strange convex pockets with circles

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jCandlish
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strange convex pockets with circles

Post by jCandlish »

I'm trying to understand the Path module. It makes odd toolpaths for convex pockets with circular sections.

Image

Rectangular convex pockets are OK

Image

It there a beginners guide to debugging modules?
danielfalck
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Re: strange convex pockets with circles

Post by danielfalck »

The images that you posted didn't work- could you try again? I think some folks use third party web sites for hosting there images on the forum.
And yes, the pocket operation needs a lot of help. I keep getting side tracked with paying work lately. Sorry about that. I would like to connect that operation to the libarea python module that we are shipping with this workbench. Right now, it uses an OCC offset method that isn't as robust.

Thanks,
Dan
jmaustpc
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Re: strange convex pockets with circles

Post by jmaustpc »

jCandlish wrote: It makes odd toolpaths for convex pockets with circular
danielfalck wrote:The images that you posted didn't work- could you try again? I think some folks use third party web sites for hosting there images on the forum.
I set the post to edit mode, then I could see the URL...I copied it and pasted it into my browser, then Google wanted me to log in for some reason or other....I didn't log in.

as Dan said, just directly add you pictures to the forum post with "add file" and "place in line". Make sure your files are not terribly large, if they are then scale them in Gimp or similar.
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jCandlish
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Re: strange convex pockets with circles

Post by jCandlish »

Damn it Google! You're so seductively naughty!
Screenshot from 2015-11-20 21-05-23.png
Screenshot from 2015-11-20 21-05-23.png (256.74 KiB) Viewed 3416 times
Screenshot from 2015-11-20 21-05-48.png
Screenshot from 2015-11-20 21-05-48.png (211.96 KiB) Viewed 3416 times

Also, I've been looking at http://www.cgal.org/, and http://www.freesteel.co.uk/wpblog/?s=voronoi. http://www.freesteel.co.uk/wpblog/2015/ ... e-voronoi/

The interesting and technically difficult computational geometry codebase is GPL3. There are probably hundreds if not thousands of man-hours to be saved by re-using the existing codes. Would it not be most practical to fork the Path module or re-implement it as GPL3 for this purpose?

I begin to have more time to invest in this project (a CAM module specifically), and so am looking for any pointers on getting started.

How does one build and run FreeCAD from the debugger?

Thanks
jCandlish
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triplus
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Re: strange convex pockets with circles

Post by triplus »

Looks like flipped arcs? ;)

P.S. As for licencing question you would need to create 3rd Party module for FreeCAD and current FreeCAD licence doesn't prevent you doing that.
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jCandlish
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Re: strange convex pockets with circles

Post by jCandlish »

triplus wrote:Looks like flipped arcs? ;)

P.S. As for licencing question you would need to create 3rd Party module for FreeCAD and current FreeCAD licence doesn't prevent you doing that.
I would rather not reverse engineer the Path module from scratch. Yorik van Havre and Dan Falck are the copyright holders. They appear to have used boilerplate LGPLv2 copyright notice throughout?

Would need verification from the copyright holders before forking their code LGPLv2 => GPL3.

Edit: Also the Path module icon artwork is under unclear copyright. It is not listed here ==> http://www.freecadweb.org/wiki/index.php?title=Artwork

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triplus
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Re: strange convex pockets with circles

Post by triplus »

jCandlish wrote:I would rather not reverse engineer the Path module from scratch.
You don't have to as current Path licence doesn’t prevent you to create the fork and add GPLv3 licenced code to it.
Yorik van Havre and Dan Falck are the copyright holders.
I didn't check but yes probably they are.
They appear to have used boilerplate LGPLv2 copyright notice allowing for "either version 2 of the License, or (at your option) any later version".
Yes.
Would need verification from the copyright holders before forking their code LGPLv2 => GPL3.
I am 99% convinced license boilerplate in the files already permits you to do that. For that 100% as it is your project you should make that extra mile yourself. It is your future work licenced under GPLv3 (or part of it) that would need permission to be re-licenced to LGPLv2+ for example if it would be upstreamed to FreeCAD master.
danielfalck
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Re: strange convex pockets with circles

Post by danielfalck »

Since FreeCAD is LGPLv2 as a whole and we aren't going to change that, take a look at how Yorik worked out his DXF plugin in the Draft workbench - using a method of letting the user automatically download the incompatible code and installing it. I thought that was a pretty slick way of dealing with the licensing issue.
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jCandlish
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Re: strange convex pockets with circles

Post by jCandlish »

danielfalck wrote:Since FreeCAD is LGPLv2 as a whole and we aren't going to change that...
I'm just interested in the Path module.

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triplus
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Re: strange convex pockets with circles

Post by triplus »

I guess for the reported flipped arc issue further discussion should be made here as for the licence discussion:

viewtopic.php?f=15&t=12872&p=106243#p106243
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