High-precision time

[Josh]

This is what I use for some internal timing stuff:
 

#ifdef _WIN32
	double PCFreq = 0.0;
	__int64 CounterStart = 0;
	bool counterstarted = false;
#endif

	double fMillisecs()
	{
#ifdef _WIN32
		//return GetTickCount64(); // this only updates every 16 milliseconds, don't use it!
		//return timeGetTime();
		if (!counterstarted)
		{
			LARGE_INTEGER li;
			QueryPerformanceFrequency(&li);
			PCFreq = double(li.QuadPart) / 1000.0;
			QueryPerformanceCounter(&li);
			CounterStart = li.QuadPart;
			counterstarted = true;
		}
		LARGE_INTEGER li;
		QueryPerformanceCounter(&li);
		//return (((double(li.QuadPart - CounterStart) / PCFreq) * 1000.0)) / 1000.0;
		return double(li.QuadPart - CounterStart) / PCFreq;
#else
		long t;
		struct timeval tv;
		gettimeofday(&tv, 0);
		long secstomillisecs = 1000;
		t = tv.tv_sec * secstomillisecs;
		t += tv.tv_usec / 1000.0;
		return t;
#endif
	}

 

[Dreikblack]

Thats what Canardia uses, but i was not sure if it's fine to use for not profiling purposes but i see it is now. His code:

// Stopwatch.h
#pragma once
class Stopwatch
{
public:
    LARGE_INTEGER StartTime, Frequency, StopTime, ElapsedTime;
    Stopwatch();
    void Start();
    double Elapsed();
};

// Stopwatch.cpp
#include "UltraEngine.h"
#include "Stopwatch.h"
Stopwatch::Stopwatch()
{
    QueryPerformanceFrequency(&Frequency);
}
void Stopwatch::Start()
{
    QueryPerformanceCounter(&StartTime);
}
double Stopwatch::Elapsed()
{
    QueryPerformanceCounter(&StopTime);
    ElapsedTime.QuadPart = StopTime.QuadPart - StartTime.QuadPart;
    return (double)(ElapsedTime.QuadPart) / (Frequency.QuadPart);
}