Addition of GL_CHROMIUM_copy_texture extension.

gpu/command_buffer/service/gles2_cmd_copy_texture_chromium.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_GLES2_CMD_COPY_TEXTURE_CHROMIUM_H_
+#define GPU_COMMAND_BUFFER_SERVICE_GLES2_CMD_COPY_TEXTURE_CHROMIUM_H_
+
+#include "gpu/command_buffer/service/gl_utils.h"
+
+// This class encapsulates the resources required to implement the
+// GL_CHROMIUM_copy_texture extension.  The copy operation is performed
+// via a blit to a framebuffer object.
+class CopyTextureCHROMIUMResourceManager {
+ public:
+  CopyTextureCHROMIUMResourceManager() : initialized_(false) {}
+
+  void Initialize();
+  void Destroy();
+
+  void DoCopyTexture(GLenum target, GLuint source_id, GLuint dest_id,
+                     GLint level, bool flip_y, bool premultiply_alpha);
+
+  // The attributes used during invocation of the extension.
+  static const GLuint kVertexPositionAttrib = 0;
+  static const GLuint kVertexTextureAttrib = 1;
+
+ private:
+  bool initialized_;
+
+  static const int kNumPrograms = 4;
+  GLuint programs_[kNumPrograms];
+  GLuint buffer_ids_[2];
+  GLuint framebuffer_;
+  GLuint sampler_locations_[kNumPrograms];
+
+  DISALLOW_COPY_AND_ASSIGN(CopyTextureCHROMIUMResourceManager);
+};
+
+#endif  // GPU_COMMAND_BUFFER_SERVICE_GLES2_CMD_COPY_TEXTURE_CHROMIUM_H_
+
+