feat(composition): Implement DistantDiffuseEffect + Sample

src/SamplesApp/UITests.Shared/Windows_UI_Composition/EffectBrushTests.xaml

@@ -31,5 +31,6 @@
 		<Grid x:Name="sepiaGrid" Width="200" Height="200" VerticalAlignment="Top" HorizontalAlignment="Left" ToolTipService.ToolTip="SepiaEffect"/>
 		<Grid x:Name="tempTintGrid" Width="200" Height="200" VerticalAlignment="Top" HorizontalAlignment="Left" ToolTipService.ToolTip="TemperatureAndTintEffect"/>
 		<Grid x:Name="matrixGrid" Width="200" Height="200" VerticalAlignment="Top" HorizontalAlignment="Left" ToolTipService.ToolTip="ColorMatrixEffect"/>
+		<Grid x:Name="ddGrid" Width="200" Height="200" VerticalAlignment="Top" HorizontalAlignment="Left" ToolTipService.ToolTip="DistantDiffuseEffect"/>
 	</GridView>
 </UserControl>

src/SamplesApp/UITests.Shared/Windows_UI_Composition/EffectBrushTests.xaml.cs

@@ -41,7 +41,7 @@ public EffectBrushTests()
 		private void EffectBrushTests_Loaded(object sender, RoutedEventArgs e)
 		{
 #if !WINDOWS_UWP
-			var compositor = Window.Current.Compositor;
+			var compositor = Windows.UI.Xaml.Window.Current.Compositor;
 
 			var effect = new SimpleBlurEffect() { Source = new CompositionEffectSourceParameter("sourceBrush"), BlurAmount = 5.0f };
 			var factory = compositor.CreateEffectFactory(effect);
@@ -199,6 +199,23 @@ private void EffectBrushTests_Loaded(object sender, RoutedEventArgs e)
 			var effectBrush21 = factory21.CreateBrush();
 
 			matrixGrid.Background = new EffectTesterBrush(effectBrush21);
+
+			var surface3 = LoadedImageSurface.StartLoadFromUri(new Uri("https://user-images.githubusercontent.com/34550324/268126129-1bb2c5e7-24a4-41dc-bcdf-59f533c0d173.png"));
+			surface3.LoadCompleted += (s, o) =>
+			{
+				if (o.Status == LoadedImageSourceLoadStatus.Success)
+				{
+					var brush = compositor.CreateSurfaceBrush(surface3);
+
+					var effect22 = new SimpleDistantDiffuseEffect() { Source = new SimpleLuminanceToAlphaEffect() { Source = new CompositionEffectSourceParameter("sourceBrush") }, DiffuseAmount = 5.0f, Azimuth = (float)MathEx.ToRadians(180.0f) };
+					var factory22 = compositor.CreateEffectFactory(effect22);
+					var effectBrush22 = factory22.CreateBrush();
+
+					effectBrush22.SetSourceParameter("sourceBrush", brush);
+
+					ddGrid.Background = new XamlCompositionBrush(effectBrush22);
+				}
+			};
 #endif
 		}
 
@@ -215,7 +232,7 @@ public EffectTesterBrush(CompositionEffectBrush effectBrush, int imgSize = 200)
 
 			protected override void OnConnected()
 			{
-				var compositor = Window.Current.Compositor;
+				var compositor = Windows.UI.Xaml.Window.Current.Compositor;
 				var surface = LoadedImageSurface.StartLoadFromUri(new Uri($"https://avatars.githubusercontent.com/u/52228309?s={_imgSize}&v=4"));
 				surface.LoadCompleted += (s, o) =>
 				{
@@ -243,7 +260,7 @@ public EffectTesterBrushWithSecondaryBrush(CompositionEffectBrush effectBrush, C
 
 			protected override void OnConnected()
 			{
-				var compositor = Window.Current.Compositor;
+				var compositor = Windows.UI.Xaml.Window.Current.Compositor;
 				var surface = LoadedImageSurface.StartLoadFromUri(new Uri("https://avatars.githubusercontent.com/u/52228309?s=200&v=4"));
 				surface.LoadCompleted += (s, o) =>
 				{
@@ -259,6 +276,18 @@ protected override void OnConnected()
 			}
 		}
 
