i < byteCount; i += 4)
-			{
-				//Swap R and B chanal
-				Swap(ref buffer![i], ref buffer![i + 2]);
-			}
-		}
-
-		private static void Swap(ref byte a, ref byte b)
-		{
-			(a, b) = (b, a);
-		}
-#endif
 #endif
 		#endregion
 	}

src/Uno.UI/UI/Xaml/Media/Imaging/RenderTargetBitmap.skia.cs

@@ -14,21 +14,8 @@ namespace Windows.UI.Xaml.Media.Imaging
 		private const int _bitsPerComponent = 8;
 		private const int _bytesPerPixel = _bitsPerPixel / _bitsPerComponent;
 
-		delegate void SwapColor(ref byte[] buffer, int byteCount);
-
-		private static readonly SwapColor? _platformSwap = RuntimeInformation.IsOSPlatform(OSPlatform.OSX) ? SwapRB : default;
-
 		private static ImageData Open(byte[] buffer, int bufferLength, int width, int height)
 		{
-			if (_platformSwap is not null)
-			{
-				var swappedBuffer = default(byte[]);
-				EnsureBuffer(ref swappedBuffer, bufferLength);
-				Array.Copy(buffer, swappedBuffer!, bufferLength);
-				_platformSwap(ref swappedBuffer!, bufferLength);
-				buffer = swappedBuffer;
-			}
-
 			var bufferHandle = GCHandle.Alloc(buffer, GCHandleType.Pinned);
 			try
 			{
@@ -70,7 +57,7 @@ namespace Windows.UI.Xaml.Media.Imaging
 
 			var img = surface.Snapshot();
 
-			var bitmap = SKBitmap.FromImage(img);
+			var bitmap = img.ToSKBitmap();
 			if (scaledSize.HasValue)
 			{
 				var scaledBitmap = bitmap.Resize(
@@ -84,8 +71,6 @@ namespace Windows.UI.Xaml.Media.Imaging
 			var byteCount = bitmap.ByteCount;
 			EnsureBuffer(ref buffer, byteCount);
 			bitmap.GetPixelSpan().CopyTo(buffer);
-			//On macOS color as stored as rgba
-			_platformSwap?.Invoke(ref buffer!, byteCount);
 			bitmap?.Dispose();
 			return (byteCount, width, height);
 		}