Although I have a work around, I tried to find root cause on the distortion I see when using SteamVR. Can't figure it out

I have spent hours and hours trying to figure out how to fix or find root cause or even describe the strange distortion I see while playing MSFS 2020 in VR when I run my Oculus Rift S through the SteamVR runtime rather than just through the Oculus runtime. Although I haven’t heard from others with this exact same problem, I’ve read others (not just in MSFS 2020) seemingly trying to describe the same nauseating visual behavior:

“…as though it is zooming to where I look at the same time i move.”

“…if I turn my head left and right, I feel weird, as If my eyes are slightly zooming In and Out as my head rotates.”

“…as if the VR FOV was different than the HMD FOV.”

“…it’s like my eyes are on stalks and are rotating around my head.”

If I couldn’t solve this issue just by telling OpenXR to use Oculus rather than Steam, I think I wouldn’t be able to use MSFS 2020 in VR. It is that nauseating. Since I have a work-around, the only reason I’m trying to get to the bottom of this is for the benefit of others (possibly across Oculus, WMR, and Valve headsets) who haven’t found a work-around.

I’ve pretty much given up, though, because not only can I not find root cause, I simply cannot come up with a way to SHOW the behavior for those who haven’t experienced it. I’ve tried videos and screen captures and nothing shows what my eyes and brain see. What I know is that it has nothing to do with FPS or graphic settings (turning everything down does not solve the issue). It has nothing to do with motion smoothing (AWS). It has nothing to do with Nvida driver version. The only way for me to make it come and go is to change from Steam runtime to Oculus runtime for OpenXR.

And, by the way, although it takes turning your head side-to-side in the cockpit to cause the sick feeling, this same distortion actually shows up in the menus too. As you turn your head left and right while looking at the menu, a funhouse mirror thing happens, with parallel lines becoming unparallel. It really is like the IPD or FOV or something in Steam does not match the actual setting in Oculus.

Although I can clearly see this distortion, I haven’t been able to capture the effect outside of actually wearing the headset. My last attempt to show it showed the same thing (seemingly expected behavior) on both Steam and Oculus…

Looking at a menu straight on with SteamVR has everything pretty much square in the 2D monitor view for one eye:

steam_straight_boxes

Same as Oculus:

oculus_straight_boxes

Turning your head left, predictably, causes some forced perspective in the 2D monitor view, with the right side (the “closer” side) of the menu screen appearing bigger than the left side…

Steam:
steam_look_left_boxes

Oculus:
oculus_look_left_boxes

So, I give up. Can’t find a way to make SteamVR not have the issue nor a way to make Oculus have the issue, but it is somewhat unique to me, as others don’t have a problem with SteamVR. I would have liked to get to root cause (or at least a work-around that others could maybe use for other headsets) but it’s not happening. Only sharing here in case it helps somebody else figure it out.

I had this exact same issue initially. Changing the registry for OpenXR fixed it though, so it’s strange it’s not working for you. I was running a rift cv1. I have since moved to using the G2.

@sthackrey, I wasn’t very clear, but in amongst all those words, I said that it DOES work for me to change the entry in the registry for OpenXR from Steam to Oculus. I just kept trying to find the reason for it anyway, because I thought there might be others who couldn’t do that and I’ve also heard from one G2 user who describes something similar.

So, for you, it was changing to use Oculus instead of Steam in the registry entry that fixed it? And you know the effect I mean? Very nauseating, isn’t it? I know that some users prefer using the Steam runtime, so there must be something about certain setups (I’m using the Rift S) that causes the problem.

I would like to move up to the G2, but for some silly reason, nobody has filled my pre-order(s) yet! :slight_smile: I know there are lots of tweaks and details with every headset but, in general, you just use OpenXR and WMR and things basically work?

I have the same issue on SteamVR. My current working hypothesis for the root cause is that both SteamVR and Oculus software are trying to correct twice the “inherit to VR lenses” lens distortion. If that’s the case then we can’t do a thing as SteamVR should pass the image unaltered to Oculus software and currently it seems not to be doing that.

