It didn't quite work as expected for me. I altered the code a bit (converted the dot product to an angle using Math.acos) This works great for me.   http://www.babylonjs-playground.com/#1RWE59#13 // You have to create a function called createScene. This function must return a BABYLON.Scene object// You can reference the following variables: scene, canvas// You must at least define a camera// More info here: https://github.com/BabylonJS/Babylon.js/wiki/The-Playgroundvar createScene = function ()