Topic: Order of Results From 'Intersectwith Method

[ymg]

Am I right with the assumption that (vlax-invoke obj1 'intersectwith obj2 acExtendNone)
always gives  return ordered by distance along curve obj1

So far haven't found any counter examples.

ymg

[Lee Mac]

That may be, but I certainly wouldn't rely on that assumption when a simple vl-sort removes all doubt:

Code - Auto/Visual Lisp: [Select]

1. (defun intersectwith ( obj1 obj2 / lst srt tmp )
2.     (setq tmp (vlax-invoke obj1 'intersectwith obj2 acextendnone))
3.     (repeat (/ (length tmp) 3)
4.         (setq lst (cons (list (car tmp) (cadr tmp) (caddr tmp)) lst)
5.               srt (cons (vlax-curve-getparamatpoint obj1 (car lst)) srt)
6.               tmp (cdddr tmp)
7.         )
8.     )
9.     (mapcar '(lambda ( n ) (nth n lst)) (vl-sort-i srt '<))
10. )

[ymg]

Thanks Lee,

Agree we all know about the saying on assume.

Still would be interesting to know for sure..

ymg

[ymg]

To put it to rest, Self Crossing polylines will give you results that are not ordered.

ymg