ffgl-host/OSXTimer.cpp at master · cyrilcode/ffgl-host · GitHub

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#include"Timer.h"
#include<mach/mach.h>
#include<mach/mach_time.h>

classOSXTimer :
public Timer
{
public:

OSXTimer()
 :m_startTime(0)
 {
//make sure we query the timebase before doing any timing
if (g_firstTime==0)
 {
 g_firstTime = 1;

mach_timebase_info_data_t timebase;

mach_timebase_info(&timebase);

 g_conversion = (1.0 / 1000000000.0) * ((double)timebase.numer / (double)timebase.denom );
 }

//start the timer now
 m_startTime = mach_absolute_time();
 }

staticint g_firstTime;
staticdouble g_conversion;

uint64_t m_startTime;

voidReset()
 {
//restart the timer now
 m_startTime = mach_absolute_time();
 }

doubleGetElapsedTime()
 {
//whats the current time?
uint64_t curTime = mach_absolute_time();

uint64_t elapsed = curTime - m_startTime;

return g_conversion * (double)elapsed;
 }

virtual~OSXTimer()
 {}
};

int OSXTimer::g_firstTime = 0;
double OSXTimer::g_conversion = 0.0;

Timer *Timer::New()
{
returnnewOSXTimer();
}