New SteamVR Beta has some essential Half-Life: Alyx fixes for Linux

Quoting: CyberRat

Quoting: slaapliedjeI do know that Elite ran at about 100fps less than it does on Windows, and in VR, that kills your stomach when you try to maneuver in a space station!.

Elite Dangerous? since when does that run on linux?

It has been running for a while now. Amazing, right? It does work in VR, just needs more performance. Though I don't think I have tried it since Proton 5.0+

Quoting: EhvisAlso, I'm running on Nvidia and while it has specific issues with reprojection, it can still be made to work reasonable well. It takes a bit of research and configuration, but nothing that hasn't been know for a year.

Any pointers? I get terrible stutter in Alyx I could do without.

Quoting: damarrin

Quoting: EhvisAlso, I'm running on Nvidia and while it has specific issues with reprojection, it can still be made to work reasonable well. It takes a bit of research and configuration, but nothing that hasn't been know for a year.

Any pointers? I get terrible stutter in Alyx I could do without.

There are two major problems with reprojection on nvidia (well, at least on nvidia). Reprojected frames aren't correct, they appear like some sort of badly interpolated frame and as a solution they're worse than the problem. Second, for some reason reprojected frames appear to be injected even when frame times are consistently below the limit. So basically you need to avoid reprojection at all cost.

Things to do:
- Turn reprojection to "legacy". I'm not exactly sure what legacy is, but it seems to get rid of the unnecessary reprojection frames.
- Set your Index to 80 Hz so you have a bit more time for your frames. Trust me, the change to 80 Hz is minor compared to reprojection.
- Change your settings so that you don't exceed 12.5 ms frame times. In SteamVR you can set the rendering resolution. Seems to default to 150%, but lowering it to 100% seems to barely affect quality. This will mostly affect GPU load. Other than that, you need to experiment with the game settings. You may need to find some stuff to get the CPU load down as well.

Obviously there are also unsolvable problems. Proton shader compilation stutters are always a thing. I rarely see any shader downloads in Steam for VR games. Some games are just badly made. It requires quite a bit of expertise to make a game with stable frame times. A lot of stuff is just slapped together in Unity without thinking and it's a mess. And since we don't have motion smoothing to "fix" things, it will remain bad.


Edit:
Two other side points.
- Things seem to be very dependent on compositors. I think mutter is fine, but some definitely affect VR.
- Having a GSYNC display is a big issue. GSYNC (even after the so called fix) needs to be forced off with an "nvidia-settings" command (turning it off through the GUI is not enough).


Last edited by Ehvis on 28 March 2020 at 9:49 am UTC

Thanks, I'll try all that. I do remember setting 80 Hz being better, but then I saw my frame times well within the limit and put it higher. I have legacy on, it helps or maybe doesn't, it's hard to tell. Looks like I have my work cut out for me. :-)