/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

/* vim: set ts=8 sts=2 et sw=2 tw=80: */

/* This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef MOZILLA_LAYERS_PAINTTHREAD_H

#define MOZILLA_LAYERS_PAINTTHREAD_H

#include "base/platform_thread.h"

#include "mozilla/RefPtr.h"

#include "mozilla/StaticPtr.h"

#include "mozilla/UniquePtr.h"

#include "mozilla/layers/TextureClient.h"

#include "RotatedBuffer.h"

#include "nsThreadUtils.h"

class nsIThreadPool;

namespace mozilla {

namespace gfx {

class DrawTarget;

class DrawTargetCapture;

};

namespace layers {

// A paint task contains a description of a rasterization work to be done

// on the paint thread or paint worker pool.

//

// More specifically it contains:

// 1. A capture command list of drawing commands

// 2. A destination draw target to replay the draw commands upon

// 3. A list of dependent texture clients that must be kept alive for the

//    task's duration, and then destroyed on the main thread

class PaintTask {

public:

  PaintTask() {}

  ~PaintTask() {}

  void DropTextureClients();

  RefPtr<gfx::DrawTarget> mTarget;

  RefPtr<gfx::DrawTargetCapture> mCapture;

  AutoTArray<RefPtr<TextureClient>, 4> mClients;

};

class CompositorBridgeChild;

class PaintThread final

{

  friend void DestroyPaintThread(UniquePtr<PaintThread>&& aPaintThread);

public:

  static void Start();

  static void Shutdown();

  static PaintThread* Get();

  // Helper for asserts.

  static bool IsOnPaintThread();

  bool IsOnPaintWorkerThread();

  // This allows external users to run code on the paint thread.

  void Dispatch(RefPtr<Runnable>& aRunnable);

  // This allows the paint thread to dynamically toggle between a paint worker

  // thread pool used with tiling, and a single paint thread used with rotated

  // buffer.

  void UpdateRenderMode();

  // Must be called on the main thread. Queues an async paint

  // task to be completed on the paint thread.

  void QueuePaintTask(UniquePtr<PaintTask>&& aTask);

  // Must be called on the main thread. Signifies that the current

  // layer tree transaction has been finished and any async paints

  // for it have been queued on the paint thread. This MUST be called

  // at the end of a layer transaction as it will be used to do an optional

  // texture sync and then unblock the main thread if it is waiting to paint

  // a new frame.

  void QueueEndLayerTransaction(SyncObjectClient* aSyncObject);

  // Sync Runnables need threads to be ref counted,

  // But this thread lives through the whole process.

  // We're only temporarily using sync runnables so

  // Override release/addref but don't do anything.

  void Release();

  void AddRef();

  static int32_t CalculatePaintWorkerCount();

private:

  PaintThread();

  bool Init();

  void ShutdownOnPaintThread();

  void InitOnPaintThread();

  void InitPaintWorkers();

  void AsyncPaintTask(CompositorBridgeChild* aBridge,

                      PaintTask* aTask);

  void AsyncEndLayerTransaction(CompositorBridgeChild* aBridge);

  static StaticAutoPtr<PaintThread> sSingleton;

  static StaticRefPtr<nsIThread> sThread;

  static PlatformThreadId sThreadId;

  RefPtr<nsIThreadPool> mPaintWorkers;

};

} // namespace layers

} // namespace mozilla

#endif