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<title>GEOS: geos::simplify::TopologyPreservingSimplifier Class Reference</title>
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<li><a class="el" href="namespacegeos.html">geos</a> </li>
<li><b>simplify</b> </li>
<li><a class="el" href="classgeos_1_1simplify_1_1TopologyPreservingSimplifier.html">geos::simplify::TopologyPreservingSimplifier</a> </li>
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<a href="#pub-methods">Public Member Functions</a> |
<a href="#pub-static-methods">Static Public Member Functions</a> </div>
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<h1>geos::simplify::TopologyPreservingSimplifier Class Reference</h1> </div>
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<p>Simplifies a geometry, ensuring that the result is a valid geometry having the same dimension and number of components as the input.
<a href="#_details">More...</a></p>
<p><code>#include <<a class="el" href="TopologyPreservingSimplifier_8h_source.html">TopologyPreservingSimplifier.h</a>></code></p>
<p><a href="classgeos_1_1simplify_1_1TopologyPreservingSimplifier-members.html">List of all members.</a></p>
<table class="memberdecls">
<tr><td colspan="2"><h2><a name="pub-methods"></a>
Public Member Functions</h2></td></tr>
<tr><td class="memItemLeft" align="right" valign="top"><a class="anchor" id="ac49755ec6f280635d1562a38567d74d4"></a><!-- doxytag: member="geos::simplify::TopologyPreservingSimplifier::TopologyPreservingSimplifier" ref="ac49755ec6f280635d1562a38567d74d4" args="(const geom::Geometry *geom)" -->
</td><td class="memItemRight" valign="bottom"><b>TopologyPreservingSimplifier</b> (const <a class="el" href="classgeos_1_1geom_1_1Geometry.html">geom::Geometry</a> *geom)</td></tr>
<tr><td class="memItemLeft" align="right" valign="top">void </td><td class="memItemRight" valign="bottom"><a class="el" href="classgeos_1_1simplify_1_1TopologyPreservingSimplifier.html#a9e387d4f27f7bf6284368484b3b5f23c">setDistanceTolerance</a> (double tolerance)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Sets the distance tolerance for the simplification. <a href="#a9e387d4f27f7bf6284368484b3b5f23c"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top"><a class="anchor" id="ad11f7e4ba2c6c70dfdaae2acf0188b10"></a><!-- doxytag: member="geos::simplify::TopologyPreservingSimplifier::getResultGeometry" ref="ad11f7e4ba2c6c70dfdaae2acf0188b10" args="()" -->
std::auto_ptr< <a class="el" href="classgeos_1_1geom_1_1Geometry.html">geom::Geometry</a> > </td><td class="memItemRight" valign="bottom"><b>getResultGeometry</b> ()</td></tr>
<tr><td colspan="2"><h2><a name="pub-static-methods"></a>
Static Public Member Functions</h2></td></tr>
<tr><td class="memItemLeft" align="right" valign="top"><a class="anchor" id="a09fcd20d002c57ba3db2ef41894b1313"></a><!-- doxytag: member="geos::simplify::TopologyPreservingSimplifier::simplify" ref="a09fcd20d002c57ba3db2ef41894b1313" args="(const geom::Geometry *geom, double tolerance)" -->
static std::auto_ptr<br class="typebreak"/>
< <a class="el" href="classgeos_1_1geom_1_1Geometry.html">geom::Geometry</a> > </td><td class="memItemRight" valign="bottom"><b>simplify</b> (const <a class="el" href="classgeos_1_1geom_1_1Geometry.html">geom::Geometry</a> *geom, double tolerance)</td></tr>
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<hr/><a name="_details"></a><h2>Detailed Description</h2>
<p>Simplifies a geometry, ensuring that the result is a valid geometry having the same dimension and number of components as the input. </p>
<p>The simplification uses a maximum distance difference algorithm similar to the one used in the Douglas-Peucker algorithm.</p>
<p>In particular, if the input is an areal geometry ( Polygon or MultiPolygon )</p>
<ul>
<li>The result has the same number of shells and holes (rings) as the input, in the same order</li>
<li>The result rings touch at <b>no more</b> than the number of touching point in the input (although they may touch at fewer points) </li>
</ul>
<hr/><h2>Member Function Documentation</h2>
<a class="anchor" id="a9e387d4f27f7bf6284368484b3b5f23c"></a><!-- doxytag: member="geos::simplify::TopologyPreservingSimplifier::setDistanceTolerance" ref="a9e387d4f27f7bf6284368484b3b5f23c" args="(double tolerance)" -->
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<td class="memname">void geos::simplify::TopologyPreservingSimplifier::setDistanceTolerance </td>
<td>(</td>
<td class="paramtype">double </td>
<td class="paramname"> <em>tolerance</em></td>
<td> ) </td>
<td></td>
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<p>Sets the distance tolerance for the simplification. </p>
<p>All vertices in the simplified geometry will be within this distance of the original geometry. The tolerance value must be non-negative. A tolerance value of zero is effectively a no-op.</p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>distanceTolerance</em> </td><td>the approximation tolerance to use </td></tr>
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<hr/>The documentation for this class was generated from the following file:<ul>
<li><a class="el" href="TopologyPreservingSimplifier_8h_source.html">TopologyPreservingSimplifier.h</a></li>
</ul>
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