Exemple #1
    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.
        if isinstance(geo_input, basestring):
            if isinstance(geo_input, unicode):
                # Encoding to ASCII, WKT or HEXEWKB doesn't need any more.
                geo_input = geo_input.encode('ascii')

            wkt_m = wkt_regex.match(geo_input)
            if wkt_m:
                # Handling WKT input.
                if wkt_m.group('srid'): srid = int(wkt_m.group('srid'))
                g = wkt_r().read(wkt_m.group('wkt'))
            elif hex_regex.match(geo_input):
                # Handling HEXEWKB input.
                g = wkb_r().read(geo_input)
            elif gdal.GEOJSON and json_regex.match(geo_input):
                # Handling GeoJSON input.
                g = wkb_r().read(gdal.OGRGeometry(geo_input).wkb)
                raise ValueError('String or unicode input unrecognized as WKT EWKT, and HEXEWKB.')
        elif isinstance(geo_input, GEOM_PTR):
            # When the input is a pointer to a geomtry (GEOM_PTR).
            g = geo_input
        elif isinstance(geo_input, buffer):
            # 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)
            # Invalid geometry type.
            raise TypeError('Improper geometry input type: %s' % str(type(geo_input)))

        if bool(g):
            # Setting the pointer object with a valid pointer.
            self.ptr = g
            raise GEOSException('Could not initialize GEOS Geometry with given input.')

        # Post-initialization setup.
Exemple #2
    def __init__(self, geom_input, srs=None):
        "Initializes Geometry on either WKT or an OGR pointer as input."

        str_instance = isinstance(geom_input, basestring)

        # If HEX, unpack input to to a binary buffer.
        if str_instance and hex_regex.match(geom_input):
            geom_input = buffer(a2b_hex(geom_input.upper()))
            str_instance = False

        # Constructing the geometry,
        if str_instance:
            # Checking if unicode
            if isinstance(geom_input, unicode):
                # Encoding to ASCII, WKT or HEX doesn't need any more.
                geom_input = geom_input.encode('ascii')

            wkt_m = wkt_regex.match(geom_input)
            json_m = json_regex.match(geom_input)
            if wkt_m:
                if wkt_m.group('srid'):
                    # If there's EWKT, set the SRS w/value of the SRID.
                    srs = int(wkt_m.group('srid'))
                if wkt_m.group('type').upper() == 'LINEARRING':
                    # OGR_G_CreateFromWkt doesn't work with LINEARRING WKT.
                    #  See http://trac.osgeo.org/gdal/ticket/1992.
                    g = capi.create_geom(OGRGeomType(wkt_m.group('type')).num)
                    capi.import_wkt(g, byref(c_char_p(wkt_m.group('wkt'))))
                    g = capi.from_wkt(
                        byref(c_char_p(wkt_m.group('wkt'))), None,
            elif json_m:
                if GEOJSON:
                    g = capi.from_json(geom_input)
                    raise NotImplementedError(
                        'GeoJSON input only supported on GDAL 1.5+.')
                # Seeing if the input is a valid short-hand string
                # (e.g., 'Point', 'POLYGON').
                ogr_t = OGRGeomType(geom_input)
                g = capi.create_geom(OGRGeomType(geom_input).num)
        elif isinstance(geom_input, buffer):
            # WKB was passed in
            g = capi.from_wkb(
                str(geom_input), None, byref(c_void_p()), len(geom_input))
        elif isinstance(geom_input, OGRGeomType):
            # OGRGeomType was passed in, an empty geometry will be created.
            g = capi.create_geom(geom_input.num)
        elif isinstance(geom_input, self.ptr_type):
            # OGR pointer (c_void_p) was the input.
            g = geom_input
            raise OGRException(
                'Invalid input type for OGR Geometry construction: %s' %

        # Now checking the Geometry pointer before finishing initialization
        # by setting the pointer for the object.
        if not g:
            raise OGRException(
                'Cannot create OGR Geometry from input: %s' % str(geom_input))
        self.ptr = g

        # Assigning the SpatialReference object to the geometry, if valid.
        if bool(srs): self.srs = srs

        # Setting the class depending upon the OGR Geometry Type
        self.__class__ = GEO_CLASSES[self.geom_type.num]