chore: Extract to convertMTLTextureToSkImage

ios/Skia Render Layer/SkImageHelpers.h

@@ -11,6 +11,8 @@
 
 #import <Foundation/Foundation.h>
 #import <AVFoundation/AVFoundation.h>
+#import <MetalKit/MetalKit.h>
+
 #import <include/gpu/GrRecordingContext.h>
 
 #import "SkImage.h"
@@ -26,6 +28,10 @@ public:
    Convert a CMSampleBuffer to an SkImage. Format has to be RGB.
    */
   static sk_sp<SkImage> convertCMSampleBufferToSkImage(GrRecordingContext* context, CMSampleBufferRef sampleBuffer);
+  /**
+   Convert a MTLTexture to an SkImage. Format has to be RGB.
+   */
+  static sk_sp<SkImage> convertMTLTextureToSkImage(GrRecordingContext* context, id<MTLTexture> mtlTexture);
   /**
    Creates a Center Crop Transformation Rect so that the source rect fills (aspectRatio: cover) the destination rect.
    The return value should be passed as a sourceRect to a canvas->draw...Rect(..) function, destinationRect should stay the same.

ios/Skia Render Layer/SkImageHelpers.mm

@@ -86,6 +86,20 @@ sk_sp<SkImage> SkImageHelpers::convertCMSampleBufferToSkImage(GrRecordingContext
   return image;
 }
 
+sk_sp<SkImage> SkImageHelpers::convertMTLTextureToSkImage(GrRecordingContext* context, id<MTLTexture> texture) {
+  // Convert the rendered MTLTexture to an SkImage
+  GrMtlTextureInfo textureInfo;
+  textureInfo.fTexture.retain((__bridge void*)texture);
+  GrBackendTexture backendTexture(texture.width, texture.height, GrMipmapped::kNo, textureInfo);
+  auto image = SkImages::AdoptTextureFrom(context,
+                                          backendTexture,
+                                          kTopLeft_GrSurfaceOrigin,
+                                          kBGRA_8888_SkColorType,
+                                          kOpaque_SkAlphaType,
+                                          SkColorSpace::MakeSRGB());
+  return image;
+}
+
 SkRect SkImageHelpers::createCenterCropRect(SkRect sourceRect, SkRect destinationRect) {
   SkSize src;
   if (destinationRect.width() / destinationRect.height() > sourceRect.width() / sourceRect.height()) {

ios/Skia Render Layer/SkiaMetalCanvasProvider.mm

@@ -23,7 +23,7 @@ SkiaMetalCanvasProvider::SkiaMetalCanvasProvider(): std::enable_shared_from_this
   _layerContext.layer.pixelFormat = MTLPixelFormatBGRA8Unorm;
   // Set up DisplayLink
   _layerContext.displayLink = [[VisionDisplayLink alloc] init];
-  
+
   _isValid = true;
 }
 
