matrix.decompose
HTML
<script src="https://rawgithub.com/BabylonJS/Babylon.js/master/babylon.1.8.0.js"></script>
JavaScript
var q = BABYLON.Quaternion.RotationYawPitchRoll(0.78, 0.78, 0.78);
console.log("Euler angles", q.toEulerAngles());
<script src="https://rawgithub.com/BabylonJS/Babylon.js/master/babylon.1.8.0.js"></script>
var q = BABYLON.Quaternion.RotationYawPitchRoll(0.78, 0.78, 0.78);
console.log("Euler angles", q.toEulerAngles());