[求助]如何把兩條SPLINE焊接成一條SPLINE

BDYCAD

我寫了個程序是處理這個問題的. 但不成功, 希望各位大俠可以做的成功. 謝謝  ! ! !

LIHUISHUAN

BDYCAD您好：
看了您的图有点不明白，是不能连接为一条(白线），还是连接后形状变化（绿线）？

BDYCAD

To LIHUISHUAN
    您好! 我的程序目前執行把這兩條spline焊接在綠色的那條了.原因是10的組碼在(曲線控制點)並不在曲線上. 所以使綠色那條是錯誤的. 是我的程序不好造成的. 理想的效果應是只把這兩條曲線原封不動地焊接成一條的呀. 我總找不到正確的做法. 還請你多多指教呀.

meflying

两条曲线的连接处会有问题，你的两个曲线不相连，过度之后会产生变化，即使相连的，两个端点的曲率不同，所以也会有偏差

2. 
   
3. (defun c:test (;|ent1 ent2 |;/ ents1 ents2 lst1 lst2 knot-list controlpoint-list fit-list dxf70
   
4.                dxf71 dxf72 dxf73 dxf74)
   
5.   (setq ent1 (car (entsel)))
   
6.   (setq ent2 (car (entsel)))
   
7.   (setq ents1 (entget ent1))
   
8.   (setq ents2 (entget ent2))
   
9.   (setq knot-list nil)
   
10.   (setq lst1 ents1 lst2 ents2)
    
11.   ;Get all knot point
    
12.   (while (setq lst1 (member (assoc 40 lst1) lst1))
    
13.     (setq knot-list (append knot-list (list (car lst1))))
    
14.     (setq lst1 (cdr lst1))
    
15.   )
    
16.   (while (setq lst2 (member (assoc 40 lst2) lst2))
    
17.     (setq knot-list (append knot-list (list (car lst2))))
    
18.     (setq lst2 (cdr lst2))
    
19.   )
    
20.   (setq lst1 ents1 lst2 ents2)
    
21. 
    
22.   (while (setq lst1 (member (assoc 10 lst1) lst1))
    
23.     (setq controlpoint-list (append controlpoint-list (list (car lst1))))
    
24.     (setq lst1 (cdr lst1))
    
25.   )
    
26.   (while (setq lst2 (member (assoc 10 lst2) lst2))
    
27.     (setq controlpoint-list (append controlpoint-list (list (car lst2))))
    
28.     (setq lst2 (cdr lst2))
    
29.   )
    
30. 
    
31.   (setq lst1 ents1 lst2 ents2)
    
32.   
    
33.   (while (setq lst1 (member (assoc 11 lst1) lst1))
    
34.     (setq fit-list (append fit-list (list (car lst1))))
    
35.     (setq lst1 (cdr lst1))
    
36.   )
    
37.   (while (setq lst2 (member (assoc 11 lst2) lst2))
    
38.     (setq fit-list (append fit-list (list (car lst2))))
    
39.     (setq lst2 (cdr lst2))
    
40.   )
    
41. 
    
42.   (setq dxf70 (cons 70 8))
    
43.   (setq dxf71 (cons 71 (+ (cdr (assoc 71 ents1)) (cdr (assoc 71 ents2)))))
    
44.   (setq dxf72 (cons 72 (+ (cdr (assoc 72 ents1)) (cdr (assoc 72 ents2)))))
    
45.   (setq dxf73 (cons 73 (+ (cdr (assoc 73 ents1)) (cdr (assoc 73 ents2)))))
    
46.   (setq dxf74 (cons 74 (+ (cdr (assoc 74 ents1)) (cdr (assoc 74 ents2)))))
    
47.   
    
