public Quaternion getPhysicsRotation(Quaternion rot) {
        if (rot == null) {
            rot = new Quaternion();
        }
        gObject.getWorldTransform(tempTrans);
        Converter.convert(tempTrans.getRotation(tempRot), physicsLocation.getRotation());
        return rot.set(physicsLocation.getRotation());
    }
@param rot storage for the result (modified if not null)
@return the physicsLocation
jme3-jbullet/src/main/java/com/jme3/bullet/objects/PhysicsGhostObject.java