classogrpolygon.html

gdal库的学习文档

<a class="anchor" name="bc23b7c96a4825d5b8b121219f31354a"></a><!-- doxytag: member="OGRPolygon::get_Area" ref="bc23b7c96a4825d5b8b121219f31354a" args="() const" -->
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          <td class="memname">double OGRPolygon::get_Area           </td>
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<p>
Compute area of polygon.<p>
The area is computed as the area of the outer ring less the area of all internal rings.<p>
<dl class="return" compact><dt><b>Returns:</b></dt><dd>computed area. </dd></dl>

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Implements <a class="el" href="classOGRSurface.html#f6d00ea56d219c4456163a4c11eafc7c">OGRSurface</a>.
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<a class="anchor" name="d12bc18f6f0f7c0209c26f5e4cd9eadc"></a><!-- doxytag: member="OGRPolygon::Centroid" ref="d12bc18f6f0f7c0209c26f5e4cd9eadc" args="(OGRPoint *poPoint) const " -->
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          <td class="memname">int OGRPolygon::Centroid           </td>
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          <td class="paramtype"><a class="el" href="classOGRPoint.html">OGRPoint</a> *&nbsp;</td>
          <td class="paramname"> <em>poPoint</em>          </td>
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<p>
Compute the polygon centroid.<p>
The centroid location is applied to the passed in <a class="el" href="classOGRPoint.html">OGRPoint</a> object.<p>
<dl class="return" compact><dt><b>Returns:</b></dt><dd>OGRERR_NONE on success or OGRERR_FAILURE on error. </dd></dl>

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Implements <a class="el" href="classOGRSurface.html#3f662a2a483477b83224e02be6fde080">OGRSurface</a>.
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<a class="anchor" name="76e64f21cd31a6256cc425a6b5639069"></a><!-- doxytag: member="OGRPolygon::PointOnSurface" ref="76e64f21cd31a6256cc425a6b5639069" args="(OGRPoint *poPoint) const " -->
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          <td class="memname">int OGRPolygon::PointOnSurface           </td>
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          <td class="paramtype"><a class="el" href="classOGRPoint.html">OGRPoint</a> *&nbsp;</td>
          <td class="paramname"> <em>poPoint</em>          </td>
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This method relates to the SFCOM ISurface::get_PointOnSurface() method.<p>
NOTE: Only implemented when GEOS included in build.<p>
<dl compact><dt><b>Parameters:</b></dt><dd>
  <table border="0" cellspacing="2" cellpadding="0">
    <tr><td valign="top"></td><td valign="top"><em>poPoint</em>&nbsp;</td><td>point to be set with an internal point.</td></tr>
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<dl class="return" compact><dt><b>Returns:</b></dt><dd>OGRERR_NONE if it succeeds or OGRERR_FAILURE otherwise. </dd></dl>

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Implements <a class="el" href="classOGRSurface.html#1d28c548d1ceba9841597c5a37356226">OGRSurface</a>.
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<a class="anchor" name="13e26001d05019fedad787c8e8bc92bc"></a><!-- doxytag: member="OGRPolygon::WkbSize" ref="13e26001d05019fedad787c8e8bc92bc" args="() const" -->
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          <td class="memname">int OGRPolygon::WkbSize           </td>
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Returns size of related binary representation.<p>
This method returns the exact number of bytes required to hold the well known binary representation of this geometry object. Its computation may be slightly expensive for complex geometries.<p>
This method relates to the SFCOM IWks::WkbSize() method.<p>
This method is the same as the C function <a class="el" href="ogr__api_8h.html#5f7035a933b957a9d453184c154c237c">OGR_G_WkbSize()</a>.<p>
<dl class="return" compact><dt><b>Returns:</b></dt><dd>size of binary representation in bytes. </dd></dl>

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Implements <a class="el" href="classOGRGeometry.html#68215bd90d675b7627a798b162c54ab1">OGRGeometry</a>.
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<a class="anchor" name="46b833f19bf35fcea113233310a245ce"></a><!-- doxytag: member="OGRPolygon::importFromWkb" ref="46b833f19bf35fcea113233310a245ce" args="(unsigned char *, int=-1)" -->
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          <td class="memname">OGRErr OGRPolygon::importFromWkb           </td>
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          <td class="paramtype">unsigned char *&nbsp;</td>
          <td class="paramname"> <em>pabyData</em>, </td>
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          <td class="paramtype">int&nbsp;</td>
          <td class="paramname"> <em>nSize</em> = <code>-1</code></td><td>&nbsp;</td>
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<p>
Assign geometry from well known binary data.<p>
The object must have already been instantiated as the correct derived type of geometry object to match the binaries type. This method is used by the <a class="el" href="classOGRGeometryFactory.html">OGRGeometryFactory</a> class, but not normally called by application code.<p>
This method relates to the SFCOM IWks::ImportFromWKB() method.<p>
This method is the same as the C function <a class="el" href="ogr__api_8h.html#fa5a9173aa3b10a4db09ed696a92ba4a">OGR_G_ImportFromWkb()</a>.<p>
<dl compact><dt><b>Parameters:</b></dt><dd>
  <table border="0" cellspacing="2" cellpadding="0">
    <tr><td valign="top"></td><td valign="top"><em>pabyData</em>&nbsp;</td><td>the binary input data. </td></tr>
    <tr><td valign="top"></td><td valign="top"><em>nSize</em>&nbsp;</td><td>the size of pabyData in bytes, or zero if not known.</td></tr>
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<dl class="return" compact><dt><b>Returns:</b></dt><dd>OGRERR_NONE if all goes well, otherwise any of OGRERR_NOT_ENOUGH_DATA, OGRERR_UNSUPPORTED_GEOMETRY_TYPE, or OGRERR_CORRUPT_DATA may be returned. </dd></dl>

