From f32421c617144bb9a75e8aac27eeac6e87c9205c Mon Sep 17 00:00:00 2001
From: Regina Obe <lr@pcorp.us>
Date: Tue, 10 Nov 2009 12:08:21 +0000
Subject: [PATCH] add ST_Intersects proto for geography

git-svn-id: http://svn.osgeo.org/postgis/trunk@4771 b70326c6-7e19-0410-871a-916f4a2858ee
---
 doc/reference.xml | 43 ++++++++++++++++++++++++++++++++++++-------
 1 file changed, 36 insertions(+), 7 deletions(-)

diff --git a/doc/reference.xml b/doc/reference.xml
index 2b0db66b6..1836ee950 100644
--- a/doc/reference.xml
+++ b/doc/reference.xml
@@ -10853,8 +10853,9 @@ SELECT ST_Equals(ST_Reverse(ST_GeomFromText('LINESTRING(0 0, 10 10)')),
 		<refnamediv>
 			<refname>ST_Intersects</refname>
 
-			<refpurpose>Returns TRUE if the Geometries "spatially
+			<refpurpose>Returns TRUE if the Geometries/Geography "spatially
 			intersect" - (share any portion of space) and FALSE if they don't (they are Disjoint).
+			For geography -- tolerance is 0.00001 meters (so any points that close are considered to intersect)
 			</refpurpose>
 		</refnamediv>
 		<refsynopsisdiv>
@@ -10863,11 +10864,22 @@ SELECT ST_Equals(ST_Reverse(ST_GeomFromText('LINESTRING(0 0, 10 10)')),
 					<funcdef>boolean <function>ST_Intersects</function></funcdef>
 					<paramdef>
 						<type>geometry</type>
-						<parameter>A</parameter>
+						<parameter>geomA</parameter>
 					</paramdef>
 					<paramdef>
 						<type>geometry</type>
-						<parameter>B</parameter>
+						<parameter>geomB</parameter>
+					</paramdef>
+				</funcprototype>
+				<funcprototype>
+					<funcdef>boolean <function>ST_Intersects</function></funcdef>
+					<paramdef>
+						<type>geography</type>
+						<parameter>geogA</parameter>
+					</paramdef>
+					<paramdef>
+						<type>geography</type>
+						<parameter>geogB</parameter>
 					</paramdef>
 				</funcprototype>
 			</funcsynopsis>
@@ -10879,15 +10891,20 @@ SELECT ST_Equals(ST_Reverse(ST_GeomFromText('LINESTRING(0 0, 10 10)')),
 				Disjoint implies false for spatial intersection.</para>
 
 	  <important>
-		<para>Do not call with a <varname>GEOMETRYCOLLECTION</varname> as an argument</para>
+		<para>Do not call with a <varname>GEOMETRYCOLLECTION</varname> as an argument for geometry version.  The geography
+			version supports GEOMETRYCOLLECTION since its a thin wrapper around distance implementation.</para>
 	  </important>
 
-			<para>Performed by the GEOS module</para>
+			<para>Performed by the GEOS module (for geometry), geography is native</para>
+			<para>Availability: 1.5 support for geography was introduced.</para>
 			<note>
 			  <para>This function call will automatically include a bounding box
 			  comparison that will make use of any indexes that are available on the
 			  geometries.</para>
-
+			</note>
+			<note>
+			  <para>For geography, this function has a distance tolerance of about 0.00001 meters and uses the sphere rather
+			  	than spheroid calculation.</para>
 			</note>
 			<note>
 			  <para>NOTE: this is the "allowable" version that returns a
@@ -10909,7 +10926,7 @@ SELECT ST_Equals(ST_Reverse(ST_GeomFromText('LINESTRING(0 0, 10 10)')),
 			SQL-MM 3: 5.1.27</para>
 		</refsection>
 		<refsection>
-		<title>Examples</title>
+		<title>Geometry Examples</title>
 <programlisting>SELECT ST_Intersects('POINT(0 0)'::geometry, 'LINESTRING ( 2 0, 0 2 )'::geometry);
  st_intersects
 ---------------
@@ -10921,6 +10938,18 @@ SELECT ST_Intersects('POINT(0 0)'::geometry, 'LINESTRING ( 0 0, 0 2 )'::geometry
  t
 (1 row)
 		</programlisting>
+		</refsection>
+		<refsection>
+		<title>Geography Examples</title>
+<programlisting>SELECT ST_Intersects(
+		ST_GeographyFromText('SRID=4326;LINESTRING(-43.23456 72.4567,-43.23456 72.4568)'),
+		ST_GeographyFromText('SRID=4326;POINT(-43.23456 72.4567772)')
+		);
+
+ st_intersects
+---------------
+t
+</programlisting>
 		</refsection>
 		<refsection>
 			<title>See Also</title>
-- 
2.50.1