/*
 * Copyright 2009, Ingo Weinhold, ingo_weinhold@gmx.de.
 * Distributed under the terms of the MIT License.
 */
#ifndef TIME_COMPUTER_H
#define TIME_COMPUTER_H


#include <SupportDefs.h>


struct TimeComputer {
                                                                TimeComputer();

                        void                            Init(float frameRate, bigtime_t realBaseTime);
                        void                            SetFrameRate(float frameRate);

                        void                            AddTimeStamp(bigtime_t realTime, uint64 frames);

                        bigtime_t                       RealTime() const        { return fRealTime; }
                        bigtime_t                       PerformanceTime() const
                                                                        { return fPerformanceTime; }
                        double                          Drift() const           { return fDrift; }

private:
        static  const int32                     kEntryCount = 32;

                        struct Entry {
                                bigtime_t       realTime;
                                bigtime_t       performanceTime;
                        };

private:
                        void                            _AddEntry(bigtime_t realTime,
                                                                        bigtime_t performanceTime);

private:
                        bigtime_t                       fRealTime;
                        bigtime_t                       fPerformanceTime;
                        double                          fDrift;
                        float                           fFrameRate;
                        double                          fUsecsPerFrame;
                        bigtime_t                       fPerformanceTimeBase;
                        uint64                          fFrameBase;
                        bool                            fResetTimeBase;
                        Entry                           fEntries[kEntryCount];
                        int32                           fFirstEntry;
                        int32                           fLastEntry;
};


#endif  // TIME_COMPUTER_H