hi all, i'm trying to calculate the boundingbox of a parent mesh, so that i may get a good camera asprect. but failed to get the boundingbox size of the parent. are there any tricks there? pg http://www.babylonjs-playground.com/#QVIDL9   // Our built-in 'sphere' shape. Params: name, subdivs, size, scene var sphere = BABYLON.Mesh.CreateSphere("sphere1", 16, 2, scene); // Move the sphere upward 1/2 its height sphere.position.y = 1; // Our built-in 'ground'