CGAL users discussion list

[Michael Balzer <>]

Hi,

I'm currently working on a similar problem:

Having an Apollonius graph, I'm trying to extract the polygons of the 
dual Apollonius diagram. Therefore, I extract for each site the dual 
edges of the graph edges that are incident to this site. My current 
method is based on ag.draw_dual_edge() for all edges of the graph, which 
causes some problem when combining all edges to the final polygon.

I would also highly appreciate to have access to a data structure that 
(correctly) represents the Apollonius diagram.


Michael




Bernhard Kornberger schrieb:
>  schrieb:
> > Bernhard Kornberger wrote:
> > >  schrieb:
> >
> > > > > Is it true that I have to implement the conversion from
> > > > > the power diagram to a graph of the power diagram by myself
> > > > > or is there already a function that I didn't find?
> > > >
> > > >
> > > > The graph is dual to the triangulation (up to degeneracies), do you 
> > > > need to convert the triangulation to its dual that you would store 
> > > > in addition ?
> > > >
> > > >     Monique
> > >
> > >
> > > Right. I need a function like this:
> > >
> > > Regular_triangulation Tr;
> > > Tr.insert(p1);
> > > Tr.insert(p2);
> > > Tr.insert(p3);
> > > Tr.insert(p4);
> > >
> > > UndirectedGraph g=Tr.dual();
> > >
> > > ..such that I can traverse along the edges of $g afterwards.
> >
> > but you can traverse edges of g by just following adjacency relations 
> > between tetrahedra in Tr, without storing g.
> >     Monique
>
> I need functions like breath-first search on the edges of the
> power diagram and I need to label edges as already visited or
> not. This is complicated to implement (and horrible to debug)
> if the power-diagram is not explicitly given as a graph.
>
> Best
> Bernhard