/***************************************************************************
fps.c - description
-------------------
begin : Sun Oct 28 2001
copyright : (C) 2001 by Pete Bernert
email : BlackDove@addcom.de
***************************************************************************/
/***************************************************************************
* *
* 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. See also the license.txt file for *
* additional informations. *
* *
***************************************************************************/
// FPS stuff
float fFrameRateHz=0;
DWORD dwFrameRateTicks=16;
float fFrameRate=200.0f;
int iFrameLimit=2;
int UseFrameLimit=0;
int UseFrameSkip=0;
// FPS skipping / limit
BOOL bInitCap = TRUE;
float fps_skip = 0;
float fps_cur = 0;
#define TIMEBASE 100000
#define MAXLACE 16
#define MAXSKIP 120
static void calcfps(void);
static void FrameCap(void);
void CheckFrameRate(void)
{
if(UseFrameSkip) // skipping mode?
{
if(!(dwActFixes&0x80)) // not old skipping mode?
{
dwLaceCnt++; // -> store cnt of vsync between frames
if(dwLaceCnt>=MAXLACE && UseFrameLimit) // -> if there are many laces without screen toggling,
{ // do std frame limitation
if(dwLaceCnt==MAXLACE) bInitCap=TRUE;
FrameCap();
}
}
else if(UseFrameLimit) FrameCap();
calcfps(); // -> calc fps display in skipping mode
}
else // non-skipping mode:
{
if(UseFrameLimit) FrameCap(); // -> do it
calcfps(); // -> and calc fps display
}
}
static unsigned long timeGetTime(void)
{
struct timeval tv;
gettimeofday(&tv, 0); // well, maybe there are better ways
return tv.tv_sec * 100000 + tv.tv_usec/10; // to do that, but at least it works
}
static void FrameCap (void)
{
static unsigned long curticks, lastticks, _ticks_since_last_update;
static unsigned int TicksToWait = 0;
int overslept=0, tickstogo=0;
BOOL Waiting = TRUE;
{
curticks = timeGetTime();
_ticks_since_last_update = curticks - lastticks;
if((_ticks_since_last_update > TicksToWait) ||
(curticks <lastticks))
{
lastticks = curticks;
overslept = _ticks_since_last_update - TicksToWait;
if((_ticks_since_last_update-TicksToWait) > dwFrameRateTicks)
TicksToWait=0;
else
TicksToWait=dwFrameRateTicks - overslept;
}
else
{
while (Waiting)
{
curticks = timeGetTime();
_ticks_since_last_update = curticks - lastticks;
tickstogo = TicksToWait - _ticks_since_last_update;
if ((_ticks_since_last_update > TicksToWait) ||
(curticks < lastticks) || tickstogo < overslept)
{
Waiting = FALSE;
lastticks = curticks;
overslept = _ticks_since_last_update - TicksToWait;
TicksToWait = dwFrameRateTicks - overslept;
return;
}
if (tickstogo >= 200 && !(dwActFixes&16))
usleep(tickstogo*10 - 200);
}
}
}
}
static void FrameSkip(void)
{
static int iNumSkips=0,iAdditionalSkip=0; // number of additional frames to skip
static DWORD dwLastLace=0; // helper var for frame limitation
static DWORD curticks, lastticks, _ticks_since_last_update;
int tickstogo=0;
static int overslept=0;
if(!dwLaceCnt) return; // important: if no updatelace happened, we ignore it completely
if(iNumSkips) // we are in skipping mode?
{
dwLastLace+=dwLaceCnt; // -> calc frame limit helper (number of laces)
bSkipNextFrame = TRUE; // -> we skip next frame
iNumSkips--; // -> ok, one done
}
else // ok, no additional skipping has to be done...
{ // we check now, if some limitation is needed, or a new skipping has to get started
DWORD dwWaitTime;
if(bInitCap || bSkipNextFrame) // first time or we skipped before?
{
if(UseFrameLimit && !bInitCap) // frame limit wanted and not first time called?
{
DWORD dwT=_ticks_since_last_update; // -> that's the time of the last drawn frame
dwLastLace+=dwLaceCnt; // -> and that's the number of updatelace since the start of the last drawn frame
curticks = timeGetTime(); // -> now we calc the time of the last drawn frame + the time we spent skipping
_ticks_since_last_update= dwT+curticks - lastticks;
dwWaitTime=dwLastLace*dwFrameRateTicks; // -> and now we calc the time the real psx would have needed
if(_ticks_since_last_update<dwWaitTime) // -> we were too fast?
{
if((dwWaitTime-_ticks_since_last_update)> // -> some more security, to prevent
(60*dwFrameRateTicks)) // wrong waiting times
_ticks_since_last_update=dwWaitTime;
while(_ticks_since_last_update<dwWaitTime) // -> loop until we have reached the real psx time
{ // (that's the additional limitation, yup)
curticks = timeGetTime();
_ticks_since_last_update = dwT+curticks - lastticks;
}
}
else // we were still too slow ?!!?
