From 1e2d896e336cb9461fb9e4d3ab1e7065f13f2ea0 Mon Sep 17 00:00:00 2001
From: Justin Bronn <jbronn@gmail.com>
Date: Wed, 16 Mar 2011 03:07:30 +0000
Subject: [PATCH] [1.2.X] Fixed #15533 -- Now use 3857 as spherical mercator
 projection instead of deprecated 900913 on platforms that support it.  Thanks
 to cnorthwood for bug report and Christopher Schmidt for OpenLayers
 JavaScript workaround.

Backport of r15845 from trunk.

git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.2.X@15846 bcc190cf-cafb-0310-a4f2-bffc1f526a37
---
 django/contrib/gis/admin/options.py                  | 9 ++++++++-
 django/contrib/gis/templates/gis/admin/openlayers.js | 1 +
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/django/contrib/gis/admin/options.py b/django/contrib/gis/admin/options.py
index 1814933f7b..62c45e7220 100644
--- a/django/contrib/gis/admin/options.py
+++ b/django/contrib/gis/admin/options.py
@@ -113,11 +113,18 @@ class GeoModelAdmin(ModelAdmin):
 
 from django.contrib.gis import gdal
 if gdal.HAS_GDAL:
+    # Use the official spherical mercator projection SRID on versions
+    # of GDAL that support it; otherwise, fallback to 900913
+    if gdal.GDAL_VERSION >= (1, 7):
+        spherical_mercator_srid = 3857
+    else:
+        spherical_mercator_srid = 900913
+
     class OSMGeoAdmin(GeoModelAdmin):
         map_template = 'gis/admin/osm.html'
         extra_js = ['http://openstreetmap.org/openlayers/OpenStreetMap.js']
         num_zoom = 20
-        map_srid = 900913
+        map_srid = spherical_mercator_srid
         max_extent = '-20037508,-20037508,20037508,20037508'
         max_resolution = '156543.0339'
         point_zoom = num_zoom - 6
diff --git a/django/contrib/gis/templates/gis/admin/openlayers.js b/django/contrib/gis/templates/gis/admin/openlayers.js
index 4324693c78..c455bffd58 100644
--- a/django/contrib/gis/templates/gis/admin/openlayers.js
+++ b/django/contrib/gis/templates/gis/admin/openlayers.js
@@ -1,4 +1,5 @@
 {# Author: Justin Bronn, Travis Pinney & Dane Springmeyer #}
+OpenLayers.Projection.addTransform("EPSG:4326", "EPSG:3857", OpenLayers.Layer.SphericalMercator.projectForward);
 {% block vars %}var {{ module }} = {};
 {{ module }}.map = null; {{ module }}.controls = null; {{ module }}.panel = null; {{ module }}.re = new RegExp("^SRID=\d+;(.+)", "i"); {{ module }}.layers = {};
 {{ module }}.modifiable = {{ modifiable|yesno:"true,false" }};