Polyline vertices don't show up where they should

[mritzman]

My polylines show up visibly where I'd like them, but the vertices seem to be mirrored about the "Y" axis. If I do a PEDIT to this polyline then edit vertex, the cross-hairs show up far to the left of the polyline.

I am a bit of a loss for how to explain this problem, so I'm attaching a file that shows it:87446

Please take a look. I know it sounds insane, and doesn't make any sense, but if you'll try it you'll see what I'm talking about.

I noticed this issue only because I use a 3rd party piece of software that processes polylines and extracts their vertex points. Half of those points appeared to be corrupted. I suspected this foreign software till I found the odd behavior originating in the drawing itself.

Has anybody seen this? And do you know how to fix it?

Thanks!

[jaberwok]

Your polyline is mirrored so that it's z orientation is -1.
Changing to a front, back or side UCS and mirroring it corrects it.

[mritzman]

That sounds right to me. I should be able to mirror about the "Z" plane to resolve the issue. Unfortunately, I'm having some difficulty following your suggestions. The result isn't what I expected or hoped. Here's what I've tried:

;;;; First change the view
-VIEW Enter an option [?/Delete/Orthographic/Restore/Save/sEttings/Window]:
_front

;;;; Then Mirror top to bottom
Command: MIRROR
Specify first point of mirror line: 0,0
Specify second point of mirror line: 1,0
Erase source objects? [Yes/No] <N>: Y

;;;; Finally switch back to world coordinates
Command: UCS
Current ucs name: *FRONT*
Specify origin of UCS or [Face/NAmed/OBject/Previous/View/World/X/Y/Z/ZAxis] <World>: world
Command: plan
Enter an option [Current ucs/Ucs/World] <Current>: Current

I still have the same problem when I run PEDIT.

[jaberwok]

I picked the endpoints of the visible line in Front view/UCS and the vertices then lined up correctly in Plan view/WCS.

BTW, I use the View toolbar to change view and UCS together.

[mritzman]

Got it. Thanks!