Timer.h

// This file is a part of the OpenSurgSim project.
// Copyright 2013, SimQuest Solutions Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#ifndef SURGSIM_FRAMEWORK_TIMER_H
#define SURGSIM_FRAMEWORK_TIMER_H

#include <boost/chrono.hpp>
#include <boost/thread/shared_mutex.hpp>
#include <deque>
#include <atomic>

namespace SurgSim
{
namespace Framework
{

class Timer
{
public:
    Timer();

    void start();

    void beginFrame();

    void endFrame();

    void markFrame();

    double getCumulativeTime() const;

    double getCurrentTime();

    double getAverageFramePeriod() const;

    double getAverageFrameRate() const;

    double getLastFramePeriod() const;

    double getLastFrameRate() const;

    void setMaxNumberOfFrames(size_t numberOfFrames);

    size_t getMaxNumberOfFrames();

    size_t getCurrentNumberOfFrames() const;

    size_t getNumberOfClockFails() const;

    double getMaxFramePeriod() const;

    double getMinFramePeriod() const;

    bool isBufferFull() const;

private:
    typedef boost::chrono::steady_clock TimerClock;

    typedef boost::chrono::duration<double> TimerDuration;

    typedef boost::chrono::time_point<TimerClock, TimerDuration> TimerTimePoint;

    TimerTimePoint now();

    static const TimerClock m_clock;

    TimerTimePoint m_lastTime;

    size_t m_maxNumberOfFrames;

    std::deque<TimerDuration> m_frameDurations;

    mutable boost::shared_mutex m_sharedMutex;

    std::atomic<size_t> m_clockFails;
};

} // Framework
} // SurgSim

#endif