CGAL users discussion list

[Andreas Fabri <>]

Daniel Duque wrote:
> On Tuesday 03 November 2009 14:56:28 Michael Jeulin-L wrote:
> > Even If I tried to do a regularized detection,I still have no Edges...
>
> Have you played with the value of alpha? Very small values should give you 
> back all of the edges. Very large ones should give you the convex hull. It's 
> weird, because you should always get something in between...
>
> Best,
>
> Daniel

Hello,

Very small values give you nothing back as then the alpha shape is
just the input point set. There will be an alpha shape edge, if a circle of
radius sqrt(alpha) can not pass between the two vertices, that is if
the squared distance of the two vertices is smaller than alpha.


andreas fabri