ceph/src/boost/libs/graph/doc/PlanarFaceVisitor.html

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  10 <TITLE>Planar Face Visitor Concept</TITLE>
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  19 <H1>Planar Face Visitor Concept</H1>
  20
  21 This concept defines the visitor interface for
  22 <a href="./planar_face_traversal.html"><tt>planar_face_traversal</tt></a>.
  23 Users can define a class with the Planar Face Visitor interface and pass an
  24 object of the class to <tt>planar_face_traversal</tt>, thereby augmenting the
  25 actions taken during the traversal. Note that objects passed to
  26 <tt>planar_face_traversal</tt> are passed by reference.
  27
  28 <h3>Notation</h3>
  29
  30 <table>
  31 <tbody><tr>
  32 <td><tt>V</tt></td>
  33 <td>A type that is a model of Planar Face Visitor.</td>
  34 </tr>
  35
  36 <tr>
  37 <td><tt>vis</tt></td>
  38 <td>An object of type <tt>V</tt>.</td>
  39 </tr>
  40
  41 <tr>
  42 <td><tt>G</tt></td>
  43 <td>A type that is a model of Graph.</td>
  44 </tr>
  45
  46 <tr>
  47 <td><tt>e</tt></td>
  48 <td>An object of type <tt>boost::graph_traits&lt;G&gt;::edge_descriptor</tt>.
  49 </td>
  50 </tr>
  51
  52 <tr>
  53 <td><tt>v</tt></td>
  54 <td>An object of type <tt>boost::graph_traits&lt;G&gt;::vertex_descriptor</tt>.
  55 </td>
  56 </tr>
  57
  58 </tbody></table>
  59
  60
  61 <h3>Valid Expressions</h3>
  62
  63 <table border="1">
  64 <tbody><tr>
  65 <th>Name</th><th>Expression</th><th>Return Type</th><th>Description</th>
  66 </tr>
  67
  68 <tr>
  69 <td>Begin Traversal</td>
  70 <td><tt>vis.begin_traversal()</tt></td>
  71 <td><tt>void</tt></td>
  72 <td>
  73 This is invoked once per traversal, before the traversal begins.
  74 </td>
  75 </tr>
  76
  77 <tr>
  78 <td>Begin Face</td>
  79 <td><tt>vis.begin_face()</tt></td>
  80 <td><tt>void</tt></td>
  81 <td>
  82 This is invoked once for each face, before any vertices or edges on the face
  83 are visited.
  84 </td>
  85 </tr>
  86
  87 <tr>
  88 <td>Next Vertex</td>
  89 <td><tt>vis.next_vertex(v)</tt></td>
  90 <td><tt>void</tt></td>
  91 <td>
  92 This is invoked when a vertex is encountered while traversing a face.
  93 </td>
  94 </tr>
  95
  96
  97 <tr>
  98 <td>Next Edge</td>
  99 <td><tt>vis.next_edge(e)</tt></td>
 100 <td><tt>void</tt></td>
 101 <td>
 102 This is invoked when an edge is encountered while traversing a face.
 103 </td>
 104 </tr>
 105
 106 <tr>
 107 <td>End Face</td>
 108 <td><tt>vis.end_face()</tt></td>
 109 <td><tt>void</tt></td>
 110 <td>
 111 This is invoked once for each face, after all vertices and edges on the face
 112 are visited.
 113 </td>
 114 </tr>
 115
 116
 117 <tr>
 118 <td>End Traversal</td>
 119 <td><tt>vis.end_traversal()</tt></td>
 120 <td><tt>void</tt></td>
 121 <td>
 122 This is invoked once per traversal, after the traversal ends.
 123 </td>
 124 </tr>
 125
 126 </tbody></table>
 127
 128 <h3>Models</h3>
 129
 130 <ul>
 131  <li> The file <a href="../../../boost/graph/planar_face_traversal.hpp">
 132 <tt>planar_face_traversal.hpp</tt></a> contains a class
 133 <tt>planar_face_traversal_visitor</tt> that implements empty actions for
 134 all event points of a Planar Face Visitor. In the case where only a few of the
 135 event points of Planar Face Visitor need to be implemented, one can derive from
 136 <tt>planar_face_traversal_visitor</tt> and only implement the necessary event
 137 points. <li> The implementation of <a href="./make_maximal_planar.html">
 138 <tt>make_maximal_planar</tt></a> uses a <tt>triangulation_visitor</tt> that is
 139 a model of Planar Face Visitor.
 140 </li>
 141 </ul>
 142
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 145 Copyright &copy; 2007 Aaron Windsor (<a href="mailto:aaron.windsor@gmail.com">
 146 aaron.windsor@gmail.com</a>)
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