gfx/thebes/SoftwareVsyncSource.h

   1 /* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*-
   2  * This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   5  */
   6
   7 #ifndef GFX_SOFTWARE_VSYNC_SOURCE_H
   8 #define GFX_SOFTWARE_VSYNC_SOURCE_H
   9
  10 #include "mozilla/DataMutex.h"
  11 #include "mozilla/Monitor.h"
  12 #include "mozilla/RefPtr.h"
  13 #include "mozilla/TimeStamp.h"
  14 #include "base/thread.h"
  15 #include "nsISupportsImpl.h"
  16 #include "VsyncSource.h"
  17
  18 namespace mozilla::gfx {
  19
  20 // Fallback option to use a software timer to mimic vsync. Useful for gtests
  21 // To mimic a hardware vsync thread, we create a dedicated software timer
  22 // vsync thread.
  23 class SoftwareVsyncSource : public VsyncSource {
  24  public:
  25   explicit SoftwareVsyncSource(const TimeDuration& aInitialVsyncRate);
  26   virtual ~SoftwareVsyncSource();
  27
  28   void EnableVsync() override;
  29   void DisableVsync() override;
  30   bool IsVsyncEnabled() override;
  31   bool IsInSoftwareVsyncThread();
  32   void NotifyVsync(const TimeStamp& aVsyncTimestamp,
  33                    const TimeStamp& aOutputTimestamp) override;
  34   TimeDuration GetVsyncRate() override;
  35   void ScheduleNextVsync(TimeStamp aVsyncTimestamp);
  36   void Shutdown() override;
  37
  38   // Can be called on any thread
  39   void SetVsyncRate(const TimeDuration& aNewRate);
  40
  41  protected:
  42   // Use a chromium thread because nsITimers* fire on the main thread
  43   base::Thread* mVsyncThread;
  44   RefPtr<CancelableRunnable> mCurrentVsyncTask;  // only access on vsync thread
  45   bool mVsyncEnabled;                            // Only access on main thread
  46
  47  private:
  48   DataMutex<TimeDuration> mVsyncRate;  // can be accessed on any thread
  49 };
  50
  51 }  // namespace mozilla::gfx
  52
  53 #endif /* GFX_SOFTWARE_VSYNC_SOURCE_H */