Quest 3 new feature "Positional Time Warp"

User Support Hub Virtual Reality (VR)
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In the latest v83 update, Meta introduced an experimental feature called “Positional Time Warp” that enhances VR smoothness by applying positional adjustments (beyond just rotation) to frames when games struggle to keep up, reducing judder and making movement feel more stable by using depth data.

Try to activate it in the experimental settings in Quest 3 config, and set Motion Smoothing to “DEPTH” in the sim. For me it makes wonders, I have been always plagued by judders and stutters while turning head in the cockpit but this made all smooth as butter and stutters disappeared.

I’m using Virtual Desktop with a Quest 3, 80HZ, ASW always on, Godlike mode. (Ryzen 9 9950X3D, RTX5080)

Please try it for yourself and report, i haven’t find any drawbacks so far.

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it doesn t work in PCVR mode

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Thanks for tip…I’ll give it a go later.

Bought my Q3 about 7 months ago….I reckon the image clarity is improving after every update? Or is it just wishful thinking?

I tried a Pimax Super…but as I’m running a 4080Super, the card just was not powerful enough to get the best out of the Pimax, plus there were a number of other features that I didn’t enjoy….so back it went. Quite happy with the Q3 at the moment.

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Try it, for me in Virtual Desktop it brings a noticeable improvement in smoothness

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Just quickly tried it and it is definitely very smooth, all though it is hard to tell if it is better than without it as SU4 is already very smooth for me. Will keep in enabled for the next couple of flights I do to see how it goes, especially on approach to a complex airport.

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Ya, I don’t see any difference with experimental positional time warp enabled with my Q3 with msfs2020/2024. Also, I’ve never seen any improvement using depth motion reproduction in either sim.

The only meta standalone home settings that seem to transfer over well are your brightness/contrast settings. I’ve found it best to pick a darkish standalone home environment and then adjust brightness/contrast to give the best overall results. Everyone’s eyes are different but, for me, this is ~85% brightness with the contrast slider just a tad to the right of full left (= default).

The experimental content adaptive brightness may carry over into PCVR but the differences don’t seem significant, so maybe just a placebo thing?

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Can’t say I noticed much difference to be honest, but it certainly didn’t make things any worse. At one point I was trying to convince myself the double vision on runway lights when looking sideways was reduced but it came back as I sped up. Still get occasional judders and stutters but I think that’s just the nature of the beast - it’s impossible to eliminate them entirely.

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The Depth option in MSFS does absolutely nothing with Virtual Desktop. We don’t stream the depth buffer to the headset, where the PTW would happen. You are victim of a placebo effect.

Source: I’m the developer of the Virtual Desktop OpenXR support.

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This was the kind of feedback i was hoping to have. :grinning_face_with_smiling_eyes: I would like to take this opportunity to thank you for everything you have done for us VR users. :+1:

I knew that VD did not use the depth buffer (That’s why i always played with motion smoothing = off.) but i was wondering if it was able to pass it to the headset, so the answer is no.

However something is going on when enabling PTW in the headset, it seems to work for all apps (as reported in other forums) and in my case and my PC config i can assure it’s not a placebo: head movements feel more responsive (less lag) and i get a lot less judders/stutters. Didnt try with motion smoothing = off but at this point this should be ininfluent.

That’s why i asked for other feedbacks, it seems this does not benefit everyone.

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Still a placebo thing imho with both my Q3 and QPro v83, using Link or Air Link. However, if you think it helps, that’s great mate. Cheers.

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I’ve finally caught up on the release notes for this:

System Positional TimeWarp (PTW)

We’re introducing System Positional TimeWarp (SysPTW) from Depth-From-Stereo to Quest headsets. PTW uses real-time scene depth to reduce visual judder and lag when apps drop frames, making movement in VR smoother and more comfortable. This feature automatically activates when needed and works across all apps, with no impact on regular performance. You can expect a more stable experience, especially in demanding social and gaming apps

So basically what’s happening here is the Quest uses the motion estimation engine on the XR2 to perform depth estimation using stereo images. If you have a stereo image and look at an object, you can measure the “distance” between that object in the left view and the right view. Now, accounting for your IPD, use that distance to determine the distance between you and the object (aka, the depth). It’s an imperfect process but works surprisingly well (unless you have a lot of transparency, like a glass cockpit).

This depth is then used for better spatial reprojection (Timewarp in Meta speak). In particular, it helps creating better perspective when translating your head (as opposed to traditional Timewarp that only accounts for rotation of the head). With streaming apps, when no depth is being streamed (none of the streamers do it), this could possibly improve quality.

Here is an experiment to run, now that you understand better what it does.

  1. Pick an object near you (as opposed to something very far out in the landscape). I like to pick the “frame” of the plane, while sitting in the cockpit.

  2. Now move your head at medium speed from left to right and back, while looking at the object (here the frame of the plane).

If you are not hitting the refresh rate (and you are not, because this is MSFS :D) and any form of motion reprojection (ASW, SSW) is turned off, you should clearly see the “juddering” of not meeting the refresh rate. This is every other image (more or less) being reprojected instead of being rendered at the correct pose.

Now compare how noticeable is the juddering with and without that PTW option enabled.

I haven’t tested that myself with the new PTW option, but hopefully that helps figuring out placebo or not!

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Excuse my ignorance, but how do you set “Motion Smoothing” to DEPTH in the (MSFS2024)?

Cheers

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In VR Graphics settings submenu.

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Tested this on/off with my Q3 using Air Link and QPro using Link. I did not notice any differences either way. Likewise with depth reprojection depth/off, although turning this off seemed to result in everything a bit smoother, so I’ll continue to leave that off.

While I didn’t see any benefits with PTW enabled, I didn’t see any downside while enabled. So, I’ll probably just leave it enabled for now. Like everything PCVR, your results may vary depending on your PC setup and where/how your fly, Thanks for your detailed explanation on all this mate and best Xmas cheers.

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Same results here with QPro. I can’t detect any differences with on/off.

I’m sure I read somewhere that this tech only applied to local apps on the headset itself, rather than PCVR, but you know what they say about things you read on the Internet :wink:

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Cool, thank you both for testing! Ultimately, only Meta knows what this really does lol. So if you did not observe anything, then it probably does nothing when streaming from PC!!

Now here comes the even weirder part: we (VD) had reports that having the option on tanked performance in some cases. That’s another reason why I thought maybe it actually did something. So in the end, it looks like you should just keep it off to avoid any unnecessary risks!

PS: then I have no idea what OP is observing. Hopefully they’ll also experiment.

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Ya, upon further testing with my QPro/Link I did start to notice a slight performance degradation with a few stutters in both msfs2020/2024. Went back and disabled PTW and everything returned to normal again. So, along with msfs motion smoothing I’ll leave then new meta quest v83 experimental PTW disabled for now. Cheers.