CGAL users discussion list

["karine hins-mallet" <>]

Hi,

 

In the Polygon Delaunay Graph demo, there is a Drawing function which draws the Voronoï cells of the diagram. This is the code of the function:

 

  typename T::Finite_edges_iterator eit = sdg.finite_edges_begin();

 

  for (; eit != sdg.finite_edges_end(); ++eit) {

      if ( eit->first->vertex( sdg.cw(eit->second) )->info() !=

       eit->first->vertex( sdg.ccw(eit->second) )->info() ) {

            {sdg.draw_dual_edge(*eit, widget);}

 

In that code, I understand that a test is performed on all the edges of the Delaunay graph, and that if the test succeeds then the dual Voronoï edge is drawn. But what I don’t understand is what is done (or checked) in the “if” test. Can someone explain it to me?

 

 

Thank you so much,

 

 

Karine