How to not solve 'Unterbrochene Linien'

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CVH
Premier Member
Posts: 3416
Joined: Wed Sep 27, 2017 4:17 pm

How to not solve 'Unterbrochene Linien'

Post by CVH » Tue May 04, 2021 7:21 am

The topic was moved to the international forum after I replied in English what is common in the main forum.
Using the English language has been prohibited me there in the past.
So I kindly removed my post 33153.
adebar wrote:
Sun May 02, 2021 6:14 pm
Topic 8409
[Solved] Unterbrochene Linien
by adebar » Sun May 02, 2021 7:14 pm
OC has also a tolerance setting in the Application Preferences and it can bridge gaps.
OG will always result in an open form, OC might result in a closed form when geometrically closed.

OG or OC with a larger tolerance will shift your original entities !!
Look very close at what happens.
With a gap, the next startpoint is replaced by the former endpoint.
They are not auto trimmed!
Examples included:
OGOC+Tolerance.dxf
(107.19 KiB) Downloaded 360 times

My advice here is to use OC with bridging gaps, and then only for all line segments.
QCAD will then add minute bridges that are perfectly inline with the main entities.
These get simplified as simplification is a fixed default with OC.

IMHO: OG-OC should auto trim, also for arcs.
That is unless there are good reasons not to.

The best practice in QCAD is to trim them pairwise upfront, all individually ... All one on one.

Regards,
CVH

CVH
Premier Member
Posts: 3416
Joined: Wed Sep 27, 2017 4:17 pm

Update: How to not solve 'Unterbrochene Linien'

Post by CVH » Thu Oct 14, 2021 7:29 am

Andrew,

Thank you for implementing RPolyline.appendShapeTrim() & RPolyline.closeTrim()
Oct 13, 2021: https://github.com/qcad/qcad/commit/d90 ... 35fa998d14

Curious if that would be used to append shapes to polylines (OG, OC, OL) in the near future?
Will there be a trimming prepending method too?

As of now, only line shapes are trimmed.
The polyline rounding method that I am busy with trims all segments pair-wise.
To avoid appending and prepending shapes it acts on vertice/bulge level.

I have some problems with the fact that the endpoint of the last polyline segment is simply moved.
RPolyline.moveEndPoint(ip) aka setting the last of the vertices to the intersection point.
What if that last segment is bulging?

Moving the endpoint but keeping the bulge factor would result in a different arc shape.
Essentially the reason why I didn't use appending/prepending shapes so far.

Regards,
CVH

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andrew
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Posts: 9037
Joined: Fri Mar 30, 2007 6:07 am

Re: How to not solve 'Unterbrochene Linien'

Post by andrew » Thu Oct 14, 2021 9:03 am

This was implemented as part of a custom project / requirements. There are no plans to change existing functionality.

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