Merge pull request #1 from frenzibyte/fix-metal-ios

Work around mono-level crash on iOS with interpreter

src/Veldrid.MetalBindings/MTLBlitCommandEncoder.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Runtime.InteropServices;
 using static Veldrid.MetalBindings.ObjectiveCRuntime;
 
 namespace Veldrid.MetalBindings
@@ -29,9 +30,9 @@ public void copyFromBuffer(
  UIntPtr destinationSlice,
  UIntPtr destinationLevel,
  MTLOrigin destinationOrigin)
- => objc_msgSend(
+ {
+ copyFromBuffer(
  NativePtr,
- sel_copyFromBuffer1,
  sourceBuffer.NativePtr,
  sourceOffset,
  sourceBytesPerRow,
@@ -40,7 +41,25 @@ public void copyFromBuffer(
  destinationTexture.NativePtr,
  destinationSlice,
  destinationLevel,
- destinationOrigin);
+ destinationOrigin.x,
+ destinationOrigin.y,
+ destinationOrigin.z);
+ }
+
+ [DllImport("@rpath/metal_mono_workaround.framework/metal_mono_workaround")]
+ private static extern void copyFromBuffer(
+ IntPtr encoder,
+ IntPtr sourceBuffer,
+ UIntPtr sourceOffset,
+ UIntPtr sourceBytesPerRow,
+ UIntPtr sourceBytesPerImage,
+ MTLSize sourceSize,
+ IntPtr destinationTexture,
+ UIntPtr destinationSlice,
+ UIntPtr destinationLevel,
+ UIntPtr destinationOriginX,
+ UIntPtr destinationOriginY,
+ UIntPtr destinationOriginZ);
 
  public void copyTextureToBuffer(
  MTLTexture sourceTexture,
@@ -106,4 +125,4 @@ public void copyFromTexture(
  private static readonly Selector sel_synchronizeResource = "synchronizeResource:";
  private static readonly Selector sel_endEncoding = "endEncoding";
  }
-}
+}

src/Veldrid.MetalBindings/metal-mono-workaround/README.md

@@ -0,0 +1,12 @@
+# Metal Mono Workaround
+
+On iOS, simply defining a P/Invoke method for `MTLBlitCommandEncoder.copyFromBuffer` and invoking it blows up the application. To work around that, we're defining a method that has a different signature that's friendly with Mono, which redirects back to the original method.
+
+This library should be referenced by any project that uses Veldrid. 
+
+To generate the library, build the Xcode project on both iPhone and iPhone Simulator architectures, and execute the following to generate the XCFramework:
+```bash
+xcodebuild -create-xcframework -framework ./Release-iphoneos/metal_mono_workaround.framework -framework ./Release-iphonesimulator/metal_mono_workaround.framework -output metal-mono-workaround.xcframework
+```
+
+Afterwards, reference the XCFramework in your project and it should work correctly.