Use explicit native mappings instead of casts

Author: JimBobSquarePants

src/ImageSharp.Drawing.WebGPU/WebGPUDrawingBackend.CompositePixels.cs

@@ -62,7 +62,7 @@ internal static bool TryGetCompositeTextureFormat<TPixel>(out WebGPUTextureForma
             return false;
         }
 
-        formatId = WebGPUTextureFormatMapper.FromSilk(r.TextureFormat);
+        formatId = WebGPUTextureFormatMapper.FromNative(r.TextureFormat);
         requiredFeature = r.RequiredFeature;
         return true;
     }
@@ -79,7 +79,7 @@ internal static void GetCompositeTextureFormatInfo(
         out TextureFormat textureFormat,
         out FeatureName requiredFeature)
     {
-        textureFormat = WebGPUTextureFormatMapper.ToSilk(format);
+        textureFormat = WebGPUTextureFormatMapper.ToNative(format);
         requiredFeature = Find(textureFormat).RequiredFeature;
     }
 

src/ImageSharp.Drawing.WebGPU/WebGPUDrawingBackend.cs

@@ -121,7 +121,7 @@ public void RenderScene<TPixel>(
         // so staging does not repeat the generic frame capability checks.
         _ = nativeTarget.TryGetNativeSurface(out NativeSurface? nativeSurface);
         WebGPUNativeTarget webGPUTarget = nativeSurface!.GetNativeTarget<WebGPUNativeTarget>();
-        TextureFormat textureFormat = WebGPUTextureFormatMapper.ToSilk(webGPUTarget.TargetFormat);
+        TextureFormat textureFormat = WebGPUTextureFormatMapper.ToNative(webGPUTarget.TargetFormat);
 
         if (webGPUTarget.TargetFormat != formatId)
         {

src/ImageSharp.Drawing.WebGPU/WebGPUFlushContext.cs

@@ -175,7 +175,7 @@ public static WebGPUFlushContext Create<TPixel>(
         _ = frame.TryGetNativeSurface(out NativeSurface? nativeSurface);
         WebGPUNativeTarget nativeTarget = nativeSurface!.GetNativeTarget<WebGPUNativeTarget>();
         WebGPU api = WebGPURuntime.GetApi();
-        TextureFormat textureFormat = WebGPUTextureFormatMapper.ToSilk(nativeTarget.TargetFormat);
+        TextureFormat textureFormat = WebGPUTextureFormatMapper.ToNative(nativeTarget.TargetFormat);
         Rectangle bounds = frame.Bounds;
         Rectangle nativeBounds = new(0, 0, nativeTarget.Width, nativeTarget.Height);
         WebGPURuntime.DeviceSharedState deviceState = WebGPURuntime.GetOrCreateDeviceState(api, nativeTarget.DeviceHandle);

src/ImageSharp.Drawing.WebGPU/WebGPUSurfaceResources.cs

@@ -236,8 +236,8 @@ private void ConfigureSurfaceCore(WebGPUPresentMode presentMode, Size framebuffe
         SurfaceConfiguration surfaceConfiguration = new()
         {
             Usage = TextureUsage.RenderAttachment | TextureUsage.CopySrc | TextureUsage.CopyDst | TextureUsage.TextureBinding,
-            Format = WebGPUTextureFormatMapper.ToSilk(this.Format),
-            PresentMode = (SilkPresentMode)(int)presentMode,
+            Format = WebGPUTextureFormatMapper.ToNative(this.Format),
+            PresentMode = ToNative(presentMode),
             Width = (uint)framebufferSize.Width,
             Height = (uint)framebufferSize.Height,
         };
@@ -248,6 +248,15 @@ private void ConfigureSurfaceCore(WebGPUPresentMode presentMode, Size framebuffe
         this.Api.SurfaceConfigure((Surface*)surfaceReference.Handle, ref surfaceConfiguration);
     }
 
+    private static SilkPresentMode ToNative(WebGPUPresentMode presentMode)
+        => presentMode switch
+        {
+            WebGPUPresentMode.Fifo => SilkPresentMode.Fifo,
+            WebGPUPresentMode.Immediate => SilkPresentMode.Immediate,
+            WebGPUPresentMode.Mailbox => SilkPresentMode.Mailbox,
+            _ => throw new InvalidOperationException("The WebGPU present mode mapping is incomplete.")
+        };
+
     /// <summary>
     /// Acquires the next presentable frame from <see cref="SurfaceHandle"/> and wraps it as a
     /// <see cref="WebGPUSurfaceFrame"/> with a ready-to-use <see cref="DrawingCanvas"/>.

src/ImageSharp.Drawing.WebGPU/WebGPUTextureFormat.cs

@@ -10,7 +10,6 @@ namespace SixLabors.ImageSharp.Drawing.Processing.Backends;
 /// </summary>
 /// <remarks>
 /// Only formats with storage texture binding support are included.
-/// Numeric values match the WebGPU texture-format constants.
 /// </remarks>
 public enum WebGPUTextureFormat
 {

src/ImageSharp.Drawing.WebGPU/WebGPUTextureFormatMapper.cs

@@ -15,14 +15,28 @@ internal static class WebGPUTextureFormatMapper
     /// </summary>
     /// <param name="formatId">The public texture format identifier.</param>
     /// <returns>The matching <see cref="TextureFormat"/> value.</returns>
-    public static TextureFormat ToSilk(WebGPUTextureFormat formatId)
-        => (TextureFormat)(int)formatId;
+    public static TextureFormat ToNative(WebGPUTextureFormat formatId)
+        => formatId switch
+        {
+            WebGPUTextureFormat.Rgba8Unorm => TextureFormat.Rgba8Unorm,
+            WebGPUTextureFormat.Rgba8Snorm => TextureFormat.Rgba8Snorm,
+            WebGPUTextureFormat.Bgra8Unorm => TextureFormat.Bgra8Unorm,
+            WebGPUTextureFormat.Rgba16Float => TextureFormat.Rgba16float,
+            _ => throw new InvalidOperationException("The WebGPU texture format mapping is incomplete.")
+        };
 
