--- a/include/scene.h	Wed Mar 26 17:03:38 2008 +0100
+++ b/include/scene.h	Fri Mar 28 00:53:20 2008 +0100
@@ -63,13 +63,13 @@
 {
 public:
 	Vector3 eye, p, u, v;
-	Float f;
+	Float f,F;
 
-	Camera(): eye(0,0,10), p(0,0,-1), u(-1,0,0), v(0,1,0), f(3.14/4.0) {};
+	Camera(): eye(0,0,10), p(0,0,-1), u(-1,0,0), v(0,1,0), f(3.14/4.0), F(0.5/f) {};
 	Camera(const Vector3 &C, const Vector3 &ap, const Vector3 &au, const Vector3 &av):
-		eye(C), p(ap), u(au), v(av), f(3.14/4.0) {};
+		eye(C), p(ap), u(au), v(av), f(3.14/4.0), F(0.5/f) {};
 	void setEye(const Vector3 &aeye) { eye = aeye; };
-	void setFocalLength(const Float af) { f = af; };
+	void setFocalLength(const Float af) { f = af; F = 0.5/f; };
 	void rotate(const Quaternion &q);
 	void move(const Float fw, const Float left, const Float up);