Implement EXT_draw_buffers WebGL extention support in command buffer.

gpu/command_buffer/service/context_group.h

 // 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.
 
 #ifndef GPU_COMMAND_BUFFER_SERVICE_CONTEXT_GROUP_H_
 #define GPU_COMMAND_BUFFER_SERVICE_CONTEXT_GROUP_H_
 
 #include <string>
 #include <vector>
 #include "base/basictypes.h"
@@ skipping 85 matching lines @@
   }
 
   uint32 max_varying_vectors() const {
     return max_varying_vectors_;
   }
 
   uint32 max_vertex_uniform_vectors() const {
     return max_vertex_uniform_vectors_;
   }
 
+  uint32 max_color_attachments() const {
+    return max_color_attachments_;
+  }
+
+  uint32 max_draw_buffers() const {
+    return max_draw_buffers_;
+  }
+
   FeatureInfo* feature_info() {
     return feature_info_.get();
   }
 
   BufferManager* buffer_manager() const {
     return buffer_manager_.get();
   }
 
   FramebufferManager* framebuffer_manager() const {
     return framebuffer_manager_.get();
@@ skipping 27 matching lines @@
     return transfer_buffer_manager_.get();
   }
 
   IdAllocatorInterface* GetIdAllocator(unsigned namespace_id);
 
   uint32 GetMemRepresented() const;
 
   // Loses all the context associated with this group.
   void LoseContexts(GLenum reset_status);
 
+  // EXT_draw_buffer related states for backbuffer.
+  GLenum draw_buffer() const {
+    return draw_buffer_;
+  }
+  void set_draw_buffer(GLenum buf) {
+    draw_buffer_ = buf;
+  }
+
  private:
   friend class base::RefCounted<ContextGroup>;
   ~ContextGroup();
 
   bool CheckGLFeature(GLint min_required, GLint* v);
   bool CheckGLFeatureU(GLint min_required, uint32* v);
   bool QueryGLFeature(GLenum pname, GLint min_required, GLint* v);
   bool QueryGLFeatureU(GLenum pname, GLint min_required, uint32* v);
   bool HaveContexts();
 
   scoped_refptr<MailboxManager> mailbox_manager_;
   scoped_refptr<ImageManager> image_manager_;
   scoped_refptr<MemoryTracker> memory_tracker_;
   scoped_ptr<TransferBufferManagerInterface> transfer_buffer_manager_;
 
   bool enforce_gl_minimums_;
   bool bind_generates_resource_;
 
   uint32 max_vertex_attribs_;
   uint32 max_texture_units_;
   uint32 max_texture_image_units_;
   uint32 max_vertex_texture_image_units_;
   uint32 max_fragment_uniform_vectors_;
   uint32 max_varying_vectors_;
   uint32 max_vertex_uniform_vectors_;
+  uint32 max_color_attachments_;
+  uint32 max_draw_buffers_;
 
   ProgramCache* program_cache_;
 
   scoped_ptr<BufferManager> buffer_manager_;
 
   scoped_ptr<FramebufferManager> framebuffer_manager_;
 
   scoped_ptr<RenderbufferManager> renderbuffer_manager_;
 
   scoped_ptr<TextureManager> texture_manager_;
 
   scoped_ptr<ProgramManager> program_manager_;
 
   scoped_ptr<ShaderManager> shader_manager_;
 
   linked_ptr<IdAllocatorInterface>
       id_namespaces_[id_namespaces::kNumIdNamespaces];
 
   scoped_refptr<FeatureInfo> feature_info_;
 
   std::vector<base::WeakPtr<gles2::GLES2Decoder> > decoders_;
 
+  GLenum draw_buffer_;
+
   DISALLOW_COPY_AND_ASSIGN(ContextGroup);
 };
 
 }  // namespace gles2
 }  // namespace gpu
 
 #endif  // GPU_COMMAND_BUFFER_SERVICE_CONTEXT_GROUP_H_