OpenXR Boundaries

Unity Engine
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I switched to OpenXR and was initially extremely positively surprised. Everything seems to work out of the box. EXCEPT. The boundaries through TryGetBoundaryPoints. That is a big mess. Every provider and combination seems to provide different but also always incorrect results. When switching back to legacy non-OpenXR and OVR Manager everything is fine again (OpenXR 1.2.8, Unity 2021.1.23, Rift, Quest, Vive).

Some providers return a rectangle, some the full boundary with hundreds of points. Sometimes there is simply nothing returned. And if there is a rectangle, it has nothing to do with the real boundary and is way too big and unaligned.

What I am looking for is a reliable way to get the biggest rectangle available in the play space, like xrGetReferenceSpaceBoundsRect of the OpenXR spec describes. How can I get access to this data in a reliable way?

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TryGetBoundaryPoints always returns same 4 positions
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I have made a note to look into exposing this information and investigating TryGetBoundaryPoints in OpenXR, however that may take a bit of time on our end. If you dont want to wait you could write your own OpenXR Feature that returns the value of xrGetReferenceSpaceBoundsRect yourself too.

This isnt a simple task but may be a work around for now if you can get it working. The intercept sample included with OpenXR may help you as well.

https://docs.unity3d.com/Packages/com.unity.xr.openxr@1.2/manual/features.html

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We investigated TryGetBoundaryPoints in OpenXR. Here are some notes:

  1. in OpenXR, we actually return bound rect values - width & height obtained from xrGetReferenceSpaceBoundsRect via TryGetBoundaryPoints if you have guardian/ boundary setup in headset and boundary data is supported by runtime. We formatted it into a List of size 4, representing the 4 points of play space rectangle. (some platforms require to have a roomscale guardian setup)

  2. There is a known issue when using Quest with Link, the result is not correct. We already reached out to Oculus about this issue, but we don’t have an ETA when it will be fixed.

One more thing to clarify, for legacy non-openXR Oculus provider, TryGetBoundaryPoints will return a list of detailed boundary points (may including hundreds of points).

Please let me know if you have any other questions.

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I just ran into this issue in Unity 2021.3.4. I try to use Unity’s API’s for everything, but TryGetBoundaryPoints() does not work with Oculus when using the OpenXR backend. It would be great if I could do this using Unity’s API.

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Also having this issue with Oculus over link in Unity 2021.3.25. Would prefer built-in OpenXR over using Oculus SDK as this has been a pain to program around when we want to be HMD agnostic. Any updates appreciated! Also noteworthy: Oculus (when using OpenXR) is not calling OnBoundaryChanged() on recenter events.

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Hello re this - we really need more detailed boundary information than that. For example if the user is in a roughly L-Shaped room - then the boundary rectangle it returns could well be in the other leg of the L-shaped room - i.e. around the corner from where they are actually standing and actually intending to do the VR experience.- which means we have no way at all of getting useful boundary info -
Would it be possible to also expose the full boundary geometry?