void print_endpoint(Halfedge_handle e, bool is_src) { std::cout << "\t"; if ( is_src ) { if ( e->has_source() ) std::cout << e->source()->point() << std::endl; else std::cout << "point at infinity" << std::endl; } else { if ( e->has_target() ) std::cout << e->target()->point() << std::endl; else std::cout << "point at infinity" << std::endl; } }