diff -r 5176ba000a67 -r 25b7c445cf61 demos/dragon.py
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/demos/dragon.py	Mon Nov 26 17:31:37 2007 +0100
@@ -0,0 +1,55 @@
+#!/usr/bin/python
+
+# this demo needs dragon model from
+# http://graphics.stanford.edu/data/3Dscanrep/
+
+import sys
+sys.path.append("..")
+
+from raytracer import Raytracer, Light, Sphere, Triangle, Material
+import Image
+
+def LoadStanfordPlyFile(rt, mat, filename, scale):
+	vertices = []
+	fp = file(filename)
+	# read header
+	tokens = (0,)
+	while (tokens[0] != "end_header"):
+		tokens = fp.readline().split()
+		if (tokens[0] == "element"):
+			if (tokens[1] == "vertex"):
+				vertex_num = int(tokens[2])
+			if (tokens[1] == "face"):
+				face_num = int(tokens[2])
+
+	# read vertices
+	while (vertex_num):
+		tokens = fp.readline().split()
+		v = [scale*float(x) for x in tokens[0:3]]
+		#v[0] = -v[0]
+		v[1] = v[1]-3.5
+		#v[2] = -v[2]
+		vertices.append(tuple(v))
+		vertex_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[1], f[2], mat)
+		rt.addshape(face)
+		face_num -= 1
+
+rt = Raytracer()
+mat = Material(colour=(0.9, 0.9, 0.9))
+LoadStanfordPlyFile(rt, mat, "dragon_vrip.ply", 30.0)
+
+light = Light(position=(-5.0, 2.0, -8.0), colour=(0.9, 0.3, 0.6))
+rt.addlight(light)
+
+imagesize = (800, 600)
+data = rt.render(imagesize)
+img = Image.fromstring("RGB", imagesize, data)
+img.save('dragon.png')