--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/app/django/contrib/gis/geos/prototypes/geom.py	Tue Oct 14 16:00:59 2008 +0000
@@ -0,0 +1,111 @@
+from ctypes import c_char_p, c_int, c_size_t, c_uint, POINTER
+from django.contrib.gis.geos.libgeos import lgeos, CS_PTR, GEOM_PTR
+from django.contrib.gis.geos.prototypes.errcheck import \
+    check_geom, check_minus_one, check_sized_string, check_string, check_zero
+
+### ctypes generation functions ###
+def bin_constructor(func):
+    "Generates a prototype for binary construction (HEX, WKB) GEOS routines."
+    func.argtypes = [c_char_p, c_size_t]
+    func.restype = GEOM_PTR
+    func.errcheck = check_geom
+    return func
+
+# HEX & WKB output
+def bin_output(func):
+    "Generates a prototype for the routines that return a a sized string."
+    func.argtypes = [GEOM_PTR, POINTER(c_size_t)]
+    func.errcheck = check_sized_string
+    return func
+
+def geom_output(func, argtypes):
+    "For GEOS routines that return a geometry."
+    if argtypes: func.argtypes = argtypes
+    func.restype = GEOM_PTR
+    func.errcheck = check_geom
+    return func
+
+def geom_index(func):
+    "For GEOS routines that return geometries from an index."
+    return geom_output(func, [GEOM_PTR, c_int])
+
+def int_from_geom(func, zero=False):
+    "Argument is a geometry, return type is an integer."
+    func.argtypes = [GEOM_PTR]
+    func.restype = c_int
+    if zero: 
+        func.errcheck = check_zero
+    else:
+        func.errcheck = check_minus_one
+    return func
+
+def string_from_geom(func):
+    "Argument is a Geometry, return type is a string."
+    # We do _not_ specify an argument type because we want just an
+    # address returned from the function.
+    func.argtypes = [GEOM_PTR]
+    func.errcheck = check_string
+    return func
+
+### ctypes prototypes ###
+
+# TODO: Tell all users to use GEOS 3.0.0, instead of the release 
+#  candidates, and use the new Reader and Writer APIs (e.g.,
+#  GEOSWKT[Reader|Writer], GEOSWKB[Reader|Writer]).  A good time
+#  to do this will be when Refractions releases a Windows PostGIS
+#  installer using GEOS 3.0.0.
+
+# Creation routines from WKB, HEX, WKT
+from_hex = bin_constructor(lgeos.GEOSGeomFromHEX_buf)
+from_wkb = bin_constructor(lgeos.GEOSGeomFromWKB_buf)
+from_wkt = geom_output(lgeos.GEOSGeomFromWKT, [c_char_p])
+
+# Output routines
+to_hex = bin_output(lgeos.GEOSGeomToHEX_buf)
+to_wkb = bin_output(lgeos.GEOSGeomToWKB_buf)
+to_wkt = string_from_geom(lgeos.GEOSGeomToWKT)
+
+# The GEOS geometry type, typeid, num_coordites and number of geometries
+geos_normalize = int_from_geom(lgeos.GEOSNormalize)
+geos_type = string_from_geom(lgeos.GEOSGeomType)
+geos_typeid = int_from_geom(lgeos.GEOSGeomTypeId)
+get_dims = int_from_geom(lgeos.GEOSGeom_getDimensions, zero=True)
+get_num_coords = int_from_geom(lgeos.GEOSGetNumCoordinates)
+get_num_geoms = int_from_geom(lgeos.GEOSGetNumGeometries)
+
+# Geometry creation factories
+create_point = geom_output(lgeos.GEOSGeom_createPoint, [CS_PTR])
+create_linestring = geom_output(lgeos.GEOSGeom_createLineString, [CS_PTR]) 
+create_linearring = geom_output(lgeos.GEOSGeom_createLinearRing, [CS_PTR])
+
+# Polygon and collection creation routines are special and will not
+# have their argument types defined.
+create_polygon = geom_output(lgeos.GEOSGeom_createPolygon, None)
+create_collection = geom_output(lgeos.GEOSGeom_createCollection, None)
+
+# Ring routines
+get_extring = geom_output(lgeos.GEOSGetExteriorRing, [GEOM_PTR])
+get_intring = geom_index(lgeos.GEOSGetInteriorRingN)
+get_nrings = int_from_geom(lgeos.GEOSGetNumInteriorRings)
+
+# Collection Routines
+get_geomn = geom_index(lgeos.GEOSGetGeometryN)
+
+# Cloning
+geom_clone = lgeos.GEOSGeom_clone
+geom_clone.argtypes = [GEOM_PTR]
+geom_clone.restype = GEOM_PTR
+
+# Destruction routine.
+destroy_geom = lgeos.GEOSGeom_destroy
+destroy_geom.argtypes = [GEOM_PTR]
+destroy_geom.restype = None
+
+# SRID routines
+geos_get_srid = lgeos.GEOSGetSRID
+geos_get_srid.argtypes = [GEOM_PTR]
+geos_get_srid.restype = c_int
+
+geos_set_srid = lgeos.GEOSSetSRID
+geos_set_srid.argtypes = [GEOM_PTR, c_int]
+geos_set_srid.restype = None