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  26 <div class="titlepage"><div><div><h4 class="title">
  27 <a name="geometry.reference.strategies.strategy_buffer_point_circle"></a><a class="link" href="strategy_buffer_point_circle.html" title="strategy::buffer::point_circle">strategy::buffer::point_circle</a>
  28 </h4></div></div></div>
  29 <p>
  30           <a class="indexterm" name="idm46186974177392"></a><a class="indexterm" name="idm46186974176704"></a><a class="indexterm" name="idm46186974176016"></a>
  31 Create a circular buffer around a point.
  32         </p>
  33 <h6>
  34 <a name="geometry.reference.strategies.strategy_buffer_point_circle.h0"></a>
  35           <span class="phrase"><a name="geometry.reference.strategies.strategy_buffer_point_circle.description"></a></span><a class="link" href="strategy_buffer_point_circle.html#geometry.reference.strategies.strategy_buffer_point_circle.description">Description</a>
  36         </h6>
  37 <p>
  38           This strategy can be used as PointStrategy for the buffer algorithm. It
  39           creates a circular buffer around a point. It can be applied for points
  40           and multi_points, but also for a linestring (if it is degenerate, so consisting
  41           of only one point) and for polygons (if it is degenerate). This strategy
  42           is only applicable for Cartesian coordinate systems.
  43         </p>
  44 <h6>
  45 <a name="geometry.reference.strategies.strategy_buffer_point_circle.h1"></a>
  46           <span class="phrase"><a name="geometry.reference.strategies.strategy_buffer_point_circle.synopsis"></a></span><a class="link" href="strategy_buffer_point_circle.html#geometry.reference.strategies.strategy_buffer_point_circle.synopsis">Synopsis</a>
  47         </h6>
  48 <p>
  49 </p>
  50 <pre class="programlisting"><span class="keyword">class</span> <span class="identifier">strategy</span><span class="special">::</span><span class="identifier">buffer</span><span class="special">::</span><span class="identifier">point_circle</span>
  51 <span class="special">{</span>
  52   <span class="comment">// ...</span>
  53 <span class="special">};</span>
  54 </pre>
  55 <p>
  56         </p>
  57 <h6>
  58 <a name="geometry.reference.strategies.strategy_buffer_point_circle.h2"></a>
  59           <span class="phrase"><a name="geometry.reference.strategies.strategy_buffer_point_circle.constructor_s_"></a></span><a class="link" href="strategy_buffer_point_circle.html#geometry.reference.strategies.strategy_buffer_point_circle.constructor_s_">Constructor(s)</a>
  60         </h6>
  61 <div class="informaltable"><table class="table">
  62 <colgroup>
  63 <col>
  64 <col>
  65 <col>
  66 </colgroup>
  67 <thead><tr>
  68 <th>
  69                   <p>
  70                     Function
  71                   </p>
  72                 </th>
  73 <th>
  74                   <p>
  75                     Description
  76                   </p>
  77                 </th>
  78 <th>
  79                   <p>
  80                     Parameters
  81                   </p>
  82                 </th>
  83 </tr></thead>
  84 <tbody><tr>
  85 <td>
  86                   <p>
  87 </p>
  88 <pre xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="table-programlisting"><span class="identifier">point_circle</span><span class="special">(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span class="identifier">count</span> <span class="special">=</span> <span class="number">90</span><span class="special">)</span></pre>
