progeCAD support, tips and troubleshooting forum. progeCAD works very similar to some versions of AutoCAD. Moderated.

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#1620 by RobinL
Mon Sep 05, 2011 6:11 am
The web page


explains about a PEDIT > Edit vertices > Straighten operation.

That is, select a polyline,
type PEDIT<enter>,
type E<enter>

now straighten is not offered as an option
tried anyway, but
STRAIGHTEN or S is not a recognised command.

This looks like an inconsistency between the documentation and the reality.

Please clarify.
#1621 by RobinL
Tue Sep 06, 2011 3:53 am
I have found an explanation for my message, but does not make mathematical sense.

One confusing problem is that a Polyline in the documentation & menus seems to refer a LwPolyline object (in Entity Properties) and a 3DPolyline in documentation & menus refers to a Polyline (in Entity Properties).

Next, the documentation for each type of object (2D or 3D Polyline) does not explain that for the PEDIT Edit Vertices operation a different set of sub-operations are available depending on whether you have selected a Lwpolyline or a Polyline (Properties). Straighten is an option for Lwpolylines but NOT for Polylines. The sub-operation set for 3D case of Edit Vertices is not explicitly explained. This looks like a problem of the documentation not being revised when a new feature was added.


Mathematically and programming-wise the STRAIGHTEN operation is the same operation that can be performed unambiguously on both polyline types.


#1624 by caddit
Wed Sep 14, 2011 9:29 am

Thank you for your patience. We have reproduced this problem in our lab, and saw exactly the same behaviour in progeCAD 2011. We also verified that even older versions of AutoCAD permit Straighten for 3DPOLY objects. So we had a meeting with the developer to discuss this and a few other topics.

The consensus seems that this is a missing feature (not a bug) - the distinction being a (sub)command that is simply missing, as opposed to something present but working incorrectly (is a bug). So this missing subcommand is slated be added in the next version of progeCAD.

As to your previous concern, "LWPLINE" IS a polyline - but a specifically a PLINETYPE "2" polyline, which is optimised in DXF storage i.e. Light Weight Polyline.
#1625 by RobinL
Fri Sep 16, 2011 11:40 pm
I look forward to a revision that includes the Straighten operation for 3Dploylines.