libs/geometry/doc/html/geometry/reference/algorithms/densify/densify_3.html

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  26 <div class="titlepage"><div><div><h5 class="title">
  27 <a name="geometry.reference.algorithms.densify.densify_3"></a><a class="link" href="densify_3.html" title="densify">densify</a>
  28 </h5></div></div></div>
  29 <p>
  30             <a class="indexterm" name="idm46187003815360"></a>
  31 Densify a geometry.
  32           </p>
  33 <h6>
  34 <a name="geometry.reference.algorithms.densify.densify_3.h0"></a>
  35             <span class="phrase"><a name="geometry.reference.algorithms.densify.densify_3.synopsis"></a></span><a class="link" href="densify_3.html#geometry.reference.algorithms.densify.densify_3.synopsis">Synopsis</a>
  36           </h6>
  37 <p>
  38 </p>
  39 <pre class="programlisting"><span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">Geometry</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">Distance</span><span class="special">&gt;</span>
  40 <span class="keyword">void</span> <span class="identifier">densify</span><span class="special">(</span><span class="identifier">Geometry</span> <span class="keyword">const</span> <span class="special">&amp;</span> <span class="identifier">geometry</span><span class="special">,</span> <span class="identifier">Geometry</span> <span class="special">&amp;</span> <span class="identifier">out</span><span class="special">,</span> <span class="identifier">Distance</span> <span class="keyword">const</span> <span class="special">&amp;</span> <span class="identifier">max_distance</span><span class="special">)</span></pre>
  41 <p>
  42           </p>
  43 <h6>
  44 <a name="geometry.reference.algorithms.densify.densify_3.h1"></a>
  45             <span class="phrase"><a name="geometry.reference.algorithms.densify.densify_3.parameters"></a></span><a class="link" href="densify_3.html#geometry.reference.algorithms.densify.densify_3.parameters">Parameters</a>
  46           </h6>
  47 <div class="informaltable"><table class="table">
  48 <colgroup>
  49 <col>
  50 <col>
  51 <col>
  52 <col>
  53 </colgroup>
  54 <thead><tr>
  55 <th>
  56                     <p>
  57                       Type
  58                     </p>
  59                   </th>
  60 <th>
  61                     <p>
  62                       Concept
  63                     </p>
  64                   </th>
  65 <th>
  66                     <p>
  67                       Name
  68                     </p>
  69                   </th>
  70 <th>
  71                     <p>
  72                       Description
  73                     </p>
  74                   </th>
  75 </tr></thead>
  76 <tbody>
  77 <tr>
  78 <td>
  79                     <p>
  80                       Geometry const &amp;
  81                     </p>
  82                   </td>
  83 <td>
  84                     <p>
  85                       Any type fulfilling a Geometry Concept
  86                     </p>
  87                   </td>
  88 <td>
  89                     <p>
  90                       geometry
  91                     </p>
  92                   </td>
  93 <td>
  94                     <p>
  95                       Input geometry, to be densified
  96                     </p>
  97                   </td>
  98 </tr>
  99 <tr>
 100 <td>
 101                     <p>
 102                       Geometry &amp;
 103                     </p>
 104                   </td>
 105 <td>
 106                     <p>
 107                       Any type fulfilling a Geometry Concept
 108                     </p>
 109                   </td>
 110 <td>
 111                     <p>
 112                       out
 113                     </p>
 114                   </td>
 115 <td>
 116                     <p>
 117                       Output geometry, densified version of the input geometry
 118                     </p>
 119                   </td>
 120 </tr>
 121 <tr>
 122 <td>
 123                     <p>
 124                       Distance const &amp;
 125                     </p>
 126                   </td>
 127 <td>
 128                     <p>
 129                       A numerical distance measure
 130                     </p>
 131                   </td>
 132 <td>
 133                     <p>
 134                       max_distance
 135                     </p>
 136                   </td>
 137 <td>
 138                     <p>
 139                       Distance threshold (in units depending on coordinate system)
 140                     </p>
 141                   </td>
 142 </tr>
 143 </tbody>
 144 </table></div>
 145 <h6>
 146 <a name="geometry.reference.algorithms.densify.densify_3.h2"></a>
 147             <span class="phrase"><a name="geometry.reference.algorithms.densify.densify_3.header"></a></span><a class="link" href="densify_3.html#geometry.reference.algorithms.densify.densify_3.header">Header</a>
 148           </h6>
 149 <p>
 150             Either
 151           </p>
 152 <p>
 153             <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">hpp</span><span class="special">&gt;</span></code>
 154           </p>
 155 <p>
 156             Or
 157           </p>
 158 <p>
 159             <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">algorithms</span><span class="special">/</span><span class="identifier">densify</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span></code>
 160           </p>
 161 <h6>
 162 <a name="geometry.reference.algorithms.densify.densify_3.h3"></a>
 163             <span class="phrase"><a name="geometry.reference.algorithms.densify.densify_3.conformance"></a></span><a class="link" href="densify_3.html#geometry.reference.algorithms.densify.densify_3.conformance">Conformance</a>
 164           </h6>
 165 <p>
 166             The function densify is not defined by OGC.
 167           </p>
 168 <div class="note"><table border="0" summary="Note">
 169 <tr>
 170 <td rowspan="2" align="center" valign="top" width="25"><img alt="[Note]" src="../../../../../../../../doc/src/images/note.png"></td>
 171 <th align="left">Note</th>
 172 </tr>
 173 <tr><td align="left" valign="top"><p>
 174               PostGIS contains an algorithm ST_Segmentize with the same functionality.
 175               See the <a href="http://www.postgis.org/docs/ST_Segmentize.html" target="_top">PostGIS
 176               documentation</a>.
