FlutterExternalTexture Class Reference

#include <FlutterExternalTexture.h>

Inheritance diagram for FlutterExternalTexture:

Instance Methods
(nonnull instancetype)	- initWithFlutterTexture:darwinMetalContext:
(int64_t)	- textureID
(BOOL)	- populateTexture:
(instancetype)	- initWithFlutterTexture:darwinMetalContext: [implementation]
(BOOL)	- populateTexture: [implementation]
(BOOL)	- populateTextureFromYUVAPixelBuffer:textureOut: [implementation]
(BOOL)	- populateTextureFromRGBAPixelBuffer:textureOut: [implementation]

Detailed Description

Embedding side texture wrappers for Metal external textures. Used to bridge FlutterTexture object and handle the texture copy request the Flutter engine.

Definition at line 18 of file FlutterExternalTexture.h.

Method Documentation

initWithFlutterTexture:darwinMetalContext: [1/2]

- (instancetype) initWithFlutterTexture: (id<FlutterTexture>)  texture darwinMetalContext: (FlutterDarwinContextMetalSkia*)  context

implementation

Definition at line 16 of file FlutterExternalTexture.mm.

                                      :(id<FlutterTexture>)texture
                    darwinMetalContext:(FlutterDarwinContextMetalSkia*)context {
  self = [super init];
  if (self) {
    _texture = texture;
    _textureID = reinterpret_cast<int64_t>(_texture);
    _darwinMetalContext = context;
  }
  return self;
}

initWithFlutterTexture:darwinMetalContext: [2/2]

- (nonnull instancetype) initWithFlutterTexture:		(nonnull id< FlutterTexture >)	texture
darwinMetalContext:		(nonnull FlutterDarwinContextMetalSkia *)	context

Initializes a texture adapter with |texture|.

populateTexture: [1/2]

- (BOOL) populateTexture: (FlutterMetalExternalTexture*)  textureOut

implementation

Definition at line 16 of file FlutterExternalTexture.mm.

                       :(FlutterMetalExternalTexture*)textureOut {
  // Copy the pixel buffer from the FlutterTexture instance implemented on the user side.
  fml::CFRef<CVPixelBufferRef> pixelBuffer([_texture copyPixelBuffer]);
 
  if (!pixelBuffer) {
    return NO;
  }
 
  OSType pixel_format = CVPixelBufferGetPixelFormatType(pixelBuffer);
  if (pixel_format == kCVPixelFormatType_420YpCbCr8BiPlanarVideoRange ||
      pixel_format == kCVPixelFormatType_420YpCbCr8BiPlanarFullRange) {
    return [self populateTextureFromYUVAPixelBuffer:pixelBuffer textureOut:textureOut];
  } else if (pixel_format == kCVPixelFormatType_32BGRA) {
    return [self populateTextureFromRGBAPixelBuffer:pixelBuffer textureOut:textureOut];
  } else {
    NSLog(@"Unsupported pixel format: %d", pixel_format);
    return NO;
  }
}

populateTexture: [2/2]

- (BOOL) populateTexture:

(nonnull FlutterMetalExternalTexture *)

metalTexture

Accepts texture buffer copy request from the Flutter engine. When the user side marks the textureID as available, the Flutter engine will callback to this method and ask for populate the |metalTexture| object, such as the texture type and the format of the pixel buffer and the texture object.

populateTextureFromRGBAPixelBuffer:textureOut:

- (BOOL) populateTextureFromRGBAPixelBuffer: (nonnull CVPixelBufferRef)  pixelBuffer textureOut: (nonnull FlutterMetalExternalTexture*)  textureOut

implementation

Definition at line 16 of file FlutterExternalTexture.mm.

                                          :(nonnull CVPixelBufferRef)pixelBuffer
                                textureOut:(nonnull FlutterMetalExternalTexture*)textureOut {
  SkISize textureSize =
      SkISize::Make(CVPixelBufferGetWidth(pixelBuffer), CVPixelBufferGetHeight(pixelBuffer));
 
  CVMetalTextureRef cvMetalTexture = nullptr;
  CVReturn cvReturn =
      CVMetalTextureCacheCreateTextureFromImage(/*allocator=*/kCFAllocatorDefault,
                                                /*textureCache=*/_darwinMetalContext.textureCache,
                                                /*sourceImage=*/pixelBuffer,
                                                /*textureAttributes=*/nullptr,
                                                /*pixelFormat=*/MTLPixelFormatBGRA8Unorm,
                                                /*width=*/textureSize.width(),
                                                /*height=*/textureSize.height(),
                                                /*planeIndex=*/0u,
                                                /*texture=*/&cvMetalTexture);
 
  if (cvReturn != kCVReturnSuccess) {
    NSLog(@"Could not create Metal texture from pixel buffer: CVReturn %d", cvReturn);
    return NO;
  }
 
