// 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_TEST_LAP_TIMER_H_
#define CC_TEST_LAP_TIMER_H_
#include "base/time/time.h"
namespace cc {
// LapTimer is used to calculate average times per "Lap" in perf tests.
// Current() reports the time since the last call to Start().
// Store() adds the time since the last call to Start() to the accumulator, and
// resets the start time to now. Stored() returns the accumulated time.
// NextLap increments the lap counter, used in counting the per lap averages.
// If you initialize the LapTimer with a non zero warmup_laps, it will ignore
// the times for that many laps at the start.
// If you set the time_limit then you can use HasTimeLimitExpired() to see if
// the current accumulated time has crossed that threshold, with an optimization
// that it only tests this every check_interval laps.
class LapTimer {
public:
LapTimer(int warmup_laps, base::TimeDelta time_limit, int check_interval);
// Resets the timer back to it's starting state.
void Reset();
// Sets the start point to now.
void Start();
// Returns true if there are no more warmup laps to do.
bool IsWarmedUp();
// Advance the lap counter and update the accumulated time.
// The accumulated time is only updated every check_interval laps.
// If accumulating then the start point will also be updated.
void NextLap();
// Returns true if the stored time has exceeded the time limit specified.
// May cause a call to Store().
bool HasTimeLimitExpired();
// Returns true if all lap times have been timed. Only true every n'th
// lap, where n = check_interval.
bool HasTimedAllLaps();
// The average milliseconds per lap.
float MsPerLap();
// The number of laps per second.
float LapsPerSecond();
// The number of laps recorded.
int NumLaps();
private:
base::TimeTicks start_time_;
base::TimeDelta accumulator_;
int num_laps_;
int warmup_laps_;
int remaining_warmups_;
int remaining_no_check_laps_;
base::TimeDelta time_limit_;
int check_interval_;
DISALLOW_COPY_AND_ASSIGN(LapTimer);
};
} // namespace cc
#endif // CC_TEST_LAP_TIMER_H_