mus: Use BufferQueue and GLHelper from display_compositor.

components/mus/surfaces/buffer_queue.h

-// Copyright 2016 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 COMPONENTS_MUS_SURFACES_BUFFER_QUEUE_H_
-#define COMPONENTS_MUS_SURFACES_BUFFER_QUEUE_H_
-
-#include <stddef.h>
-
-#include <deque>
-#include <memory>
-#include <vector>
-
-#include "base/macros.h"
-#include "base/memory/ref_counted.h"
-#include "gpu/command_buffer/client/gles2_interface.h"
-#include "ui/gfx/geometry/rect.h"
-#include "ui/gfx/geometry/size.h"
-#include "ui/gfx/native_widget_types.h"
-
-namespace cc {
-class ContextProvider;
-}
-
-namespace gfx {
-class GpuMemoryBuffer;
-}
-
-class SkRegion;
-
-namespace mus {
-
-class MojoGpuMemoryBufferManager;
-class GLHelper;
-
-// Provides a surface that manages its own buffers, backed by GpuMemoryBuffers
-// created using CHROMIUM_gpu_memory_buffer_image. Double/triple buffering is
-// implemented internally. Doublebuffering occurs if PageFlipComplete is called
-// before the next BindFramebuffer call, otherwise it creates extra buffers.
-class BufferQueue {
- public:
-  BufferQueue(scoped_refptr<cc::ContextProvider> context_provider,
-              uint32_t texture_target,
-              uint32_t internalformat,
-              gfx::AcceleratedWidget widget);
-  virtual ~BufferQueue();
-
-  void Initialize();
-
-  void BindFramebuffer();
-  void SwapBuffers(const gfx::Rect& damage);
-  void PageFlipComplete();
-  void Reshape(const gfx::Size& size, float scale_factor);
-
-  void RecreateBuffers();
-
-  unsigned int current_texture_id() const {
-    return current_surface_ ? current_surface_->texture : 0;
-  }
-  unsigned int fbo() const { return fbo_; }
-
- private:
-  friend class AllocatedSurface;
-
-  struct AllocatedSurface {
-    AllocatedSurface(BufferQueue* buffer_queue,
-                     std::unique_ptr<gfx::GpuMemoryBuffer> buffer,
-                     unsigned int texture,
-                     unsigned int image,
-                     const gfx::Rect& rect);
-    ~AllocatedSurface();
-    BufferQueue* const buffer_queue;
-    std::unique_ptr<gfx::GpuMemoryBuffer> buffer;
-    const unsigned int texture;
-    const unsigned int image;
-    gfx::Rect damage;  // This is the damage for this frame from the previous.
-  };
-
-  void FreeAllSurfaces();
-
-  void FreeSurfaceResources(AllocatedSurface* surface);
-
-  // Copy everything that is in |copy_rect|, except for what is in
-  // |exclude_rect| from |source_texture| to |texture|.
-  virtual void CopyBufferDamage(int texture,
-                                int source_texture,
-                                const gfx::Rect& new_damage,
-                                const gfx::Rect& old_damage);
-
-  void UpdateBufferDamage(const gfx::Rect& damage);
-
-  void CopySubBufferDamage(GLenum target,
-                           GLuint texture,
-                           GLuint previous_texture,
-                           const SkRegion& new_damage,
-                           const SkRegion& old_damage);
-
-  // Return a surface, available to be drawn into.
-  std::unique_ptr<AllocatedSurface> GetNextSurface();
-
-  std::unique_ptr<AllocatedSurface> RecreateBuffer(
-      std::unique_ptr<AllocatedSurface> surface);
-
-  gfx::Size size_;
-  scoped_refptr<cc::ContextProvider> context_provider_;
-
-  unsigned int fbo_;
-  size_t allocated_count_;
-  unsigned int texture_target_;
-  unsigned int internal_format_;
-  // This surface is currently bound. This may be nullptr if no surface has
-  // been bound, or if allocation failed at bind.
-  std::unique_ptr<AllocatedSurface> current_surface_;
-  // The surface currently on the screen, if any.
-  std::unique_ptr<AllocatedSurface> displayed_surface_;
-  // These are free for use, and are not nullptr.
-  std::vector<std::unique_ptr<AllocatedSurface>> available_surfaces_;
-  // These have been swapped but are not displayed yet. Entries of this deque
-  // may be nullptr, if they represent frames that have been destroyed.
-  std::deque<std::unique_ptr<AllocatedSurface>> in_flight_surfaces_;
-  gfx::AcceleratedWidget widget_;
-
-  DISALLOW_COPY_AND_ASSIGN(BufferQueue);
-};
-
-}  // namespace mus
-
-#endif  // COMPONENTS_MUS_SURFACES_BUFFER_QUEUE_H_