CGAL users discussion list

["Sebastien Loriot (GeometryFactory)" <>]

As an alternative solution to Efi's, you can compute the boundary of the
union of the disks efficiently using the 2D Alpha shape package.

Then the area of the union of disk is given by a formula that involves
the signed arc length and angle between tangents at intersection point.
I don't remember precisely the formula but I guess you can easily find
it online.

For the union of disks, if you are interested we can send you a link to
some code that is computing the union of the disks that we wrote some
time ago (yet another piece of code that should be integrated into
CGAL).

Best regards,

Sebastien.

On 2/26/20 3:09 PM, Yann GAVET wrote:
> Hi all,
>
> Sorry to bother with this probably naive question. I want to compute the 
> area of the union of a set of disks. I found the example of "2D 
> regularized boolean set-operations", at the end of this page:
>
> https://doc.cgal.org/latest/Boolean_set_operations_2/index.html.
>
> Is there a way to modify this example in order to compute the area of 
> the union, which is (if I am right) a general polygon with holes.
>
>
> thank you for your time.
>
> regards