Reland of Split iOS sdk in to separate targets

webrtc/sdk/objc/Framework/Classes/Video/RTCI420Shader.mm

Index: webrtc/sdk/objc/Framework/Classes/Video/RTCI420Shader.mm
diff --git a/webrtc/sdk/objc/Framework/Classes/Video/RTCI420Shader.mm b/webrtc/sdk/objc/Framework/Classes/Video/RTCI420Shader.mm
new file mode 100644
index 0000000000000000000000000000000000000000..83ecbe4d677009d0ee567562e6ee7fb9c0b1d804
--- /dev/null
+++ b/webrtc/sdk/objc/Framework/Classes/Video/RTCI420Shader.mm
@@ -0,0 +1,119 @@
+/*
+ *  Copyright 2016 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 "RTCShader.h"
+
+#import "RTCI420TextureCache.h"
+#import "RTCShader+Private.h"
+#import "WebRTC/RTCLogging.h"
+#import "WebRTC/RTCVideoFrame.h"
+
+#include "webrtc/base/optional.h"
+
+// Fragment shader converts YUV values from input textures into a final RGB
+// pixel. The conversion formula is from http://www.fourcc.org/fccyvrgb.php.
+static const char kI420FragmentShaderSource[] =
+  SHADER_VERSION
+  "precision highp float;"
+  FRAGMENT_SHADER_IN " vec2 v_texcoord;\n"
+  "uniform lowp sampler2D s_textureY;\n"
+  "uniform lowp sampler2D s_textureU;\n"
+  "uniform lowp sampler2D s_textureV;\n"
+  FRAGMENT_SHADER_OUT
+  "void main() {\n"
+  "    float y, u, v, r, g, b;\n"
+  "    y = " FRAGMENT_SHADER_TEXTURE "(s_textureY, v_texcoord).r;\n"
+  "    u = " FRAGMENT_SHADER_TEXTURE "(s_textureU, v_texcoord).r;\n"
+  "    v = " FRAGMENT_SHADER_TEXTURE "(s_textureV, v_texcoord).r;\n"
+  "    u = u - 0.5;\n"
+  "    v = v - 0.5;\n"
+  "    r = y + 1.403 * v;\n"
+  "    g = y - 0.344 * u - 0.714 * v;\n"
+  "    b = y + 1.770 * u;\n"
+  "    " FRAGMENT_SHADER_COLOR " = vec4(r, g, b, 1.0);\n"
+  "  }\n";
+
+@implementation RTCI420Shader {
+  RTCI420TextureCache* textureCache;
+  // Handles for OpenGL constructs.
+  GLuint _i420Program;
+  GLuint _vertexArray;
+  GLuint _vertexBuffer;
+  GLint _ySampler;
+  GLint _uSampler;
+  GLint _vSampler;
+  // Store current rotation and only upload new vertex data when rotation
+  // changes.
+  rtc::Optional<RTCVideoRotation> _currentRotation;
+}
+
+- (instancetype)initWithContext:(GlContextType *)context {
+  if (self = [super init]) {
+    textureCache = [[RTCI420TextureCache alloc] initWithContext:context];
+    glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
+    if (![self setupI420Program] ||
+        !RTCSetupVerticesForProgram(_i420Program, &_vertexBuffer, &_vertexArray)) {
+      RTCLog(@"Failed to initialize RTCI420Shader.");
+      self = nil;
+    }
+  }
+  return self;
+}
+
+- (void)dealloc {
+  glDeleteProgram(_i420Program);
+  glDeleteBuffers(1, &_vertexBuffer);
+  glDeleteVertexArrays(1, &_vertexArray);
+}
+
+- (BOOL)setupI420Program {
+  _i420Program = RTCCreateProgramFromFragmentSource(kI420FragmentShaderSource);
+  if (!_i420Program) {
+    return NO;
+  }
+  _ySampler = glGetUniformLocation(_i420Program, "s_textureY");
+  _uSampler = glGetUniformLocation(_i420Program, "s_textureU");
+  _vSampler = glGetUniformLocation(_i420Program, "s_textureV");
+
+  return (_ySampler >= 0 && _uSampler >= 0 && _vSampler >= 0);
+}
+
+- (BOOL)drawFrame:(RTCVideoFrame*)frame {
+  glUseProgram(_i420Program);
+
+  [textureCache uploadFrameToTextures:frame];
+
+#if !TARGET_OS_IPHONE
+  glBindVertexArray(_vertexArray);
+#endif
+
+  glActiveTexture(GL_TEXTURE0);
+  glBindTexture(GL_TEXTURE_2D, textureCache.yTexture);
+  glUniform1i(_ySampler, 0);
+
+  glActiveTexture(GL_TEXTURE1);
+  glBindTexture(GL_TEXTURE_2D, textureCache.uTexture);
+  glUniform1i(_uSampler, 1);
+
+  glActiveTexture(GL_TEXTURE2);
+  glBindTexture(GL_TEXTURE_2D, textureCache.vTexture);
+  glUniform1i(_vSampler, 2);
+
+  glBindBuffer(GL_ARRAY_BUFFER, _vertexBuffer);
+  if (!_currentRotation || frame.rotation != *_currentRotation) {
+    _currentRotation = rtc::Optional<RTCVideoRotation>(frame.rotation);
+    RTCSetVertexData(*_currentRotation);
+  }
+  glDrawArrays(GL_TRIANGLE_FAN, 0, 4);
+
+  return YES;
+}
+
+@end