BaseSpatialField.srid Sets the SRID [2] (Spatial Reference System Identity) of the geometry field to the given value. Defaults to 4326 (also known as WGS84, units are in degrees of longitude and latitude).

class Extent(geo_field) Availability: PostGIS, Oracle, SpatiaLite Returns the extent of all geo_field in the QuerySet as a four-tuple, comprising the lower left coordinate and the upper right coordinate. Example: >>> qs = City.objects.filter(name__in=('Houston', 'Dallas')).aggregate(Extent('poly')) >>> print(qs['poly__extent']) (-96.8016128540039, 29.7633724212646, -95.3631439208984, 32.782058715820)

class OSMGeoAdmin A subclass of GeoModelAdmin that uses a spherical mercator projection with OpenStreetMap street data tiles. See the OSMGeoAdmin introduction in the tutorial for a usage example.

class Collect(geo_field) Availability: PostGIS, SpatiaLite Returns a GEOMETRYCOLLECTION or a MULTI geometry object from the geometry column. This is analogous to a simplified version of the Union aggregate, except it can be several orders of magnitude faster than performing a union because it simply rolls up geometries into a collection or multi object, not caring about dissolving boundaries.

BaseSpatialField.spatial_index Defaults to True. Creates a spatial index for the given geometry field. Note This is different from the db_index field option because spatial indexes are created in a different manner than regular database indexes. Specifically, spatial indexes are typically created using a variant of the R-Tree, while regular database indexes typically use B-Trees.

map_height Height of the map, in pixels. Defaults to 400.

modifiable Defaults to True. When set to False, disables editing of existing geometry fields in the admin. Note This is different from adding the geometry field to readonly_fields, which will only display the WKT of the geometry. Setting modifiable=False, actually displays the geometry in a map, but disables the ability to edit its vertices.

map_template Override the template used to generate the JavaScript slippy map. Default is 'gis/admin/openlayers.html'.

default_zoom The default zoom level to use. Defaults to 18.

map_width Width of the map, in pixels. Defaults to 600.