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I'm doing line plane intersection, and have come across an un-referenced variable or constant in the tutorial I'm following.

One of the formulae given is this:

t = N dot (p2 – p0)
     N dot V

The variable I'm stuck with is V. Can someone tell me what V is and how I'd go about finding it?

For more info on that formula, please see the link given in the first para.



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up vote 5 down vote accepted

Looks like V = p1 - p0. Since then t = 0 when p2 = p0, and t = 1 when p2 = p1.

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Thanks so much :-) just the answer I needed. I'd vote you up but I have 1 rep :-P – Bojangles Nov 14 '10 at 17:01
No worries! :) Glad it helped... – Stuart Golodetz Nov 14 '10 at 20:06

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