48 lines
1.3 KiB
C++
48 lines
1.3 KiB
C++
/* -*- 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
|