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//=======================================================================
// Copyright 2007 Aaron Windsor
//
// Distributed under the Boost Software License, Version 1.0. (See
// accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
//=======================================================================
#include <iostream>
#include <boost/graph/adjacency_list.hpp>
#include <boost/graph/properties.hpp>
#include <boost/graph/graph_traits.hpp>
#include <boost/property_map/property_map.hpp>
#include <boost/ref.hpp>
#include <vector>
#include <boost/graph/planar_face_traversal.hpp>
#include <boost/graph/boyer_myrvold_planar_test.hpp>
using namespace boost;
// Some planar face traversal visitors that will
// print the vertices and edges on the faces
struct output_visitor : public planar_face_traversal_visitor
{
void begin_face() { std::cout << "New face: "; }
void end_face() { std::cout << std::endl; }
};
struct vertex_output_visitor : public output_visitor
{
template < typename Vertex > void next_vertex(Vertex v)
{
std::cout << v << " ";
}
};
struct edge_output_visitor : public output_visitor
{
template < typename Edge > void next_edge(Edge e) { std::cout << e << " "; }
};
int main(int argc, char** argv)
{
typedef adjacency_list< vecS, vecS, undirectedS,
property< vertex_index_t, int >, property< edge_index_t, int > >
graph;
// Create a graph - this is a biconnected, 3 x 3 grid.
// It should have four small (four vertex/four edge) faces and
// one large face that contains all but the interior vertex
graph g(9);
add_edge(0, 1, g);
add_edge(1, 2, g);
add_edge(3, 4, g);
add_edge(4, 5, g);
add_edge(6, 7, g);
add_edge(7, 8, g);
add_edge(0, 3, g);
add_edge(3, 6, g);
add_edge(1, 4, g);
add_edge(4, 7, g);
add_edge(2, 5, g);
add_edge(5, 8, g);
// Initialize the interior edge index
property_map< graph, edge_index_t >::type e_index = get(edge_index, g);
graph_traits< graph >::edges_size_type edge_count = 0;
graph_traits< graph >::edge_iterator ei, ei_end;
for (boost::tie(ei, ei_end) = edges(g); ei != ei_end; ++ei)
put(e_index, *ei, edge_count++);
// Test for planarity - we know it is planar, we just want to
// compute the planar embedding as a side-effect
typedef std::vector< graph_traits< graph >::edge_descriptor > vec_t;
std::vector< vec_t > embedding(num_vertices(g));
if (boyer_myrvold_planarity_test(boyer_myrvold_params::graph = g,
boyer_myrvold_params::embedding = &embedding[0]))
std::cout << "Input graph is planar" << std::endl;
else
std::cout << "Input graph is not planar" << std::endl;
std::cout << std::endl << "Vertices on the faces: " << std::endl;
vertex_output_visitor v_vis;
planar_face_traversal(g, &embedding[0], v_vis);
std::cout << std::endl << "Edges on the faces: " << std::endl;
edge_output_visitor e_vis;
planar_face_traversal(g, &embedding[0], e_vis);
return 0;
}
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