libretro
[Feature Request] Frame doubling/tripling with "Sync to Exact Content Framerate"
Description
It would be nice to have an option to natively double/triple the framerate of games through frame duplication.
Some VRR monitors either have really crappy LFC implementations, or they just behave weirdly at certain refresh rate ranges (anecdotally speaking, one of my older IPS displays tends to have worse image retention issues with VRR at lower refresh rates). Having the option to duplicate frames (ex: 60.01Hz -> 120.02Hz) would be nice just to avoid some of these headaches without trading away the frame pacing benefits that combining "Sync to Exact Content Framerate" and VRR provides. The only tradeoff I can think of is that frame duping would probably lead to a slight increase in input latency and system requirements, but that's about it.
Does setting vsync swap interval to 2 not do this? Or setting the subframe feature to 2?
I'm not entirely sure these options do what I'm looking for. Isn't increasing the swap interval for halving the refresh rate of the display for fixed vsync modes? (AKA, 1 frame per 2 vblank intervals?). When I enable this on one of my VRR displays, the monitor's OSD doesn't show ~120 Hz and I get really bad FreeSync flickering.
As for subframes, I didn't really try this because the tooltip recommends against using it with "Sync to Exact Content Framerate". But when I set this to 2, I don't see ~120 Hz on my OSD, and I get bad frame pacing and audio crackling (I've tried setting my vertical refresh rate to 120 Hz to "trick" the dynamic rate control, but that doesn't really help either).
