In the context of ray/box intersection, what exactly is "a valid intersection interval"? I've been searching through different tutorials, but it seems they mostly seem to expect this as a priori knowledge.
A:
It's the line segment between the point where the ray enters the box and the point where it leaves.
Jackson Pope
2010-10-17 14:51:52
+1
A:
Just a guess. Consider a ray as a line of infinite extent. If the ray intersects the box, then the intersection will happen as an interval on that line. One end of the interval is where it enters the box, the other end where it exits the box. The interval in question may reduce to a single point in some degenerate cases, where the ray just crosses an edge or vertex of the box.
woodchips
2010-10-17 14:55:43