Partial swap implementation for surfaceless

content/browser/compositor/buffer_queue.h

 // Copyright 2014 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_BROWSER_COMPOSITOR_BUFFERED_OUTPUT_SURFACE_H_
 #define CONTENT_BROWSER_COMPOSITOR_BUFFERED_OUTPUT_SURFACE_H_
 
 #include <queue>
 #include <vector>
 
 #include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
 #include "content/common/content_export.h"
+#include "ui/gfx/rect.h"
 #include "ui/gfx/size.h"
 
 namespace cc {
 class ContextProvider;
 }
 
 namespace content {
 
 // Provides a surface that manages its own uffers, backed by
 // CreateImageCHROMIUM. Double/triple buffering is implemented
 // internally. Doublebuffering occurs if PageFlipComplete is called before
 // the next BindFramebuffer call, otherwise it creates extra buffers.
 class CONTENT_EXPORT BufferQueue {
  public:
   BufferQueue(scoped_refptr<cc::ContextProvider> context_provider,
               unsigned int internalformat);
-  ~BufferQueue();
+  virtual ~BufferQueue();
 
   bool Initialize();
 
   void BindFramebuffer();
-  void SwapBuffers();
+  void SwapBuffers(const gfx::Rect& damage);
   void PageFlipComplete();
   void Reshape(const gfx::Size& size, float scale_factor);
 
   unsigned int current_texture_id() { return current_surface_.texture; }
 
  private:
   friend class BufferQueueTest;
+
   struct AllocatedSurface {
     AllocatedSurface() : texture(0), image(0) {}
-    AllocatedSurface(unsigned int texture, unsigned int image)
-        : texture(texture), image(image) {}
+    AllocatedSurface(unsigned int texture,
+                     unsigned int image,
+                     const gfx::Rect& rect)
+        : texture(texture), image(image), damage(rect) {}
     unsigned int texture;
     unsigned int image;
+    gfx::Rect damage;  // This is the damage for this frame from the previous.
   };
 
   void FreeAllSurfaces();
 
   void FreeSurface(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);
+
   // Return a surface, available to be drawn into.
   AllocatedSurface GetNextSurface();
 
   gfx::Size size_;
   scoped_refptr<cc::ContextProvider> context_provider_;
   unsigned int fbo_;
   size_t allocated_count_;
   unsigned int internalformat_;
   AllocatedSurface current_surface_;  // This surface is currently bound.
   std::vector<AllocatedSurface> available_surfaces_;  // These are free for use.
-  std::queue<AllocatedSurface> in_flight_surfaces_;
+  std::deque<AllocatedSurface> in_flight_surfaces_;
 
   DISALLOW_COPY_AND_ASSIGN(BufferQueue);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_COMPOSITOR_BUFFERED_OUTPUT_SURFACE_H_