Workaround: Use Oculus runtime.

1 Like

It’s not just you. Both my Rift CV1 and Quest 2 do this too when using the steamVR version of the openXR runtime. It’s some kind of incompatibility or bug between the Oculus host and the steamVR openXR runtime. It’s not likely to be something you can fix, as it’s bugged at the level of the openXR compatibility – the SteamVR devs, and specifically the ones working on their openXR support, would be the folks to fix it.

That said, just curious why you’re so set on using the steamVR openXR runtime instead of the Oculus one…?

1 Like

I notice it too with my Quest2 and SteamVR. There was some mention of it in the release notes for SteamVR 1.15.16 but I don’t think it was fixed - even for other Oculus HMDs:
Oculus:

  • Fixed issue with head position on Quest and Quest 2 that appeared in 1.15.15.

I like the SteamVR settings + using fpsVR with MSFS2020

2 Likes

I had the same problem and it’s gone now. If I remember right, the fix was to use the SteamVR beta instead of the released version.

I’m not sure to understand exactly the effect you’re trying to describe, I fail to also see what the pictures are illustrating, but there is also an annoying distortion with WMR and the G2 I will try to describe, it might be somehow similar.

When enabling motion reprojection with WMR OpenXR preview (v105) and using OXR Render Scaling between 50 and 60 included, the G2 is displaying the views as-if there is a larger FOV. It is like having a strong pincushion distortion (center goes smaller) and it isn’t even aligned to the head rotation position, which makes the distortion for example bigger when looking left or up than when looking right or down.

The only cure I know of for this is using at least WMR OXR Render Scale at or above 65.

2 Likes

Oh, I’m not. When I said “I give up”, I meant on finding the exact for cause or a setting that could fix/cause this behavior. I know there are some who prefer the Steam settings and tools, so I was hoping to find a fix for them.

As for actually playing and enjoying the sim, I’m definitely running the Oculus runtime! :slightly_smiling_face:

1 Like

I have this too but only when using link. If I use virtual desktop it does not have the same issue. I use steamvr as it is needed to run the game in virtual desktop.

2 Likes

Indeed, my main frustration in this investigation has been that I can’t find a way to show others what it looks like. :slightly_smiling_face:

The pictures, frustratingly enough after I spent so much time on them, illustrate nothing! They show only that Steam and Oculus both display only normal, expected perspective when turning my head. The pictures just show this perspective in action, using the perfectly square colored rectangles to show the change in shape of the menus.

Thank you for that! The reason I started on this investigation was to try to help a G2 user! I will pass this along.

1 Like

Yup, same here. I don’t know exactly how Virtual Desktop does its wizardry, but I think it’s using parts of the Oculus runtime that are for Rift/RiftS rather than Quest/Link, and it’s doing frame capture on that with its own streamer, which is a lot more efficient than Oculus’ Link streamer. If VD could support ASW or motion smoothing, I don’t think I’d have any reason to bother with Link at all anymore, but unfortunately the dev himself said this is unlikely to ever happen.

I Duckduck:ed myself to this thread. I too experience the same issue with the right eye being “lazy” the closer an item is in the world, making me quite cross-eyed. The error was as pointed out above that Steam VR was running.

Good to know I 'm not alone. And thanks for the “fix” :slight_smile:

Hi, thanks for posting this. I too had this problem and really appreciate the answer that the render scale needs to be 65 or above. I only tried going lower after this guy’s video where he says it’s best at 50:

He has some decent tips but this was a real pitfall and I was struggling with the problem for a while until I stumbled upon your post here.

YT videos are more often that not honey pots for clicks unfortunately.

Instead, you might want to read this discussion, it might help you (or not):

My 2070 SUPER VR settings and suggestion (Reverb G2 - WMR)

This topic was automatically closed 30 days after the last reply. New replies are no longer allowed.