vlide: Membuat gambar potongan plafond

Berikut ini adalah program autolisp untuk membuat gambar potongan plafond :

(defun c:plf (/ pt1 pt2 pt3 pt4 pt5 pt6 pt7 pt8 pt9 pt10 pt1a pt1b pt1c pt1d pt1e pt1f pt2a pt2b pt2c pt2d pt2e pt2f jr)
   (command "undo" "be")
   (setvar "cmdecho" 0)
   (initget 1)
   (setq pt1 (getpoint "\nStart Point: "))
   (initget 1)
   (setq pt2 (getpoint pt1 "\nEnd Point: "))
   (setq jr (distance pt1 pt2))
   (setq ang (angle pt1 pt2))
   (setq pt3 (polar pt1 (+ (/ pi 2) ang) 10))
   (setq pt4 (polar pt3 ang jr))
   (setq pt5 (polar pt3 (+ (/ pi 2) ang) 40))
   (setq pt6 (polar pt5 ang jr))
   (setq pt7 (polar pt3 ang 40))
   (setq pt8 (polar pt4 (+ pi ang) 40))
   (setq pt9 (polar pt5 ang 40))
   (setq pt10 (polar pt6 (+ pi ang) 40))

   (setq pt1a (polar pt1 ang 10))
   (setq pt1b (polar pt3 ang 10))
   (setq pt1c (polar pt1 ang 1))
   (setq pt1d (polar pt1c (+ (/ pi 2) ang) 9))
   (setq pt1e (polar pt1d ang 8))
   (setq pt1f (polar pt1c ang 8))

   (setq pt2a (polar pt2 (+ pi ang) 10))
   (setq pt2b (polar pt4 (+ pi ang) 10))
   (setq pt2c (polar pt2 (+ pi ang) 1))
   (setq pt2d (polar pt2c (+ (/ pi 2) ang) 9))
   (setq pt2e (polar pt2d (+ pi ang) 8))
   (setq pt2f (polar pt2c (+ pi ang) 8))

   (setq lama (getvar "osmode"))
   (setvar "osmode" 0)
   (setvar "clayer" "ceiling")
   (command "line" pt1a pt2a "")
   (setvar "clayer" "fin")
   (command "line" pt3 pt9 pt10 pt4 "")
   (command "line" pt5 pt7 pt8 pt6 "")
   (setvar "clayer" "steel")
   (command "pline" pt3 pt7 pt9 pt5 "c")
   (command "pline" pt4 pt8 pt10 pt6 "c")
   (command "pline" pt1 pt3 pt1b pt1a pt1f pt1e pt1d pt1c "c")
   (command "pline" pt2 pt4 pt2b pt2a pt2f pt2e pt2d pt2c "c")
   (setvar "clayer" "0")
   (setvar "osmode" lama)
)

Contoh hasil pembuatannya :