three.js rotate Object3d around Y axis at it center

Question

I have an Object3d in Three.JS that is a group of some Mesh objects.
I want to rotate this group around the Y axis, at it center, that is far from world center (0,0,0).
I just know the Group.rotate.y += deg code, but for each axis direction it always rotate the object around (0,0,0), not my group center!
How can i fix this?

UPDATE:

Read the comments

Answer 1

Have a look at Object3D's rotateOnAxis(axis, angle) function. It should be something like:

//declared once at the top of your code
var axis = new THREE.Vector3(0.5,0.5,0);//tilted a bit on x and y - feel free to plug your different axis here
//in your update/draw function
rad += radIncrement;
object.rotateOnAxis(axis,rad);

HTH