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/* -*- mode: C++ ; c-file-style: "stroustrup" -*- *****************************
* Qwt Widget Library
* Copyright (C) 1997 Josef Wilgen
* Copyright (C) 2002 Uwe Rathmann
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the Qwt License, Version 1.0
*****************************************************************************/
#ifndef QWT_SYSTEM_CLOCK_H
#define QWT_SYSTEM_CLOCK_H
#include "qwt_global.h"
/*!
\brief QwtSystemClock provides high resolution clock time functions.
Sometimes the resolution offered by QTime ( millisecond ) is not accurate
enough for implementing time measurements ( f.e. sampling ).
QwtSystemClock offers a subset of the QTime functionality using higher
resolution timers ( if possible ).
Precision and time intervals are multiples of milliseconds (ms).
\note The implementation uses high-resolution performance counter on Windows,
mach_absolute_time() on the Mac or POSIX timers on other systems.
If none is available it falls back on QTimer.
*/
class QWT_EXPORT QwtSystemClock
{
public:
QwtSystemClock();
virtual ~QwtSystemClock();
bool isNull() const;
void start();
double restart();
double elapsed() const;
private:
class PrivateData;
PrivateData *d_data;
};
#endif