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Implements <a class="el" href="classOGRGeometry.html#b2c6583c2b7c3e526dcfe54a61470c1f">OGRGeometry</a>.
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<a class="anchor" name="454605f77cb9e17c290272321cac161f"></a><!-- doxytag: member="OGRPolygon::exportToWkb" ref="454605f77cb9e17c290272321cac161f" args="(OGRwkbByteOrder, unsigned char *) const" -->
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          <td class="memname">OGRErr OGRPolygon::exportToWkb           </td>
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          <td class="paramtype">OGRwkbByteOrder&nbsp;</td>
          <td class="paramname"> <em>eByteOrder</em>, </td>
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          <td class="paramtype">unsigned char *&nbsp;</td>
          <td class="paramname"> <em>pabyData</em></td><td>&nbsp;</td>
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Convert a geometry into well known binary format.<p>
This method relates to the SFCOM IWks::ExportToWKB() method.<p>
This method is the same as the C function <a class="el" href="ogr__api_8h.html#d5c94ae76c09774dba8725c24daeefd6">OGR_G_ExportToWkb()</a>.<p>
<dl compact><dt><b>Parameters:</b></dt><dd>
  <table border="0" cellspacing="2" cellpadding="0">
    <tr><td valign="top"></td><td valign="top"><em>eByteOrder</em>&nbsp;</td><td>One of wkbXDR or wkbNDR indicating MSB or LSB byte order respectively. </td></tr>
    <tr><td valign="top"></td><td valign="top"><em>pabyData</em>&nbsp;</td><td>a buffer into which the binary representation is written. This buffer must be at least <a class="el" href="classOGRGeometry.html#68215bd90d675b7627a798b162c54ab1">OGRGeometry::WkbSize()</a> byte in size.</td></tr>
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<dl class="return" compact><dt><b>Returns:</b></dt><dd>Currently OGRERR_NONE is always returned. </dd></dl>

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Implements <a class="el" href="classOGRGeometry.html#6fe8947602669a35136e107cd45b084d">OGRGeometry</a>.
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<a class="anchor" name="84d3b6e0ee2b098528a537bb874b4856"></a><!-- doxytag: member="OGRPolygon::importFromWkt" ref="84d3b6e0ee2b098528a537bb874b4856" args="(char **)" -->
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          <td class="paramtype">char **&nbsp;</td>
          <td class="paramname"> <em>ppszInput</em>          </td>
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<p>
Assign geometry from well known text data.<p>
The object must have already been instantiated as the correct derived type of geometry object to match the text type. This method is used by the <a class="el" href="classOGRGeometryFactory.html">OGRGeometryFactory</a> class, but not normally called by application code.<p>
This method relates to the SFCOM IWks::ImportFromWKT() method.<p>
This method is the same as the C function <a class="el" href="ogr__api_8h.html#4286ba243fb05a831a49f52aabcbc6f8">OGR_G_ImportFromWkt()</a>.<p>
<dl compact><dt><b>Parameters:</b></dt><dd>
  <table border="0" cellspacing="2" cellpadding="0">
    <tr><td valign="top"></td><td valign="top"><em>ppszInput</em>&nbsp;</td><td>pointer to a pointer to the source text. The pointer is updated to pointer after the consumed text.</td></tr>
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<dl class="return" compact><dt><b>Returns:</b></dt><dd>OGRERR_NONE if all goes well, otherwise any of OGRERR_NOT_ENOUGH_DATA, OGRERR_UNSUPPORTED_GEOMETRY_TYPE, or OGRERR_CORRUPT_DATA may be returned. </dd></dl>

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Implements <a class="el" href="classOGRGeometry.html#30561a301d44b1f90393ea4a78a5b0a5">OGRGeometry</a>.
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<a class="anchor" name="08dfe388ceeaa3e88aa7f8fa28b00b95"></a><!-- doxytag: member="OGRPolygon::exportToWkt" ref="08dfe388ceeaa3e88aa7f8fa28b00b95" args="(char **ppszDstText) const" -->
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          <td class="paramtype">char **&nbsp;</td>
          <td class="paramname"> <em>ppszDstText</em>          </td>
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<p>
Convert a geometry into well known text format.<p>
This method relates to the SFCOM IWks::ExportToWKT() method.<p>
This method is the same as the C function <a class="el" href="ogr__api_8h.html#3bc9310302e2dbfaab1690de9e2fd2fb">OGR_G_ExportToWkt()</a>.<p>
<dl compact><dt><b>Parameters:</b></dt><dd>
  <table border="0" cellspacing="2" cellpadding="0">
    <tr><td valign="top"></td><td valign="top"><em>ppszDstText</em>&nbsp;</td><td>a text buffer is allocated by the program, and assigned to the passed pointer.</td></tr>
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<dl class="return" compact><dt><b>Returns:</b></dt><dd>Currently OGRERR_NONE is always returned. </dd></dl>

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Implements <a class="el" href="classOGRGeometry.html#71184265101d21cffa5c50ee79afdd61">OGRGeometry</a>.
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<a class="anchor" name="28e379c5f9e8118f759455fbe1279640"></a><!-- doxytag: member="OGRPolygon::getDimension" ref="28e379c5f9e8118f759455fbe1279640" args="() const" -->
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