localToWorld uses matrix from the previous frame

Description of the problem

It seems that Object3D.prototype.localToWorld (and all other matrix-related stuff) works with the matrix that is not up to dated. This can be easily checked by the following code:

const object = new three.Mesh(
    new three.BoxGeometry(1, 1, 1),
    new three.MeshBasicMaterial,
);

// expected : 0, 0, 0
// actual   : 0, 0, 0
console.log(object.localToWorld(new three.Vector3(0 ,0, 0)));

object.position.set(1, 2, 3);

// expected : 1, 2, 3
// actual   : 0, 0, 0
console.log(object.localToWorld(new three.Vector3(0 ,0, 0)));

object.updateWorldMatrix(true, false);

// expected : 1, 2, 3
// actual   : 1, 2, 3
console.log(object.localToWorld(new three.Vector3(0 ,0, 0)));

The only way to fix this is to use updateWorldMatrix (or render the scene) to force matrix update. In my case this causes a camera to lag behind the object which it is tracking. That was definitely not what I was expect to see, so I think this should be fixed.

[Mugen87]

Three complaints out of how many millions of users?

You should not do the mistake to underestimate the current performance limitations of the engine’s world matrix computations. Other engines like BabylonJS handle this topic way better. Even if there are no new complains, the way three.js updates its world matrices needs to be revisited.

[Mugen87]

Yes, that sounds good. We need a test case for validation anyway!