Line plane intersection: what is this variable?

Question

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.

Thanks,

James

Answer 1

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