[求助]多段线中圆弧圆心如何获得？

ZZXXQQ

superxzg 发表于 2007-2-5 16:35
zzxxqq，你真是我的偶像啊，真厉害！这都能想到！能不能给我介绍一下“p”的含义？我看书上是说“对应Autoc ...

;凸度计算弧心

2. (defun c:tt ()
   
3. (setq pclst (list))
   
4. (if (and (setq s1 (entsel "\n选择多段线: "))
   
5.           (setq ent (entget(car s1)))
   
6.           (= (cdr(assoc 0 ent)) "LWPOLYLINE")) (progn
   
7.   (setq J 0 N (cdr (assoc 90 ent)) CL (rem (cdr (assoc 70 ent)) 2) K 1)
   
8.   (while (/= (car (nth J ent)) 10) (setq J (1+ J)))
   
9.   (setq P1 (cdr (nth J ent)) PS P1)
   
10.   (repeat (1- N)
    
11.    (setq P2 (cdr (nth (+ J (* K 4)) ent)) BULGE (cdr (nth (+ J (* K 4) -1) ent)))
    
12.    (if (> (abs BULGE) 0.0)
    
13.     (setq LL (* (distance P1 P2) 0.5) ANG (angle P1 P2)
    
14.           PC (polar (polar P1 ANG LL) (- ANG AL1) (* (+ BULGE (if (> BULGE 0) -1 1)) LL))
    
15.           pclst (cons PC pclst))
    
16.    )
    
17.    (setq P1 P2)
    
18.   )
    
19.   (setq BULGE (cdr (nth (+ J (* K 4) -1) ent)))
    
20.   (if (= CL 1)
    
21.    (if (> (abs BULGE) 0.0)
    
22.     (setq LL (* (distance P1 PS) 0.5) ANG (angle P1 PS)
    
23.          PC (polar (polar P1 ANG LL) (- ANG AL1) (* (+ BULGE (if (> BULGE 0) -1 1)) LL))
    
24.          pclst (cons PC pclst))
    
25.    )
    
26.   )
    
27. ))
    
28. pclst
    
29. )
    

(defun c:tt ()<br /> (setq pclst (list))<br /> (if (and (setq s1 (entsel "\n选择多段线: "))<br />           (setq ent (entget(car s1)))<br />           (= (cdr(assoc 0 ent)) "LWPOLYLINE")) (progn<br />   (setq J 0 N (cdr (assoc 90 ent)) CL (rem (cdr (assoc 70 ent)) 2) K 1)<br />   (while (/= (car (nth J ent)) 10) (setq J (1+ J)))<br />   (setq P1 (cdr (nth J ent)) PS P1)<br />   (repeat (1- N)<br />    (setq P2 (cdr (nth (+ J (* K 4)) ent)) BULGE (cdr (nth (+ J (* K 4) -1) ent)))<br />    (if (> (abs BULGE) 0.0)<br />     (setq LL (* (distance P1 P2) 0.5) ANG (angle P1 P2)<br />           PC (polar (polar P1 ANG LL) (- ANG AL1) (* (+ BULGE (if (> BULGE 0) -1 1)) LL))<br />           pclst (cons PC pclst))<br />    )<br />    (setq P1 P2)<br />   )<br />   (setq BULGE (cdr (nth (+ J (* K 4) -1) ent)))<br />   (if (= CL 1)<br />    (if (> (abs BULGE) 0.0)<br />     (setq LL (* (distance P1 PS) 0.5) ANG (angle P1 PS)<br />          PC (polar (polar P1 ANG LL) (- ANG AL1) (* (+ BULGE (if (> BULGE 0) -1 1)) LL))<br />          pclst (cons PC pclst))<br />    )<br />   )<br /> ))<br /> pclst<br /> )<br />

czcxxx

谢谢分享！！！！！！！！！！！！！