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#include <CGAL/Simple_cartesian.h>
#include <CGAL/Polyhedron_3.h>
#include <iostream>
template <class Poly>
typename Poly::Halfedge_handle make_cube_3( Poly& P) {
// appends a cube of size [0,1]^3 to the polyhedron P.
CGAL_precondition( P.is_valid());
typedef typename Poly::Point_3 Point;
typedef typename Poly::Halfedge_handle Halfedge_handle;
Halfedge_handle h = P.make_tetrahedron( Point( 1, 0, 0),
Point( 0, 0, 1),
Point( 0, 0, 0),
Point( 0, 1, 0));
Halfedge_handle g = h->next()->opposite()->next(); // Fig. (a)
P.split_edge( h->next());
P.split_edge( g->next());
P.split_edge( g); // Fig. (b)
h->next()->vertex()->point() = Point( 1, 0, 1);
g->next()->vertex()->point() = Point( 0, 1, 1);
g->opposite()->vertex()->point() = Point( 1, 1, 0); // Fig. (c)
Halfedge_handle f = P.split_facet( g->next(),
g->next()->next()->next()); // Fig. (d)
Halfedge_handle e = P.split_edge( f);
e->vertex()->point() = Point( 1, 1, 1); // Fig. (e)
P.split_facet( e, f->next()->next()); // Fig. (f)
CGAL_postcondition( P.is_valid());
return h;
}
typedef CGAL::Simple_cartesian<double> Kernel;
typedef CGAL::Polyhedron_3<Kernel> Polyhedron;
typedef Polyhedron::Halfedge_handle Halfedge_handle;
int main() {
Polyhedron P;
Halfedge_handle h = make_cube_3( P);
return (P.is_tetrahedron(h) ? 1 : 0);
}
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