Add external surface rendering mode

cc/gl_renderer.cc

 // Copyright 2010 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/gl_renderer.h"
 
 #include "base/debug/trace_event.h"
 #include "base/logging.h"
 #include "base/string_split.h"
 #include "base/string_util.h"
@@ skipping 918 matching lines @@
 
 void GLRenderer::drawStreamVideoQuad(const DrawingFrame& frame, const StreamVideoDrawQuad* quad)
 {
     static float glMatrix[16];
 
     DCHECK(m_capabilities.usingEglImage);
 
     const VideoStreamTextureProgram* program = videoStreamTextureProgram();
     setUseProgram(program->program());
 
-    toGLMatrix(&glMatrix[0], quad->matrix);
-    GLC(context(), context()->uniformMatrix4fv(program->vertexShader().texMatrixLocation(), 1, false, glMatrix));
+    if (quad->texture_id == 0) {
+        // When texture_id == 0, punch a hole instead of rendering.
+        GLC(m_context, m_context->blendFunc(GL_ZERO, GL_ONE_MINUS_SRC_ALPHA));
+        drawQuadGeometry(frame, quad->quadTransform(), quad->rect, program->vertexShader().matrixLocation());
+        GLC(m_context, m_context->blendFunc(GL_ONE, GL_ONE_MINUS_SRC_ALPHA));
+    } else {

[danakj, 2012/12/13 05:35:42]

if you return at the end of the if() then you don't need the else{}.

[wonsik2, 2012/12/17 04:36:05]

Done.

+        toGLMatrix(&glMatrix[0], quad->matrix);
+        GLC(context(), context()->uniformMatrix4fv(program->vertexShader().texMatrixLocation(), 1, false, glMatrix));
 
-    GLC(context(), context()->bindTexture(GL_TEXTURE_EXTERNAL_OES, quad->texture_id));
+        GLC(context(), context()->bindTexture(GL_TEXTURE_EXTERNAL_OES, quad->texture_id));
 
-    GLC(context(), context()->uniform1i(program->fragmentShader().samplerLocation(), 0));
+        GLC(context(), context()->uniform1i(program->fragmentShader().samplerLocation(), 0));
 
-    setShaderOpacity(quad->opacity(), program->fragmentShader().alphaLocation());
-    drawQuadGeometry(frame, quad->quadTransform(), quad->rect, program->vertexShader().matrixLocation());
+        setShaderOpacity(quad->opacity(), program->fragmentShader().alphaLocation());
+        drawQuadGeometry(frame, quad->quadTransform(), quad->rect, program->vertexShader().matrixLocation());
+    }
 }
 
 struct TextureProgramBinding {
     template<class Program> void set(
         Program* program, WebKit::WebGraphicsContext3D* context)
     {
         DCHECK(program && (program->initialized() || context->isContextLost()));
         programId = program->program();
         samplerLocation = program->fragmentShader().samplerLocation();
         matrixLocation = program->vertexShader().matrixLocation();
@@ skipping 788 matching lines @@
 
     releaseRenderPassTextures();
 }
 
 bool GLRenderer::isContextLost()
 {
     return (m_context->getGraphicsResetStatusARB() != GL_NO_ERROR);
 }
 
 }  // namespace cc