Re: [Boost-users] limiting searches in BGL

From: Douglas Paul Gregor (gregod_at_[hidden])
Date: 2004-06-15 22:14:08

On Tue, 15 Jun 2004, Jason Crosswhite wrote:

> Hello,
>
> I am just starting to use the BGL, and have been beating my head upon a
> problem.  I am needing to find an irregularly bounded set of points in
> three dimensional space.  The points are within a convex hull and the
> graph edges are edges in a delaunay triangulation.  I want to start at a
> node known to be on the hull, and crawl through the inside with either
> depth first or breadth first search.  If you are on the hull, you would
> not allow the search to continue outside the hull.
>
> I thought of doing this with a simple visitor, and color the unwanted
> vertices black.  However, from inside the scope of the visitor, I do not
> believe I can have access to the colors.  Several ugly hacks come to
> mind, but I would like to know if there is an easy way of doing this first?

I suspect you want a filtered_graph. Just give it predicates that filter
out any points outside the hull. The filtered_graph docs are here:

  http://www.boost.org/libs/graph/doc/filtered_graph.html

        Doug