Possible Bug In Sketcher WB

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Will_C
Posts: 8
Joined: Wed Jan 01, 2020 1:49 pm

Possible Bug In Sketcher WB

Post by Will_C »

Hi Folks,

it appears to me there is an issue with constraining a line to a parabol in certain cases:

If I try to "fix a Point onto an object" the Points of lines do not match the parabols.
The same happens if I draw the Points of a line directly onto the parabols.

In both cases the constrains are listed in the GUI of the Combo view.

I tried to recreate the error with a new file but couldn't manage.
The attached Freecad file is the original one. In this file any line whose points i try to attache are misaligned.

The Report view gives the following message but I'm not sure if it belongs to my Problem:
"Attacher: linked object ImagePlane001 is unexpected, assuming it has no shape."

The python console gives no error, when i draw the line with the constraints:
App.ActiveDocument.Sketch005.addConstraint(Sketcher.Constraint('PointOnObject',57,2,34))

Maybe I did something wrong? I didn't find any info in the forum regarding issues with these type of constraint.
Unfortunately I'm not a CAD expert.

BR,
Will

OS: Windows 7
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.18.4 (GitTag)
Build type: Release
Branch: releases/FreeCAD-0-18
Hash: 980bf9060e28555fecd9e3462f68ca74007b70f8
Python version: 3.6.6
Qt version: 5.6.2
Coin version: 4.0.0a
OCC version: 7.3.0
Locale: German/Germany (de_DE)
Attachments
sketcher_issue.FCStd
(10.47 KiB) Downloaded 35 times
Unbenannt2.JPG
Unbenannt2.JPG (18.61 KiB) Viewed 530 times
Unbenannt.JPG
Unbenannt.JPG (14.72 KiB) Viewed 530 times
chrisb
Veteran
Posts: 53922
Joined: Tue Mar 17, 2015 9:14 am

Re: Possible Bug In Sketcher WB

Post by chrisb »

What you see is only a display issue. Internally the points are placed with much higher precision on the parabolic curve.
A Sketcher Lecture with in-depth information is available in English, auf Deutsch, en français, en español.
Will_C
Posts: 8
Joined: Wed Jan 01, 2020 1:49 pm

Re: Possible Bug In Sketcher WB

Post by Will_C »

Thanks for the quick Response.

Apreciate it. :)
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