@@ -65,16 +65,16 @@ void SkiaMetalCanvasProvider::render() {
   if (_width == -1 && _height == -1) {
     return;
   }
-  
+
   if (!_hasNewFrame) {
     // No new Frame has arrived in the meantime.
     // We don't need to re-draw the texture to the screen if nothing has changed, abort.
     return;
   }
-  
+
   @autoreleasepool {
     auto context = _layerContext.skiaContext.get();
-    
+
     // Create a Skia Surface from the CAMetalLayer (use to draw to the View)
     GrMTLHandle drawableHandle;
     auto surface = SkSurface::MakeFromCAMetalLayer(context,
@@ -88,17 +88,17 @@ void SkiaMetalCanvasProvider::render() {
     if (surface == nullptr || surface->getCanvas() == nullptr) {
       throw std::runtime_error("Skia surface could not be created from parameters.");
     }
-    
+
     auto canvas = surface->getCanvas();
-    
+
     // Lock the Mutex so we can operate on the Texture atomically without
     // renderFrameToCanvas() overwriting in between from a different thread
     std::unique_lock lock(_textureMutex);
-  
+
     // Get the texture
     auto texture = _offscreenContext.texture;
     if (texture == nil) return;
-    
+
     // Calculate Center Crop (aspectRatio: cover) transform
     auto sourceRect = SkRect::MakeXYWH(0, 0, texture.width, texture.height);
     auto destinationRect = SkRect::MakeXYWH(0, 0, surface->width(), surface->height());
@@ -109,40 +109,32 @@ void SkiaMetalCanvasProvider::render() {
     // The Canvas is equal to the View size, where-as the Frame has a different size (e.g. 4k)
     // We scale the Canvas to the exact dimensions of the Frame so that the user can use the Frame as a coordinate system
     canvas->save();
-    
+
     auto scaleW = static_cast<double>(surface->width()) / texture.width;
     auto scaleH = static_cast<double>(surface->height()) / texture.height;
     auto scale = MAX(scaleW, scaleH);
     canvas->scale(scale, scale);
     canvas->translate(offsetX, offsetY);
-    
+
     // Convert the rendered MTLTexture to an SkImage
-    GrMtlTextureInfo textureInfo;
+    auto image = SkImageHelpers::convertMTLTextureToSkImage(context, texture);
-    textureInfo.fTexture.retain((__bridge void*)texture);
+
-    GrBackendTexture backendTexture(texture.width, texture.height, GrMipmapped::kNo, textureInfo);
-    auto image = SkImage::MakeFromTexture(context,
-                                          backendTexture,
-                                          kTopLeft_GrSurfaceOrigin,
-                                          kBGRA_8888_SkColorType,
-                                          kOpaque_SkAlphaType,
-                                          SkColorSpace::MakeSRGB());
-    
     // Draw the Texture (Frame) to the Canvas
     canvas->drawImage(image, 0, 0);
-    
+
     // Restore the scale & transform
     canvas->restore();
-    
+
     surface->flushAndSubmit();
-    
+
     // Pass the drawable into the Metal Command Buffer and submit it to the GPU
     id<CAMetalDrawable> drawable = (__bridge id<CAMetalDrawable>)drawableHandle;
     id<MTLCommandBuffer> commandBuffer([_layerContext.commandQueue commandBuffer]);
     [commandBuffer presentDrawable:drawable];
     [commandBuffer commit];
-    
+
     _hasNewFrame = false;
-    
+
     lock.unlock();
   }
 }
@@ -170,14 +162,14 @@ void SkiaMetalCanvasProvider::renderFrameToCanvas(CMSampleBufferRef sampleBuffer
     if (pixelBuffer == nil) {
       throw std::runtime_error("drawFrame: Pixel Buffer is corrupt/empty.");
     }
-    
+
     // Lock Mutex to block the runLoop from overwriting the _currentDrawable
     std::unique_lock lock(_textureMutex);
-    
+
     // Get the Metal Texture we use for in-memory drawing
     auto texture = getTexture(CVPixelBufferGetWidth(pixelBuffer),
                               CVPixelBufferGetHeight(pixelBuffer));
-    
+
     // Get & Lock the writeable Texture from the Metal Drawable
     GrMtlTextureInfo fbInfo;
     fbInfo.fTexture.retain((__bridge void*)texture);
@@ -185,9 +177,9 @@ void SkiaMetalCanvasProvider::renderFrameToCanvas(CMSampleBufferRef sampleBuffer
                                     texture.height,
                                     1,
                                     fbInfo);
-    
+
     auto context = _offscreenContext.skiaContext.get();
-    
+
     // Create a Skia Surface from the writable Texture
     auto surface = SkSurface::MakeFromBackendRenderTarget(context,
                                                           backendRT,
@@ -195,35 +187,35 @@ void SkiaMetalCanvasProvider::renderFrameToCanvas(CMSampleBufferRef sampleBuffer
                                                           kBGRA_8888_SkColorType,
                                                           nullptr,
                                                           nullptr);
-    
+
     if (surface == nullptr || surface->getCanvas() == nullptr) {
       throw std::runtime_error("Skia surface could not be created from parameters.");
     }
-    
+
     // Lock the Frame's PixelBuffer for the duration of the Frame Processor so the user can safely do operations on it
     CVPixelBufferLockBaseAddress(pixelBuffer, kCVPixelBufferLock_ReadOnly);
-    
+
     // Converts the CMSampleBuffer to an SkImage - RGB.
     auto image = SkImageHelpers::convertCMSampleBufferToSkImage(context, sampleBuffer);
-    
+
     auto canvas = surface->getCanvas();
-    
+
     // Clear everything so we keep it at a clean state
     canvas->clear(SkColors::kBlack);
-    
+
     // Draw the Image into the Frame (aspectRatio: cover)
     // The Frame Processor might draw the Frame again (through render()) to pass a custom paint/shader,
     // but that'll just overwrite the existing one - no need to worry.
     canvas->drawImage(image, 0, 0);
-    
+
     // Call the JS Frame Processor.
     drawCallback(canvas);
-    
+
     // Flush all appended operations on the canvas and commit it to the SkSurface
     surface->flushAndSubmit();
-    
+
     _hasNewFrame = true;
-    
+
     lock.unlock();
     CVPixelBufferUnlockBaseAddress(pixelBuffer, kCVPixelBufferLock_ReadOnly);
   }