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-rw-r--r--webapp/django/contrib/gis/gdal/feature.py115
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diff --git a/webapp/django/contrib/gis/gdal/feature.py b/webapp/django/contrib/gis/gdal/feature.py
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+# The GDAL C library, OGR exception, and the Field object
+from django.contrib.gis.gdal.error import OGRException, OGRIndexError
+from django.contrib.gis.gdal.field import Field
+from django.contrib.gis.gdal.geometries import OGRGeometry, OGRGeomType
+from django.contrib.gis.gdal.srs import SpatialReference
+
+# ctypes function prototypes
+from django.contrib.gis.gdal.prototypes.ds import \
+ destroy_feature, feature_equal, get_fd_geom_type, get_feat_geom_ref, \
+ get_feat_name, get_feat_field_count, get_fid, get_field_defn, \
+ get_field_index, get_field_name
+from django.contrib.gis.gdal.prototypes.geom import clone_geom, get_geom_srs
+from django.contrib.gis.gdal.prototypes.srs import clone_srs
+
+# For more information, see the OGR C API source code:
+# http://www.gdal.org/ogr/ogr__api_8h.html
+#
+# The OGR_F_* routines are relevant here.
+class Feature(object):
+ "A class that wraps an OGR Feature, needs to be instantiated from a Layer object."
+
+ #### Python 'magic' routines ####
+ def __init__(self, feat, fdefn):
+ "Initializes on the pointers for the feature and the layer definition."
+ self._ptr = None # Initially NULL
+ if not feat or not fdefn:
+ raise OGRException('Cannot create OGR Feature, invalid pointer given.')
+ self._ptr = feat
+ self._fdefn = fdefn
+
+ def __del__(self):
+ "Releases a reference to this object."
+ if self._ptr: destroy_feature(self._ptr)
+
+ def __getitem__(self, index):
+ """
+ Gets the Field object at the specified index, which may be either
+ an integer or the Field's string label. Note that the Field object
+ is not the field's _value_ -- use the `get` method instead to
+ retrieve the value (e.g. an integer) instead of a Field instance.
+ """
+ if isinstance(index, basestring):
+ i = self.index(index)
+ else:
+ if index < 0 or index > self.num_fields:
+ raise OGRIndexError('index out of range')
+ i = index
+ return Field(self._ptr, i)
+
+ def __iter__(self):
+ "Iterates over each field in the Feature."
+ for i in xrange(self.num_fields):
+ yield self[i]
+
+ def __len__(self):
+ "Returns the count of fields in this feature."
+ return self.num_fields
+
+ def __str__(self):
+ "The string name of the feature."
+ return 'Feature FID %d in Layer<%s>' % (self.fid, self.layer_name)
+
+ def __eq__(self, other):
+ "Does equivalence testing on the features."
+ return bool(feature_equal(self._ptr, other._ptr))
+
+ #### Feature Properties ####
+ @property
+ def fid(self):
+ "Returns the feature identifier."
+ return get_fid(self._ptr)
+
+ @property
+ def layer_name(self):
+ "Returns the name of the layer for the feature."
+ return get_feat_name(self._fdefn)
+
+ @property
+ def num_fields(self):
+ "Returns the number of fields in the Feature."
+ return get_feat_field_count(self._ptr)
+
+ @property
+ def fields(self):
+ "Returns a list of fields in the Feature."
+ return [get_field_name(get_field_defn(self._fdefn, i))
+ for i in xrange(self.num_fields)]
+
+ @property
+ def geom(self):
+ "Returns the OGR Geometry for this Feature."
+ # Retrieving the geometry pointer for the feature.
+ geom_ptr = get_feat_geom_ref(self._ptr)
+ return OGRGeometry(clone_geom(geom_ptr))
+
+ @property
+ def geom_type(self):
+ "Returns the OGR Geometry Type for this Feture."
+ return OGRGeomType(get_fd_geom_type(self._fdefn))
+
+ #### Feature Methods ####
+ def get(self, field):
+ """
+ Returns the value of the field, instead of an instance of the Field
+ object. May take a string of the field name or a Field object as
+ parameters.
+ """
+ field_name = getattr(field, 'name', field)
+ return self[field_name].value
+
+ def index(self, field_name):
+ "Returns the index of the given field name."
+ i = get_field_index(self._ptr, field_name)
+ if i < 0: raise OGRIndexError('invalid OFT field name given: "%s"' % field_name)
+ return i