CGAL users discussion list

[Khuong Vu <>]

Hi guys,

 

I am Khuong, a newbie in CGAL. I'd like to ask you about some details in the CGAL library

 

1. Where can I find the manual reference for X_handle (e.g, Face_handle, Vertex_handle...). For example, in the implementation examples/Segment_Delaunay_graph_2/sdg-voronoi-edges.cpp, the author called function site() SDG2::Vertex_handle, but I couldn't find any reference to SDG2::Vertex_handle.

 

2. I couldn't find the detail about the manual reference of the Segment_Delaunay_graph_2::Edge (and Edge object in general). For example, in the same file above, the author call e.first, e.second....No reference found either!!!

 

3. I'd like to extract the faces with associated edges of the segment voronoi diagram. Could you guy tell me how to proceed? I'm completely lost in the CGAL's manual reference!!!

 

Looking forward to your response. I truly appreciate your help!

 

Khuong

 

----- Original Message -----

From: "Camille Wormser" <>

To: <>

Sent: Monday, October 27, 2008 5:07 PM

Subject: Re: [cgal-discuss] help with CGAL conceptual

> Edges aren't really stored in Triangulation data structure still 
can  
> be
> accessed threw handlers, iterators and 
circulators.
> Still have a question: How do I create/get edge_handler 
from a facet?

Here is what the Triangulation_data_structure_3 manual 
says:

> typedef Triple<Cell_handle, int, 
int>     Edge;
> (c,i,j) is the edge of cell c 
whose vertices indices are i and j.  
> (See Section 
28.1.)
>
> typedef std::pair<Cell_handle, 
int>     Facet;
> (c,i) is the facet of c opposite 
to the vertex of index i. (See  
> Section 28.1.)


In your 
code, you would access the Cell_handle and the index from the  
Facet_iterator facet by doing

Cell_handle c = facet->first;
int 
index = facet->second;

-- 
Camille