The DWG question

[jriegel]

Hi,
it comes mostly down to the same question. Why should an FOSS project implement a proprietary file format?
It souldent! This formats called itself always open. But if you dig deeper, they are mostly not. Or at least a
try to lock their customers in and keep them from using open formats.

Again, I will no one stop if he wants to implement a import/export module for proprietary formats. But
I think they shut stay away from the core modules of FreeCAD. Its the dark side of the power and to many
patents lurking around to kill a project like ours...

Jürgen

[yorik]

I agree totally with that philosophy. I see importing proprietary formats as a kind of bridge, to allow people (myself, for my concern ) to take all their stuff out of a proprietary platform, and absolutely not as a feature that should be supported... In fact, Lars Grobe just said something like that on the cad-linux list, something that is quite true: Formats like dwg are so much made to be difficult to use by non-autodesk people, there is so much change between each version, that you'd continuously waste many hours of precious developper time on it, instead of doing something useful, just to maintain the stuff half-up-to-date. I personally prefer to see the new stuff comitted almost every day by Jürgen and Werner than thinking they are busy decoding some secret format

For who would be interested, I'm at the moment helping a little bit to the libredwg project, and I think it could be of some use for importing basic stuff (a bit like the dxf importer does at the moment). That's basically my idea, import simple things like lines, circles, etc, in order to have an easy way to take info from old drawings when you need. Support for such simple information is already good enough in libredwg, so I think it's usable for that. Of course, don't expect a decent importer, because I can already see many limitations (retrieving more complex autodesk-style stuff like line color, linestyle, etc is problematic, and different between each version) and I won't spend much of my time on that either. But with a bit of luck it'll already help some people around.

I'll post updates about that here, if any...

Yorik

[jriegel]

Hi,
I followed the argumnts on the PoliGNU list and the entry of Richard Stallman about using a GPL3 library, which mean it works only with GPL2 or higher. Unfortunately Coin is V2 without higher. That means for us we can not use GPLV3 components, which is very sad!
Not even Python modules help us, because they will be linked dynamically while loading in the interpreter.

Im not quit sure how to handle that.....

Jürgen

[yorik]

Yes, that's totally depressing, I've rarely seen more stupid thing than that, two open-source apps that can link one to each other for idiot license version number reasons... When people get zealot about open-source, they are almost worse than their close-source buddies.

Anyway. This whole story taught me something, is that you can't help the world if it doesn't want to be helped. I'll do my own stuff in my corner in order to get my old dwg files in FreeCAD (Of course I'll share the receipes here), but I begin to think it's no wonder if dwg format is staying so long time on the "FSF top-priority list"...

[jriegel]

Hi Yorik,
I totally agree. In that light its not a very smart move to set a library under GPLV3! They shoot itself in the foot....
I think you can use LibreDWG in privat, and you can make a python module if you whant and need it. The only thing I cant do is
release it together, if some one load such a module in FreeCAD I cant do anything about it.
I think you can even distribute it, as long you dont load it with e.g. Pivy....

Another thing is that I read carfully the top priority list. And as I understand it, they whant a free and open replacement of DWG
to get ride of this kind of formates. If you see it in a wider perspective, its more or less the urgend need of a free and open
CAD system. So one could argue, we are the top priority project!

Cheers Jürgen