Enhance documentation for ST_ChangeEdgeGeom

git-svn-id: http://svn.osgeo.org/postgis/trunk@9234 b70326c6-7e19-0410-871a-916f4a2858ee

diff --git a/doc/extras_topology.xml b/doc/extras_topology.xml
index 229b2ff2b96aeda888292fcc14c494d60de13b63..eac842fa6048d6c51f8bcd86f7db19a0fa5f75b0 100644 (file)
--- a/doc/extras_topology.xml
+++ b/doc/extras_topology.xml
@@ -1069,8 +1069,9 @@ name is invalid then an error is thrown.
                        <refnamediv>
                                <refname>ST_ChangeEdgeGeom</refname>
                        
-                               <refpurpose>Changes the linestring that define the specified edge. Will raise an error if the start and end points are not the same as the original or the new linestring
-                               crosses an existing edge (not at end points) or new linestring is not simple.</refpurpose>
+                               <refpurpose>
+Changes the shape of an edge without affecting the topology structure.
+                               </refpurpose>
                        </refnamediv>
                
                        <refsynopsisdiv>
@@ -1087,16 +1088,33 @@ name is invalid then an error is thrown.
                        <refsection>
                 <title>Description</title>
             
-                <para>Changes the linestring that defines the specified edge. Will raise an error if the start and end points are not the same as the original or the new linestring
-                               crosses an existing edge (except at end points) or intersects another edge.</para>
-                <para>If any arguments are null, the given edge does not exist in the <varname>node</varname> table of the topology schema) ,
-                    the <varname>acurve</varname> is not a <varname>LINESTRING</varname>, the <varname>anode</varname> and <varname>anothernode</varname> are not the start 
-                    and endpoints of <varname>acurve</varname> then an error is thrown.</para>
+                <para>
+Changes the shape of an edge without affecting the topology structure.
+               </para>
+                <para>
+If any arguments are null, the given edge does not exist in
+the <varname>node</varname> table of the topology schema, the
+<varname>acurve</varname> is not a <varname>LINESTRING</varname>, the
+<varname>anode</varname> and <varname>anothernode</varname> are not the
+start and endpoints of <varname>acurve</varname> or the modification would
+change the underlying topology then an error is thrown.
+               </para>
                 <para>If the spatial reference system (srid) of the <varname>acurve</varname> geometry is not the same as the topology an exception is thrown.</para>
                 <para>If the new <varname>acurve</varname> is not simple, then an error is thrown.</para>
+
+                <para>
+If moving the edge from old to new position would hit an obstacle then
+an error is thrown.
+               </para>
              
                 <!-- use this format if new function -->
                 <para>Availability: 1.1.0</para>
+
+                <!-- use this format if not a new function but functionality enhanced -->
+                <para>
+       Enhanced: 2.0.0 adds topological consistency enforcement
+               </para>
+
                 <para>&sqlmm_compliant; SQL-MM: Topo-Geo and Topo-Net 3: Routine Details X.3.6</para>
                        </refsection>