CGAL users discussion list

[Philipp Moeller <>]

David Canino 
<>
 writes:

> Good morning,
>
> I am a very beginner user of CGAL. I am trying to construct simple chains
> from a list of 2D/3D points (at least, but of arbitrary dimension,
> possibly). Basically, I am sure that such points are planar, but their
> order  does not necessarily impose a simple chain. My objective is to form
> simple polygons from their list of points. I am able to do this through the
> convex hull in CGAL, but in this way I discard cases where the input
> polygon is not convex. Any idea to do this in CGAL?

You can probably use Alpha Shapes [1][2] to extract your input shape.

There is also the concept of a Characteristic Hull, but AFAIK no code
for that in CGAL.

Footnotes: 
[1]  
http://www.cgal.org/Manual/latest/doc_html/cgal_manual/Alpha_shapes_2/Chapter_main.html
[2]  
http://www.cgal.org/Manual/latest/doc_html/cgal_manual/Alpha_shapes_3/Chapter_main.html