Centering group of InstancedMeshes on the scene

Questions
1

demo: https://codepen.io/cortezsmz/pen/zYRzWGX

I have a group with a bunch of InstancedMeshes that I’m trying to center on the screen.

The thing is, even after I change the position of each the instances, the bounding box of the group doesn’t seen to change.

Snipet I’m using to center:

    const boundingBox = new THREE.Box3().setFromObject(this.group);
    this.group.position.sub(boundingBox.getCenter(new THREE.Vector3()));

This does works, but the bounding box is wrong, thus the “centering” is wrong.

When I try to render the bounding box of the group with the following snipet, it shows as if the instances were not ever moved

    const box = new THREE.BoxHelper(this.group, 0xff0000);
    this.scene.add(box);

chrome_lYp68WLmSo
chrome_lYp68WLmSo877×134 10.5 KB

BoxHelper of each InstancedMesh (apparently in the wrong position):

chrome_YoJnELQJXV
chrome_YoJnELQJXV886×148 11.8 KB

2

found a PR that should fix the issue with the bounding box on InstancedMeshes (InstancedMesh: Add bounding volumes. by Mugen87 · Pull Request #21507 · mrdoob/three.js · GitHub)

in the mean while, any other ideas on how would I center the group on the scene?