用LISP修改LWPOLYLINE的指定的顶点坐标

Free-Lancer

Change a specific coordinate in a LWPOLYLINE in Lisp                                         By Gopinath Taget
  The LWPOLYLINE (or light weight polyline) will typically have multiple coordinates and it is not easy to modify these vertices. What is the easiest way to access specific coordinates in a LWPOLYLINE and modify it?
  The following lisp code demonstrates an easy way. The lisp code snippet increments the Y values of the LWPOLYLINE vertices by 5 units:
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LWPOLYLINE（或者轻多段线 light weight polyline) 通常有多个顶点并且要修改它们不是很容易，有什么方便的方式存取LWPOLYLINE指定的顶点坐标并且修改它？

  下面的LISP代码演示了一个方便的方法，把一个多段线的顶点坐标的Y值增加5个单位。

2. (defun Test (e ed / i vt)
   
3.   (setq i 0)
   
4.   (repeat (length ed)
   
5.     (if  (= (car (nth i ed)) 10) ;_if item is a vertex
   
6.       (progn
   
7.   (setq vt (cdr (nth i ed))) ;_ get vertex values
   
8.   (setq X (car vt)) ;_ get the x value
   
9.   (setq Y (cadr vt)) ;_ get the y value
   
10.   (setq Y (+ 5 Y)) ;_ increment the Y value by 5 units
    
11.   ;; replace the old y value with the new y value
    
12.   (setq vt (subst Y (nth 1 vt) vt))
    
13.   ;; update the entity definition with new vertex information
    
14.   (setq ed (subst (cons 10 vt) (nth i ed) ed))
    
15.   (entmod ed) ;_update the drawing
    
16.       ) ;_progn
    
17.     ) ;_if
    
18.     (setq i (1+ i))
    
19.   ) ;_repeat
    
20. ) ;_Test
    
21. (defun C:MyTest  (/ e ed)
    
22.   (setq  e  (car (entsel))
    
23.   ed (entget e)
    
24.   )
    
25.   (if (= (cdr (assoc 0 ed)) "LWPOLYLINE")
    
26.     (test e ed)
    
27.   ) ;_if
    
28. ) ;_C:MyTest

(defun Test (e ed / i vt)<br />   (setq i 0)<br />   (repeat (length ed)<br />     (if  (= (car (nth i ed)) 10) ;_if item is a vertex<br />       (progn<br />   (setq vt (cdr (nth i ed))) ;_ get vertex values<br />   (setq X (car vt)) ;_ get the x value<br />   (setq Y (cadr vt)) ;_ get the y value<br />   (setq Y (+ 5 Y)) ;_ increment the Y value by 5 units<br />   ;; replace the old y value with the new y value<br />   (setq vt (subst Y (nth 1 vt) vt))<br />   ;; update the entity definition with new vertex information<br />   (setq ed (subst (cons 10 vt) (nth i ed) ed))<br />   (entmod ed) ;_update the drawing<br />       ) ;_progn<br />     ) ;_if<br />     (setq i (1+ i))<br />   ) ;_repeat<br /> ) ;_Test<br /> (defun C:MyTest  (/ e ed)<br />   (setq  e  (car (entsel))<br />   ed (entget e)<br />   )<br />   (if (= (cdr (assoc 0 ed)) "LWPOLYLINE")<br />     (test e ed)<br />   ) ;_if<br /> ) ;_C:MyTest

xshrimp

楼主有空,最好能翻译一下吧..

yoyoho

感谢Free-Lancer 分享程序!

wxytiger

感谢分享，正好用上。