CGAL users discussion list

[Pierre Alliez <>]

hi Tim,

If your vertex is an enriched vertex, ie derived from the base vertex, 
you can add a member
variable there, say an index into a color palette.

When you insert a point into the triangulation, you get a Vertex_handle, ie

Vertex_handle v = insert(p);

you can then specify an attribute by calling eg

v->index() = index;

your elimination algorithm will be able to access the index as well.


Tim Keitt a écrit :
> I need to make a triangulation of points where each point has a color.
> When I'm done, I want to extract the triangulation and eliminate edges
> that have the same color on each end. This is my first attempt at
> using CGAL, so I am a little confused about how I can keep track of
> the identity of a vertex (or its properties) once it has been inserted
> into eg a Delaunay object. If I insert points as triples (x, y, color)
> will I then have access to the color when I iterate over edges in the
> triangulation?
>
> I was looking at the example:
>
> http://www.cgal.org/Manual/3.3/examples/Triangulation_2/terrain.cpp
>
> and noticed that the input file "data/terrain.cin" has four columns.
> (It appears you have to download the entire source in order to find
> this out -- a link in the HTML docs would be welcome!) What is the
> fourth column? Is that what I am looking for?
>
> THK
>
>