toponaming behavior in TechDraw

Report observations made with the new Toponaming branch.
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gigax
Posts: 42
Joined: Tue Oct 20, 2020 2:37 pm

toponaming behavior in TechDraw

Post by gigax »

Hello All,

thanks for all the great work of FC developers!
I have been using FC for ~3 years, mainly for sheet metal parts, and I have designed almost 300 itemss that are currently in production.

My only big problem with FC has always been the toponaming issue, and how it impacts TechDraw. My typical problem is that whenever I need to apply a minor design update to a part, most of the dimensions in TechDraw gets corrupted, so I have to delete them all and restart the dimensioning work from zero.

When you have a panel with ~100 holes and you have to delete and rebuild all dimensions, just because you had to add one additional hole, it's really a problem.

I was hoping to see this fixed with the Link Branch version, but unfortunately it seems to me that the problem persists, so I want to share this example and ask you if you see some solution for it.

In this example (attached file test.FCStd), I made a square sheet metal part with 3 holes:

square3holes.png
square3holes.png (10.33 KiB) Viewed 1328 times

Then I have created a TechDraw page with one view and dimensions:

square3holesviews.png
square3holesviews.png (10.41 KiB) Viewed 1328 times

At this point, if I add one extra hole, I see two possible results, depending on the location of it:

CASE A) The extra hole is added (red in the picture) and the existing dimensions are not modified. Everything worked well.

test-p1.png
test-p1.png (12.57 KiB) Viewed 1328 times

CASE 2) Incorrect, when the extra hole (RED) is added, two of the existing dimensions (BLUE) are corrupted as they "move" from the original references to the new hole. As you can imagine, in a drawing with tenths of dimensions, the level of "damage" is much bigger and all dimensions must be positioned starting from scratch.

test-p2.png
test-p2.png (11.76 KiB) Viewed 1328 times


Any thoughts or suggestions?

Thank you!
Attachments
test.FCStd
(28.9 KiB) Downloaded 39 times
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adrianinsaval
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Joined: Thu Apr 05, 2018 5:15 pm

Re: toponaming behavior in TechDraw

Post by adrianinsaval »

Techdraw needs to be modified to use the toponaming algorithm, IMO that should be the priority once the existing part is merged.
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-alex-
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Joined: Wed Feb 13, 2019 9:42 pm
Location: France

Re: toponaming behavior in TechDraw

Post by -alex- »

gigax wrote: Tue Jul 19, 2022 2:07 pm Any thoughts or suggestions?
Toponaming issue is a huge weakness indeed as TD workbench is concerned.
Unfortunately the topological algo in Link branch dosen't fix this issue because of the HLR algo used by external geometric kernel OCC.
Apply the topoligical algo to HLR seems to be a quite difficult task to code and require reverse enginering.
I'm afraid there is no fix soon on this point.

That's why I've opened a thread few time ago about importing sketches' dimensions directely in TD views.
IMO such workflow would be a fix because it's topologicaly agnostic, very reliable.
More informations here:
https://forum.freecadweb.org/viewtopic.php?f=35&t=44786
Especialy in this post: https://forum.freecadweb.org/viewtopic. ... 10#p548226
Maybe @realthunder can tell us his opinion about this issue and about direct import dimensions feature from sketches to TD views?
Thanks for your kind attention.
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