diff -r e9bb83c2b8b9 -r ffe83ca074f3 demos/bunny.py
--- a/demos/bunny.py	Fri Dec 07 16:39:42 2007 +0100
+++ b/demos/bunny.py	Sat Dec 08 12:37:45 2007 +0100
@@ -6,11 +6,13 @@
 import sys
 sys.path.append(open('ModulePath').read().strip())
 
-from raytracer import Raytracer, Light, Sphere, Triangle, Material
+from raytracer import Raytracer, Light, Sphere, Triangle, NormalVertex, Material
 import Image
 
 def LoadStanfordPlyFile(rt, mat, filename, scale):
 	vertices = []
+	normals = []
+	vertex_face_num = []
 	fp = file(filename)
 	# read header
 	tokens = (0,)
@@ -23,27 +25,45 @@
 				face_num = int(tokens[2])
 
 	# read vertices
-	while (vertex_num):
+	num = vertex_num
+	while (num):
 		tokens = fp.readline().split()
 		v = [scale*float(x) for x in tokens[0:3]]
 		v[0] = -v[0]-1
 		v[1] = v[1]-3
-		vertices.append(tuple(v))
-		vertex_num -= 1
+		vertices.append(NormalVertex(tuple(v)))
+		normals.append([0.,0.,0.])
+		vertex_face_num.append(0)
+		num -= 1
 
 	# read faces
 	while (face_num):
 		tokens = fp.readline().split()
 		if (tokens[0] != "3"):
 			print "ply warning: faces of %d vertices not supported" % tokens[0]
-		f = [vertices[int(x)] for x in tokens[1:4]]
-		face = Triangle(f[0], f[2], f[1], mat)
+		v = [vertices[int(x)] for x in tokens[1:4]]
+		face = Triangle(v[0], v[2], v[1], mat)
+		n = face.getNormal()
+		for x in tokens[1:4]:
+			for i in range(3):
+				normals[int(x)][i] += n[i]
+			vertex_face_num[int(x)] += 1
+		face.setSmooth()
 		rt.addshape(face)
 		face_num -= 1
 
+	# interpolate normals at vertices
+	num = 0
+	while (num < vertex_num):
+		if (vertex_face_num[num] > 0):
+			for i in range(3):
+				normals[num][i] /= vertex_face_num[num]
+		vertices[num].setNormal(tuple(normals[num]))
+		num += 1
+
 rt = Raytracer()
 mat = Material(colour=(0.9, 0.9, 0.9))
-LoadStanfordPlyFile(rt, mat, "../models/bunny/bun_zipper_res3.ply", 29.0)
+LoadStanfordPlyFile(rt, mat, "../models/bunny/bun_zipper.ply", 29.0)
 
 light = Light(position=(-5.0, 2.0, 10.0), colour=(0.9, 0.3, 0.6))
 rt.addlight(light)