+		private class XamlCompositionBrush : XamlCompositionBrushBase
+		{
+			CompositionBrush _brush;
+
+			public XamlCompositionBrush(CompositionBrush brush) => _brush = brush;
+
+			protected override void OnConnected()
+			{
+				CompositionBrush = _brush;
+			}
+		}
+
 #if !WINDOWS_UWP
 		[Guid("1FEB6D69-2FE6-4AC9-8C58-1D7F93E7A6A5")]
 		private class SimpleBlurEffect : IGraphicsEffect, IGraphicsEffectSource, IGraphicsEffectD2D1Interop
@@ -1613,6 +1642,89 @@ public object GetProperty(uint index)
 			public IGraphicsEffectSource GetSource(uint index) => Source;
 			public uint GetSourceCount() => 1;
 		}
+
+		[Guid("3E7EFD62-A32D-46D4-A83C-5278889AC954")]
+		private class SimpleDistantDiffuseEffect : IGraphicsEffect, IGraphicsEffectSource, IGraphicsEffectD2D1Interop
+		{
+			private string _name = "SimpleDistantDiffuseEffect";
+			private Guid _id = new Guid("3E7EFD62-A32D-46D4-A83C-5278889AC954");
+
+			public string Name
+			{
+				get => _name;
+				set => _name = value;
+			}
+
+			public float Azimuth { get; set; } = 0.0f;
+
+			public float Elevation { get; set; } = 0.0f;
+
+			public float DiffuseAmount { get; set; } = 1.0f;
+
+			public Color LightColor { get; set; } = Colors.White;
+
+			public IGraphicsEffectSource Source { get; set; }
+
+			public Guid GetEffectId() => _id;
+
+			public void GetNamedPropertyMapping(string name, out uint index, out GraphicsEffectPropertyMapping mapping)
+			{
+				switch (name)
+				{
+					case "Azimuth":
+						{
+							index = 0;
+							mapping = GraphicsEffectPropertyMapping.RadiansToDegrees;
+							break;
+						}
+					case "Elevation":
+						{
+							index = 1;
+							mapping = GraphicsEffectPropertyMapping.RadiansToDegrees;
+							break;
+						}
+					case "DiffuseAmount":
+						{
+							index = 2;
+							mapping = GraphicsEffectPropertyMapping.Direct;
+							break;
+						}
+					case "LightColor":
+						{
+							index = 3;
+							mapping = GraphicsEffectPropertyMapping.Direct;
+							break;
+						}
+					default:
+						{
+							index = 0xFF;
+							mapping = (GraphicsEffectPropertyMapping)0xFF;
+							break;
+						}
+				}
+			}
+
+			public object GetProperty(uint index)
+			{
+				switch (index)
+				{
+					case 0:
+						return Azimuth;
+					case 1:
+						return Elevation;
+					case 2:
+						return DiffuseAmount;
+					case 3:
+						return LightColor;
+					default:
+						return null;
+				}
+			}
+
+			public uint GetPropertyCount() => 4;
+			public IGraphicsEffectSource GetSource(uint index) => Source;
+			public uint GetSourceCount() => 1;
+		}
 #endif
 	}
 }

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

@@ -1145,6 +1145,37 @@ half4 main()
 											sourceFilter, new(bounds));
 									}
 
+									return null;
+								}
+							case EffectType.DistantDiffuseEffect:
+								{
+									if (effectInterop.GetSourceCount() == 1 && effectInterop.GetPropertyCount() == 4 && effectInterop.GetSource(0) is IGraphicsEffectSource source)
+									{
+										SKImageFilter sourceFilter = GenerateEffectFilter(source, bounds);
+										if (sourceFilter is null)
+											return null;
+
+										effectInterop.GetNamedPropertyMapping("Azimuth", out uint azimuthProp, out GraphicsEffectPropertyMapping azimuthMapping);
+										effectInterop.GetNamedPropertyMapping("Elevation", out uint elevationProp, out GraphicsEffectPropertyMapping elevationMapping);
+										effectInterop.GetNamedPropertyMapping("DiffuseAmount", out uint amountProp, out _);
+										effectInterop.GetNamedPropertyMapping("LightColor", out uint colorProp, out _);
+
+										float azimuth = (float)effectInterop.GetProperty(azimuthProp);
+										float elevation = (float)effectInterop.GetProperty(elevationProp);
+										float amount = (float)effectInterop.GetProperty(amountProp);
+										Color color = (Color)effectInterop.GetProperty(colorProp);
+
+										if (azimuthMapping == GraphicsEffectPropertyMapping.RadiansToDegrees)
+											azimuth *= 180.0f / MathF.PI;
+
+										if (elevationMapping == GraphicsEffectPropertyMapping.RadiansToDegrees)
+											elevation *= 180.0f / MathF.PI;
+
+										Vector3 lightVector = EffectHelpers.GetLightVector(azimuth, elevation);
+
+										return SKImageFilter.CreateDistantLitDiffuse(new SKPoint3(lightVector.X, lightVector.Y, lightVector.Z), color.ToSKColor(), 1.0f, amount, sourceFilter, new(bounds));
+									}
+
 									return null;
 								}
 							case EffectType.Unsupported:

src/Uno.UWP/Graphics/Effects/Interop/EffectHelpers.cs

@@ -2,6 +2,7 @@
 using Windows.Foundation;
 using Windows.Graphics.Effects;
 using System.Runtime.InteropServices;
+using System.Numerics;
 
 namespace Windows.Graphics.Effects.Interop
 {
@@ -111,5 +112,56 @@ public static EffectType GetEffectType(Guid effectId)
 			else
 				return EffectType.Unsupported;
 		}
+
+		internal static Vector3 GetLightVector(float azimuthInDegrees, float elevationInDegrees)
+		{
+			// MathEx.ToRadians isn't used here to precisely match the original function
+			float azimuthInRadians = azimuthInDegrees * 0.0174532925199433f;
+			float elevationInRadians = 0.0174532925199433f * elevationInDegrees;
+			float cosElevation = MathF.Cos(elevationInRadians);
+
+			Vector3 lightVector = new();
+			lightVector.X = cosElevation * MathF.Cos(azimuthInRadians);
+			lightVector.Y = cosElevation * MathF.Sin(azimuthInRadians);
+			lightVector.Z = MathF.Sin(elevationInRadians);
+
+			Normalize3DVector(ref lightVector);
+			return lightVector;
+		}
+
+		private static void Normalize3DVector(ref Vector3 vector)
+		{
+			float fa = 0.0f;
+			float flSqSum = 0.0f;
+			float flSqSuma = 0.0f;
+			Vector3 rgflSq = vector * vector;
+
+			flSqSum = rgflSq[0] + rgflSq[1] + rgflSq[2];
+			if (flSqSum <= 0.0000099999997f)
+			{
+				vector.X = 0.0f;
+				vector.Y = 0.0f;
+				vector.Z = 0.0f;
+			}
+			else
+			{
+				for (int i = 0; i < 3; ++i)
+				{
+					if (rgflSq[i] == 0)
+					{
+						vector[i] = 0.0f;
+					}
+					else
+					{
+						flSqSuma += rgflSq[i];
+					}
+				}
+
+				fa = MathF.Sqrt(flSqSuma);
+				vector.X = vector.X / fa;
+				vector.Y = vector.Y / fa;
+				vector.Z = vector.Z / fa;
+			}
+		}
 	}
 }

src/Uno.UWP/Graphics/Effects/Interop/EffectHelpers.skia.cs

@@ -108,9 +108,11 @@ public static SKBlendMode ToSkia(this D2D1CompositeMode compositeMode)
 				case D2D1CompositeMode.Add:
 					return SKBlendMode.Plus;
 
+				case D2D1CompositeMode.Copy:
+					return SKBlendMode.Src;
+
 				// Unsupported modes
 
-				case D2D1CompositeMode.Copy:
 				case D2D1CompositeMode.MaskInvert:
 				default:
 					return (SKBlendMode)0xFF;
@@ -123,10 +125,13 @@ public static SKShaderTileMode ToSkia(this D2D1BorderEdgeMode mode)
 			{
 				case D2D1BorderEdgeMode.Clamp:
 					return SKShaderTileMode.Clamp;
+
 				case D2D1BorderEdgeMode.Wrap:
 					return SKShaderTileMode.Repeat;
+
 				case D2D1BorderEdgeMode.Mirror:
 					return SKShaderTileMode.Mirror;
+
 				default:
 					return SKShaderTileMode.Clamp;
 			}