 177             </p></td></tr>
 178 </table></div>
 179 <h6>
 180 <a name="geometry.reference.algorithms.densify.densify_3.h4"></a>
 181             <span class="phrase"><a name="geometry.reference.algorithms.densify.densify_3.behavior"></a></span><a class="link" href="densify_3.html#geometry.reference.algorithms.densify.densify_3.behavior">Behavior</a>
 182           </h6>
 183 <p>
 184             The algorithm divides segments of a geometry if they are longer than
 185             passed distance into smaller segments.
 186           </p>
 187 <div class="note"><table border="0" summary="Note">
 188 <tr>
 189 <td rowspan="2" align="center" valign="top" width="25"><img alt="[Note]" src="../../../../../../../../doc/src/images/note.png"></td>
 190 <th align="left">Note</th>
 191 </tr>
 192 <tr><td align="left" valign="top"><p>
 193               The units of the distance depends on strategy. In order to change the
 194               default behavior a user has to create a strategy and pass it explicitly
 195               into the algorithm.
 196             </p></td></tr>
 197 </table></div>
 198 <h6>
 199 <a name="geometry.reference.algorithms.densify.densify_3.h5"></a>
 200             <span class="phrase"><a name="geometry.reference.algorithms.densify.densify_3.example"></a></span><a class="link" href="densify_3.html#geometry.reference.algorithms.densify.densify_3.example">Example</a>
 201           </h6>
 202 <p>
 203             Shows how to densify a polygon
 204           </p>
 205 <p>
 206 </p>
 207 <pre class="programlisting"><span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">iostream</span><span class="special">&gt;</span>
 208
 209 <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>
 210 <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>
 211 <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">polygon</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
 212
 213 <span class="keyword">int</span> <span class="identifier">main</span><span class="special">()</span>
 214 <span class="special">{</span>
 215     <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_type</span><span class="special">;</span>
 216     <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_type</span><span class="special">&gt;</span> <span class="identifier">polygon_type</span><span class="special">;</span>
 217
 218     <span class="identifier">polygon_type</span> <span class="identifier">poly</span><span class="special">;</span>
 219     <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>
 220         <span class="string">"POLYGON((0 0,0 10,10 10,10 0,0 0),(1 1,4 1,4 4,1 4,1 1))"</span><span class="special">,</span> <span class="identifier">poly</span><span class="special">);</span>
 221
 222     <span class="identifier">polygon_type</span> <span class="identifier">res</span><span class="special">;</span>
 223
 224     <span class="identifier">boost</span><span class="special">::</span><span class="identifier">geometry</span><span class="special">::</span><span class="identifier">densify</span><span class="special">(</span><span class="identifier">poly</span><span class="special">,</span> <span class="identifier">res</span><span class="special">,</span> <span class="number">6.0</span><span class="special">);</span>
 225
 226     <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="string">"densified: "</span> <span class="special">&lt;&lt;</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">geometry</span><span class="special">::</span><span class="identifier">wkt</span><span class="special">(</span><span class="identifier">res</span><span class="special">)</span> <span class="special">&lt;&lt;</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span>
 227
 228     <span class="keyword">return</span> <span class="number">0</span><span class="special">;</span>
 229 <span class="special">}</span>
 230 </pre>
 231 <p>
 232           </p>
 233 <p>
 234             Output:
 235           </p>
 236 <pre class="programlisting">densified: POLYGON((0 0,0 5,0 10,5 10,10 10,10 5,10 0,5 0,0 0),(1 1,4 1,4 4,1 4,1 1))
 237 </pre>
 238 <h6>
 239 <a name="geometry.reference.algorithms.densify.densify_3.h6"></a>
 240             <span class="phrase"><a name="geometry.reference.algorithms.densify.densify_3.see_also"></a></span><a class="link" href="densify_3.html#geometry.reference.algorithms.densify.densify_3.see_also">See
 241             also</a>
 242           </h6>
 243 <div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
 244                 <a class="link" href="../line_interpolate.html" title="line_interpolate">line_interpolate</a>
 245               </li></ul></div>
 246 </div>
 247 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 248 <td align="left"></td>
 249 <td align="right"><div class="copyright-footer">Copyright &#169; 2009-2019 Barend Gehrels, Bruno Lalande, Mateusz Loskot, Adam
 250       Wulkiewicz, Oracle and/or its affiliates<p>
 251         Distributed under the Boost Software License, Version 1.0. (See accompanying
 252         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>)
 253       </p>
 254 </div></td>
 255 </tr></table>
 256 <hr>
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