03/26/2002
15-462 Graphics I
20
Ray-Polygon Intersection III
•Rewrite using dot product
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•If n ¢ d = 0, no intersection
•If t · 0 the intersection is behind ray origin
•Point-in-triangle testing critical for polygonal models •Project onto planes x = 0, y = 0, or z = 0 for point-in-polygon test; can be precomputed