(defun getmidpoint (object / p1 p2)
   (vla-getboundingbox object 'p1 'p2)
   (setq p1 (vlax-safearray->list p1)
         p2 (vlax-safearray->list p2)
   )
   (mapcar '* '(0.5 0.5 0.5)(mapcar '+ p1 p2))
)