[Source] Licensing Issue with jgeom library in Xj3D

[Vincent Marchetti]

Notes on jgeom.net library
------------------------------------------------------------
The jgeom-core.jar file is included in the svn repository (in lib directory) in both the trunk and the NPS branch of Xj3D. As far as I can tell with text searching through the java source, this library (jgeom) is only used in the NURBS component files and these classes are not being compiled in the build process, at least for the Xj3D browser -- in other words, I think the jgeom-core.jar file could be deleted from the Xj3D distribution for the trunk and NPS branch.

I have used the jgeom code in my work implementing the parts of the NURBS component, particularly NurbsTrimmedSurface. My changes to the Xj3D code do not work with the jgeom-core.jar file distributed with the NPS branch or the Xj3d trunk. Even if it did, I believe using the jgeom-core jar file would still require licensing the rest of Xj3D as GPL compatible.

Another issue with the net.jgeom library is that the source code is not easy to find -- and under any scenario in which the jar file for this library was distributed with Xj3D, the source code would also have to be available. A source code tar file offered by Sam Gerber at http://www.cs.utah.edu/~sgerber/software/jgeom.tar.gz is incorrectly archived and just contains a directory listing. I have a copy of the source code for jgeom that Christophe Mouton sent me (through a private ftp link) in October 2011.

In summary, distributing the code I've developed for the NURBS component of Xj3D requires replacing or relicensing the jgeom code. The copyright holder (Samuel Gerber) for the jgeom library may give permission to distribute the jgeom library under the less restrictive LGPL license. I can also replace much of the functionality of the jgeom library with j3d classes, but I would still need the trimmed nurbs tesselation algorithm now in the net.jgeom.nurbs.evaluators.TrimSurfaceEvaluator class to be relicensed , or at least get permission to include very similar code in the Xj3D source. As for completely replacing the jgeom library, what I need is code to "generate a mesh  for a trimmed nurbs surface" implemented in java. This is a standard task for geometry kernel software (e.g. Parasolid, OpenCascade, ACIS) but I am not aware of a publically distributed java library that does this. I have it as another project on my to-do list, but it would not be ready, even as a demo, by the time of the Web3d conference in August.

--------------------------------------------------------------

Vincent Marchetti
vmarchetti at ameritech.net

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://web3d.org/mailman/private/source_web3d.org/attachments/20120718/19e8d340/attachment.html>