C++ Tr::finite_cells_begin方法代码示例

int main(int , char** argv)
{
  Tr tr;
  C2T3 c2t3(tr);

  std::ifstream ifs(argv[1]);
  if( !ifs )
  {
    std::cerr << "Usage:\n"
              << "  " << argv[0] << " FILE\n"
              << "\n"
	      << "  FILE must be " << format_cgal_description
              << "\n";
    return EXIT_FAILURE;
  }

  std::cout << "  Reading " << argv[1] << std::endl;

  if( CGAL::Mesh_3::input_mesh(ifs, c2t3,
                               true,
                               &std::cerr) )
//   if( CGAL::input_pslg_from_medit(ifs,
//                                   c2t3,
//                                   true,         // debug
//                                   &std::cout) ) // debug to cout
  {
    display_faces_counts(tr, "    ", &std::cout);

    std::cout << "\n  Statistics:\n";

    std::cout << "(vertices)\n";
    display_vertices_by_surface_indices_statistics(tr, "    ", &std::cout);

    std::cout << "(facets)\n";
    display_facets_by_surface_indices_statistics(c2t3, "    ", &std::cout);

    Compute_min_angle<Tr> min_angle(tr);

    double min = 180;
    for(Tr::Finite_cells_iterator cit = tr.finite_cells_begin();
	cit != tr.finite_cells_end();
	++cit)
      if(cit->is_in_domain())
      {
	const double angle = min_angle(cit);
	if( angle < min ) min = angle;
      }
	
    std::cout << "\nmin angle: " << min << "\n";

    return EXIT_SUCCESS;
  }
  else
    return EXIT_FAILURE;
}

int main()
{
  Tr::Point p1(0,0,0);
  Tr::Point p2(1,0,0);
  Tr::Point p3(0,1,0);
  Tr::Point p4(0,0,1);
  
  Tr tr;
  tr.insert(p1);
  tr.insert(p2);
  tr.insert(p3);
  tr.insert(p4);
  
  Tr::Cell_handle ch = tr.finite_cells_begin();
  int k = 0;
  Tr::Facet f = std::make_pair(ch,k);
  Tr::Cell::Subdomain_index sub_index = 1;
  Tr::Cell::Surface_patch_index surf_index = 2;
  Tr::Cell::Surface_patch_index surf_index_bis = 21;
  Tr::Vertex::Index index (surf_index);
  Tr::Vertex::Index index_bis(surf_index_bis);
  
  // Init cell
  tr.dual(ch);
  ch->set_subdomain_index(sub_index);
  
  // Init facet
  Tr::Bare_point facet_circum =
    tr.geom_traits().construct_weighted_circumcenter_3_object()(
      tr.point(ch, k+1), tr.point(ch, k+2), tr.point(ch, k+3));

  ch->set_surface_patch_index(k,surf_index);
  ch->set_facet_surface_center(k,facet_circum);
  ch->set_facet_surface_center_index(k,index);
  
  // Init vertices
  ch->vertex(0)->set_dimension(2);
  ch->vertex(1)->set_dimension(2);
  ch->vertex(2)->set_dimension(2);
  ch->vertex(3)->set_dimension(2);
  
  ch->vertex(0)->set_index(index);
  ch->vertex(1)->set_index(index);
  ch->vertex(2)->set_index(index_bis);
  ch->vertex(3)->set_index(index_bis);
  
  // -----------------------------------
  // Test edge criteria
  // -----------------------------------
  Tr::Bare_point bp1 = tr.geom_traits().construct_point_3_object()(p1);

  Mc ec1(edge_size = 1);
  assert( ec1.edge_criteria_object().sizing_field(bp1,1,index) == 1 );
  
  Mc ec2(edge_sizing_field = Esf(2));
  assert( ec2.edge_criteria_object().sizing_field(bp1,1,index) == 2 );

  Mc ec3(edge_sizing_field = 3.);
  assert( ec3.edge_criteria_object().sizing_field(bp1,1,index) == 3 );
  
  Mc ec4(edge_size = 4.1,
         edge_sizing_field = Esf(4.2));
  assert( ec4.edge_criteria_object().sizing_field(bp1,1,index) == 4.1 );
  
  Mc ec5(sizing_field = 5.);
  assert( ec5.edge_criteria_object().sizing_field(bp1,1,index) == 5 );
  
  Mc ec6(sizing_field = 6.1,
         edge_sizing_field = 6.2);
  assert( ec6.edge_criteria_object().sizing_field(bp1,1,index) == 6.2 );
  
