Document precision in EncodedPolyline.

Closes #3631

git-svn-id: http://svn.osgeo.org/postgis/trunk@16651 b70326c6-7e19-0410-871a-916f4a2858ee

diff --git a/doc/reference_constructor.xml b/doc/reference_constructor.xml
index e2f2a01bf5db1d9ef9d034b62348c0bada0a696e..e95ca01ea9fb49cb6d4626132d3bcb9ef107791e 100644 (file)
--- a/doc/reference_constructor.xml
+++ b/doc/reference_constructor.xml
@@ -1071,6 +1071,8 @@ SELECT
     <title>Description</title>
 
     <para>Creates a LineString from an Encoded Polyline string.</para>
+               <para>Optional <varname>precision</varname> specifies how many decimal places will be preserved in Encoded Polyline. Value should be the same on encoding and decoding, or coordinates will be incorrect.</para>
+
     <para>See http://developers.google.com/maps/documentation/utilities/polylinealgorithm</para>
     <para>Availability: 2.2.0</para>
     </refsection>
@@ -1079,10 +1081,16 @@ SELECT
     <title>Examples</title>
 
     <programlisting>
---Create a line string from a polyline
+-- Create a line string from a polyline
 SELECT ST_AsEWKT(ST_LineFromEncodedPolyline('_p~iF~ps|U_ulLnnqC_mqNvxq`@'));
---result--
-LINESTRING(-120.2 38.5,-120.95 40.7,-126.453 43.252)
+-- result --
+SRID=4326;LINESTRING(-120.2 38.5,-120.95 40.7,-126.453 43.252)
+
+-- Select different precision that was used for polyline encoding
+SELECT ST_AsEWKT(ST_LineFromEncodedPolyline('_p~iF~ps|U_ulLnnqC_mqNvxq`@',6));
+-- result --
+SRID=4326;LINESTRING(-12.02 3.85,-12.095 4.07,-12.6453 4.3252)
+
     </programlisting>
     </refsection>
 

diff --git a/doc/reference_output.xml b/doc/reference_output.xml
index a9c7f747e0137004de729a1a26ba69de11627c13..92204b9734874a24aa407d16e670454a90bb6a90 100644 (file)
--- a/doc/reference_output.xml
+++ b/doc/reference_output.xml
@@ -126,8 +126,8 @@
                <refsection>
                <title>Description</title>
 
-               <para>Returns the geometry as an Encoded Polyline.  This is a format very useful if you are using google maps</para>
-
+               <para>Returns the geometry as an Encoded Polyline. This format is used by Google Maps with precision=5 and by Open Source Routing Machine with precision=5 and 6.</para>
+               <para>Optional <varname>precision</varname> specifies how many decimal places will be preserved in Encoded Polyline. Value should be the same on encoding and decoding, or coordinates will be incorrect.</para>
 
                <para>Availability: 2.2.0</para>
                </refsection>