ObjC: Split out NV12 texture uploading into separate class

webrtc/sdk/objc/Framework/Classes/RTCNV12TextureCache.m

+/*
+ *  Copyright 2017 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#import "RTCNV12TextureCache.h"
+
+#import "RTCShader+Private.h"
+
+@implementation RTCNV12TextureCache {
+  CVOpenGLESTextureCacheRef _textureCache;
+  CVOpenGLESTextureRef _yTexture;
+  CVOpenGLESTextureRef _uvTexture;
+}
+
+- (GLuint)yTexture {
+  return CVOpenGLESTextureGetName(_yTexture);
+}
+
+- (GLuint)uvTexture {
+  return CVOpenGLESTextureGetName(_uvTexture);
+}
+
+- (instancetype)initWithContext:(EAGLContext *)context {
+  if (self = [super init]) {
+    CVReturn ret = CVOpenGLESTextureCacheCreate(
+        kCFAllocatorDefault, NULL,
+#if COREVIDEO_USE_EAGLCONTEXT_CLASS_IN_API
+        context,
+#else
+        (__bridge void *)context,
+#endif
+        NULL, &_textureCache);
+    if (ret != kCVReturnSuccess) {
+      self = nil;
+    }
+  }
+  return self;
+}
+
+- (BOOL)uploadFrameToTextures:(RTCVideoFrame *)frame {
+  CVPixelBufferRef pixelBuffer = frame.nativeHandle;
+  NSParameterAssert(pixelBuffer);
+
+  // Y-plane.
+  const int lumaWidth = CVPixelBufferGetWidthOfPlane(pixelBuffer, 0);

[sakal, 2017/04/26 09:11:58]

nit: Can you make 0 and 1 here constants.

[magjed_webrtc, 2017/04/26 13:14:41]

Done (it's a named argument to a function now).

+  const int lumaHeight = CVPixelBufferGetHeightOfPlane(pixelBuffer, 0);
+
+  _yTexture = nil;
+  CVReturn ret = CVOpenGLESTextureCacheCreateTextureFromImage(
+      kCFAllocatorDefault, _textureCache, pixelBuffer, NULL, GL_TEXTURE_2D,
+      RTC_PIXEL_FORMAT, lumaWidth, lumaHeight, RTC_PIXEL_FORMAT,
+      GL_UNSIGNED_BYTE, 0, &_yTexture);
+  if (ret != kCVReturnSuccess) {
+    CFRelease(_yTexture);
+    return NO;
+  }
+  NSAssert(CVOpenGLESTextureGetTarget(_yTexture) == GL_TEXTURE_2D,
+           @"Unexpected GLES texture target");
+  glBindTexture(GL_TEXTURE_2D, self.yTexture);
+  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+
+  // UV-plane.
+  const int chromaWidth = CVPixelBufferGetWidthOfPlane(pixelBuffer, 1);
+  const int chromeHeight = CVPixelBufferGetHeightOfPlane(pixelBuffer, 1);
+
+  _uvTexture = nil;
+  ret = CVOpenGLESTextureCacheCreateTextureFromImage(
+      kCFAllocatorDefault, _textureCache, pixelBuffer, NULL, GL_TEXTURE_2D,
+      GL_LUMINANCE_ALPHA, chromaWidth, chromeHeight, GL_LUMINANCE_ALPHA,
+      GL_UNSIGNED_BYTE, 1, &_uvTexture);
+  if (ret != kCVReturnSuccess) {
+    CFRelease(_uvTexture);
+    CFRelease(_yTexture);
+    return NO;
+  }
+  NSAssert(CVOpenGLESTextureGetTarget(_uvTexture) == GL_TEXTURE_2D,
+           @"Unexpected GLES texture target");
+  glBindTexture(GL_TEXTURE_2D, self.uvTexture);
+  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+
+  return YES;
+}
+
+- (void)releaseTextures {
+  if (_uvTexture) {
+    CFRelease(_uvTexture);
+    _uvTexture = nil;
+  }
+  if (_yTexture) {
+    CFRelease(_yTexture);
+    _yTexture = nil;
+  }
+}
+
+- (void)dealloc {
+  [self releaseTextures];
+  if (_textureCache) {
+    CFRelease(_textureCache);
+    _textureCache = nil;
+  }
+}
+
+@end
+