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Octonic's avatar
Octonic
Protege
4 years ago
Solved

Hand Tracking Not Working With OpenXR Backend.

Hello, 

I have just upgraded to version 31.0 of the Oculus integration for unity 2020.3.0f1. It looks like hand tracking isn't working with the OpenXR backend. 
It works fine with the legacy plugin though. 

Does anyone else have the same issue? 

  • korinVR's avatar
    korinVR
    4 years ago

    I can confirm hands are not drawn. It seems hand tracking is not fully supported on the OpenXR backend for now. There is a related description in the release note.

     

    https://developer.oculus.com/downloads/package/unity-integration/

    Support for hand-tracking is currently restricted to the baseline OpenXR spec. Therefore, additional hand-tracking features such as collision capsules, hand input metadata, and runtime hand meshes are not yet supported. In addition, there is a known compatibility issue with the thumb trapezium bone (Thumb0) in the OpenXR-based OVRPlugin. We'll announce a fix when available in our release notes.

12 Replies

  • korinVR's avatar
    korinVR
    Expert Protege
    4 years ago

    I can confirm hands are not drawn. It seems hand tracking is not fully supported on the OpenXR backend for now. There is a related description in the release note.

     

    https://developer.oculus.com/downloads/package/unity-integration/

    Support for hand-tracking is currently restricted to the baseline OpenXR spec. Therefore, additional hand-tracking features such as collision capsules, hand input metadata, and runtime hand meshes are not yet supported. In addition, there is a known compatibility issue with the thumb trapezium bone (Thumb0) in the OpenXR-based OVRPlugin. We'll announce a fix when available in our release notes.
  • prvncher's avatar
    prvncher
    Explorer
    4 years ago

    So I'm having the same issue with V31 (SDK + OS), alongside Unity 2019.4.29f1.

    Hands simply aren't detected and none of the hands sample scenes I've tried detect hands properly.
    (Train demo scene or Passtrough hands).

    When I switch back to the legacy backend, these demos properly detect hands, but then no longer support passthrough.

  • drash's avatar
    drash
    Heroic Explorer
    4 years ago

    With the v34 Unity integration, I confirmed that hand-tracking is still not working with the OpenXR backend.  So +1 to waiting on a fix for that!

  • DYosifov's avatar
    DYosifov
    Honored Guest
    4 years ago

    By "it works fine with the legacy plugin" do you mean after building the APK or during the development with Oculus link? I cannot make it work with Oculus Link in Unity editor and the only way it works is by building and deploying to Quest (which slows the development time a lot).

    I am using v34 of Oculus integration, Unity 2020.3.22f1 and Oculus XR Plugin (tested both 1.10.0 and 1.11.0).

    • Octonic's avatar
      Octonic
      Protege
      4 years ago

      No issue with legacy hand tracking in the editor on Oculus link in my 2020.3.20f1 project on v34. 

  • cliv3dev's avatar
    cliv3dev
    Explorer
    4 years ago

    Basic hand tracking works with OpenXR backend and V34 and Unity 2020.3.x.

    But, as stated in the V34 Release note, there is a known bug on Thumb0 bone as you can see in this screenshot of my game Just Hoops:

     

    OpenXR V34 OVRplugin Thumb0 bug

     

    So if this doesn't bother you, you can use hand tracking anyway with OpenXR !

    I asked for an ETA on the bug fix to the support but no answer yet...

     

    Diego

    • Octonic's avatar
      Octonic
      Protege
      4 years ago

      This is interesting. How did you manage to get the hand and bones to show up? 

  • cliv3dev's avatar
    cliv3dev
    Explorer
    4 years ago

    I took the code from [...]\Assets\Oculus\VR\Scripts\Util\OVRSkeleton.cs and recreated my own data structure to handle all the bones updated by OVRPlugin and in this screenshot it's just a debug rendering of lines connected to each bone coming from the handtracking...

    • Octonic's avatar
      Octonic
      Protege
      4 years ago

      Thanks for the reply. How did you get the bones from OVRPlugin? It looks like getskeleton2 is returning false and nothing is being initialized in OVRSkeleton. 

      • cliv3dev's avatar
        cliv3dev
        Explorer
        4 years ago

        First I check handtracking status of each hand with GetHandState(), and when it returns true, I query a skeleton with GetSkeleton2()...

        See the code:

         

         
                OVRPlugin.HandState _handState = new OVRPlugin.HandState();
                //bool queryHandState(Feature f)
                {
                    bool isTracked=false;
                    if (OVRPlugin.GetHandState(OVRPlugin.Step.Render, f==Feature.HandTrackingLeft?OVRPlugin.Hand.HandLeft:OVRPlugin.Hand.HandRight, ref _handState))
                        isTracked = (_handState.Status & OVRPlugin.HandStatus.HandTracked) != 0;
                    if (isTracked)
        {
         if (OVRPlugin.GetSkeleton2(_featureType==Feature.HandTrackingLeft?OVRPlugin.SkeletonType.HandLeft:OVRPlugin.SkeletonType.HandRight, ref _skeleton)) { initBones(); ...}
        }