  _textures = {(__bridge FlutterMetalTextureHandle)CVMetalTextureGetTexture(cvMetalTexture)};
  CVBufferRelease(cvMetalTexture);
 
  textureOut->num_textures = 1;
  textureOut->height = textureSize.height();
  textureOut->width = textureSize.width();
  textureOut->pixel_format = FlutterMetalExternalTexturePixelFormat::kRGBA;
  textureOut->textures = _textures.data();
 
  return YES;
}

populateTextureFromYUVAPixelBuffer:textureOut:

- (BOOL) populateTextureFromYUVAPixelBuffer: (nonnull CVPixelBufferRef)  pixelBuffer textureOut: (nonnull FlutterMetalExternalTexture*)  textureOut

implementation

Definition at line 16 of file FlutterExternalTexture.mm.

                                          :(nonnull CVPixelBufferRef)pixelBuffer
                                textureOut:(nonnull FlutterMetalExternalTexture*)textureOut {
  CVMetalTextureRef yCVMetalTexture = nullptr;
  CVMetalTextureRef uvCVMetalTextureRef = nullptr;
  SkISize textureSize =
      SkISize::Make(CVPixelBufferGetWidth(pixelBuffer), CVPixelBufferGetHeight(pixelBuffer));
 
  CVReturn yCVReturn = CVMetalTextureCacheCreateTextureFromImage(
      /*allocator=*/kCFAllocatorDefault,
      /*textureCache=*/_darwinMetalContext.textureCache,
      /*sourceImage=*/pixelBuffer,
      /*textureAttributes=*/nullptr,
      /*pixelFormat=*/MTLPixelFormatR8Unorm,
      /*width=*/CVPixelBufferGetWidthOfPlane(pixelBuffer, 0u),
      /*height=*/CVPixelBufferGetHeightOfPlane(pixelBuffer, 0u),
      /*planeIndex=*/0u,
      /*texture=*/&yCVMetalTexture);
 
  if (yCVReturn != kCVReturnSuccess) {
    NSLog(@"Could not create Metal texture from pixel buffer: CVReturn %d", yCVReturn);
    return NO;
  }
 
  CVReturn uvCVReturn = CVMetalTextureCacheCreateTextureFromImage(
      /*allocator=*/kCFAllocatorDefault,
      /*textureCache=*/_darwinMetalContext.textureCache,
      /*sourceImage=*/pixelBuffer,
      /*textureAttributes=*/nullptr,
      /*pixelFormat=*/MTLPixelFormatRG8Unorm,
      /*width=*/CVPixelBufferGetWidthOfPlane(pixelBuffer, 1u),
      /*height=*/CVPixelBufferGetHeightOfPlane(pixelBuffer, 1u),
      /*planeIndex=*/1u,
      /*texture=*/&uvCVMetalTextureRef);
 
  if (uvCVReturn != kCVReturnSuccess) {
    CVBufferRelease(yCVMetalTexture);
    NSLog(@"Could not create Metal texture from pixel buffer: CVReturn %d", uvCVReturn);
    return NO;
  }
 
  _textures = {(__bridge FlutterMetalTextureHandle)CVMetalTextureGetTexture(yCVMetalTexture),
               (__bridge FlutterMetalTextureHandle)CVMetalTextureGetTexture(uvCVMetalTextureRef)};
  CVBufferRelease(yCVMetalTexture);
  CVBufferRelease(uvCVMetalTextureRef);
 
  textureOut->num_textures = 2;
  textureOut->height = textureSize.height();
  textureOut->width = textureSize.width();
  textureOut->pixel_format = FlutterMetalExternalTexturePixelFormat::kYUVA;
  textureOut->textures = _textures.data();
  OSType pixel_format = CVPixelBufferGetPixelFormatType(pixelBuffer);
  textureOut->yuv_color_space = pixel_format == kCVPixelFormatType_420YpCbCr8BiPlanarVideoRange
                                    ? FlutterMetalExternalTextureYUVColorSpace::kBT601LimitedRange
                                    : FlutterMetalExternalTextureYUVColorSpace::kBT601FullRange;
 
  return YES;
}

textureID

- (int64_t) textureID

Returns the ID for the FlutterExternalTexture instance.

Definition at line 16 of file FlutterExternalTexture.mm.

                     {
  return _textureID;
}

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The documentation for this class was generated from the following files:

• shell/platform/darwin/macos/framework/Source/FlutterExternalTexture.h
• shell/platform/darwin/macos/framework/Source/FlutterExternalTexture.mm