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Diffstat (limited to 'src/boost/libs/graph/example/planar_face_traversal.cpp')
-rw-r--r-- | src/boost/libs/graph/example/planar_face_traversal.cpp | 99 |
1 files changed, 99 insertions, 0 deletions
diff --git a/src/boost/libs/graph/example/planar_face_traversal.cpp b/src/boost/libs/graph/example/planar_face_traversal.cpp new file mode 100644 index 000000000..f67e34c0d --- /dev/null +++ b/src/boost/libs/graph/example/planar_face_traversal.cpp @@ -0,0 +1,99 @@ +//======================================================================= +// 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; +} |