{
if(iAdditionalSkip<MAXSKIP) // -> well, somewhen we really have to stop skipping on very slow systems
{
iAdditionalSkip++; // -> inc our watchdog var
dwLaceCnt=0; // -> reset lace count
lastticks = timeGetTime();
return; // -> done, we will skip next frame to get more speed
}
}
}
bInitCap=FALSE; // -> ok, we have inited the frameskip func
iAdditionalSkip=0; // -> init additional skip
bSkipNextFrame=FALSE; // -> we don't skip the next frame
lastticks = timeGetTime(); // -> we store the start time of the next frame
dwLaceCnt=0; // -> and we start to count the laces
dwLastLace=0;
_ticks_since_last_update=0;
return; // -> done, the next frame will get drawn
}
bSkipNextFrame=FALSE; // init the frame skip signal to 'no skipping' first
curticks = timeGetTime(); // get the current time (we are now at the end of one drawn frame)
_ticks_since_last_update = curticks - lastticks;
dwLastLace=dwLaceCnt; // store curr count (frame limitation helper)
dwWaitTime=dwLaceCnt*dwFrameRateTicks; // calc the 'real psx lace time'
if (dwWaitTime >= overslept)
dwWaitTime-=overslept;
if(_ticks_since_last_update>dwWaitTime) // hey, we needed way too long for that frame...
{
if(UseFrameLimit) // if limitation, we skip just next frame,
{ // and decide after, if we need to do more
iNumSkips=0;
}
else
{
iNumSkips=_ticks_since_last_update/dwWaitTime; // -> calc number of frames to skip to catch up
iNumSkips--; // -> since we already skip next frame, one down
if(iNumSkips>MAXSKIP) iNumSkips=MAXSKIP; // -> well, somewhere we have to draw a line
}
bSkipNextFrame = TRUE; // -> signal for skipping the next frame
}
else // we were faster than real psx? fine :)
if(UseFrameLimit) // frame limit used? so we wait til the 'real psx time' has been reached
{
if(dwLaceCnt>MAXLACE) // -> security check
_ticks_since_last_update=dwWaitTime;
while(_ticks_since_last_update<dwWaitTime) // -> just do a waiting loop...
{
curticks = timeGetTime();
_ticks_since_last_update = curticks - lastticks;
tickstogo = dwWaitTime - _ticks_since_last_update;
if (tickstogo-overslept >= 200 && !(dwActFixes&16))
usleep(tickstogo*10 - 200);
}
}
overslept = _ticks_since_last_update - dwWaitTime;
if (overslept < 0)
overslept = 0;
lastticks = timeGetTime(); // ok, start time of the next frame
}
dwLaceCnt=0; // init lace counter
}
static void calcfps(void)
{
static unsigned long curticks,_ticks_since_last_update,lastticks;
static long fps_cnt = 0;
static unsigned long fps_tck = 1;
static long fpsskip_cnt = 0;
static unsigned long fpsskip_tck = 1;
{
curticks = timeGetTime();
_ticks_since_last_update=curticks-lastticks;
if(UseFrameSkip && !UseFrameLimit && _ticks_since_last_update)
fps_skip=min(fps_skip,((float)TIMEBASE/(float)_ticks_since_last_update+1.0f));
lastticks = curticks;
}
if(UseFrameSkip && UseFrameLimit)
{
fpsskip_tck += _ticks_since_last_update;
if(++fpsskip_cnt==2)
{
fps_skip = (float)2000/(float)fpsskip_tck;
fps_skip +=6.0f;
fpsskip_cnt = 0;
fpsskip_tck = 1;
}
}
fps_tck += _ticks_since_last_update;
if(++fps_cnt==20)
{
fps_cur = (float)(TIMEBASE*20)/(float)fps_tck;
fps_cnt = 0;
fps_tck = 1;
}
}
static void PCFrameCap (void)
{
static unsigned long curticks, lastticks, _ticks_since_last_update;
static unsigned long TicksToWait = 0;
BOOL Waiting = TRUE;
while (Waiting)
{
curticks = timeGetTime();
_ticks_since_last_update = curticks - lastticks;
if ((_ticks_since_last_update > TicksToWait) ||
(curticks < lastticks))
{
Waiting = FALSE;
lastticks = curticks;
TicksToWait = (TIMEBASE/ (unsigned long)fFrameRateHz);
}
}
}
static void PCcalcfps(void)
{
static unsigned long curticks,_ticks_since_last_update,lastticks;
static long fps_cnt = 0;
static float fps_acc = 0;
float CurrentFPS=0;
curticks = timeGetTime();
_ticks_since_last_update=curticks-lastticks;
if(_ticks_since_last_update)
CurrentFPS=(float)TIMEBASE/(float)_ticks_since_last_update;
else CurrentFPS = 0;
lastticks = curticks;
fps_acc += CurrentFPS;
if(++fps_cnt==10)
{
fps_cur = fps_acc / 10;
fps_acc = 0;
fps_cnt = 0;
}
fps_skip=CurrentFPS+1.0f;
}
void SetAutoFrameCap(void)
{
if(iFrameLimit==1)
{
fFrameRateHz = fFrameRate;
dwFrameRateTicks=(TIMEBASE*100 / (unsigned long)(fFrameRateHz*100));
return;
}
if(dwActFixes&32)
{
if (PSXDisplay.Interlaced)
fFrameRateHz = PSXDisplay.PAL?50.0f:60.0f;
else fFrameRateHz = PSXDisplay.PAL?25.0f:30.0f;
}
else
{
fFrameRateHz = PSXDisplay.PAL?50.0f:59.94f;
dwFrameRateTicks=(TIMEBASE*100 / (unsigned long)(fFrameRateHz*100));
}
}
static void InitFPS(void)
{
if(!fFrameRate) fFrameRate=200.0f;
if(fFrameRateHz==0) fFrameRateHz=fFrameRate; // set user framerate
dwFrameRateTicks=(TIMEBASE / (unsigned long)fFrameRateHz);
}