[fceu.git] / drivers / gp2x / throttle.c

#include <sys/time.h>
#include "main.h"
#include "gp2x.h"
#include "throttle.h"

#if 0
static uint64 tfreq;
static uint64 desiredfps;

void RefreshThrottleFPS(void)
{
 uint64 f=FCEUI_GetDesiredFPS();
 // great, a bit faster than before
 //f = (f*65) >> 6;
 desiredfps=f>>8;
 tfreq=1000000;
 tfreq<<=16;    /* Adjustment for fps returned from FCEUI_GetDesiredFPS(). */
}

static uint64 GetCurTime(void)
{
 uint64 ret;
 struct timeval tv;

 gettimeofday(&tv,0);
 ret=(uint64)tv.tv_sec*1000000;
 ret+=tv.tv_usec;
 return(ret);
}

INLINE void SpeedThrottle(void)
{
 static uint64 ttime,ltime;

 waiter:

 ttime=GetCurTime();

 if( (ttime-ltime) < (tfreq/desiredfps) )
 {
  goto waiter;
 }
 if( (ttime-ltime) >= (tfreq*4/desiredfps))
  ltime=ttime;
 else
  ltime+=tfreq/desiredfps;
}

#else

extern uint8 PAL;
extern int FSkip;
static int usec_aim = 0, usec_done = 0;
static int skip_count = 0;

INLINE void SpeedThrottle(void)
{
	static struct timeval tv_prev;
	struct timeval tv_now;
	int delta_nom = PAL ? 19997 : 16639; // ~50.007, 19.997 ms/frame : ~60.1, 16.639 ms/frame


	if (usec_done == 0) { // first time
		usec_done = 1;
		gettimeofday(&tv_prev, 0);
		return;
	}

	gettimeofday(&tv_now, 0);

	usec_aim += delta_nom;
	if (tv_now.tv_sec != tv_prev.tv_sec)
		usec_done += 1000000;
	usec_done += tv_now.tv_usec - tv_prev.tv_usec;

#ifdef FRAMESKIP
	if (Settings.frameskip >= 0)
	{
		if (skip_count >= Settings.frameskip)
			skip_count = 0;
		else {
			skip_count++;
			FSkip = 1;
		}
	}
	else if (usec_done > usec_aim + 1024*4)
	{
		/* auto frameskip */
		if (usec_done - usec_aim > 1024*32)
			usec_done = usec_aim = 1; // too much behind, try to recover..
		else
			FSkip = 1;
		tv_prev = tv_now;
		return;
	}
#endif

	tv_prev = tv_now;
	while (usec_done < usec_aim)
	{
		gettimeofday(&tv_now, 0);

		if (tv_now.tv_sec != tv_prev.tv_sec)
			usec_done += 1000000;
		usec_done += tv_now.tv_usec - tv_prev.tv_usec;
		tv_prev = tv_now;
	}
	usec_done = usec_done - usec_aim + 1; // reset to prevent overflows
	usec_aim = 0;
}
#endif
Commit	Line	Data
35868d35	1	#include <sys/time.h>
35868d35	2	#include "main.h"
b2b95d2e	3	#include "gp2x.h"
35868d35	4	#include "throttle.h"
	5
	6	#if 0
	7	static uint64 tfreq;
	8	static uint64 desiredfps;
	9
	10	void RefreshThrottleFPS(void)
	11	{
	12	uint64 f=FCEUI_GetDesiredFPS();
	13	// great, a bit faster than before
	14	//f = (f*65) >> 6;
	15	desiredfps=f>>8;
	16	tfreq=1000000;
	17	tfreq<<=16; /* Adjustment for fps returned from FCEUI_GetDesiredFPS(). */
	18	}
	19
	20	static uint64 GetCurTime(void)
	21	{
	22	uint64 ret;
	23	struct timeval tv;
	24
	25	gettimeofday(&tv,0);
	26	ret=(uint64)tv.tv_sec*1000000;
	27	ret+=tv.tv_usec;
	28	return(ret);
	29	}
	30
	31	INLINE void SpeedThrottle(void)
	32	{
	33	static uint64 ttime,ltime;
	34
	35	waiter:
	36
	37	ttime=GetCurTime();
	38
	39	if( (ttime-ltime) < (tfreq/desiredfps) )
	40	{
	41	goto waiter;
	42	}
	43	if( (ttime-ltime) >= (tfreq*4/desiredfps))
	44	ltime=ttime;
	45	else
	46	ltime+=tfreq/desiredfps;
	47	}
	48
	49	#else
	50
	51	extern uint8 PAL;
b2b95d2e	52	extern int FSkip;
35868d35	53	static int usec_aim = 0, usec_done = 0;
	54	static int skip_count = 0;
	55
	56	INLINE void SpeedThrottle(void)
	57	{
	58	static struct timeval tv_prev;
	59	struct timeval tv_now;
	60	int delta_nom = PAL ? 19997 : 16639; // ~50.007, 19.997 ms/frame : ~60.1, 16.639 ms/frame
	61
	62
	63	if (usec_done == 0) { // first time
	64	usec_done = 1;
	65	gettimeofday(&tv_prev, 0);
	66	return;
	67	}
	68
	69	gettimeofday(&tv_now, 0);
	70
	71	usec_aim += delta_nom;
	72	if (tv_now.tv_sec != tv_prev.tv_sec)
	73	usec_done += 1000000;
	74	usec_done += tv_now.tv_usec - tv_prev.tv_usec;
	75
	76	#ifdef FRAMESKIP
b2b95d2e	77	if (Settings.frameskip >= 0)
35868d35	78	{
b2b95d2e	79	if (skip_count >= Settings.frameskip)
35868d35	80	skip_count = 0;
	81	else {
	82	skip_count++;
	83	FSkip = 1;
	84	}
	85	}
937bf65b	86	else if (usec_done > usec_aim + 1024*4)
35868d35	87	{
35868d35	88	/* auto frameskip */
b2b95d2e	89	if (usec_done - usec_aim > 1024*32)
937bf65b	90	usec_done = usec_aim = 1; // too much behind, try to recover..
b2b95d2e	91	else
b2b95d2e	92	FSkip = 1;
35868d35	93	tv_prev = tv_now;
	94	return;
	95	}
	96	#endif
	97
	98	tv_prev = tv_now;
	99	while (usec_done < usec_aim)
	100	{
	101	gettimeofday(&tv_now, 0);
	102
	103	if (tv_now.tv_sec != tv_prev.tv_sec)
	104	usec_done += 1000000;
	105	usec_done += tv_now.tv_usec - tv_prev.tv_usec;
	106	tv_prev = tv_now;
	107	}
	108	usec_done = usec_done - usec_aim + 1; // reset to prevent overflows
	109	usec_aim = 0;
	110	}
	111	#endif
	112