diff -r fbd1d2f7d94e -r fc18ac4833f2 demos/spheres_ao.py
--- a/demos/spheres_ao.py	Sat Nov 24 23:55:54 2007 +0100
+++ b/demos/spheres_ao.py	Sun Nov 25 15:50:01 2007 +0100
@@ -3,7 +3,7 @@
 import sys
 sys.path.append("..")
 
-from raytracer import Raytracer, Material, Plane, Sphere, Light
+from raytracer import Raytracer, Material, Box, Sphere, Light
 import Image
 
 rt = Raytracer()
@@ -19,8 +19,8 @@
 
 mat0 = Material(colour=(0.7, 0.7, 0.7))
 
-plane = Plane(normal=(0.0, 1.0, 0.0), d=1.0, material=mat0)
-rt.addshape(plane)
+box = Box(L=(-20.0, -1.2, -20.0), H=(20.0, -1.0, 20.0), material=mat0)
+rt.addshape(box)
 
 mat1 = Material(colour=(1.0, 0.0, 0.0))
 bigsphere = Sphere(centre=(3.0, 2.0, 7.0), radius=3.0, material=mat1)