CGAL users discussion list

["Laurent Rineau (GeometryFactory)" <>]

On Wednesday 15 April 2009 22:28:56 skific wrote:
> Hi,
> I'm using CGAL::Delaunay_triangulation_2<Traits,Tds> to generate
> triangulation mesh.
> I'd like to remove triangle faces based on predefined criteria, say I'd
> like to remove triangles that are too "narrow" - one of three angles is say
> smaller than 10°.
> Is there a way to remove  triangles (their faces) from the mesh, but
> without removing vertices?

You can add vertices. One way to destroy a triangle in a Delaunay 
triangulation is to insert whatever point into the interior of its 
circumcircle (because the new point breaks the "empty circles" rule). 
Delaunay 
refinement algorithms use that trick. In CGAL, the component "2D Conforming 
Triangulations and Meshes" does that:

http://www.cgal.org/Manual/3.4/doc_html/cgal_manual/Mesh_2/Chapter_main.html

You should have a look at its user manual, to see if that component fits your 
needs.

-- 
Laurent Rineau, PhD
Engineer at GeometryFactory
http://www.geometryfactory.com/