change start and end point of polyline and change mid points relevently

[Dayananda]

I hve alisp program to mark chainages of polyline.

But always  the start point and end point is same. I want to change direction of cranages as showen in  the picture.  Can some one help me to change polyline properties to full fill this task.

[Stefan BMR]

PEDIT command has the option to revert the polyline. However, you have to run the lisp once, then, if require revert, you have to UNDO the lisp, revert the polyline, then run the lisp again.

IMO, the chainage lisp should decide the starting point based on the selection point.

[Dayananda]

THNKS IT WORKS

[DavidP]

There is also the  "reverse" command.

To work with lines that require specific direction  I typical temporally change the object line type this custom linetype -->--->---> ... and once I'm done with task I re-set back to by-layer.

 

arrow.lin

[BIGAL]

This will reverse a pline if required. I would also look at Lee-mac "Text readable.lsp" as some of your text is up is up side down.

 

(setq ent (entsel "\npick a line near end "))
(setq obj (vlax-ename->vla-object (car ent)))
(setq startpt (vlax-curve-getstartPoint obj))
(setq endpt (vlax-curve-getEndPoint obj))
(setq pt1 (cadr ent))
(setq d1 (distance pt1 startpt))
(setq d2 (distance pt1 endpt))
(if (< d1 d2)
  (command "pedit" (car ent) "R" "")
)

 

Edited April 22 by BIGAL

[X11start]

To change the origin and/or direction of a polyline, I recommend this excellent Lisp of Giampaolo Cattaneo.CHVERT.LSP