solved How to set mesh.parent=null without losing rotation

[digEmAll]

Hi All,

the issue I'm facing is probably trivial to solve but I couldn't find a solution.

Basically I need to set the parent of a mesh (used as rotation pivot) to null after a rotation, because I need to use that pivot again for another group of meshes.

I tried to use the following approach:

var pos = box.getAbsolutePosition();
var rot = box.rotation;
box.parent = null;
box.setAbsolutePosition(pos);
box.rotation = rot;

but it seem to keep only the position, but not the rotation.

I have created a simple playground to reproduce the problem : https://www.babylonjs-playground.com/#S13YXG#2

As you can see, when the animation is completed the bigger box returns to the original rotation.

Any suggestion ?

Thanks a lot in advance

[aWeirdo]

Hi @digEmAll

As you're using rotationQuaternion, box.rotation won't do anything.

furthermore, you should clone the values instead of referencing them (reference will change as the box.parent is removed)
 

var pos = box.getAbsolutePosition().clone();
var rot = box.parent.rotationQuaternion.clone();

    box.parent = null;
    box.setAbsolutePosition(pos);
    box.rotationQuaternion = rot;

https://www.babylonjs-playground.com/#S13YXG#4

[digEmAll]

Thanks a lot! It was easy after all

[brianzinn]

That code might work in your case, but I think a better way to do it is in one line with mesh.setParent(null):
https://github.com/BabylonJS/Babylon.js/blob/master/src/Mesh/babylon.transformNode.ts#L464
https://www.babylonjs-playground.com/#S13YXG#6

[digEmAll]

Thanks @brianzinn, that's great !