52 lines
2.1 KiB
Python
52 lines
2.1 KiB
Python
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"""
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This module houses ctypes interfaces for GDAL objects. The following GDAL
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objects are supported:
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CoordTransform: Used for coordinate transformations from one spatial
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reference system to another.
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Driver: Wraps an OGR data source driver.
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DataSource: Wrapper for the OGR data source object, supports
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OGR-supported data sources.
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Envelope: A ctypes structure for bounding boxes (GDAL library
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not required).
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OGRGeometry: Layer for accessing OGR Geometry objects.
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OGRGeomType: A class for representing the different OGR Geometry
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types (GDAL library not required).
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SpatialReference: Represents OSR Spatial Reference objects.
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The GDAL library will be imported from the system path using the default
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library name for the current OS. The default library path may be overridden
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by setting `GDAL_LIBRARY_PATH` in your settings with the path to the GDAL C
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library on your system.
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GDAL links to a large number of external libraries that consume RAM when
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loaded. Thus, it may desirable to disable GDAL on systems with limited
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RAM resources -- this may be accomplished by setting `GDAL_LIBRARY_PATH`
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to a non-existant file location (e.g., `GDAL_LIBRARY_PATH='/null/path'`;
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setting to None/False/'' will not work as a string must be given).
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"""
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# Attempting to import objects that depend on the GDAL library. The
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# HAS_GDAL flag will be set to True if the library is present on
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# the system.
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try:
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from django.contrib.gis.gdal.driver import Driver
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from django.contrib.gis.gdal.datasource import DataSource
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from django.contrib.gis.gdal.libgdal import gdal_version, gdal_full_version, gdal_release_date
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from django.contrib.gis.gdal.srs import SpatialReference, CoordTransform
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from django.contrib.gis.gdal.geometries import OGRGeometry, GEOJSON
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HAS_GDAL = True
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except:
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HAS_GDAL, GEOJSON = False, False
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# The envelope, error, and geomtype modules do not actually require the
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# GDAL library.
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from django.contrib.gis.gdal.envelope import Envelope
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from django.contrib.gis.gdal.error import check_err, OGRException, OGRIndexError, SRSException
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from django.contrib.gis.gdal.geomtype import OGRGeomType
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