--- a/ccdemos/realtime_bunny.cc	Fri Dec 14 00:05:54 2007 +0100
+++ b/ccdemos/realtime_bunny.cc	Fri Dec 14 10:34:31 2007 +0100
@@ -6,8 +6,8 @@
 #include <fstream>
 #include <iomanip>
 
-int w = 320;
-int h = 200;
+int w = 640;
+int h = 400;
 Float *render_buffer;
 
 Raytracer rt;

--- a/ccdemos/realtime_dragon.cc	Fri Dec 14 00:05:54 2007 +0100
+++ b/ccdemos/realtime_dragon.cc	Fri Dec 14 10:34:31 2007 +0100
@@ -1,7 +1,7 @@
 #include <SDL.h>
 
 #include "raytracer.h"
-#include "kdtree.h"
+#include "octree.h"
 #include <iostream>
 #include <fstream>
 
@@ -41,8 +41,7 @@
 
 	// read vertices
 	Vector3 P;
-	int num = vertex_num;
-	while (num--)
+	for (int i = 0; i < vertex_num; i++)
 	{
 		f >> P.x >> P.y >> P.z;
 		P.x = -scale*P.x;
@@ -56,7 +55,7 @@
 	// read faces
 	Triangle *face;
 	int v1, v2, v3;
-	while (face_num--)
+	for (int i = 0; i < face_num; i++)
 	{
 		f >> num;
 		if (num != 3)
@@ -77,7 +76,7 @@
 		vertex_face_num.at(v3)++;
 	}
 
-	for (int i; i < vertex_num; i++)
+	for (int i = 0; i < vertex_num; i++)
 	{
 		normals.at(i) /= vertex_face_num.at(i);
 		normals.at(i).normalize();
@@ -140,10 +139,10 @@
 	/* initialize raytracer and prepare scene */
 	render_buffer = (Float *) malloc(w*h*3*sizeof(Float));
 
-	rt.setThreads(1);
-	rt.setMaxDepth(3);
+	rt.setThreads(2);
+	rt.setMaxDepth(0);
 
-	KdTree top;
+	Octree top;
 	rt.setTop(&top);
 
 	Light light1(Vector3(-5.0, 2.0, 8.0), Colour(0.9, 0.3, 0.6));
@@ -155,13 +154,11 @@
 	//rt.addlight(&light2);
 
 	Material mat(Colour(0.9, 0.9, 0.9));
-	load_ply("../models/dragon/dragon_vrip_res4.ply", &mat, 29);
+	load_ply("../models/dragon/dragon_vrip.ply", &mat, 29);
 
 	rt.setCamera(&cam);
 	cam.setEye(Vector3(0,0,10));
 
-	/* build kd-tree */
-	top.setMaxDepth(30);
 	top.optimize();
 
 	/* loop... */

--- a/demos/buddha.py	Fri Dec 14 00:05:54 2007 +0100
+++ b/demos/buddha.py	Fri Dec 14 10:34:31 2007 +0100
@@ -12,7 +12,7 @@
 
 rt = Raytracer()
 mat = Material(colour=(0.9, 0.9, 0.9))
-LoadStanfordPlyFile(rt, "../models/happy/happy_vrip_res4.ply",
+LoadStanfordPlyFile(rt, "../models/happy/happy_vrip_res2.ply",
 	mat, smooth=True, scale=20.0, trans=(0,-3,0))
 
 light = Light(position=(-5.0, 2.0, 8.0), colour=(0.9, 0.3, 0.6))

--- a/demos/bunny.py	Fri Dec 14 00:05:54 2007 +0100
+++ b/demos/bunny.py	Fri Dec 14 10:34:31 2007 +0100
@@ -6,7 +6,7 @@
 import sys
 sys.path.append(open('ModulePath').read().strip())
 
-from raytracer import Raytracer, Light, Box, Triangle, NormalVertex, Material
+from raytracer import Raytracer, Light, Box, Triangle, Material
 from plyreader import LoadStanfordPlyFile
 import Image
 

