void transform_big(Nef_polyhedron& N,int n, int s) {
Vertex_const_iterator vi(N.vertices_begin());
x_min = vi->point().hx()/vi->point().hw();
x_max = vi->point().hx()/vi->point().hw();
y_min = vi->point().hy()/vi->point().hw();
y_max = vi->point().hy()/vi->point().hw();
z_min = vi->point().hz()/vi->point().hw();
z_max = vi->point().hz()/vi->point().hw();
for(;vi != N.vertices_end();++vi) {
if(vi->point().hx()/vi->point().hw() < x_min)
x_min = vi->point().hx()/vi->point().hw();
if(vi->point().hx()/vi->point().hw() > x_max)
x_max = vi->point().hx()/vi->point().hw();
if(vi->point().hy()/vi->point().hw() < y_min)
y_min = vi->point().hy()/vi->point().hw();
if(vi->point().hy()/vi->point().hw() > y_max)
y_max = vi->point().hy()/vi->point().hw();
if(vi->point().hz()/vi->point().hw() < z_min)
z_min = vi->point().hz()/vi->point().hw();
if(vi->point().hz()/vi->point().hw() > z_max)
z_max = vi->point().hz()/vi->point().hw();
}
// x_min-=(x_min<=0?0:1);
// y_min-=(y_min<=0?0:1);
// z_max+=(z_max<=0?1:0);
N.transform(Aff_transformation_3(CGAL::TRANSLATION, Vector_3(-x_min,-y_min,-z_max)));
N.transform(Aff_transformation_3(CGAL::SCALING, n*s+2,x_max-x_min));
N.transform(Aff_transformation_3(CGAL::TRANSLATION, Vector_3(0,0,s/2)));
}
void transform_form(const Nef_polyhedron& N, Nef_polyhedron& F) {
Vertex_const_iterator vi(N.vertices_begin());
x_max = CGAL_NTS abs(vi->point().hx()/vi->point().hw());
y_max = CGAL_NTS abs(vi->point().hy()/vi->point().hw());
z_max = CGAL_NTS abs(vi->point().hz()/vi->point().hw());
for(; vi != N.vertices_end(); ++vi) {
if(CGAL_NTS abs(vi->point().hx()/vi->point().hw()) > x_max)
x_max = CGAL_NTS abs(vi->point().hx()/vi->point().hw());
if(CGAL_NTS abs(vi->point().hy()/vi->point().hw()) > y_max)
y_max = CGAL_NTS abs(vi->point().hy()/vi->point().hw());
if(CGAL_NTS abs(vi->point().hz()/vi->point().hw()) > z_max)
z_max = CGAL_NTS abs(vi->point().hz()/vi->point().hw());
}
x_max*105/100;
y_max*105/100;
z_max*105/100;
F.transform(Aff_transformation_3(x_max,0,0, 0,y_max,0, 0,0,z_max, 1));
F.transform(Aff_transformation_3(CGAL::TRANSLATION,Vector_3(0,0,z_max)));
}