  Mc ec7(sizing_field = 7.1,
         edge_size = 7.2);
  assert( ec7.edge_criteria_object().sizing_field(bp1,1,index) == 7.2 );
  
  
  // -----------------------------------
  // Test facet criteria
  // -----------------------------------
  typedef Tr::Geom_traits::FT FT;
  Tr::Geom_traits::Compute_squared_radius_3 squared_radius = tr.geom_traits().compute_squared_radius_3_object();
  Tr::Geom_traits::Construct_point_3 cp = tr.geom_traits().construct_point_3_object();

  FT radius_facet = CGAL::sqrt(squared_radius(cp(tr.point(ch, k+1)),
                                              cp(tr.point(ch, k+2)),
                                              cp(tr.point(ch, k+3))));

  FT facet_size_ok = radius_facet*FT(10);
  FT facet_size_nok = radius_facet/FT(10);

  Mc fc1(facet_size = facet_size_ok);
  assert( ! fc1.facet_criteria_object()(tr, f) );

  Mc fc2(facet_sizing_field = facet_size_ok);
  assert( ! fc2.facet_criteria_object()(tr, f) );

  Mc fc3(facet_sizing_field = Fsf(facet_size_ok));
  assert( ! fc3.facet_criteria_object()(tr, f) );

  Mc fc4(facet_sizing_field = facet_size_nok,
//.........这里部分代码省略.........

int main()
{
	CGAL::Timer t;
	t.start();
	// Define functions
	Function f1(&torus_function);
	Function f2(&sphere_function<5>);
	Function f3(&tanglecube_function);
	Function f4(&heart_function);
	Function f5(&klein_function);
	Function f6(&false_knot_function);
	Function f7(&knot1_function);
	Function f8(&octic_function);

	Function_vector v;
	v.push_back(&f1);
	//v.push_back(&f2);
	//v.push_back(&f3);
	//v.push_back(&f4);
	//v.push_back(&f5);
	//v.push_back(&f6);
	//v.push_back(&f7);
	//v.push_back(&f8);

	// Domain (Warning: Sphere_3 constructor uses square radius !)
	Mesh_domain domain(v, K::Sphere_3(CGAL::ORIGIN, 5.*5.), 1e-6);

	// Set mesh criteria
	Facet_criteria facet_criteria(30, 0.2, 0.02); // angle, size, approximation
	Cell_criteria cell_criteria(2., 0.4); // radius-edge ratio, size
	Mesh_criteria criteria(facet_criteria, cell_criteria);

	// Mesh generation
	C3t3 c3t3 = CGAL::make_mesh_3<C3t3>(domain, criteria, no_exude(), no_perturb());

	// Perturbation (maximum cpu time: 10s, targeted dihedral angle: default)
	CGAL::perturb_mesh_3(c3t3, domain, time_limit = 10);
	
	// Exudation
	CGAL::exude_mesh_3(c3t3,12);

	CGAL::Random rand;

	t.stop();
	std::cout << "Time elapsed for building the mesh: " << t.time() << std::endl;
	t.reset();
	
	t.start();
	int nr = 1500;
	std::vector<Point> points;
	points.reserve(nr);
	CGAL::Random_points_in_mesh_3<Point, C3t3, FastPolicy> g(c3t3);
	t.stop();
	std::cout << "Time elapsed for init Random_points_in_mesh_3: " <<
		t.time() << std::endl;
	t.reset();

	t.start();
	CGAL::cpp11::copy_n( g, nr, std::back_inserter(points));
	t.stop();
	std::cout << "Time elapsed for generating the points: " << t.time() << std::endl;
	t.reset();

	Tr tr = c3t3.triangulation();
	Tetrahedron3 tet;
	Tr::Finite_cells_iterator it = tr.finite_cells_begin();
	for (; it != tr.finite_cells_end(); it++) {
		if (c3t3.is_in_complex(it)) {
			tet = tr.tetrahedron(it);
			break;
		}
	}

	t.start();
	std::vector<Point> points_tet;
	points_tet.reserve(nr);
	CGAL::Random_points_in_tetrahedron_3<Point> g1(tet);
	CGAL::cpp11::copy_n(g1, nr, std::back_inserter(points_tet));
	t.stop();
	std::cout << "Time elapsed for " << nr << " points in one tetrahedron: " <<
		t.time() << std::endl;
	t.reset();

	std::cout << "The generated points are: " << std::endl;
	for (int i = 0; i < nr; i++) {
		std::cout << points[i].x() << " " << points[i].y() << " " <<
			points[i].z() << std::endl;
	}

	points_tet.clear();
	points.clear();
	v.clear();
	return 0;
}