CGAL users discussion list

["Laurent Rineau (GeometryFactory)" <>]

Le mardi 29 septembre 2009 12:15:15, 

 a écrit :
> Good afternoon,
> 
> We use CGAL library and self-learn with CGAL on-line manual and tutorials.
>  We succeeded in putting parts together rather easily but there are another
>  two problems we don’t know how to solve.
> 
> -1-
> Our working mesh is a mesh with nearly 180000 facets but the area we’re
> interested in is a little part of this mesh (1/15). On the little area
>  we’re using polyhedra, nefpolyhedra and boolean operations on
>  nefpolyhedra. What is the right and safer method to work on extracts of a
>  mesh and reinsert them in the entire mesh? From the polyhedron made of our
>  big mesh we succeeded in building another polyhedron made of our little
>  mesh but we didn’t use Cgal primitives. Which primitives are to be used in
>  order to split the polyhedron into two polyhedrons and reinsert the little
>  polyhedron in the big one?

If the Euler operations cannot be used, you can build a polyhedron using the 
incremental builder. Maybe you can "make a hole" in your big polyhedron, and 
fill the hole using incremental builder carefully.

Without more information from your side, I doubt somebody can give you a 
better advice.

-- 
Laurent Rineau, PhD
Release Manager of the CGAL Project
http://www.cgal.org/
R&D Engineer at GeometryFactory
http://www.geometryfactory.com/