Drop frontbuffers with ui-use-gpu-process, synchronized with browser, decoupled from backbuffer dro…

content/common/gpu/texture_image_transport_surface.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_TEXTURE_IMAGE_TRANSPORT_SURFACE_H_
 #define CONTENT_COMMON_GPU_TEXTURE_IMAGE_TRANSPORT_SURFACE_H_
 #pragma once
 
 #include "base/basictypes.h"
 #include "content/common/gpu/gpu_command_buffer_stub.h"
@@ skipping 17 matching lines @@
   virtual void Destroy() OVERRIDE;
   virtual bool Resize(const gfx::Size& size) OVERRIDE;
   virtual bool IsOffscreen() OVERRIDE;
   virtual bool SwapBuffers() OVERRIDE;
   virtual gfx::Size GetSize() OVERRIDE;
   virtual void* GetHandle() OVERRIDE;
   virtual std::string GetExtensions() OVERRIDE;
   virtual unsigned int GetBackingFrameBufferObject() OVERRIDE;
   virtual bool PostSubBuffer(int x, int y, int width, int height) OVERRIDE;
   virtual bool OnMakeCurrent(gfx::GLContext* context) OVERRIDE;
-  virtual void SetBufferAllocation(BufferAllocationState state) OVERRIDE;
+  virtual void SetBackbufferAllocation(bool allocated) OVERRIDE;
+  virtual void SetFrontbufferAllocation(bool allocated) OVERRIDE;
   virtual void* GetShareHandle() OVERRIDE;
   virtual void* GetDisplay() OVERRIDE;
   virtual void* GetConfig() OVERRIDE;
 
  protected:
   // ImageTransportSurface implementation.
   virtual void OnNewSurfaceACK(
       uint64 surface_handle, TransportDIB::Handle shm_handle) OVERRIDE;
   virtual void OnBuffersSwappedACK() OVERRIDE;
   virtual void OnPostSubBufferACK() OVERRIDE;
   virtual void OnResizeViewACK() OVERRIDE;
+  virtual void OnDiscardSurface(uint64 surface_id) OVERRIDE;
   virtual void OnResize(gfx::Size size) OVERRIDE;
 
   // GpuCommandBufferStub::DestructionObserver implementation.
   virtual void OnWillDestroyStub(GpuCommandBufferStub* stub) OVERRIDE;
 
  private:
   // A texture backing the front/back buffer in the parent stub.
   struct Texture {
     Texture();
     ~Texture();
 
     // The client-side id in the parent stub.
     uint32 client_id;
 
     // The currently allocated size.
     gfx::Size size;
 
     // Whether or not that texture has been sent to the client yet.
     bool sent_to_client;
+    bool allocated;
+    bool suggested_allocation;

[piman, 2012/05/04 00:03:49]

I don't think suggested_allocation belongs here. Or it doesn't mean what I think
it means

When we call SetBackbufferAllocation(false) we mean, we don't need a back
buffer. It doesn't matter whichever texture that is currently, but if they
change (e.g. because of a swap), it doesn't make sense to move the suggested
allocation from back to front.

It'd be better I think to have a suggested_back_allocation_ and a
suggested_front_allocation_ at the top level.

[mmocny, 2012/05/04 18:55:52]

Suggested allocation has evolved with this patch and has become a misnomer, so I
will rename it.

It now means "did send suggest discard frontbuffer message, and that request is
still valid".

I've moved this out into top level and overall cleaned things up significantly.

On 2012/05/04 00:03:49, piman wrote:

 
     // The texture info in the parent stub.
     gpu::gles2::TextureManager::TextureInfo::Ref info;
   };
 
   virtual ~TextureImageTransportSurface();
-  void CreateBackTexture(const gfx::Size& size);
-  void ReleaseBackTexture();
-  void AttachBackTextureToFBO();
+  void CreateTexture(int id, const gfx::Size& size);
+  void RequestReleaseTexture(int id);
+  void ReleaseTexture(int id);
+  void AttachTextureToFBO(int id);
   void ReleaseParentStub();
+  int front() const { return front_; }
   int back() const { return 1 - front_; }
 
   // The framebuffer that represents this surface (service id). Allocated lazily
   // in OnMakeCurrent.
   uint32 fbo_id_;
 
   // The front and back buffers.
   Texture textures_[2];
 
   gfx::Rect previous_damage_rect_;
 
   // Indicates which of the 2 above is the front buffer.
   int front_;
 
   // Whether or not the command buffer stub has been destroyed.
   bool stub_destroyed_;
 
   scoped_ptr<ImageTransportHelper> helper_;
   GpuCommandBufferStub* parent_stub_;
 
   DISALLOW_COPY_AND_ASSIGN(TextureImageTransportSurface);
 };
 
 #endif  // CONTENT_COMMON_GPU_TEXTURE_IMAGE_TRANSPORT_SURFACE_H_