Adam Barth 70604d6c23 Add a simple scheduler for animation frames
This CL adds a simple scheduler for animation frames that holds a given interval
in a given phase.  The scheduler can be told the estimated duration of the
BeginFrame callback and can adjust the callback to hit a given vsync interval.

This CL also makes ganesh_app use this scheduler to animate.

R=jamesr@chromium.org, ernstm@chromium.org

Review URL: https://codereview.chromium.org/731893002
2014-11-17 11:24:07 -08:00

53 lines
1.2 KiB
C++

// 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 SKY_SCHEDULER_TIMER_H_
#define SKY_SCHEDULER_TIMER_H_
#include "base/memory/weak_ptr.h"
#include "base/single_thread_task_runner.h"
#include "base/time/time.h"
#include "sky/scheduler/time_interval.h"
namespace sky {
class Timer {
public:
class Client {
public:
virtual void OnTimerTick(base::TimeTicks now) = 0;
protected:
virtual ~Client();
};
Timer(Client* client,
scoped_refptr<base::SingleThreadTaskRunner> task_runner);
~Timer();
void SetInterval(const TimeInterval& parameters);
void SetEnabled(bool enabled);
private:
base::TimeTicks NextTickTarget(base::TimeTicks now);
void ScheduleNextTick(base::TimeTicks now);
void PostTickTask(base::TimeTicks now, base::TimeTicks target);
void OnTimerFired();
Client* client_;
scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
TimeInterval interval_;
base::TimeTicks last_tick_;
base::TimeTicks current_target_;
bool enabled_;
base::WeakPtrFactory<Timer> weak_factory_;
};
}
#endif // SKY_SCHEDULER_TIMER_H_