app/django/contrib/gis/utils/srs.py
author Lennard de Rijk <ljvderijk@gmail.com>
Sat, 28 Feb 2009 21:12:20 +0000
changeset 1567 b5589e656ed1
parent 323 ff1a9aa48cfd
permissions -rw-r--r--
Member template in organization is now called Contributor Template. This matches the Organization Application, this way the information is automatically transferred to the new Organization. Note that the template shows raw HTML, we might change the template tag to use |safe for it's input to show the true layout of the template. I've sent an email to SRabbelier about that. Patch by: Lennard de Rijk Reviewed by: to-be-reviewed
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def add_postgis_srs(srs):
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    """
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    This function takes a GDAL SpatialReference system and adds its
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    information to the PostGIS `spatial_ref_sys` table -- enabling
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    spatial transformations with PostGIS.  This is handy for adding
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    spatial reference systems not included by default with PostGIS.  
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    For example, the following adds the so-called "Google Maps Mercator 
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    Projection" (available in GDAL 1.5):
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    >>> add_postgis_srs(SpatialReference(900913))
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    Note: By default, the `auth_name` is set to 'EPSG' -- this should
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    probably be changed.
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    """
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    from django.contrib.gis.models import SpatialRefSys
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    from django.contrib.gis.gdal import SpatialReference
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    if not isinstance(srs, SpatialReference):
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        srs = SpatialReference(srs)
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    if srs.srid is None:
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        raise Exception('Spatial reference requires an SRID to be compatible with PostGIS.')
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    # Creating the spatial_ref_sys model.
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    sr, created = SpatialRefSys.objects.get_or_create(
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        srid=srs.srid, auth_name='EPSG', auth_srid=srs.srid, 
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        srtext=srs.wkt, proj4text=srs.proj4)