This is fairly slow because I didn't bother to optimize the intersect
routine. Instead of using plane equations and such, I simply determines 
inside and outside by computing the area difference(eg cross product).

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Rendered picture in jpeg

<br>
<img src="ray4.jpg">
<br>

<applet code="RayTrace.class" width=500 height=500>
<param name="datafile" value="sample4.ray">
</applet>