  89 <p>
  90                   </p>
  91                 </td>
  92 <td>
  93                   <p>
  94                     Constructs the strategy.
  95                   </p>
  96                 </td>
  97 <td>
  98                   <p>
  99                     <span class="bold"><strong>std::size_t</strong></span>: <span class="emphasis"><em>count</em></span>:
 100                     number of points for the created circle (if count is smaller
 101                     than 3, count is internally set to 3)
 102                   </p>
 103                 </td>
 104 </tr></tbody>
 105 </table></div>
 106 <h6>
 107 <a name="geometry.reference.strategies.strategy_buffer_point_circle.h3"></a>
 108           <span class="phrase"><a name="geometry.reference.strategies.strategy_buffer_point_circle.header"></a></span><a class="link" href="strategy_buffer_point_circle.html#geometry.reference.strategies.strategy_buffer_point_circle.header">Header</a>
 109         </h6>
 110 <p>
 111           <code class="computeroutput"><span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">geometry</span><span class="special">/</span><span class="identifier">strategies</span><span class="special">/</span><span class="identifier">cartesian</span><span class="special">/</span><span class="identifier">buffer_point_circle</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span></code>
 112         </p>
 113 <h6>
 114 <a name="geometry.reference.strategies.strategy_buffer_point_circle.h4"></a>
 115           <span class="phrase"><a name="geometry.reference.strategies.strategy_buffer_point_circle.example"></a></span><a class="link" href="strategy_buffer_point_circle.html#geometry.reference.strategies.strategy_buffer_point_circle.example">Example</a>
 116         </h6>
 117 <p>
 118           Shows how the point_circle strategy can be used as a PointStrategy to create
 119           circular buffers around points
 120         </p>
 121 <p>
 122 </p>
 123 <pre class="programlisting"><span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">geometry</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
 124 <span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">geometry</span><span class="special">/</span><span class="identifier">geometries</span><span class="special">/</span><span class="identifier">point_xy</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
 125 <span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">geometry</span><span class="special">/</span><span class="identifier">geometries</span><span class="special">/</span><span class="identifier">geometries</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
 126
 127
 128 <span class="keyword">int</span> <span class="identifier">main</span><span class="special">()</span>
 129 <span class="special">{</span>
 130     <span class="keyword">typedef</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">geometry</span><span class="special">::</span><span class="identifier">model</span><span class="special">::</span><span class="identifier">d2</span><span class="special">::</span><span class="identifier">point_xy</span><span class="special">&lt;</span><span class="keyword">double</span><span class="special">&gt;</span> <span class="identifier">point</span><span class="special">;</span>
 131     <span class="keyword">typedef</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">geometry</span><span class="special">::</span><span class="identifier">model</span><span class="special">::</span><span class="identifier">polygon</span><span class="special">&lt;</span><span class="identifier">point</span><span class="special">&gt;</span> <span class="identifier">polygon</span><span class="special">;</span>
 132
 133     <span class="comment">// Declare the point_circle strategy</span>
 134     <span class="identifier">boost</span><span class="special">::</span><span class="identifier">geometry</span><span class="special">::</span><span class="identifier">strategy</span><span class="special">::</span><span class="identifier">buffer</span><span class="special">::</span><span class="identifier">point_circle</span> <span class="identifier">point_strategy</span><span class="special">(</span><span class="number">360</span><span class="special">);</span>
 135
 136     <span class="comment">// Declare other strategies</span>
 137     <span class="identifier">boost</span><span class="special">::</span><span class="identifier">geometry</span><span class="special">::</span><span class="identifier">strategy</span><span class="special">::</span><span class="identifier">buffer</span><span class="special">::</span><span class="identifier">distance_symmetric</span><span class="special">&lt;</span><span class="keyword">double</span><span class="special">&gt;</span> <span class="identifier">distance_strategy</span><span class="special">(</span><span class="number">0.7</span><span class="special">);</span>
 138     <span class="identifier">boost</span><span class="special">::</span><span class="identifier">geometry</span><span class="special">::</span><span class="identifier">strategy</span><span class="special">::</span><span class="identifier">buffer</span><span class="special">::</span><span class="identifier">join_round</span> <span class="identifier">join_strategy</span><span class="special">;</span>
