| CGAL 6.1 - CGAL and the Boost Graph Library
    | 
#include <CGAL/boost/graph/Dual.h>
The class template Dual is an adaptor that creates the dual view of a FaceGraph. 
Faces of the original graph correspond to vertices in the Dual and vice versa.
Note that border edges in a Dual have the null_face of the original graph as either source or target. This is unusual and might break other algorithms since edges are always assumed to have non-null vertices as a source and target. It is possible to filter border edges using boost::filtered_graph as shown in example BGL_surface_mesh/surface_mesh_dual.cpp
Property Forwarding
Edge properties of the underlying graph are forwarded directly. For faces and vertices only the face_index and vertex_index properties are forwarded. Accessing other properties will lead to a compilation error. 
| Primal_ | must be a model of FaceGraph | 
FaceGraph | Public Types | |
| typedef Primal_ | Primal | 
| The underlying primal type. | |
| Public Member Functions | |
| Dual (const Primal &primal) | |
| constructs a Dual from a given primal. | |
| const Primal & | primal () const | 
| returns the underlying primal. | |
| Related Functions | |
| (Note that these are not member functions.) | |
| template<typename Primal > | |
| Dual< Primal > | dual (const Primal &primal) | 
| constructs a Dualfrom a givenprimal. | |