Using spatial anchor causes scale to get overruled

[NoTuxNoBux]

Description:

I have a simple a-box with scale set to something that is not the default. If I place anchored on it and call createAnchor as per the documentation, my scale gets set back to a uniform 1.

It appears that tick in the anchored component does:

pose = frame.getPose(this.anchor.anchorSpace, refSpace);
object3D.matrix.elements = pose.transform.matrix;
object3D.matrix.decompose(object3D.position, object3D.rotation, object3D.scale);

This seems to overrule the entire matrix of the object, including the scale. I verified this by placing const oldScale = object3D.scale.clone(); before the code and object3D.scale.copy(oldScale); after to restore it.

• A-Frame Version: 1.6.0
• Platform / Device: Meta Quest 3
• Reproducible Code Snippet or URL: /

[mrxz]

Spatial anchors represent a space, which means the position, rotation and scale are all defined by it. This way anything placed within that space is relative to the anchor. But the anchored component is documented as anchoring the entity it's applied to, so it actually makes sense to retain the scale.

Opened a PR to fix this issue, see #5633

As a workaround you could either introduce one level of nesting, placing your <a-box> inside an <a-entity> that has the anchored component. Or you can use the width, height and depth properties of a-box instead of setting its scale.