from ctypes import c_uint from django.contrib.gis.geos.error import GEOSException from django.contrib.gis.geos.geometry import GEOSGeometry from django.contrib.gis.geos import prototypes as capi class Point(GEOSGeometry): _minlength = 2 _maxlength = 3 def __init__(self, x, y=None, z=None, srid=None): """ The Point object may be initialized with either a tuple, or individual parameters. For Example: >>> p = Point((5, 23)) # 2D point, passed in as a tuple >>> p = Point(5, 23, 8) # 3D point, passed in with individual parameters """ if isinstance(x, (tuple, list)): # Here a tuple or list was passed in under the `x` parameter. ndim = len(x) coords = x elif isinstance(x, (int, float, long)) and isinstance(y, (int, float, long)): # Here X, Y, and (optionally) Z were passed in individually, as parameters. if isinstance(z, (int, float, long)): ndim = 3 coords = [x, y, z] else: ndim = 2 coords = [x, y] else: raise TypeError('Invalid parameters given for Point initialization.') point = self._create_point(ndim, coords) # Initializing using the address returned from the GEOS # createPoint factory. super(Point, self).__init__(point, srid=srid) def _create_point(self, ndim, coords): """ Create a coordinate sequence, set X, Y, [Z], and create point """ if ndim < 2 or ndim > 3: raise TypeError('Invalid point dimension: %s' % str(ndim)) cs = capi.create_cs(c_uint(1), c_uint(ndim)) i = iter(coords) capi.cs_setx(cs, 0, i.next()) capi.cs_sety(cs, 0, i.next()) if ndim == 3: capi.cs_setz(cs, 0, i.next()) return capi.create_point(cs) def _set_list(self, length, items): ptr = self._create_point(length, items) if ptr: capi.destroy_geom(self.ptr) self._ptr = ptr self._set_cs() else: # can this happen? raise GEOSException('Geometry resulting from slice deletion was invalid.') def _set_single(self, index, value): self._cs.setOrdinate(index, 0, value) def __iter__(self): "Allows iteration over coordinates of this Point." for i in xrange(len(self)): yield self[i] def __len__(self): "Returns the number of dimensions for this Point (either 0, 2 or 3)." if self.empty: return 0 if self.hasz: return 3 else: return 2 def _get_single_external(self, index): if index == 0: return self.x elif index == 1: return self.y elif index == 2: return self.z _get_single_internal = _get_single_external def get_x(self): "Returns the X component of the Point." return self._cs.getOrdinate(0, 0) def set_x(self, value): "Sets the X component of the Point." self._cs.setOrdinate(0, 0, value) def get_y(self): "Returns the Y component of the Point." return self._cs.getOrdinate(1, 0) def set_y(self, value): "Sets the Y component of the Point." self._cs.setOrdinate(1, 0, value) def get_z(self): "Returns the Z component of the Point." if self.hasz: return self._cs.getOrdinate(2, 0) else: return None def set_z(self, value): "Sets the Z component of the Point." if self.hasz: self._cs.setOrdinate(2, 0, value) else: raise GEOSException('Cannot set Z on 2D Point.') # X, Y, Z properties x = property(get_x, set_x) y = property(get_y, set_y) z = property(get_z, set_z) ### Tuple setting and retrieval routines. ### def get_coords(self): "Returns a tuple of the point." return self._cs.tuple def set_coords(self, tup): "Sets the coordinates of the point with the given tuple." self._cs[0] = tup # The tuple and coords properties tuple = property(get_coords, set_coords) coords = tuple