Marble Tower Demo doesn't work anymore

The old great demo at
No physics and strange freeze when clicking and rotating the model.
I suppose the reason is somehow connected with Ammo.js

Hey there, you are using a revision of the playground. If you use the original revision, it works (at least for me).

The difference seems to be in these four lines, which are not present at that place (~line 144) in the original revision - and deleting them in your revision has the tower working again:

    var rootNodes = scene.rootNodes.slice();
    var root = new BABYLON.TransformNode("Tower", scene);
    for (var node of rootNodes) {
        node.parent = root;


I am too new to have a clue what these lines are supposed to do, but apparently something connected to them stops the simulation from working :slight_smile:

The working original revision:

1 Like

Thank you for your attention.
It helped me to understand that there was also skybox in this demo.
And I found the link which I used at my page -

It works at PG and works at my page; but it doesn’t work at my page if there is Babylon Viewer instance too.
I’ll try to recreate conditions and see if it could be a bug or my own mistake.

UPD. The bug at my page was due to very special combination of Babylon.js, and Viewer with no model provided. Now I am happy to say that it is not a bug :slight_smile: