ceph/src/boost/libs/graph/example/straight_line_drawing.cpp

   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 <vector>
  14
  15 #include <boost/graph/planar_canonical_ordering.hpp>
  16 #include <boost/graph/is_straight_line_drawing.hpp>
  17 #include <boost/graph/chrobak_payne_drawing.hpp>
  18 #include <boost/graph/boyer_myrvold_planar_test.hpp>
  19
  20 using namespace boost;
  21
  22 // a class to hold the coordinates of the straight line embedding
  23 struct coord_t
  24 {
  25     std::size_t x;
  26     std::size_t y;
  27 };
  28
  29 int main(int argc, char** argv)
  30 {
  31     typedef adjacency_list< vecS, vecS, undirectedS,
  32         property< vertex_index_t, int > >
  33         graph;
  34
  35     // Define the storage type for the planar embedding
  36     typedef std::vector< std::vector< graph_traits< graph >::edge_descriptor > >
  37         embedding_storage_t;
  38     typedef boost::iterator_property_map< embedding_storage_t::iterator,
  39         property_map< graph, vertex_index_t >::type >
  40         embedding_t;
  41
  42     // Create the graph - a maximal planar graph on 7 vertices. The functions
  43     // planar_canonical_ordering and chrobak_payne_straight_line_drawing both
  44     // require a maximal planar graph. If you start with a graph that isn't
  45     // maximal planar (or you're not sure), you can use the functions
  46     // make_connected, make_biconnected_planar, and make_maximal planar in
  47     // sequence to add a set of edges to any undirected planar graph to make
  48     // it maximal planar.
  49
  50     graph g(7);
  51     add_edge(0, 1, g);
  52     add_edge(1, 2, g);
  53     add_edge(2, 3, g);
  54     add_edge(3, 0, g);
  55     add_edge(3, 4, g);
  56     add_edge(4, 5, g);
  57     add_edge(5, 6, g);
  58     add_edge(6, 3, g);
  59     add_edge(0, 4, g);
  60     add_edge(1, 3, g);
  61     add_edge(3, 5, g);
  62     add_edge(2, 6, g);
  63     add_edge(1, 4, g);
  64     add_edge(1, 5, g);
  65     add_edge(1, 6, g);
  66
  67     // Create the planar embedding
  68     embedding_storage_t embedding_storage(num_vertices(g));
  69     embedding_t embedding(embedding_storage.begin(), get(vertex_index, g));
  70
  71     boyer_myrvold_planarity_test(boyer_myrvold_params::graph = g,
  72         boyer_myrvold_params::embedding = embedding);
  73
  74     // Find a canonical ordering
  75     std::vector< graph_traits< graph >::vertex_descriptor > ordering;
  76     planar_canonical_ordering(g, embedding, std::back_inserter(ordering));
  77
  78     // Set up a property map to hold the mapping from vertices to coord_t's
  79     typedef std::vector< coord_t > straight_line_drawing_storage_t;
  80     typedef boost::iterator_property_map<
  81         straight_line_drawing_storage_t::iterator,
  82         property_map< graph, vertex_index_t >::type >
  83         straight_line_drawing_t;
  84
  85     straight_line_drawing_storage_t straight_line_drawing_storage(
  86         num_vertices(g));
  87     straight_line_drawing_t straight_line_drawing(
  88         straight_line_drawing_storage.begin(), get(vertex_index, g));
  89
  90     // Compute the straight line drawing
  91     chrobak_payne_straight_line_drawing(
  92         g, embedding, ordering.begin(), ordering.end(), straight_line_drawing);
  93
  94     std::cout << "The straight line drawing is: " << std::endl;
  95     graph_traits< graph >::vertex_iterator vi, vi_end;
  96     for (boost::tie(vi, vi_end) = vertices(g); vi != vi_end; ++vi)
  97     {
  98         coord_t coord(get(straight_line_drawing, *vi));
  99         std::cout << *vi << " -> (" << coord.x << ", " << coord.y << ")"
 100                   << std::endl;
 101     }
 102
 103     // Verify that the drawing is actually a plane drawing
 104     if (is_straight_line_drawing(g, straight_line_drawing))
 105         std::cout << "Is a plane drawing." << std::endl;
 106     else
 107         std::cout << "Is not a plane drawing." << std::endl;
 108
 109     return 0;
 110 }