一個也許有用的 AutoLISP 程式

cpp 代码

; file: s-arc.lsp

; create a useful lisp of small- arc
; 模擬 人工畫圖的時候，使用圓規 或是 分規，
; 取 等長線段 的動作
; -----------------------------------------------

(defun rtod(r1 / )
  ; d1= (r1/pi)*180.0
  (* (/ r1 pi) 180.0)
  ); end of rtod()
; -----------------------------------------------

(defun dtor(d1 / )
  ; r1= (d1/180.0)*pi
  (* (/ d1 180.0) pi)
  ); end of dtor()
; -----------------------------------------------

(defun c:s-arc( / )
  (setq p1 (getpoint "\n Get 1st point: "))
  (setq p2 (getpoint p1 "\n Get 2nd point: "))

  (setq p3 (getpoint "\n Get 3rd point: "))
  (setq p4 (getpoint p3 "\n Get 4th point: "))
  ; -----------------------------------------------

  (setq s1 (distance p1 p2))
  (setq a1 (angle p3 p4))

  (setq a1 (rtod a1))
  (setq a2 (+ a1 8)
    a3 (- a1 8))

  (setq p5 (polar p3 (dtor a2) s1)
    p6 (polar p3 (dtor a3) s1)
    p4 (polar p3 (dtor a1) s1))

  (command "arc" p5 p4 p6)
  (princ)
  ); end of c:s-arc()
; end of file