dTimer.cpp

// LICENCE

#include "dTimer.h"

Timer::Timer()
{
        Reset();
}

Timer::~Timer()
{
}

void Timer::Reset()
{
        // Get the constant frequency
        QueryPerformanceFrequency(&mFrequency);
        QueryPerformanceCounter(&mStartTime);
        mStartTick = GetTickCount();

        mLastTime = 0;
        zeroClock = clock();
}

unsigned long Timer::GetMilliseconds()
{
        LARGE_INTEGER curTime;

        // Query the timer
        QueryPerformanceCounter(&curTime);
        LONGLONG newTime = curTime.QuadPart - mStartTime.QuadPart;

        // scale by 1000 for milliseconds
        unsigned long newTicks = (unsigned long) (1000 * newTime / mFrequency.QuadPart);

        // detect and compensate for performance counter leaps
        // (surprisingly common, see Microsoft KB: Q274323)
        unsigned long check = GetTickCount() - mStartTick;
        signed long msecOff = (signed long)(newTicks - check);
        if (msecOff < -100 || msecOff > 100)
        {
                // We must keep the timer running forward :)
                LONGLONG adjust = (std::min)(msecOff * mFrequency.QuadPart / 1000, newTime - mLastTime);
                mStartTime.QuadPart += adjust;
                newTime -= adjust;

                // Re-calculate milliseconds
                newTicks = (unsigned long) (1000 * newTime / mFrequency.QuadPart);
        }

        // Record last time for adjust
        mLastTime = newTime;
        return newTicks;
}

unsigned long Timer::GetMicroseconds()
{
        LARGE_INTEGER curTime;
        QueryPerformanceCounter(&curTime);
        LONGLONG newTime = curTime.QuadPart - mStartTime.QuadPart;

        // get milliseconds to check against GetTickCount
        unsigned long newTicks = (unsigned long) (1000 * newTime / mFrequency.QuadPart);

        // detect and compensate for performance counter leaps
        // (surprisingly common, see Microsoft KB: Q274323)
        unsigned long check = GetTickCount() - mStartTick;
        signed long msecOff = (signed long)(newTicks - check);
        if (msecOff < -100 || msecOff > 100)
        {
                // We must keep the timer running forward :)
                LONGLONG adjust = (std::min)(msecOff * mFrequency.QuadPart / 1000, newTime - mLastTime);
                mStartTime.QuadPart += adjust;
                newTime -= adjust;
        }

        // Record last time for adjust
    mLastTime = newTime;

        // scale by 1000000 for microseconds
        unsigned long newMicro = (unsigned long) (1000000 * newTime / mFrequency.QuadPart);
        return newMicro;
}

unsigned long Timer::GetMillisecondsCPU()
{
        clock_t newClock = clock();
        return (unsigned long)((float)(newClock-zeroClock) / ((float)CLOCKS_PER_SEC/1000.0)) ;
}

unsigned long Timer::GetMicrosecondsCPU()
{
        clock_t newClock = clock();
        return (unsigned long)((float)(newClock-zeroClock) / ((float)CLOCKS_PER_SEC/1000000.0)) ;
}