CGAL users discussion list

["Jingyi Jin" <>]

I made a mistake in the last email, it should be finding incident cells of the vertex, not facets, and then compute their dual...

Angelo, the following highlighted piece of code shows how to use the incident_cells method:

 

#include <iterator>

...

for each vit of Finite_vertices {

    vector<Cell_handle> temp_c;

    temp_c.reserve(64);

    incident_cells(vh, std::back_inserter(temp_c));

 

    for each cit of temp_c {

        Point p = T1::dual(*cit);

        ... ...

    }

}

 

best,

Jingyi

 

On 5/29/07, Tardugno, Angelo <> wrote:

The poles are defined as the furthest voronoi vertices, so they're a subset of the voronoi vertices. My problem is how to implement the idea you've just exposed. I've found this on CGAL-manual

 

template

<class OutputIterator >

OutputIterator t.incident cells( Vertex handle v, OutputIterator cells)

Copies the

Cell handles of all cells incident to v to the output iterator

cells

. If t. dimension() < 3, then do nothing. Returns the resulting output

iterator.

 

but I have no idea of what an OutputIterator is. At the moment I'm thinking of doing an iteration on the finite vertices of the triangulation (using a Finite Vertices Iterator) and for each of the vertices find the incident cells and calculate their dual (these are the Voronoi vertices corresponding to the sample I'm considering). Among these vertices I then have to find the two furthest. Anyway, at the moment I'm stuck at the point of finding the incident cells since I have no idea of how using the incident_cells method.

Anyone can help me?!

Thanks

 

Angelo Tardugno

Precondition

: v 6= Vertex handle(), t.is vertex(v) .

---

From: Jingyi Jin [mailto:]
Sent: 29 May 2007 16:35
To:
Subject: Re: [cgal-discuss] How to excract poles

 

Hi Angelo,

 

Is it true that the poles are always Voronoi vertices? If so, you can get all incident Delaunay facets to a vertex v, compute the dual of those facets, which are vertices of Voronoi cell of v. Loop over those vertices, and the furthermost one is the pole.

 

This is my thought, I am not sure if I interpreted things correctly.

 

Jingyi

 

On 5/29/07, Tardugno, Angelo <> wrote:

Hi CGAL experts,

 

I have to extract the poles of each Voronoi cell of a cloud of 3D point. Can anybody can give me an hint of how this can be done with CGAL? I thought that I have to consider each Delaunay vertex and then, somehow, bulid its correspondent Voronoi cell and then consider the farthest vertices of this cell. Still I don't know where to begin. Thank You for your help

 

Angelo Tardugno