private void CallFindClosestObject(Vector3d orig, Vector3d ray)
        {
            if (invokeFindClosestObject == null)
            {
                invokeFindClosestObject = new FindClosestObjectDelegate(Grids.FindClosestObject);
            }

            invokeFindClosestObject.BeginInvoke(orig, ray, this.CallBack, null);
        }
        private void CallFindClosestObject(Vector3d orig, Vector3d ray)
        {
            if (invokeFindClosestObject == null)
            {
                invokeFindClosestObject = Grids.FindClosestObject;
            }

            invokeFindClosestObject.BeginInvoke(orig, ray, CallBack, null);
        }