ui/compositor/compositor_observer.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef UI_COMPOSITOR_COMPOSITOR_OBSERVER_H_
   6 #define UI_COMPOSITOR_COMPOSITOR_OBSERVER_H_
   7
   8 #include "base/time/time.h"
   9 #include "ui/compositor/compositor_export.h"
  10
  11 namespace ui {
  12
  13 class Compositor;
  14
  15 // A compositor observer is notified when compositing completes.
  16 class COMPOSITOR_EXPORT CompositorObserver {
  17  public:
  18   // A commit proxies information from the main thread to the compositor
  19   // thread. It typically happens when some state changes that will require a
  20   // composite. In the multi-threaded case, many commits may happen between
  21   // two successive composites. In the single-threaded, a single commit
  22   // between two composites (just before the composite as part of the
  23   // composite cycle). If the compositor is locked, it will not send this
  24   // this signal.
  25   virtual void OnCompositingDidCommit(Compositor* compositor) = 0;
  26
  27   // Called when compositing started: it has taken all the layer changes into
  28   // account and has issued the graphics commands.
  29   virtual void OnCompositingStarted(Compositor* compositor,
  30                                     base::TimeTicks start_time) = 0;
  31
  32   // Called when compositing completes: the present to screen has completed.
  33   virtual void OnCompositingEnded(Compositor* compositor) = 0;
  34
  35   // Called when compositing is aborted (e.g. lost graphics context).
  36   virtual void OnCompositingAborted(Compositor* compositor) = 0;
  37
  38   // Called when the compositor lock state changes.
  39   virtual void OnCompositingLockStateChanged(Compositor* compositor) = 0;
  40
  41   // Called at the top of the compositor's destructor, to give observers a
  42   // chance to remove themselves.
  43   virtual void OnCompositingShuttingDown(Compositor* compositor) = 0;
  44 };
  45
  46 }  // namespace ui
  47
  48 #endif  // UI_COMPOSITOR_COMPOSITOR_OBSERVER_H_