def _check_src(self, src):
""" Basic check of source elements (sequence of points or polygons).
- array cast of source elements
- create ogr_src datasource/layer holding src points/polygons
- transforming source grid points/polygons to ogr.geometries on ogr.layer
"""
ogr_src = ogr_create_datasource('Memory', 'out')
try:
# is it ESRI Shapefile?
ds_in, tmp_lyr = io.open_shape(src, driver=ogr.GetDriverByName('ESRI Shapefile'))
ogr_src_lyr = ogr_src.CopyLayer(tmp_lyr, self._name)
if self._srs is None:
self._srs = ogr_src_lyr.GetSpatialRef()
except IOError:
# no ESRI shape file
raise
# all failed? then it should be sequence or numpy array
except RuntimeError:
src = np.array(src)
# create memory datasource, layer and create features
if src.ndim == 2:
geom_type = ogr.wkbPoint
# no Polygons, just Points
else:
geom_type = ogr.wkbPolygon
fields = [('index', ogr.OFTInteger)]
ogr_create_layer(ogr_src, self._name, srs=self._srs, geom_type=geom_type, fields=fields)
ogr_add_feature(ogr_src, src, name=self._name)
return ogr_src
def load_vector(self, filename):
""" Load source/target grid points/polygons into in-memory Shapefile
Parameters
----------
filename : string
path to vector file
"""
# get input file handles
ds_in, tmp = io.open_shape(filename)
# claim memory driver
drv_in = ogr.GetDriverByName('Memory')
# create all DataSources
self.src = DataSource(name='src')
self.src.ds = drv_in.CreateDataSource('src')
self.trg = DataSource(name='trg')
self.trg.ds = drv_in.CreateDataSource('trg')
self.dst = DataSource(name='dst')
self.dst.ds = drv_in.CreateDataSource('dst')
# copy all layers
ogr_copy_layer_by_name(ds_in, "src", self.src.ds)
ogr_copy_layer_by_name(ds_in, "trg", self.trg.ds)
ogr_copy_layer_by_name(ds_in, "dst", self.dst.ds)
# get spatial reference object
self._srs = self.src.ds.GetLayer().GetSpatialRef()
self.src._srs = self.src.ds.GetLayer().GetSpatialRef()
self.trg._srs = self.trg.ds.GetLayer().GetSpatialRef()
self.dst._srs = self.trg.ds.GetLayer().GetSpatialRef()
# flush everything
del ds_in
def load_vector(self, filename):
""" Load source/target grid points/polygons into in-memory Shapefile
Parameters
----------
filename : string
path to vector file
"""
# get input file handles
ds_in, tmp = io.open_shape(filename)
# create all DataSources
self.src = DataSource(name='src')
self.src.ds = io.gdal_create_dataset('Memory', 'src',
gdal_type=gdal.OF_VECTOR)
self.trg = DataSource(name='trg')
self.trg.ds = io.gdal_create_dataset('Memory', 'trg',
gdal_type=gdal.OF_VECTOR)
self.dst = DataSource(name='dst')
self.dst.ds = io.gdal_create_dataset('Memory', 'dst',
gdal_type=gdal.OF_VECTOR)
# copy all layers
georef.ogr_copy_layer_by_name(ds_in, "src", self.src.ds)
georef.ogr_copy_layer_by_name(ds_in, "trg", self.trg.ds)
georef.ogr_copy_layer_by_name(ds_in, "dst", self.dst.ds)
# get spatial reference object
self._srs = self.src.ds.GetLayer().GetSpatialRef()
self.src._srs = self.src.ds.GetLayer().GetSpatialRef()
self.trg._srs = self.trg.ds.GetLayer().GetSpatialRef()
self.dst._srs = self.trg.ds.GetLayer().GetSpatialRef()
# flush everything
del ds_in