[postgis-tickets] r14790 - Example of using ST_AsEncodedPath with google maps

[Regina Obe]

Author: robe
Date: 2016-03-19 21:54:14 -0700 (Sat, 19 Mar 2016)
New Revision: 14790

Modified:
   branches/2.2/doc/reference_output.xml
Log:
Example of using ST_AsEncodedPath with google maps

Modified: branches/2.2/doc/reference_output.xml
===================================================================
--- branches/2.2/doc/reference_output.xml	2016-03-19 18:17:04 UTC (rev 14789)
+++ branches/2.2/doc/reference_output.xml	2016-03-20 04:54:14 UTC (rev 14790)
@@ -1258,7 +1258,7 @@
     <refsection>
     <title>Description</title>
 
-    <para>Returns the geometry as an Encoded Polyline.</para>
+    <para>Returns the geometry as an Encoded Polyline.  This is a format very useful if you are using google maps</para>
 
 
     <para>Availability: 2.2.0</para>
@@ -1266,16 +1266,39 @@
 
     <refsection>
     <title>Examples</title>
+<para>Basic </para>
 <programlisting>
-ST_AsEncodedPolyline(GeomFromEWKT('SRID=4326;LINESTRING(-120.2 38.5,-120.95 40.7,-126.453 43.252)'));
+SELECT ST_AsEncodedPolyline(GeomFromEWKT('SRID=4326;LINESTRING(-120.2 38.5,-120.95 40.7,-126.453 43.252)'));
 --result--
 |_p~iF~ps|U_ulLnnqC_mqNvxq`@
 </programlisting>
+
+<para>Use in conjunction with geography linestring and geography segmentize, and put on google maps</para>
+<programlisting>-- the SQL for Boston to San Francisco, segments every 100 KM
+SELECT ST_AsEncodedPolyline(
+	ST_Segmentize(
+		ST_GeogFromText('LINESTRING(-71.0519 42.4935,-122.4483 37.64)'), 
+			100000)::geometry) As encodedFlightPath;</programlisting>
+
+
+<para>javascript will look something like this where $ variable you replace with query result</para>
+<programlisting><![CDATA[
+<script type="text/javascript" src="http://maps.googleapis.com/maps/api/js?libraries=geometry"></script>
+<script type="text/javascript">
+     flightPath = new google.maps.Polyline({
+            path:  google.maps.geometry.encoding.decodePath("$encodedFlightPath"),
+            map: map,
+            strokeColor: '#0000CC',
+            strokeOpacity: 1.0,
+            strokeWeight: 4
+        });
+</script>
+]]></programlisting>
 </refsection>
     <!-- Optionally add a "See Also" section -->
     <refsection>
     <title>See Also</title>
-    <para><xref linkend="ST_LineFromEncodedPolyline" /></para>
+    <para><xref linkend="ST_LineFromEncodedPolyline" />, <xref linked="ST_Segmentize" /></para>
     </refsection>
 </refentry>
   </sect1>