1 //=======================================================================
2 // Copyright 2007 Aaron Windsor
3 //
4 // Distributed under the Boost Software License, Version 1.0. (See
5 // accompanying file LICENSE_1_0.txt or copy at
6 // http://www.boost.org/LICENSE_1_0.txt)
7 //=======================================================================
8 #include <iostream>
9 #include <boost/graph/adjacency_list.hpp>
10 #include <boost/graph/properties.hpp>
11 #include <boost/graph/graph_traits.hpp>
12 #include <boost/property_map/property_map.hpp>
13 #include <boost/ref.hpp>
14 #include <vector>
15
16 #include <boost/graph/planar_face_traversal.hpp>
17 #include <boost/graph/boyer_myrvold_planar_test.hpp>
18
19 using namespace boost;
20
21 // Some planar face traversal visitors that will
22 // print the vertices and edges on the faces
23
24 struct output_visitor : public planar_face_traversal_visitor
25 {
begin_faceoutput_visitor26 void begin_face() { std::cout << "New face: "; }
end_faceoutput_visitor27 void end_face() { std::cout << std::endl; }
28 };
29
30 struct vertex_output_visitor : public output_visitor
31 {
next_vertexvertex_output_visitor32 template < typename Vertex > void next_vertex(Vertex v)
33 {
34 std::cout << v << " ";
35 }
36 };
37
38 struct edge_output_visitor : public output_visitor
39 {
next_edgeedge_output_visitor40 template < typename Edge > void next_edge(Edge e) { std::cout << e << " "; }
41 };
42
main(int argc,char ** argv)43 int main(int argc, char** argv)
44 {
45
46 typedef adjacency_list< vecS, vecS, undirectedS,
47 property< vertex_index_t, int >, property< edge_index_t, int > >
48 graph;
49
50 // Create a graph - this is a biconnected, 3 x 3 grid.
51 // It should have four small (four vertex/four edge) faces and
52 // one large face that contains all but the interior vertex
53 graph g(9);
54
55 add_edge(0, 1, g);
56 add_edge(1, 2, g);
57
58 add_edge(3, 4, g);
59 add_edge(4, 5, g);
60
61 add_edge(6, 7, g);
62 add_edge(7, 8, g);
63
64 add_edge(0, 3, g);
65 add_edge(3, 6, g);
66
67 add_edge(1, 4, g);
68 add_edge(4, 7, g);
69
70 add_edge(2, 5, g);
71 add_edge(5, 8, g);
72
73 // Initialize the interior edge index
74 property_map< graph, edge_index_t >::type e_index = get(edge_index, g);
75 graph_traits< graph >::edges_size_type edge_count = 0;
76 graph_traits< graph >::edge_iterator ei, ei_end;
77 for (boost::tie(ei, ei_end) = edges(g); ei != ei_end; ++ei)
78 put(e_index, *ei, edge_count++);
79
80 // Test for planarity - we know it is planar, we just want to
81 // compute the planar embedding as a side-effect
82 typedef std::vector< graph_traits< graph >::edge_descriptor > vec_t;
83 std::vector< vec_t > embedding(num_vertices(g));
84 if (boyer_myrvold_planarity_test(boyer_myrvold_params::graph = g,
85 boyer_myrvold_params::embedding = &embedding[0]))
86 std::cout << "Input graph is planar" << std::endl;
87 else
88 std::cout << "Input graph is not planar" << std::endl;
89
90 std::cout << std::endl << "Vertices on the faces: " << std::endl;
91 vertex_output_visitor v_vis;
92 planar_face_traversal(g, &embedding[0], v_vis);
93
94 std::cout << std::endl << "Edges on the faces: " << std::endl;
95 edge_output_visitor e_vis;
96 planar_face_traversal(g, &embedding[0], e_vis);
97
98 return 0;
99 }
100