Topic: Convert HVAC radius elbow to segmented problem..

[danglar]

Hi All!
I need to convert radius elbow to segmented like shown in a picture..
(see attachments)
I find the appropriative routine to convert arc to segmented pline with user defined number of segments
 (see attachments) and now I need a little improvement in this program to draw line or plines from segment vertex’s to center of selected arcs
Can somebody help me to do it?
Any help will be very appreciated

[ronjonp]

Give this a try:

Code - Auto/Visual Lisp: [Select]

1. (defun c:segarc (/ _makepolyline arc arc2 arcs cp d i p1 p2 pst sp x)
2.   ;; RJP 10.13.2016
3.   (defun _makepolyline (layer pts)
4.     (entmakex (apply 'append
5.                      (list (list '(0 . "LWPOLYLINE")
6.                                  '(100 . "AcDbEntity")
7.                                  (cons 8 layer)
8.                                  '(100 . "AcDbPolyline")
9.                                  (cons 90 (length pts))
10.                                  '(43 . 0)
11.                                  '(70 . 1)
12.                            )
13.                            (mapcar '(lambda (x) (list 10 (car x) (cadr x))) pts)
14.                      )
15.               )
16.     )
17.   )
18.   ;; Change 'i' for number of segments
19.   (setq i 8)
20.   (if (setq arcs (ssget ":L" '((0 . "arc"))))
21.     (progn (setq arcs (vl-remove-if 'listp (mapcar 'cadr (ssnamex arcs))))
22.            (while (setq arc (car arcs))
23.              (setq cp (cdr (assoc 10 (entget arc))))
24.              (if (setq arc2 (car (vl-remove-if-not
25.                                    '(lambda (x) (equal cp (cdr (assoc 10 (entget x))) 0.0001))
26.                                    (setq arcs (cdr arcs))
27.                                  )
28.                             )
29.                  )
30.                (progn (setq arcs (vl-remove arc2 arcs))
31.                       (setq sp (vlax-curve-getstartparam arc))
32.                       (setq d (/ (- (vlax-curve-getendparam arc) sp) i))
33.                       (repeat i
34.                         (setq p1 (vlax-curve-getpointatparam arc sp))
35.                         (setq p2 (vlax-curve-getpointatparam arc (setq sp (+ d sp))))
36.                         (_makepolyline
37.                           (cdr (assoc 8 (entget arc)))
38.                           (list p1
39.                                 p2
40.                                 (vlax-curve-getclosestpointto arc2 p2)
41.                                 (vlax-curve-getclosestpointto arc2 p1)
42.                           )
43.                         )
44.                       )
45.                       (entdel arc)
46.                       (entdel arc2)
47.                )
48.              )
49.            )
50.     )
51.   )
52.   (princ)
53. )

[danglar]

Hi  ronjonp.
I'm sorry for not quick answer (it was very long holydays here). I don't know why, but your approach not working for me .. actually it didn’t make nothing. Do you have any explanation about it?

[danglar]

Now I already find the "final" solution of this issue. You can see it here:

https://lispbox.wordpress.com/2016/10/18/convert-radius-elbow-to-segmented-with-user-defined-number-of-segments/

[ronjonp]

Hi  ronjonp.
I'm sorry for not quick answer (it was very long holydays here). I don't know why, but your approach not working for me .. actually it didn’t make nothing. Do you have any explanation about it?

Not sure why it does not work for you .. do your 2 arcs share a common center point?

[danglar]

.. oops.. you are right!
Now I understand ..it was my mistake. Your picture help me a lot to understand a process
Thank you

[ronjonp]

.. oops.. you are right!
Now I understand ..it was my mistake. Your picture help me a lot to understand a process
Thank you

Glad we got it sorted