Allow task pools to reason about transparency.

cc/raster/one_copy_tile_task_worker_pool.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 CC_RASTER_ONE_COPY_TILE_TASK_WORKER_POOL_H_
 #define CC_RASTER_ONE_COPY_TILE_TASK_WORKER_POOL_H_
 
 #include <set>
 
 #include "base/memory/weak_ptr.h"
@@ skipping 31 matching lines @@
  public:
   ~OneCopyTileTaskWorkerPool() override;
 
   static scoped_ptr<TileTaskWorkerPool> Create(
       base::SequencedTaskRunner* task_runner,
       TaskGraphRunner* task_graph_runner,
       ContextProvider* context_provider,
       ResourceProvider* resource_provider,
       int max_copy_texture_chromium_size,
       bool use_persistent_gpu_memory_buffers,
-      int max_staging_buffer_usage_in_bytes);
+      int max_staging_buffer_usage_in_bytes,
+      bool use_rgba_4444_texture_format);
 
   // Overridden from TileTaskWorkerPool:
   TileTaskRunner* AsTileTaskRunner() override;
 
   // Overridden from TileTaskRunner:
   void SetClient(TileTaskRunnerClient* client) override;
   void Shutdown() override;
   void ScheduleTasks(TileTaskQueue* queue) override;
   void CheckForCompletedTasks() override;
-  ResourceFormat GetResourceFormat() const override;
-  bool GetResourceRequiresSwizzle() const override;
+  ResourceFormat GetResourceFormat(bool must_support_alpha) const override;
+  bool GetResourceRequiresSwizzle(bool must_support_alpha) const override;
 
   // Overridden from TileTaskClient:
   scoped_ptr<RasterBuffer> AcquireBufferForRaster(
       const Resource* resource,
       uint64_t resource_content_id,
       uint64_t previous_content_id) override;
   void ReleaseBufferForRaster(scoped_ptr<RasterBuffer> buffer) override;
 
   // Overridden from base::trace_event::MemoryDumpProvider:
   bool OnMemoryDump(const base::trace_event::MemoryDumpArgs& args,
@@ skipping 10 matching lines @@
       bool include_images,
       uint64_t resource_content_id,
       uint64_t previous_content_id);
 
  protected:
   OneCopyTileTaskWorkerPool(base::SequencedTaskRunner* task_runner,
                             TaskGraphRunner* task_graph_runner,
                             ResourceProvider* resource_provider,
                             int max_copy_texture_chromium_size,
                             bool use_persistent_gpu_memory_buffers,
-                            int max_staging_buffer_usage_in_bytes);
+                            int max_staging_buffer_usage_in_bytes,
+                            bool use_rgba_4444_texture_format);
 
  private:
   struct StagingBuffer {
-    explicit StagingBuffer(const gfx::Size& size);
+    explicit StagingBuffer(const gfx::Size& size, ResourceFormat format);

[reveman, 2015/09/23 13:42:45]

nit: can remove explicit

     ~StagingBuffer();
 
     void DestroyGLResources(gpu::gles2::GLES2Interface* gl);
     void OnMemoryDump(base::trace_event::ProcessMemoryDump* pmd,
                       ResourceFormat format,
                       bool is_free) const;
 
     const gfx::Size size;
+    const ResourceFormat format;
     scoped_ptr<gfx::GpuMemoryBuffer> gpu_memory_buffer;
     base::TimeTicks last_usage;
     unsigned texture_id;
     unsigned image_id;
     unsigned query_id;
     uint64_t content_id;
   };
 
-  void AddStagingBuffer(const StagingBuffer* staging_buffer);
+  void AddStagingBuffer(const StagingBuffer* staging_buffer,
+                        ResourceFormat format);
   void RemoveStagingBuffer(const StagingBuffer* staging_buffer);
   void MarkStagingBufferAsFree(const StagingBuffer* staging_buffer);
   void MarkStagingBufferAsBusy(const StagingBuffer* staging_buffer);
   scoped_ptr<StagingBuffer> AcquireStagingBuffer(const Resource* resource,
                                                  uint64_t previous_content_id);
   base::TimeTicks GetUsageTimeForLRUBuffer();
   void ScheduleReduceMemoryUsage();
   void ReduceMemoryUsage();
   void ReleaseBuffersNotUsedSince(base::TimeTicks time);
 
@@ skipping 20 matching lines @@
 
   mutable base::Lock lock_;
   // |lock_| must be acquired when accessing the following members.
   using StagingBufferSet = std::set<const StagingBuffer*>;
   StagingBufferSet buffers_;
   using StagingBufferDeque = ScopedPtrDeque<StagingBuffer>;
   StagingBufferDeque free_buffers_;
   StagingBufferDeque busy_buffers_;
   int bytes_scheduled_since_last_flush_;
   const int max_staging_buffer_usage_in_bytes_;
+  bool use_rgba_4444_texture_format_;
   int staging_buffer_usage_in_bytes_;
   int free_staging_buffer_usage_in_bytes_;
   const base::TimeDelta staging_buffer_expiration_delay_;
   bool reduce_memory_usage_pending_;
   base::Closure reduce_memory_usage_callback_;
 
   base::WeakPtrFactory<OneCopyTileTaskWorkerPool> weak_ptr_factory_;
   // "raster finished" tasks need their own factory as they need to be
   // canceled when ScheduleTasks() is called.
   base::WeakPtrFactory<OneCopyTileTaskWorkerPool>
       task_set_finished_weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(OneCopyTileTaskWorkerPool);
 };
 
 }  // namespace cc
 
 #endif  // CC_RASTER_ONE_COPY_TILE_TASK_WORKER_POOL_H_