mirror of
https://github.com/RetroPortingToolKit/psxrecomp
synced 2026-10-26 10:19:47 -04:00
Matthew Stanley
23 lines
978 B
C
23 lines
978 B
C
#ifndef PSX_PRESENT_SYNC_H
|
|
#define PSX_PRESENT_SYNC_H
|
|
|
|
/* Swap synchronization prevents tearing; the wall-clock pacer limits guest
|
|
* speed. They need not have the same rate. A faster panel can synchronize
|
|
* stock frames without becoming the guest's clock. A slower/unknown panel
|
|
* cannot block every guest frame without slowing emulation.
|
|
*
|
|
* blocked covers interpolation's own scheduler, netplay, driver recovery,
|
|
* and hosts whose swap blocking is unreliable. Mode 2 is the existing VRR
|
|
* frame-generation mode, which uses immediate swaps. */
|
|
static inline int psx_present_sync_interval(int requested, int blocked,
|
|
double guest_hz, double host_hz) {
|
|
if (blocked || (requested != 1 && requested != -1))
|
|
return 0;
|
|
if (!(guest_hz > 0.0) || !(host_hz > 0.0))
|
|
return 0;
|
|
/* Same 2% tolerance as the frontend's host/guest cadence match. */
|
|
return host_hz >= guest_hz * 0.98 ? requested : 0;
|
|
}
|
|
|
|
#endif
|