--- 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); };
 };