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[Gilles <>]

Hello CGALer,

(Sorry) I'm still a newbee in CGAL and I have this following problem :

Trying to build a simple prism (with a triangle base) and I get this error 
when
I try to build a facet sharing points with another one :

lookup_halfedge(): input error: facet 2 shares a halfedge from vertex 0 to
vertex 1 with facet 0.

My code is :

...

B.begin_surface(6,3,0);
                //upper vertices
                B.add_vertex( Point_3(-1,0,0));
                B.add_vertex( Point_3(1,0,0));
                B.add_vertex( Point_3(0,1,0));

                //lower vertices
                B.add_vertex( Point_3(-1,0,-1));
                B.add_vertex( Point_3(1,0,-1));
                B.add_vertex( Point_3(0,1,-1));

                //upper-facet
                B.begin_facet();
                    B.add_vertex_to_facet(0);
                    B.add_vertex_to_facet(1);
                    B.add_vertex_to_facet(2);
                B.end_facet();

                //bottom-facet
                B.begin_facet();
                    B.add_vertex_to_facet(3);
                    B.add_vertex_to_facet(4);
                    B.add_vertex_to_facet(5);
                B.end_facet();

                // side-facet 1 of 3  (doing this make problem)
                B.begin_facet();
                    B.add_vertex_to_facet(0);
                    B.add_vertex_to_facet(1);
                    B.add_vertex_to_facet(4);
                    B.add_vertex_to_facet(3);
                B.end_facet();
B.end_surface();
...

What's wrong ?


Gilles