 139     <span class="identifier">boost</span><span class="special">::</span><span class="identifier">geometry</span><span class="special">::</span><span class="identifier">strategy</span><span class="special">::</span><span class="identifier">buffer</span><span class="special">::</span><span class="identifier">end_round</span> <span class="identifier">end_strategy</span><span class="special">;</span>
 140     <span class="identifier">boost</span><span class="special">::</span><span class="identifier">geometry</span><span class="special">::</span><span class="identifier">strategy</span><span class="special">::</span><span class="identifier">buffer</span><span class="special">::</span><span class="identifier">side_straight</span> <span class="identifier">side_strategy</span><span class="special">;</span>
 141
 142     <span class="comment">// Declare/fill of a multi point</span>
 143     <span class="identifier">boost</span><span class="special">::</span><span class="identifier">geometry</span><span class="special">::</span><span class="identifier">model</span><span class="special">::</span><span class="identifier">multi_point</span><span class="special">&lt;</span><span class="identifier">point</span><span class="special">&gt;</span> <span class="identifier">mp</span><span class="special">;</span>
 144     <span class="identifier">boost</span><span class="special">::</span><span class="identifier">geometry</span><span class="special">::</span><span class="identifier">read_wkt</span><span class="special">(</span><span class="string">"MULTIPOINT((3 3),(3 4),(4 4),(7 3))"</span><span class="special">,</span> <span class="identifier">mp</span><span class="special">);</span>
 145
 146     <span class="comment">// Create the buffer of a multi point</span>
 147     <span class="identifier">boost</span><span class="special">::</span><span class="identifier">geometry</span><span class="special">::</span><span class="identifier">model</span><span class="special">::</span><span class="identifier">multi_polygon</span><span class="special">&lt;</span><span class="identifier">polygon</span><span class="special">&gt;</span> <span class="identifier">result</span><span class="special">;</span>
 148     <span class="identifier">boost</span><span class="special">::</span><span class="identifier">geometry</span><span class="special">::</span><span class="identifier">buffer</span><span class="special">(</span><span class="identifier">mp</span><span class="special">,</span> <span class="identifier">result</span><span class="special">,</span>
 149                 <span class="identifier">distance_strategy</span><span class="special">,</span> <span class="identifier">side_strategy</span><span class="special">,</span>
 150                 <span class="identifier">join_strategy</span><span class="special">,</span> <span class="identifier">end_strategy</span><span class="special">,</span> <span class="identifier">point_strategy</span><span class="special">);</span>
 151
 152
 153     <span class="keyword">return</span> <span class="number">0</span><span class="special">;</span>
 154 <span class="special">}</span>
 155 </pre>
 156 <p>
 157         </p>
 158 <h6>
 159 <a name="geometry.reference.strategies.strategy_buffer_point_circle.h5"></a>
 160           <span class="phrase"><a name="geometry.reference.strategies.strategy_buffer_point_circle.output"></a></span><a class="link" href="strategy_buffer_point_circle.html#geometry.reference.strategies.strategy_buffer_point_circle.output">Output</a>
 161         </h6>
 162 <p>
 163           <span class="inlinemediaobject"><img src="../../../img/strategies/buffer_point_circle.png" alt="buffer_point_circle"></span>
 164         </p>
 165 <h6>
 166 <a name="geometry.reference.strategies.strategy_buffer_point_circle.h6"></a>
 167           <span class="phrase"><a name="geometry.reference.strategies.strategy_buffer_point_circle.see_also"></a></span><a class="link" href="strategy_buffer_point_circle.html#geometry.reference.strategies.strategy_buffer_point_circle.see_also">See
 168           also</a>
 169         </h6>
 170 <div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
 171 <li class="listitem">
 172               <a class="link" href="../algorithms/buffer/buffer_7_with_strategies.html" title="buffer (with strategies)">buffer
 173               (with strategies)</a>
 174             </li>
 175 <li class="listitem">
 176               <a class="link" href="strategy_buffer_point_square.html" title="strategy::buffer::point_square">point_square</a>
 177             </li>
 178 <li class="listitem">
 179               <a class="link" href="strategy_buffer_geographic_point_circle.html" title="strategy::buffer::geographic_point_circle">geographic_point_circle</a>
 180             </li>
 181 </ul></div>
 182 </div>
 183 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 184 <td align="left"></td>
 185 <td align="right"><div class="copyright-footer">Copyright &#169; 2009-2019 Barend Gehrels, Bruno Lalande, Mateusz Loskot, Adam
 186       Wulkiewicz, Oracle and/or its affiliates<p>
 187         Distributed under the Boost Software License, Version 1.0. (See accompanying
 188         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
 189       </p>
 190 </div></td>
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