     /// <summary>
     /// Converts a native texture format to the corresponding public WebGPU texture format identifier.
     /// </summary>
     /// <param name="textureFormat">The native texture format.</param>
     /// <returns>The matching <see cref="WebGPUTextureFormat"/> value.</returns>
-    public static WebGPUTextureFormat FromSilk(TextureFormat textureFormat)
-        => (WebGPUTextureFormat)(int)textureFormat;
+    public static WebGPUTextureFormat FromNative(TextureFormat textureFormat)
+        => textureFormat switch
+        {
+            TextureFormat.Rgba8Unorm => WebGPUTextureFormat.Rgba8Unorm,
+            TextureFormat.Rgba8Snorm => WebGPUTextureFormat.Rgba8Snorm,
+            TextureFormat.Bgra8Unorm => WebGPUTextureFormat.Bgra8Unorm,
+            TextureFormat.Rgba16float => WebGPUTextureFormat.Rgba16Float,
+            _ => throw new InvalidOperationException("The native texture format mapping is incomplete.")
+        };
 }

src/ImageSharp.Drawing.WebGPU/WebGPUWindow.cs

@@ -533,11 +533,41 @@ private static WindowOptions CreateSilkOptions(WebGPUWindowOptions options)
 
     private static Point ToPoint(Vector2D<int> value) => new(value.X, value.Y);
 
-    private static NativeWindowState ToNative(WebGPUWindowState state) => (NativeWindowState)(int)state;
-
-    private static WebGPUWindowState FromNative(NativeWindowState state) => (WebGPUWindowState)(int)state;
-
-    private static NativeWindowBorder ToNative(WebGPUWindowBorder border) => (NativeWindowBorder)(int)border;
-
-    private static WebGPUWindowBorder FromNative(NativeWindowBorder border) => (WebGPUWindowBorder)(int)border;
+    private static NativeWindowState ToNative(WebGPUWindowState state)
+        => state switch
+        {
+            WebGPUWindowState.Normal => NativeWindowState.Normal,
+            WebGPUWindowState.Minimized => NativeWindowState.Minimized,
+            WebGPUWindowState.Maximized => NativeWindowState.Maximized,
+            WebGPUWindowState.Fullscreen => NativeWindowState.Fullscreen,
+            _ => throw new InvalidOperationException("The WebGPU window state mapping is incomplete.")
+        };
+
+    private static WebGPUWindowState FromNative(NativeWindowState state)
+        => state switch
+        {
+            NativeWindowState.Normal => WebGPUWindowState.Normal,
+            NativeWindowState.Minimized => WebGPUWindowState.Minimized,
+            NativeWindowState.Maximized => WebGPUWindowState.Maximized,
+            NativeWindowState.Fullscreen => WebGPUWindowState.Fullscreen,
+            _ => throw new InvalidOperationException("The native window state mapping is incomplete.")
+        };
+
+    private static NativeWindowBorder ToNative(WebGPUWindowBorder border)
+        => border switch
+        {
+            WebGPUWindowBorder.Resizable => NativeWindowBorder.Resizable,
+            WebGPUWindowBorder.Fixed => NativeWindowBorder.Fixed,
+            WebGPUWindowBorder.Hidden => NativeWindowBorder.Hidden,
+            _ => throw new InvalidOperationException("The WebGPU window border mapping is incomplete.")
+        };
+
+    private static WebGPUWindowBorder FromNative(NativeWindowBorder border)
+        => border switch
+        {
+            NativeWindowBorder.Resizable => WebGPUWindowBorder.Resizable,
+            NativeWindowBorder.Fixed => WebGPUWindowBorder.Fixed,
+            NativeWindowBorder.Hidden => WebGPUWindowBorder.Hidden,
+            _ => throw new InvalidOperationException("The native window border mapping is incomplete.")
+        };
 }

tests/ImageSharp.Drawing.Tests/Processing/Backends/WebGPUTextureFormatMapperTests.cs

@@ -9,7 +9,7 @@ namespace SixLabors.ImageSharp.Drawing.Tests.Processing.Backends;
 public class WebGPUTextureFormatMapperTests
 {
     [Fact]
-    public void Mapper_UsesExactSilkEnumValues_ForAllSupportedFormats()
+    public void Mapper_UsesExplicitMappings_ForAllSupportedFormats()
     {
         (WebGPUTextureFormat Drawing, TextureFormat Silk)[] mappings =
         [
@@ -23,9 +23,8 @@ public void Mapper_UsesExactSilkEnumValues_ForAllSupportedFormats()
 
         foreach ((WebGPUTextureFormat drawing, TextureFormat silk) in mappings)
         {
-            Assert.Equal((int)silk, (int)drawing);
-            Assert.Equal(silk, WebGPUTextureFormatMapper.ToSilk(drawing));
-            Assert.Equal(drawing, WebGPUTextureFormatMapper.FromSilk(silk));
+            Assert.Equal(silk, WebGPUTextureFormatMapper.ToNative(drawing));
+            Assert.Equal(drawing, WebGPUTextureFormatMapper.FromNative(silk));
         }
     }
 }