--- a/include/scene.h	Fri Dec 14 00:05:54 2007 +0100
+++ b/include/scene.h	Fri Dec 14 10:34:31 2007 +0100
@@ -156,7 +156,7 @@
 		center(acenter), radius(aradius) { material = amaterial; }
 	bool intersect(const Ray &ray, Float &dist) const;
 	bool intersect_all(const Ray &ray, Float dist, vector<Float> &allts) const;
-	bool intersect_bbox(const BBox &bbox) const { return true; };
+	bool intersect_bbox(const BBox &bbox) const;
 	const Vector3 normal(const Vector3 &P) const { return (P - center) * inv_radius; };
 	BBox get_bbox() const;
 };
@@ -175,7 +175,7 @@
 	};
 	bool intersect(const Ray &ray, Float &dist) const;
 	bool intersect_all(const Ray &ray, Float dist, vector<Float> &allts) const { return false; };
-	bool intersect_bbox(const BBox &bbox) const { return true; };
+	bool intersect_bbox(const BBox &bbox) const;
 	const Vector3 normal(const Vector3 &P) const;
 	BBox get_bbox() const { return BBox(L, H); };
 };

--- a/src/octree.cc	Fri Dec 14 00:05:54 2007 +0100
+++ b/src/octree.cc	Fri Dec 14 10:34:31 2007 +0100
@@ -55,7 +55,8 @@
 			}
 	}
 
-	if (shapes->size() <= 8 && shapenum > 2*shapes->size())
+	if ((shapes->size() <= 8 && shapenum > 2*shapes->size())
+	|| shapenum >= 6*shapes->size())
 	{
 		// bad subdivision, revert
 		delete[] children;
@@ -78,7 +79,6 @@
 	ShapeList::iterator shape;
 	for (shape = shapes.begin(); shape != shapes.end(); shape++)
 		root->addShape(*shape);
-
 	root->subdivide(bbox, max_depth);
 	built = true;
 }
@@ -184,7 +184,7 @@
 	st_cur->next = -1;
 
 	Shape *nearest_shape = NULL;
-	while (nearest_shape == NULL)
+	for (;;)
 	{
 		if (st_cur->next == -1)
 		{
@@ -196,17 +196,16 @@
 				if (node->isLeaf())
 				{
 					ShapeList::iterator shape;
-					register Float mindist = max3(tx0,ty0,tz0);
-					/* correct & slow */
-					//Float dist = min(min3(tx1,ty1,tz1),nearest_distance);
-					/* faster */
-					register Float dist = nearest_distance;
+					//register Float mindist = max3(tx0,ty0,tz0);
+					register Float dist = min(nearest_distance, min3(tx1,ty1,tz1));
 					for (shape = node->shapes->begin(); shape != node->shapes->end(); shape++)
-						if (*shape != origin_shape && (*shape)->intersect(ray, dist) && dist >= mindist)
+						if (*shape != origin_shape && (*shape)->intersect(ray, dist))
 						{
 							nearest_shape = *shape;
 							nearest_distance = dist;
 						}
+					if (nearest_shape != NULL)
+						return nearest_shape;
 				}
 				else
 				{
@@ -327,5 +326,4 @@
 		}
 		st_cur->next = -1;
 	}
-	return nearest_shape;
 }

--- a/src/scene.cc	Fri Dec 14 00:05:54 2007 +0100
+++ b/src/scene.cc	Fri Dec 14 10:34:31 2007 +0100
@@ -144,19 +144,31 @@
 	return false;
 }
 
+bool Sphere::intersect_bbox(const BBox &bbox) const
+{
+	register float dmin = 0;
+	for (int i = 0; i < 3; i++)
+	{
+		if (center[i] < bbox.L[i])
+			dmin += (center[i] - bbox.L[i])*(center[i] - bbox.L[i]);
+		else
+		if (center[i] > bbox.H[i])
+			dmin += (center[i] - bbox.H[i])*(center[i] - bbox.H[i]);
+	}
+	if (dmin <= sqr_radius)
+		return true;
+	return false;
+};
+
 BBox Sphere::get_bbox() const
 {
-	BBox bbox = BBox();
-	bbox.L = center - radius;
-	bbox.H = center + radius;
-	return bbox;
+	return BBox(center - radius, center + radius);
 }
 
 bool Box::intersect(const Ray &ray, Float &dist) const
 {
 	Float a,b;
-	bool res = get_bbox().intersect(ray, a, b);
-	if (res && a < dist)
+	if (get_bbox().intersect(ray, a, b) && a < dist)
 	{
 		dist = a;
 		return true;
@@ -165,6 +177,14 @@
 		return false;
 }
 
+bool Box::intersect_bbox(const BBox &bbox) const
+{
+	return (
+	H.x > bbox.L.x && L.x < bbox.H.x &&
+	H.y > bbox.L.y && L.y < bbox.H.y &&
+	H.z > bbox.L.z && L.z < bbox.H.z);
+}
+
 const Vector3 Box::normal(const Vector3 &P) const
 {
 	Vector3 N;