Question [OpenXR] How to check for position/rotation/velocity at time T instead of just "now" ?

I've been learning the OpenXR API in Unity and I can't figure this out.

Khronos documentation on OpenXR states that you can ask the runtime for Pose data with a timestamp.

https://www.khronos.org/registry/OpenXR/specs/1.0/html/xrspec.html#xrLocateSpace

Is this feature available in Unity?

In Unity you can query the controllers for their position, rotation, velocity etc. during runtime, but can you specify at what time you wish to look at?

 

XR positions are updated every frame. Unity uses the XR position update like a VSYNC, and delays running the next frame till it's ready with new data. This guarantees you to have a fresh location every frame.

If you want a previous location for controllers/headset -- you would have to manually record those previous transform position/rotation. The best data structure to use would be a circular buffer the length of the number of frames you want to keep around, as it's non-ram-allocating after initiation: https://en.wikipedia.org/wiki/Circular_buffer

 

I am facing the same problem. Did you find a solution? I asked a similar question here.