CGAL users discussion list

[Stefan Salewski <>]

On Mon, 2013-09-30 at 10:17 +0200, Mariette Yvinec wrote:
> The solution of Michael won't  work if the polygonal regions
> you are tracking are not simply connected and convex.
> 
> Here is a more general  solution.
> Starting from the examples that mark the triangular faces inside the polgon
> it is easy to get the edges inside the polygons:
> these are the edges adjacent to two marked polygons.
> 

Thanks for that hint.

Yes, I understand (now) that it may fail for non convex polygons. I
guess that I will have only convex ones.

Currently I can not fully understand your suggestion

>these are the edges adjacent to two marked polygons

For my case I may have only one polygon (or more than one but with large
distance to each other). I want to find the inner edges, as stated in my
first posting. I can not see how that may work for non convex polygons
now -- have to do some thinking...

Best regards

Stefan Salewski