[doc] Note about mulitlinestring in ST_OffsetCurve

Closes #2553

git-svn-id: http://svn.osgeo.org/postgis/trunk@17675 b70326c6-7e19-0410-871a-916f4a2858ee

diff --git a/doc/reference_processing.xml b/doc/reference_processing.xml
index 3b6620bdaf9eafad0b43ce123e73315c7e1c0478..b5ac7aace0236521258dc1247353f02ad1e24c93 100644 (file)
--- a/doc/reference_processing.xml
+++ b/doc/reference_processing.xml
@@ -2261,6 +2261,9 @@ For positive distance the offset will be at the left side of the input line
 and retain the same direction. For a negative distance it'll be at the right
 side and in the opposite direction.
                                </para>
+                               <para>
+Note that output may be a MULTILINESTRING or EMPTY for some jigsaw-shaped input geometries.
+                               </para>
 
                                <para>Performed by the GEOS module.</para>
                                <para>Availability: 2.0</para>