Can't snap Intersection where two arcs cross in Draft WB

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acp693
Posts: 127
Joined: Wed Dec 15, 2021 7:41 pm

Can't snap Intersection where two arcs cross in Draft WB

Post by acp693 »

Hi, I have the following draft drawing. The next step is to draw an arc with the radius starting where the two arcs at the bottom cross. Snap intersection doesn't do this, the snap intersect symbol appears, but the end of one or the other arc is highlighted with the white dot. Any ideas how to fix this? I've successfully used snap intersection on other lines. Is there a setting I can change?

Code: Select all

OS: Windows 10 (10.0)
Word size of FreeCAD: 64-bit
Version: 0.21.29485 (Git)
Build type: Release
Branch: master
Hash: a236ca843fdd6674afb6d7ed1454fbd3b547f5ea
Python 3.8.13, Qt 5.12.9, Coin 4.0.0, Vtk 9.1.0, OCC 7.5.3
Locale: German/Germany (de_DE)
Installed mods: 
  * BIM 2021.12.0
  * CurvedShapes 1.0.4
  * Curves 0.5.3
  * FeedsAndSpeeds 0.4.0
  * Marz 0.0.26-alpha
  * Silk 1.0.0
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thomas-neemann
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Re: Can't snap Intersection where two arcs cross in Draft WB

Post by thomas-neemann »

acp693 wrote: Wed Aug 10, 2022 7:26 pm ...
your circular arcs don't work here either. if I create new ones, it works.
1.png
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Code: Select all

OS: Ubuntu 20.04.1 LTS (XFCE/xubuntu)
Word size of FreeCAD: 64-bit
Version: 0.21.29997 (Git) AppImage
Build type: Release
Branch: master
Hash: b52967d52ac46eff7c59e74d991f3f5b298944ef
Python 3.10.5, Qt 5.15.4, Coin 4.0.0, Vtk 9.1.0, OCC 7.6.2
Locale: German/Germany (de_DE)
Gruß Dipl.-Ing. (FH) Thomas Neemann

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NewJoker
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Re: Can't snap Intersection where two arcs cross in Draft WB

Post by NewJoker »

thomas-neemann wrote: Wed Aug 10, 2022 7:46 pm your circular arcs don't work here either. if I create new ones, it works.
Could this be because they belong to construction geometry? I tried ungrouping them but it didn't help.
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thomas-neemann
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Re: Can't snap Intersection where two arcs cross in Draft WB

Post by thomas-neemann »

NewJoker wrote: Wed Aug 10, 2022 7:53 pm ...

Could this be because they belong to construction geometry? I tried ungrouping them but it didn't help.
here it also works with newly made construction geometry. I think it's the freecad version
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mfro
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Re: Can't snap Intersection where two arcs cross in Draft WB

Post by mfro »

That's interesting. It appears the Placement of the arcs is damaged somehow.

If you modify the Placement of both arcs once and back to the original value (e.g. set the Placement's Z-Position from 5 to 0 and back on both in the Data tab), the intersection snap works again. I assume regenerating the Placement matrix fixes the issue.

Would be interesting to know how you managed to create that situation initially. Did you do a FreeCAD upgrade lately?
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Markus
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thomas-neemann
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Re: Can't snap Intersection where two arcs cross in Draft WB

Post by thomas-neemann »

with this software combination it works here too

Code: Select all

OS: Ubuntu 20.04.1 LTS (XFCE/xubuntu)
Word size of FreeCAD: 64-bit
Version: 0.20.29177 (Git) AppImage
Build type: Release
Branch: (HEAD detached at 0.20)
Hash: 68e337670e227889217652ddac593c93b5e8dc94
Python 3.9.13, Qt 5.12.9, Coin 4.0.0, Vtk 9.1.0, OCC 7.5.3
Locale: German/Germany (de_DE)
Bildschirmfoto_2022-08-11_08-25-38.png
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Gruß Dipl.-Ing. (FH) Thomas Neemann

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acp693
Posts: 127
Joined: Wed Dec 15, 2021 7:41 pm

Re: Can't snap Intersection where two arcs cross in Draft WB

Post by acp693 »

Thank you all for checking that. Yes, changing the z position of each line and then back again fixes the issue. I also tried with normal line construction and the same problem occurs, so it's not that they're construction lines. If I draw two arcs that have a bigger crossover angle the snap works, but obviously that isn't helpful for my particular drawing case, but maybe helps narrow the problem. I thought I'd installed the 0.20 release version, but looking again it seems to be version 0.21.
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mfro
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Re: Can't snap Intersection where two arcs cross in Draft WB

Post by mfro »

acp693 wrote: Thu Aug 11, 2022 6:38 am... I thought I'd installed the 0.20 release version, but looking again it seems to be version 0.21.
Could it be your last upgrade was in between, i.e. is it possible that you created the arcs in an earlier version and attempted the point snap in the later version?
Cheers,
Markus
acp693
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Joined: Wed Dec 15, 2021 7:41 pm

Re: Can't snap Intersection where two arcs cross in Draft WB

Post by acp693 »

mfro wrote: Thu Aug 11, 2022 6:46 am
acp693 wrote: Thu Aug 11, 2022 6:38 am... I thought I'd installed the 0.20 release version, but looking again it seems to be version 0.21.
Could it be your last upgrade was in between, i.e. is it possible that you created the arcs in an earlier version and attempted the point snap in the later version?
Hi Marcus, no, I just started the drawing yesterday evening. In any case, your discovery gets around the problem.

Thanks again.
Syres
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Re: Can't snap Intersection where two arcs cross in Draft WB

Post by Syres »

Just purely the visual cursor bug with snapping in general was triggered at Git Revision 0.21.29715 on the master branch so any build before that will be OK with regard to that. I've asked Werner to give me some pointers on how to revert the commit in whole or part to fix the regression. Other bugs in the create of the geometry I can't comment on.
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