CGAL users discussion list

[Francesc Vila <>]

El 21/01/2011 17:03, sara123 escribió:
> How can I have the result of union calculating of some simple polygons in
> CGAL::Polygon_2<Kernel>  data type?
> My goal is calculating the area of the polygon that is the union result of
> some simple polygons.
> Now I have this result in these data types:
>
> 1-CGAL::Polygon_with_holes_2<Kernel>
>                 or
> 2-CGAL::Polygon_set_2<Kernel>
Well, maybe there is a better way, but a polygon with holes has a 
CGAL::Polygon_2 (which is the outer boundary) and several 
CGAL::Polygon_2 which are the holes.

CGAL::Polygon_2 has an area member function, which returns the signed 
area, so you could calculate the area of the outer boundary and 
substract the area of each hole.

Regards,

Francesc Vila