100  // 300x300 pixel image
0.1 0.85  // ambient and diffuse reflection terms
-1.0 1.0 1.0  // Light source direction
50   // Sample the volume 50 times per ray looking for a change of sign.
3    // Take three iterations of the Bisection method.
0    // Take two Newton iterations.
1
1.0  //  iso-contour threshold value.
0 0 0 2.5 1.5    // Simple Sphere