cc/resources/video_resource_updater.h

// Copyright 2013 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_RESOURCES_VIDEO_RESOURCE_UPDATER_H_
#define CC_RESOURCES_VIDEO_RESOURCE_UPDATER_H_

#include <list>
#include <vector>

#include "base/basictypes.h"
#include "base/memory/ref_counted.h"
#include "base/memory/weak_ptr.h"
#include "base/time/time.h"
#include "cc/base/cc_export.h"
#include "cc/resources/release_callback_impl.h"
#include "cc/resources/resource_format.h"
#include "cc/resources/texture_mailbox.h"
#include "ui/gfx/geometry/size.h"

namespace media {
class SkCanvasVideoRenderer;
class VideoFrame;
}

namespace cc {
class ContextProvider;
class ResourceProvider;

class CC_EXPORT VideoFrameExternalResources {
 public:
  // Specifies what type of data is contained in the mailboxes, as well as how
  // many mailboxes will be present.
  enum ResourceType {
    NONE,
    YUV_RESOURCE,
    RGB_RESOURCE,
    STREAM_TEXTURE_RESOURCE,
    IO_SURFACE,

#if defined(VIDEO_HOLE)
    // TODO(danakj): Implement this with a solid color layer instead of a video
    // frame and video layer.
    HOLE,
#endif  // defined(VIDEO_HOLE)

    // TODO(danakj): Remove this and abstract TextureMailbox into
    // "ExternalResource" that can hold a hardware or software backing.
    SOFTWARE_RESOURCE
  };

  ResourceType type;
  std::vector<TextureMailbox> mailboxes;
  std::vector<ReleaseCallbackImpl> release_callbacks;

  // TODO(danakj): Remove these too.
  std::vector<unsigned> software_resources;
  ReleaseCallbackImpl software_release_callback;

  VideoFrameExternalResources();
  ~VideoFrameExternalResources();
};

// VideoResourceUpdater is used by the video system to produce frame content as
// resources consumable by the compositor.
class CC_EXPORT VideoResourceUpdater
    : public base::SupportsWeakPtr<VideoResourceUpdater> {
 public:
  VideoResourceUpdater(ContextProvider* context_provider,
                       ResourceProvider* resource_provider);
  ~VideoResourceUpdater();

  VideoFrameExternalResources CreateExternalResourcesFromVideoFrame(
      const scoped_refptr<media::VideoFrame>& video_frame);

 private:
  struct PlaneResource {
    unsigned resource_id;
    gfx::Size resource_size;
    ResourceFormat resource_format;
    gpu::Mailbox mailbox;
    // The balance between the number of times this resource has been returned
    // from CreateForSoftwarePlanes vs released in RecycleResource.
    int ref_count;
    // These last three members will be used for identifying the data stored in
    // this resource, and uniquely identifies a media::VideoFrame plane. The
    // frame pointer will only be used for pointer comparison, i.e. the
    // underlying data will not be accessed.
    const void* frame_ptr;
    int plane_index;
    base::TimeDelta timestamp;

    PlaneResource(unsigned resource_id,
                  const gfx::Size& resource_size,
                  ResourceFormat resource_format,
                  gpu::Mailbox mailbox);
  };

  static bool PlaneResourceMatchesUniqueID(const PlaneResource& plane_resource,
                                           const media::VideoFrame* video_frame,
                                           int plane_index);

  static void SetPlaneResourceUniqueId(const media::VideoFrame* video_frame,
                                       int plane_index,
                                       PlaneResource* plane_resource);

  // This needs to be a container where iterators can be erased without
  // invalidating other iterators.
  typedef std::list<PlaneResource> ResourceList;
  ResourceList::iterator AllocateResource(const gfx::Size& plane_size,
                                          ResourceFormat format,
                                          bool has_mailbox);
  void DeleteResource(ResourceList::iterator resource_it);
  bool VerifyFrame(const scoped_refptr<media::VideoFrame>& video_frame);
  VideoFrameExternalResources CreateForHardwarePlanes(
      const scoped_refptr<media::VideoFrame>& video_frame);
  VideoFrameExternalResources CreateForSoftwarePlanes(
      const scoped_refptr<media::VideoFrame>& video_frame);

  static void RecycleResource(base::WeakPtr<VideoResourceUpdater> updater,
                              unsigned resource_id,
                              uint32 sync_point,
                              bool lost_resource,
                              BlockingTaskRunner* main_thread_task_runner);
  static void ReturnTexture(base::WeakPtr<VideoResourceUpdater> updater,
                            const scoped_refptr<media::VideoFrame>& video_frame,
                            uint32 sync_point,
                            bool lost_resource,
                            BlockingTaskRunner* main_thread_task_runner);

  ContextProvider* context_provider_;
  ResourceProvider* resource_provider_;
  scoped_ptr<media::SkCanvasVideoRenderer> video_renderer_;
  std::vector<uint8_t> upload_pixels_;

  // Recycle resources so that we can reduce the number of allocations and
  // data transfers.
  ResourceList all_resources_;

  DISALLOW_COPY_AND_ASSIGN(VideoResourceUpdater);
};

}  // namespace cc

#endif  // CC_RESOURCES_VIDEO_RESOURCE_UPDATER_H_