[Boost-users] [BGL] Quadtree with vertices ?

Hi all, I would like to use a QuadTree class I've already wrote. To build the QDT, I just need index on each object. I have a boost graphwith bundled properties. For each vertice, I have a Rectangle property and for each rectangle, I have a 2D location. What I want to know is how I can "index" my nodes ? Is it possible to do it automatically ? Thanks Olivier