</listitem>
</varlistentry>
- <varlistentry>
- <term>ST_Simplify(geometry, tolerance)</term>
-
- <listitem>
- <para>Returns a "simplified" version of the given geometry using
- the Douglas-Peuker algorithm. Will actually do something only with
- (multi)lines and (multi)polygons but you can safely call it with
- any kind of geometry. Since simplification occurs on a
- object-by-object basis you can also feed a GeometryCollection to
- this function. Note that returned geometry might loose its
- simplicity (see <xref linkend="ST_IsSimple" />)</para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term>ST_SimplifyPreserveTopology(geometry, tolerance)</term>
-
- <listitem>
- <para>Returns a "simplified" version of the given geometry using
- the Douglas-Peuker algorithm. Will avoid creating derived
- geometries (polygons in particular) that are invalid.</para>
- </listitem>
- </varlistentry>
-
<varlistentry>
<term>ST_SnapToGrid(geometry, originX, originY, sizeX, sizeY)</term>
<para><xref linkend="ST_Dump" /></para>
</refsection>
</refentry>
+
+ <refentry id="ST_Simplify">
+ <refnamediv>
+ <refname>ST_Simplify</refname>
+ <refpurpose>Returns a "simplified" version of the given geometry using
+ the Douglas-Peuker algorithm.</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <funcsynopsis>
+ <funcprototype>
+ <funcdef>geometry <function>ST_Simplify</function></funcdef>
+ <paramdef><type>geometry</type> <parameter>geomA</parameter></paramdef>
+ <paramdef><type>float</type> <parameter>tolerance</parameter></paramdef>
+ </funcprototype>
+ </funcsynopsis>
+ </refsynopsisdiv>
+
+ <refsection>
+ <title>Description</title>
+ <para>Returns a "simplified" version of the given geometry using
+ the Douglas-Peuker algorithm. Will actually do something only with
+ (multi)lines and (multi)polygons but you can safely call it with
+ any kind of geometry. Since simplification occurs on a
+ object-by-object basis you can also feed a GeometryCollection to
+ this function.</para>
+
+ <note><para>Note that returned geometry might loose its
+ simplicity (see <xref linkend="ST_IsSimple" />)</para></note>
+ <note><para>Note topology may not be preserved and may result in invalid geometries. Use (see <xref linkend="ST_SimplifyPreserveTopology" />) to preserve topology.</para></note>
+
+ <para>Performed by the GEOS module.</para>
+ <para>Availability: 1.2.2</para>
+ </refsection>
+
+ <refsection>
+ <title>Examples</title>
+ <para>Forthcoming</para>
+ <programlisting>
+ <!-- TODO: Need examples -->
+
+ </programlisting>
+ </refsection>
+ <refsection>
+ <title>See Also</title>
+ <para><xref linkend="ST_SimplifyPreserveTopology" /></para>
+ </refsection>
+ </refentry>
+
+ <refentry id="ST_SimplifyPreserveTopology">
+ <refnamediv>
+ <refname>ST_SimplifyPreserveTopology</refname>
+ <refpurpose>Returns a "simplified" version of the given geometry using
+ the Douglas-Peuker algorithm. Will avoid creating derived
+ geometries (polygons in particular) that are invalid.</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <funcsynopsis>
+ <funcprototype>
+ <funcdef>geometry <function>ST_SimplifyPreserveTopology</function></funcdef>
+ <paramdef><type>geometry</type> <parameter>geomA</parameter></paramdef>
+ <paramdef><type>float</type> <parameter>tolerance</parameter></paramdef>
+ </funcprototype>
+ </funcsynopsis>
+ </refsynopsisdiv>
+
+ <refsection>
+ <title>Description</title>
+ <para>Returns a "simplified" version of the given geometry using
+ the Douglas-Peuker algorithm. Will avoid creating derived
+ geometries (polygons in particular) that are invalid. Will actually do something only with
+ (multi)lines and (multi)polygons but you can safely call it with
+ any kind of geometry. Since simplification occurs on a
+ object-by-object basis you can also feed a GeometryCollection to
+ this function.</para>
+
+ <para>Performed by the GEOS module.</para>
+ <note><para>Requires GEOS 3.0.0+</para></note>
+ <para>Availability: 1.3.3</para>
+ </refsection>
+
+ <refsection>
+ <title>Examples</title>
+ <para>Forthcoming</para>
+ <programlisting>
+ <!-- TODO: Need examples -->
+ </programlisting>
+ </refsection>
+ <refsection>
+ <title>See Also</title>
+ <para><xref linkend="ST_Simplify" /></para>
+ </refsection>
+ </refentry>
+
+
<refentry id="ST_Union">
<refnamediv>
<refname>ST_Union</refname>