AUTOLISP畫中心線程式

;;畫中心線程式
(defun c:ted4(/ v CEN  os)
      (setvar "cmdecho" 0)
      (setq v (getvar "clayer"))
      (setq OS(getvar "OSMODE"))
      (setvar "osmode" 4)
      (setq r1 r)
      (setq cen (getpoint "選取中心點:"))(terpri)
 (cond ((= CEN nil)(setvar "OSMODE" OS)))
     (prompt "中心線拉出長度<")(princ r)(prompt ">:")(setq r (getdist cen))(terpri)
      (cond ((= r nil)(setq r r1)))
      (cond ((> r 1)
           
            
      (setvar "CLAYER" "中心線")
      (setvar "OSMODE" 0)
      (command "LINE" (list (car CEN) (- (cadr CEN) r))
                      (list (car CEN) (+ (cadr CEN) r)) "")
      (command "LINE" (list (- (car CEN) r) (cadr CEN))
                      (list (+ (car CEN) r) (cadr CEN)) "")
     (setvar "OSMODE" OS)
      (setvar "CLAYER" V)
      (princ)
)))