diff -r 6641e941ef1e -r ff1a9aa48cfd app/django/contrib/gis/geos/collections.py --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/app/django/contrib/gis/geos/collections.py Tue Oct 14 16:00:59 2008 +0000 @@ -0,0 +1,105 @@ +""" + This module houses the Geometry Collection objects: + GeometryCollection, MultiPoint, MultiLineString, and MultiPolygon +""" +from ctypes import c_int, c_uint, byref +from types import TupleType, ListType +from django.contrib.gis.geos.base import GEOSGeometry +from django.contrib.gis.geos.error import GEOSException, GEOSIndexError +from django.contrib.gis.geos.geometries import Point, LineString, LinearRing, Polygon +from django.contrib.gis.geos.libgeos import get_pointer_arr, GEOM_PTR +from django.contrib.gis.geos.prototypes import create_collection, destroy_geom, geom_clone, geos_typeid, get_cs, get_geomn + +class GeometryCollection(GEOSGeometry): + _allowed = (Point, LineString, LinearRing, Polygon) + _typeid = 7 + + def __init__(self, *args, **kwargs): + "Initializes a Geometry Collection from a sequence of Geometry objects." + + # Checking the arguments + if not args: + raise TypeError, 'Must provide at least one Geometry to initialize %s.' % self.__class__.__name__ + + if len(args) == 1: + # If only one geometry provided or a list of geometries is provided + # in the first argument. + if isinstance(args[0], (TupleType, ListType)): + init_geoms = args[0] + else: + init_geoms = args + else: + init_geoms = args + + # Ensuring that only the permitted geometries are allowed in this collection + if False in [isinstance(geom, self._allowed) for geom in init_geoms]: + raise TypeError('Invalid Geometry type encountered in the arguments.') + + # Creating the geometry pointer array. + ngeoms = len(init_geoms) + geoms = get_pointer_arr(ngeoms) + for i in xrange(ngeoms): geoms[i] = geom_clone(init_geoms[i].ptr) + super(GeometryCollection, self).__init__(create_collection(c_int(self._typeid), byref(geoms), c_uint(ngeoms)), **kwargs) + + def __getitem__(self, index): + "Returns the Geometry from this Collection at the given index (0-based)." + # Checking the index and returning the corresponding GEOS geometry. + self._checkindex(index) + return GEOSGeometry(geom_clone(get_geomn(self.ptr, index)), srid=self.srid) + + def __setitem__(self, index, geom): + "Sets the Geometry at the specified index." + self._checkindex(index) + if not isinstance(geom, self._allowed): + raise TypeError('Incompatible Geometry for collection.') + + ngeoms = len(self) + geoms = get_pointer_arr(ngeoms) + for i in xrange(ngeoms): + if i == index: + geoms[i] = geom_clone(geom.ptr) + else: + geoms[i] = geom_clone(get_geomn(self.ptr, i)) + + # Creating a new collection, and destroying the contents of the previous poiner. + prev_ptr = self.ptr + srid = self.srid + self._ptr = create_collection(c_int(self._typeid), byref(geoms), c_uint(ngeoms)) + if srid: self.srid = srid + destroy_geom(prev_ptr) + + def __iter__(self): + "Iterates over each Geometry in the Collection." + for i in xrange(len(self)): + yield self.__getitem__(i) + + def __len__(self): + "Returns the number of geometries in this Collection." + return self.num_geom + + def _checkindex(self, index): + "Checks the given geometry index." + if index < 0 or index >= self.num_geom: + raise GEOSIndexError('invalid GEOS Geometry index: %s' % str(index)) + + @property + def kml(self): + "Returns the KML for this Geometry Collection." + return '%s' % ''.join([g.kml for g in self]) + + @property + def tuple(self): + "Returns a tuple of all the coordinates in this Geometry Collection" + return tuple([g.tuple for g in self]) + coords = tuple + +# MultiPoint, MultiLineString, and MultiPolygon class definitions. +class MultiPoint(GeometryCollection): + _allowed = Point + _typeid = 4 +class MultiLineString(GeometryCollection): + _allowed = (LineString, LinearRing) + _typeid = 5 +class MultiPolygon(GeometryCollection): + _allowed = Polygon + _typeid = 6