(defun c:tt (/ ss n ent para p1 p2 p3)
(if (setq ss (ssget '((0 . "LWPOLYLINE"))))
(repeat (setq n (sslength ss))
(setq ent (ssname ss (setq n (1- n)))
para (vlax-curve-getEndParam ent)
p1 (vlax-curve-getPointAtParam ent 0)
p2 (vlax-curve-getPointAtParam ent (fix (* para 0.33)))
p3 (vlax-curve-getPointAtParam ent (fix (* para 0.66)))
)
(3PCircle p1 p2 p3)
(entdel ent)
)
)
(princ)
)
3点画圆自己算会快一些