frame pacing with gamescope wsi layer is broken in some games

[Cristalx11]

Like I said in the title, I have a little problem that gave me a lot of headaches. I have a LCD Deck with 70hz screen overclock. If a game is in native resolution (1280x800), the overlays shows like frames should be generated at x2 but it looks exactly like the fps I have without fg, in this case rdr 2, caped at 35fps with vsync set to half and no visual artifacts. It stays at 70fps. If I enable x3, it looks like its working, smoother and some visual artifacts but it doesnt look like 70hz and more like it shows (105fps). It looks more like 45-50 fps. If I go to x4, smooth fps but a lot of visual artifacts and high latency. It also works if I drop the resolution a little lower, enough to have any type of black bars if scaling is set to integer. I choose 1152x720. If its set to integer and scalling to linear, it doesnt work but the moment I sellect any other scalling mode and filter, it works, flawlessly, verry low input lag, few visual artifacts and steady 70fps with dips to 65fps. This time looks and feels that its working. You can say that I can use a lower resolution and call it a day. But me? No. Headache part. I tryed to fidle with gamescope rendering. Changed resolutions in a lot of ways. Took me 2 days of testing to finally give up. Any resolution I tryed, only just using gamescope -r resulted in flikering. The fun part is that it worked, with flikering it was working at native resolution. Didn't matter if I used the decky plugin or just command so I used the plugin for convenience. I got to this final command when I gave up: ~/lsfg -- gamescope -W 1280 -H 800 -f -- %command%. Lsfg first because it doesnt work if it was after gamescope and "--" was verry important, otherwise it crash. I saw on youtube some that say it works but have the same problem like me and they just dont see, no artifacts and exact motion smoothness in 60fps youtube videos. So, maybe this is a bug and I would be verry happy to help testing any type of fix. Until then I will use 1152x720. Sorry for the long pharagraph and thank you!

[MrCoasterBrain]

I had the same problem, but it looks like the guy in this video was able to find a temporary solution:
https://www.youtube.com/watch?v=LGJFkaR250U&t=443s

[PancakeTAS]

This is such a weird issue and I've been getting many reports about it. I can't replicate it in any of my games but I'll keep trying I guess.

[Cristalx11]

I tryed to use higher resolution and didnt work.
And with gamescope command it have some strange interference but close to a fix.
So I found some kind of fix. Not good but close.
Launch option: ~/lasfg -- gamescope -w 1280 -h 800 -r 70 -f -- %command%
Lsfg set to 40-50% flow, performance deactivated.

-f so gamescope is set to fullscreen so the overlay doesnt flicker, -w and -h to set resolution othewise it will be set to 1280x720 and -r to set refresh rate (optional)

All framerate is reported double than real. V-sync is set to half

2 videos:

https://mega.nz/file/uJ8lhBDQ#1hvdj1cUE5lZvxyCJryQfOJe0l4ZcCppBbQ0UttWdco

https://mega.nz/file/PMcGSJKQ#hVjEUhYWCNIimdOtZ_bQJZuaR38h1PsLVnQFFzwxW9A

[Saigaiii]

The way I have been able to get it work on steam deck is via mangohud. Don’t know why x2 only works with mangohud in the command line in game mode on steam deck, but that’s just how it is ig. Also need to hide the mangohud overlay with a specific launch option, which should’ve easy to find online. If not it’s in the decky plugin wiki.

[Cristalx11]

How did you use mangohud to fix? I tryed mangohud ~/lsfg %command% and ~/lsfg mangohud %command% and none worked. I even used it with gamescope. It generate frames for mangohud overlay as well 😂

[PancakeTAS]

try MANGOHUD=1 ~/lsfg %command%

[Saigaiii]

Just copied and pasted the command in the lsfg vk decky plug-in’s wiki that has mangohud along with the command to hide it. It fixed the game not feeling like 60 fps for me.

[Cristalx11]

Nope. Still no luck

Update: in desktop mode works. Fullscreen 1280x800. Lsfg 2x

[PancakeTAS]

After a bunch of testing in the discord I've kind of figured out where the issue is?
Turns out gamescope's "vsync" doesn't actually do the "vsyncing" properly? I don't know if it's gamescope or some other component in the stack.
Adding various Vulkan layers ontop of each other (in my case VK_INSTANCE_LAYERS=VK_LAYER_KHRONOS_validation MANGOHUD=1) does for some reason work around the issue? No idea why, but that'll have to do for now.
I won't be fixing this issue before 1.0 because it requires a major rewrite..