Fix ST_Extent/ST_Expand docs to reflect change in behavior of outputting double preci...

git-svn-id: http://svn.osgeo.org/postgis/trunk@5081 b70326c6-7e19-0410-871a-916f4a2858ee

diff --git a/doc/reference_accessor.xml b/doc/reference_accessor.xml
index 70aa4d9d7a69a5e04de989ca18840eba54431a95..ede5458d50a3a77cae2b9eff7fe52ceb1a85fe5a 100644 (file)
--- a/doc/reference_accessor.xml
+++ b/doc/reference_accessor.xml
@@ -297,7 +297,7 @@ SELECT ST_AsEWKT(ST_EndPoint('LINESTRING(1 1 2, 1 2 3, 0 0 5)'));
                  <refnamediv>
                        <refname>ST_Envelope</refname>
 
-                       <refpurpose>Returns a geometry representing the bounding box of the
+                       <refpurpose>Returns a geometry representing the double precision (float8) bounding box of the
                        supplied geometry.</refpurpose>
                  </refnamediv>
 
@@ -314,7 +314,7 @@ SELECT ST_AsEWKT(ST_EndPoint('LINESTRING(1 1 2, 1 2 3, 0 0 5)'));
                  <refsection>
                        <title>Description</title>
 
-                       <para>Returns the float4 minimum bounding box for the supplied geometry, as a geometry.
+                       <para>Returns the float8 minimum bounding box for the supplied geometry, as a geometry.
                        The polygon is defined by the corner points of the bounding box
                        ((<varname>MINX</varname>, <varname>MINY</varname>),
                        (<varname>MINX</varname>, <varname>MAXY</varname>),
@@ -328,17 +328,7 @@ SELECT ST_AsEWKT(ST_EndPoint('LINESTRING(1 1 2, 1 2 3, 0 0 5)'));
                        lower dimension than <varname>POLYGON</varname>, ie.
                        <varname>POINT</varname> or <varname>LINESTRING</varname>.</para>
 
-                       <caution>
-                         <para>In PostGIS, the bounding box of a geometry is represented internally using
-                         <varname>float4</varname>s instead of <varname>float8</varname>s that are used
-                         to store geometries.  The bounding box coordinates are floored, guarenteeing
-                         that the geometry is contained entirely within its bounds.  This has the
-                         advantage that a geometry's bounding box is half the size as the minimum
-                         bounding rectangle, which means significantly faster indexes and general performance.
-                         But it also means that the bounding box is NOT the same as the minimum bounding
-                         rectangle that bounds the geometry.</para>
-                       </caution>
-
+                       <para>Availability: 1.5.0 behavior changed to output double precision instead of float4</para>
                        <para>&sfs_compliant; s2.1.1.1</para>
                        <para>&sqlmm_compliant; SQL-MM 3: 5.1.15</para>
                </refsection>
@@ -375,17 +365,7 @@ SELECT ST_AsText(ST_Envelope('POLYGON((0 0, 0 1, 1.0000000001 1, 1.0000000001 0,
 SELECT Box3D(geom), Box2D(geom), ST_AsText(ST_Envelope(geom)) As envelopewkt
        FROM (SELECT 'POLYGON((0 0, 0 1000012333334.34545678, 1.0000001 1, 1.0000001 0, 0 0))'::geometry As geom) As foo;
 
-box3d
------------------------------------------
-BOX3D(0 0 0,1.0000001 1000012333334.35 0)
-
-box2d
-------------------------------------------
-BOX(0 0,1.00000011920929 1000012382208)
-
-envelopewkt
--------------------------------------------------------------------
-POLYGON((0 0,0 1000012382208,1.00000011920929 1000012382208,1.00000011920929 0,0 0))
+<!-- TODO: Fix examples to reflect new behavior -->
        </programlisting>
          </refsection>
          <refsection>

diff --git a/doc/reference_misc.xml b/doc/reference_misc.xml
index 1d8b063de59ef5588e0642680a8e1e92a6ea7457..13b62bd70b85f97bc973b85effcb361b21125128 100644 (file)
--- a/doc/reference_misc.xml
+++ b/doc/reference_misc.xml
@@ -221,7 +221,7 @@ BOX(-124.659652709961 24.6830825805664,-67.7798080444336 49.0012092590332)
        <refentry id="ST_Expand">
          <refnamediv>
                <refname>ST_Expand</refname>
-               <refpurpose>Returns bounding box expanded in all directions from the bounding box of the input geometry</refpurpose>
+               <refpurpose>Returns bounding box expanded in all directions from the bounding box of the input geometry. Uses double-precision</refpurpose>
          </refnamediv>
 
          <refsynopsisdiv>
@@ -251,7 +251,7 @@ BOX(-124.659652709961 24.6830825805664,-67.7798080444336 49.0012092590332)
 
                <para>This function returns a bounding box expanded in all
                directions from the bounding box of the input geometry, by an
-               amount specified in the second argument. Very useful for
+               amount specified in the second argument. Uses double-precision. Very useful for
                distance() queries, or bounding box queries to add an index filter to the query.</para>
                <para>There are 3 variants of this.  The one that takes a geometry will return a POLYGON geometry representation
                        of the bounding box and is the most commonly used variant.</para>
@@ -268,6 +268,10 @@ BOX(-124.659652709961 24.6830825805664,-67.7798080444336 49.0012092590332)
                <note>
                  <para>Bounding boxes of all geometries are currently 2-d even if they are 3-dimensional geometries.</para>
                </note>
+               
+               <note>
+                       <para>Availability: 1.5.0 behavior changed to output double precision instead of float4 coordinates.</para>
+               </note>
 
          </refsection>
 
@@ -275,6 +279,7 @@ BOX(-124.659652709961 24.6830825805664,-67.7798080444336 49.0012092590332)
                <title>Examples</title>
                <note><para>Examples below use US National Atlas Equal Area (SRID=2163) which is a meter projection</para></note>
                <programlisting>
+               <!-- TODO: fix results of documentation to reflect new behavior -->
 --10 meter expanded box around bbox of a linestring
 SELECT CAST(ST_Expand(ST_GeomFromText('LINESTRING(2312980 110676,2312923 110701,2312892 110714)', 2163),10) As box2d);
                                         st_expand