Implement client side PBOs for glReadPixel

content/common/gpu/client/gl_helper.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 CONTENT_COMMON_GPU_CLIENT_GL_HELPER_H_
 #define CONTENT_COMMON_GPU_CLIENT_GL_HELPER_H_
 
 #include "base/atomicops.h"
 #include "base/basictypes.h"
 #include "base/callback.h"
 #include "base/memory/scoped_ptr.h"
 #include "third_party/WebKit/Source/Platform/chromium/public/WebGraphicsContext3D.h"
 
 namespace gfx {
 class Rect;
 class Size;
 }
 
 class SkRegion;
 
 namespace content {
 
 // Provides higher level operations on top of the WebKit::WebGraphicsContext3D
 // interfaces.
 class GLHelper {
  public:
-  GLHelper(WebKit::WebGraphicsContext3D* context,
-           WebKit::WebGraphicsContext3D* context_for_thread);
+  GLHelper(WebKit::WebGraphicsContext3D* context);
   virtual ~GLHelper();
 
   WebKit::WebGraphicsContext3D* context() const;
 
   // Copies the block of pixels specified with |src_subrect| from |src_texture|,
   // scales it to |dst_size|, and writes it into |out|.
   // |src_size| is the size of |src_texture|. The result is of format GL_BGRA
   // and is potentially flipped vertically to make it a correct image
   // representation.  |callback| is invoked with the copy result when the copy
   // operation has completed.
@@ skipping 36 matching lines @@
                            const SkRegion& new_damage,
                            const SkRegion& old_damage);
 
  private:
   class CopyTextureToImpl;
 
   // Creates |copy_texture_to_impl_| if NULL.
   void InitCopyTextToImpl();
 
   WebKit::WebGraphicsContext3D* context_;
-  WebKit::WebGraphicsContext3D* context_for_thread_;
   scoped_ptr<CopyTextureToImpl> copy_texture_to_impl_;
 
-  // The number of all GLHelper instances.
-  static base::subtle::Atomic32 count_;
-
   DISALLOW_COPY_AND_ASSIGN(GLHelper);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_COMMON_GPU_CLIENT_GL_HELPER_H_