web/lib/django/contrib/gis/geos/point.py
changeset 0 0d40e90630ef
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/web/lib/django/contrib/gis/geos/point.py	Wed Jan 20 00:34:04 2010 +0100
@@ -0,0 +1,135 @@
+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