48.   (entmake (append
    
49.              (list '(0 . "SPLINE"))
    
50.              (list (cons 100 "AcDbEntity"))
    
51.              (list (cons 100 "AcDbSpline"))
    
52.              (list dxf70)
    
53.              (list dxf71)
    
54.              (list dxf72)
    
55.              (list dxf73)
    
56.              (list dxf74)
    
57.              knot-list
    
58.              controlpoint-list
    
59.              fit-list
    
60.            )
    
61.   )
    
62. )
    

<br /> (defun c:test (;|ent1 ent2 |;/ ents1 ents2 lst1 lst2 knot-list controlpoint-list fit-list dxf70<br />                dxf71 dxf72 dxf73 dxf74)<br />   (setq ent1 (car (entsel)))<br />   (setq ent2 (car (entsel)))<br />   (setq ents1 (entget ent1))<br />   (setq ents2 (entget ent2))<br />   (setq knot-list nil)<br />   (setq lst1 ents1 lst2 ents2)<br />   ;Get all knot point<br />   (while (setq lst1 (member (assoc 40 lst1) lst1))<br />     (setq knot-list (append knot-list (list (car lst1))))<br />     (setq lst1 (cdr lst1))<br />   )<br />   (while (setq lst2 (member (assoc 40 lst2) lst2))<br />     (setq knot-list (append knot-list (list (car lst2))))<br />     (setq lst2 (cdr lst2))<br />   )<br />   (setq lst1 ents1 lst2 ents2)<br /> <br />   (while (setq lst1 (member (assoc 10 lst1) lst1))<br />     (setq controlpoint-list (append controlpoint-list (list (car lst1))))<br />     (setq lst1 (cdr lst1))<br />   )<br />   (while (setq lst2 (member (assoc 10 lst2) lst2))<br />     (setq controlpoint-list (append controlpoint-list (list (car lst2))))<br />     (setq lst2 (cdr lst2))<br />   )<br /> <br />   (setq lst1 ents1 lst2 ents2)<br />   <br />   (while (setq lst1 (member (assoc 11 lst1) lst1))<br />     (setq fit-list (append fit-list (list (car lst1))))<br />     (setq lst1 (cdr lst1))<br />   )<br />   (while (setq lst2 (member (assoc 11 lst2) lst2))<br />     (setq fit-list (append fit-list (list (car lst2))))<br />     (setq lst2 (cdr lst2))<br />   )<br /> <br />   (setq dxf70 (cons 70 8))<br />   (setq dxf71 (cons 71 (+ (cdr (assoc 71 ents1)) (cdr (assoc 71 ents2)))))<br />   (setq dxf72 (cons 72 (+ (cdr (assoc 72 ents1)) (cdr (assoc 72 ents2)))))<br />   (setq dxf73 (cons 73 (+ (cdr (assoc 73 ents1)) (cdr (assoc 73 ents2)))))<br />   (setq dxf74 (cons 74 (+ (cdr (assoc 74 ents1)) (cdr (assoc 74 ents2)))))<br />   <br />   (entmake (append<br />              (list '(0 . "SPLINE"))<br />              (list (cons 100 "AcDbEntity"))<br />              (list (cons 100 "AcDbSpline"))<br />              (list dxf70)<br />              (list dxf71)<br />              (list dxf72)<br />              (list dxf73)<br />              (list dxf74)<br />              knot-list<br />              controlpoint-list<br />              fit-list<br />            )<br />   )<br /> )<br />

LIHUISHUAN

to bdycad:
您好！您讲的合成一条比较难办，我只能给您提供一条可能的思路：
按照样条曲线的数学定义，即控制点与曲线的函数关系入手。通过两曲线已知的控制点坐标，
用数学方法拟合成一条，这个方法非常笨拙，如有更好的思路最好不用这个方法！
关于样条曲线的定义，相关书籍上都有介绍。

BDYCAD

謝謝 Ｍｅｆｌｙｉｎｇ大俠和　Ｌｉｈｕｉｓｈｕａｎ大俠的熱情幫助，　
      目前Ｍｅｆｌｙｉｎｇ的程序存在點問題，　我經過這三天的測試和更改，以經改好了．再在點出來供大家參考．我試過很好用．但如這個圖的曲線就不能用了，還得要ｍｅｆｌｙｉｎｇ兄給我指正這個程序，　謝謝! ! !

BDYCAD

不知為什麼當要焊接的曲線被打斷後DXF組碼就缺少了11的組碼? 使這個程序運行失敗, 還請各位大俠指點指點呀. 謝謝了.