Esempio n. 1
0
 def ogr(self):
     "Returns the OGR Geometry for this Geometry."
     if self.srid:
         try:
             return gdal.OGRGeometry(self.wkb, self.srid)
         except gdal.SRSException:
             pass
     return gdal.OGRGeometry(self.wkb)
Esempio n. 2
0
 def ogr(self):
     "Returns the OGR Geometry for this Geometry."
     if not gdal.HAS_GDAL:
         raise GEOSException('GDAL required to convert to an OGRGeometry.')
     if self.srid:
         try:
             return gdal.OGRGeometry(self.wkb, self.srid)
         except gdal.SRSException:
             pass
     return gdal.OGRGeometry(self.wkb)
Esempio n. 3
0
    def __init__(self, geo_input, srid=None):
        """
        The base constructor for GEOS geometry objects, and may take the
        following inputs:

         * strings:
            - WKT
            - HEXEWKB (a PostGIS-specific canonical form)
            - GeoJSON (requires GDAL)
         * buffer:
            - WKB

        The `srid` keyword is used to specify the Source Reference Identifier
        (SRID) number for this Geometry.  If not set, the SRID will be None.
        """
        input_srid = None
        if isinstance(geo_input, bytes):
            geo_input = force_text(geo_input)
        if isinstance(geo_input, str):
            wkt_m = wkt_regex.match(geo_input)
            if wkt_m:
                # Handling WKT input.
                if wkt_m.group('srid'):
                    input_srid = int(wkt_m.group('srid'))
                g = wkt_r().read(force_bytes(wkt_m.group('wkt')))
            elif hex_regex.match(geo_input):
                # Handling HEXEWKB input.
                g = wkb_r().read(force_bytes(geo_input))
            elif json_regex.match(geo_input):
                # Handling GeoJSON input.
                g = wkb_r().read(gdal.OGRGeometry(geo_input).wkb)
            else:
                raise ValueError(
                    'String input unrecognized as WKT EWKT, and HEXEWKB.')
        elif isinstance(geo_input, GEOM_PTR):
            # When the input is a pointer to a geometry (GEOM_PTR).
            g = geo_input
        elif isinstance(geo_input, memoryview):
            # When the input is a buffer (WKB).
            g = wkb_r().read(geo_input)
        elif isinstance(geo_input, GEOSGeometry):
            g = capi.geom_clone(geo_input.ptr)
        else:
            # Invalid geometry type.
            raise TypeError('Improper geometry input type: %s' %
                            type(geo_input))

        if not g:
            raise GEOSException(
                'Could not initialize GEOS Geometry with given input.')

        input_srid = input_srid or capi.geos_get_srid(g) or None
        if input_srid and srid and input_srid != srid:
            raise ValueError('Input geometry already has SRID: %d.' %
                             input_srid)

        # Setting the pointer object with a valid pointer.
        self.ptr = g
        # Post-initialization setup.
        self._post_init(input_srid or srid)
Esempio n. 4
0
def convert_from_gk25(north, east):
    ps = "POINT (%f %f)" % (east, north)
    g = gdal.OGRGeometry(ps, GK25_SRS)
    if coord_transform:
        g.transform(coord_transform)
    return g

    pnt = Point(east, north, srid=GK25_SRID)
    if PROJECTION_SRID == GK25_SRID:
        return pnt
    pnt.transform(coord_transform)
    return pnt
Esempio n. 5
0
    def transform(self, ct, clone=False):
        """
        Requires GDAL. Transforms the geometry according to the given
        transformation object, which may be an integer SRID, and WKT or
        PROJ.4 string. By default, the geometry is transformed in-place and
        nothing is returned. However if the `clone` keyword is set, then this
        geometry will not be modified and a transformed clone will be returned
        instead.
        """
        srid = self.srid

        if ct == srid:
            # short-circuit where source & dest SRIDs match
            if clone:
                return self.clone()
            else:
                return

        if not gdal.HAS_GDAL:
            raise GEOSException(
                "GDAL library is not available to transform() geometry.")

        if isinstance(ct, gdal.CoordTransform):
            # We don't care about SRID because CoordTransform presupposes
            # source SRS.
            srid = None
        elif srid is None or srid < 0:
            raise GEOSException(
                "Calling transform() with no SRID set is not supported")

        # Creating an OGR Geometry, which is then transformed.
        g = gdal.OGRGeometry(self.wkb, srid)
        g.transform(ct)
        # Getting a new GEOS pointer
        ptr = wkb_r().read(g.wkb)
        if clone:
            # User wants a cloned transformed geometry returned.
            return GEOSGeometry(ptr, srid=g.srid)
        if ptr:
            # Reassigning pointer, and performing post-initialization setup
            # again due to the reassignment.
            capi.destroy_geom(self.ptr)
            self.ptr = ptr
            self._post_init(g.srid)
        else:
            raise GEOSException('Transformed WKB was invalid.')
Esempio n. 6
0
 def to_python(self, value):
     if value in self.empty_values:
         return None
     # Work with a single GeoJSON geometry or a Feature. Avoid parsing
     # overhead unless we have a true "Feature".
     if '"Feature",' in value:
         d = json.loads(value)
         value = json.dumps(d.get('geometry'))
     elif isinstance(value, collections.Mapping):
         value = json.dumps(value.get('geometry') or value)
     # Handle a comma delimited extent.
     elif list(value).count(',') == 3:
         value = Envelope(value.split(',')).polygon.ExportToWkt()
     try:
         geom = gdal.OGRGeometry(value)
     except (gdal.OGRException, TypeError, ValueError):
         raise forms.ValidationError(self.error_messages['invalid_geom'])
     if not geom.srs:
         geom.srid = self.srid or self.widget.map_srid
     return geom
Esempio n. 7
0
 def to_python(self, value):
     if value in self.empty_values:
         return None
     sref = None
     # Work with a single GeoJSON geometry or a Feature.
     value = json.loads(value) if '"Feature",' in value else value
     if isinstance(value, collections.Mapping):
         feat = sc.as_feature(value)
         value = json.dumps(feat.get('geometry') or value)
         sref = feat.srs
     # Handle a comma delimited extent.
     elif list(value).count(',') == 3:
         value = Envelope(value.split(',')).polygon.ExportToWkt()
     try:
         geom = gdal.OGRGeometry(value, srs=getattr(sref, 'wkt', None))
     except (gdal.OGRException, TypeError, ValueError):
         raise forms.ValidationError(self.error_messages['invalid_geom'])
     if not geom.srs:
         geom.srid = self.srid or self.widget.map_srid
     return geom
Esempio n. 8
0
 def ogr(self):
     "Return the OGR Geometry for this Geometry."
     return gdal.OGRGeometry(self._ogr_ptr(), self.srs)