bgfx/3rdparty/openctm/tools/systimer.cpp
2012-10-07 20:41:18 -07:00

75 lines
2.3 KiB
C++

//-----------------------------------------------------------------------------
// Product: OpenCTM tools
// File: systimer.cpp
// Description: Implementation of the system timer routines.
//-----------------------------------------------------------------------------
// Copyright (c) 2009-2010 Marcus Geelnard
//
// This software is provided 'as-is', without any express or implied
// warranty. In no event will the authors be held liable for any damages
// arising from the use of this software.
//
// Permission is granted to anyone to use this software for any purpose,
// including commercial applications, and to alter it and redistribute it
// freely, subject to the following restrictions:
//
// 1. The origin of this software must not be misrepresented; you must not
// claim that you wrote the original software. If you use this software
// in a product, an acknowledgment in the product documentation would be
// appreciated but is not required.
//
// 2. Altered source versions must be plainly marked as such, and must not
// be misrepresented as being the original software.
//
// 3. This notice may not be removed or altered from any source
// distribution.
//-----------------------------------------------------------------------------
#include "systimer.h"
using namespace std;
/// Constructor
SysTimer::SysTimer()
{
#ifdef WIN32
if(QueryPerformanceFrequency((LARGE_INTEGER *)&mTimeFreq))
QueryPerformanceCounter((LARGE_INTEGER *)&mTimeStart);
else
mTimeFreq = 0;
#else
struct timeval tv;
gettimeofday(&tv, 0);
mTimeStart = (long long) tv.tv_sec * (long long) 1000000 + (long long) tv.tv_usec;
#endif
}
/// Get current time.
double SysTimer::GetTime()
{
#ifdef WIN32
__int64 t;
QueryPerformanceCounter((LARGE_INTEGER *)&t);
return double(t - mTimeStart) / double(mTimeFreq);
#else
struct timeval tv;
gettimeofday(&tv, 0);
long long t = (long long) tv.tv_sec * (long long) 1000000 + (long long) tv.tv_usec;
return (1e-6) * double(t - mTimeStart);
#endif
}
/// Push current time (start measuring).
void SysTimer::Push()
{
mStack.push_back(GetTime());
}
/// Pop delta time since last push.
double SysTimer::PopDelta()
{
double delta = GetTime() - mStack.back();
mStack.pop_back();
return delta;
}