Fehler im Konturfräsen V17 ?

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wega
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Joined: Mon Nov 11, 2013 3:13 pm

Fehler im Konturfräsen V17 ?

Post by wega »

Hallo zusammen,
ich verwende die Version V17 unter Windows 7.

OS: Windows 7
Word size of OS: 32-bit
Word size of FreeCAD: 32-bit
Version: 0.17.9279 (Git)
Build type: Release
Branch: master
Hash: b05826fc3f51aff731a694bc72292b67d71f4578
Python version: 2.7.8
Qt version: 4.8.7
Coin version: 4.0.0a
OCC version: 7.0.0

Im beiliegenden Programm wird beim Konturfräsen die Tasche
bis zum Boden des Grundkörpers gefräst, was aber laut der
Begrenzungskontur nicht sein dürfte.

Liegt dort ein Fehler vor oder sind meine einstellungen falsch?
Fehler-im-Konturfraesen.jpg
Fehler-im-Konturfraesen.jpg (90.04 KiB) Viewed 2019 times
Taschen.FCStd
(25.01 KiB) Downloaded 38 times
Nit Gruß
Werner
herbk
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Re: Fehler im Konturfräsen V17 ?

Post by herbk »

Hi wega,
it's the same if i make the part with part...
In this moment it seams that the resulting path is the same as made with "profile from face"
contour.png
contour.png (68.8 KiB) Viewed 2001 times
@wega: wenn Du das Teil wirklich fräsen willst/musst, dann geht folgender workaround:
Wähle als Basis for die contour nicht Body sondern das pad.
Gruß Herbert
mlampert
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Re: Fehler im Konturfräsen V17 ?

Post by mlampert »

confirmed, this is a bug.
wega
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Re: Fehler im Konturfräsen V17 ?

Post by wega »

Hallo zusammen,

ja Herbert, man kann den Fehler mit Deinem Vorschlag umgehen.
Loesung-offene-Tasche.jpg
Loesung-offene-Tasche.jpg (67.64 KiB) Viewed 1979 times
Taschen.FCStd
(24.39 KiB) Downloaded 35 times
Gruß Werner
Jee-Bee
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Re: Fehler im Konturfräsen V17 ?

Post by Jee-Bee »

wega wrote:Hallo zusammen,

ja Herbert, man kann den Fehler mit Deinem Vorschlag umgehen.

Loesung-offene-Tasche.jpg

Taschen.FCStd

Gruß Werner
However i understand most of german here in this topic i prefer to talk english over here since this is the english part of the forum..
chrisb
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Re: Fehler im Konturfräsen V17 ?

Post by chrisb »

When
Jee-Bee wrote:However i understand most of german here in this topic i prefer to talk english over here since this is the english part of the forum..
The issue occured first in the german forum. When I recommended there to continue the discussion in the path forum I had thought of course to do so in english, but didn't mention it explicitely :roll: .
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mlampert
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Re: Fehler im Konturfräsen V17 ?

Post by mlampert »

Can't file an issue for the language ;) - but I did file one for Contour:
http://www.freecadweb.org/tracker/view.php?id=2861

Interesting problem and a great find. Thanks for reporting!
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sliptonic
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Re: Fehler im Konturfräsen V17 ?

Post by sliptonic »

Added a note. If I ran my git bisect correctly, it looks like it showed up with this commit but I don't understand the details:

commit 6e7c4915a3a11c32b1c82c128b6b6c0d8799c744
Author: wmayer <wmayer@users.sourceforge.net>
Date: Sun Jan 15 16:34:14 2017 +0100

fixes #0002858: Vector2d Equality Incorrect
mlampert
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Re: Fehler im Konturfräsen V17 ?

Post by mlampert »

He's replacing direct float comparison with fuzzy comparison. Previously a 2d vector and bound box had to be exactly identical to be considered the same - now it allows for an error up to DBL_EPSILON.

I guess findShapeOutline() previsously did not return the middle line due to the usual rounding issues. Now that it's "close enough" it also returns that line. From an "outline" perspective I would call it a bug, from a 2d projection perspective it looks correct (it is what I would expect to see on a drawing).
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sliptonic
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Re: Fehler im Konturfräsen V17 ?

Post by sliptonic »

Look at the image I added on the ticket. Besides the extra internal line (which shouldn't be there) theres also a small spurious segment in the top corner. This wreaked havoc with that part contour.
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