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

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  10 <Title>Boost Graph Library: is_straight_line_drawing</Title>
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  18 <H1><tt>is_straight_line_drawing</tt></H1>
  19
  20 <p>
  21 <pre>
  22 template &lt;typename Graph, typename GridPositionMap, typename VertexIndexMap&gt;
  23 bool is_straight_line_drawing(const Graph& g, GridPositionMap drawing, VertexIndexMap vm);
  24 </pre>
  25
  26 <p>
  27 If <tt>drawing</tt> is a property map modeling the PositionMap
  28 concept, <tt>is_straight_line_drawing</tt> returns true exactly when no two of
  29 the line segments induced by edges in the graph under <tt>drawing</tt>
  30 intersect. This function works correctly in the presence of self-loops and
  31 parallel edges, and can be used to verify the output of the function
  32 <tt>
  33 <a href="straight_line_drawing.html">chrobak_payne_straight_line_embedding.</a>
  34 </tt>
  35
  36 <p>
  37
  38 <h3>Complexity</h3>
  39
  40 Runs in time <i>O(n log n)</i> on a planar graph with <i>n</i> vertices.
  41
  42 <H3>Where Defined</H3>
  43
  44 <P>
  45 <a href="../../../boost/graph/is_straight_line_drawing.hpp"><TT>boost/graph/is_straight_line_drawing.hpp</TT></a>
  46
  47 <h3>Parameters</h3>
  48
  49 IN: <tt>Graph&amp; g</tt>
  50
  51 <blockquote>
  52 An undirected graph. The graph type must be a model of <a
  53 href="EdgeListGraph.html">Edge List Graph</a>
  54 </blockquote>
  55
  56 IN: <tt>PositionMap</tt>
  57
  58 <blockquote>
  59 A <a href="../../property_map/doc/LvaluePropertyMap.html">Readable LValue Property
  60 Map</a> that models the Position Map concept. The Position Map concept requires
  61 that the value mapped to be an object that has members <tt>x</tt> and
  62 <tt>y</tt>. For example, if <tt>p</tt> models PositionMap and <tt>v</tt>
  63 is a vertex in the graph, <tt>p[v].x</tt> and <tt>p[v].y</tt> are valid
  64 expressions. The type of <tt>x</tt> and <tt>y</tt> must be implicitly
  65 convertable to <tt>std::size_t</tt>.
  66 </blockquote>
  67
  68 IN: <tt>VertexIndexMap vm</tt>
  69
  70 <blockquote>
  71 A <a href="../../property_map/doc/ReadablePropertyMap.html">Readable Property Map</a> that maps vertices from <tt>g</tt> to distinct integers in the range <tt>[0, num_vertices(g) )</tt><br>
  72 <b>Default</b>: <tt>get(vertex_index,g)</tt><br>
  73 </blockquote>
  74
  75 <H3>Example</H3>
  76
  77 <P>
  78 <a href="../example/straight_line_drawing.cpp"><TT>examples/straight_line_drawing.cpp</TT></a>
  79
  80 <h3>See Also</h3>
  81
  82 <p>
  83 <ul>
  84 <li><a href="planar_graphs.html">Planar Graphs in the Boost Graph Library</a>
  85 <li><a href="straight_line_drawing.html">
  86 <tt>chrobak_payne_straight_line_drawing</tt></a>
  87 </ul>
  88
  89 <br>
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  91 Copyright &copy; 2007 Aaron Windsor (<a href="mailto:aaron.windsor@gmail.com">aaron.windsor@gmail.com</a>)
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