Update GL_IMPLEMENTATION_COLOR_READ_FORMAT for BGRA

gpu/command_buffer/service/gles2_cmd_decoder.cc

 // Copyright (c) 2012 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 "gpu/command_buffer/service/gles2_cmd_decoder.h"
 
 #include <limits.h>
 #include <stddef.h>
 #include <stdint.h>
 #include <stdio.h>
@@ skipping 5088 matching lines @@
   }
 }
 
 bool GLES2DecoderImpl::GetHelper(
     GLenum pname, GLint* params, GLsizei* num_written) {
   DCHECK(num_written);
   if (gfx::GetGLImplementation() != gfx::kGLImplementationEGLGLES2) {
     switch (pname) {
       case GL_IMPLEMENTATION_COLOR_READ_FORMAT:
         *num_written = 1;
-        // Return the GL implementation's preferred format and (see below type)
-        // if we have the GL extension that exposes this. This allows the GPU
-        // client to use the implementation's preferred format for glReadPixels
-        // for optimisation.
+        // Return an additional (other than GL_RGBA) read format which the GL
+        // implementation supports. If no additional format is available, this
+        // function will return GL_RGBA.
         //
-        // A conflicting extension (GL_ARB_ES2_compatibility) specifies an error
-        // case when requested on integer/floating point buffers but which is
-        // acceptable on GLES2 and with the GL_OES_read_format extension.
+        // If the GL_OES_read_format extension is available, we query GL
+        // directly. Otherwise we use our internal implementation.
+        //
+        // A conflicting extension (GL_ARB_ES2_compatibility) specifies an
+        // error case when requested on integer/floating point buffers but
+        // which is acceptable on GLES2 and with the GL_OES_read_format
+        // extension.
         //
         // Therefore if an error occurs we swallow the error and use the
         // internal implementation.
         if (params) {
           if (context_->HasExtension("GL_OES_read_format")) {
             ScopedGLErrorSuppressor suppressor("GLES2DecoderImpl::GetHelper",
                                                GetErrorState());
             glGetIntegerv(pname, params);
             if (glGetError() == GL_NO_ERROR)
               return true;
           }
-          *params = GLES2Util::GetGLReadPixelsImplementationFormat(
-              GetBoundReadFrameBufferInternalFormat());
+          *params = GLES2Util::GetGLReadPixelsAdditionalFormat(
+              GetBoundReadFrameBufferInternalFormat(),
+              GetBoundReadFrameBufferTextureType());
         }
         return true;
       case GL_IMPLEMENTATION_COLOR_READ_TYPE:
         *num_written = 1;
         if (params) {
           if (context_->HasExtension("GL_OES_read_format")) {
             ScopedGLErrorSuppressor suppressor("GLES2DecoderImpl::GetHelper",
                                                GetErrorState());
             glGetIntegerv(pname, params);
             if (glGetError() == GL_NO_ERROR)
               return true;
           }
-          *params = GLES2Util::GetGLReadPixelsImplementationType(
+          *params = GLES2Util::GetGLReadPixelsTypeForAdditionalFormat(
               GetBoundReadFrameBufferInternalFormat(),
               GetBoundReadFrameBufferTextureType());
         }
         return true;
       case GL_MAX_FRAGMENT_UNIFORM_VECTORS:
         *num_written = 1;
         if (params) {
           *params = group_->max_fragment_uniform_vectors();
         }
         return true;
@@ skipping 10793 matching lines @@
 }
 
 // Include the auto-generated part of this file. We split this because it means
 // we can easily edit the non-auto generated parts right here in this file
 // instead of having to edit some template or the code generator.
 #include "base/macros.h"
 #include "gpu/command_buffer/service/gles2_cmd_decoder_autogen.h"
 
 }  // namespace gles2
 }  // namespace gpu