CGAL users discussion list

[Andreas Fabri <>]

On 23/08/2010 16:20, Michel Audette wrote:
> Dear CGAL developers and users,
>
> Sorry if this appeared before, but I just rejoined CGAL users, and
> I did not see my message on the list, so this submission may have gone
> through before my membership.
>
> I'd like to incorporate some CGAL functions into my research, but I
> would like to find out more about licensing.
>
> The website says that some classes are LGPL and some are QPL. I don't
> plan on modifying the source code, but use it as is, like a black box.
> Is the user given the choice for each, or are the licences set as one
> or the other on a case-by-case basis?

Hi Michel,

It is on a case by case base, and the package overview page
http://www.cgal.org/Manual/latest/doc_html/cgal_manual/packages.html
gives this kind of information.


> Moreover, I'm interested in the 3D surface mesh, and would like to
> find out more... Does it produce a mesh that is water-tight? Moroever,
> it seems not to produce slivers (triangles with small edges), which
> has important implications for finite elements. Is this shape quality
> based on a parameter of the algorithm, and does this high quality come
> at a price in terms of distance to the underlying boundary?
> Finally, a former student of mine used ellipsoid approximation in the
> past, I believe Approximate_min_ellipsoid_d .
>
> I would be interested in the licences of both of these. Can I use the
> code freely in both of these cases?

Free or not depends mainly what you do with it, and how free your own 
code is when you distribute it.  The QPL is roughly as the GPL
that is when you use CGAL and distribute your code which uses CGAL,
then you must distribute your code also under an open source license.

So you would probably not be allowed to integrate it in VolView,
but you could wrap it so that it has the API of a vtk filter
(with the wrapped code still having the CGAL and not the vtk license).

Best regards,

Andreas Fabri


> Best wishes,
>
> Michel
>
> --
> Michel Audette, Ph.D.
> R&  D Engineer,
> Kitware Inc.,
> Chapel Hill, N.C.