How to accurately align the headset movement for a WebXR scene

Questions
1

I’m noticing the delta between actual motion and the perceived motion in webxr is not accurate. Sideways motion is roughly ok, but up and down motion seems off.

For example, when I move my head vertically up and down (either by looking up and down or by bending & standing up so that my head moves closer to the ground) in the Hill Valley Scene (https://playground.babylonjs.com/#TJIGQ1#3) using my Quest 3, the camera in the scene moves a lot shorter distance.

Does the scale of the camera position events from the headset match babylon’s scale(1 unit = 1 meter) for WebXR? Meaning if I move 1 meter in real life, will it result in the camera shifted by 1 meter? If yes, any pointers on how this effect can be fixed?

2

Babylon itself does not have a unit.

GLTF on the other hand is defined as 1m = 1unit :slight_smile:

So in HillValey the artist may have chosen a different scale during the creation process. That said from what I remembered HillValey was pretty close from a meter = a unit cc @RaananW

Also I added a 1 unit diameter sphere there to compare and it looks ok

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3

I can’t seem to reproduce the incorrect behavior. 1 meter is 1 unit, yes. If i lower my headset all the way to the floor it works as expected, i can also lower myself down to see the internal part of the car, if I teleport right next to it.
Can you share a screencast of the behavior on your headset?

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4

This was a problem on our end. This is now fixed

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