scummvm/engines/lab/timing.cpp
2015-12-23 21:33:43 +01:00

130 lines
4.4 KiB
C++

/* ScummVM - Graphic Adventure Engine
*
* ScummVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
*/
/*
* This code is based on Labyrinth of Time code with assistance of
*
* Copyright (c) 1993 Terra Nova Development
* Copyright (c) 2004 The Wyrmkeep Entertainment Co.
*
*/
#include "lab/lab.h"
namespace Lab {
/*****************************************************************************/
/* Waits for for Secs seconds and Micros microseconds to pass. */
/*****************************************************************************/
void LabEngine::microDelay(uint32 secs, uint32 micros) {
uint32 waitSecs, waitMicros;
addCurTime(secs, micros, &waitSecs, &waitMicros);
while (1) {
getTime(&secs, &micros);
if ((secs > waitSecs) || ((secs == waitSecs) && (micros >= waitMicros)))
return;
g_system->delayMillis(10);
}
}
/*****************************************************************************/
/* Gets the current system time. */
/*****************************************************************************/
void LabEngine::getTime(uint32 *secs, uint32 *micros) {
uint32 t = g_system->getMillis();
*secs = t / 1000;
*micros = t % 1000;
}
/*****************************************************************************/
/* Adds seconds and microseconds to current time to get a new time. */
/*****************************************************************************/
void LabEngine::addCurTime(uint32 sec, uint32 micros, uint32 *timeSec, uint32 *timeMicros) {
getTime(timeSec, timeMicros);
(*timeSec) += sec;
(*timeMicros) += micros;
if (*timeMicros >= ONESECOND) {
(*timeSec)++;
(*timeMicros) -= ONESECOND;
}
}
/*****************************************************************************/
/* Finds the difference between time1 and time2. If time1 is later than */
/* time2, returns 0. */
/*****************************************************************************/
void LabEngine::anyTimeDiff(uint32 sec1, uint32 micros1, uint32 sec2, uint32 micros2, uint32 *diffSecs, uint32 *diffMicros) {
*diffSecs = 0;
*diffMicros = 0;
if (sec1 > sec2)
return;
else if ((sec1 == sec2) && (micros1 >= micros2))
return;
if (micros1 > micros2) {
*diffSecs = sec2 - sec1 - 1;
*diffMicros = (ONESECOND - micros1) + micros2;
} else {
*diffSecs = sec2 - sec1;
*diffMicros = micros2 - micros1;
}
}
/*****************************************************************************/
/* Finds the difference between the current time, and a future time. Returns */
/* 0 if the future time is actually before the current time. */
/*****************************************************************************/
void LabEngine::timeDiff(uint32 sec, uint32 micros, uint32 *diffSec, uint32 *diffMicros) {
uint32 curSec, curMicros;
getTime(&curSec, &curMicros);
anyTimeDiff(curSec, curMicros, sec, micros, diffSec, diffMicros);
}
/*****************************************************************************/
/* Waits for a specified time to occur. */
/*****************************************************************************/
void LabEngine::waitForTime(uint32 sec, uint32 micros) {
uint32 curSec, curMicros;
getTime(&curSec, &curMicros);
if (curSec > sec)
return;
else if ((curSec == sec) && (curMicros >= micros))
return;
if (curMicros > micros)
microDelay(sec - curSec - 1, (ONESECOND - curMicros) + micros - 1);
else
microDelay(sec - curSec, micros - curMicros - 1);
}
} // End of namespace Lab