Well... if you really wanna know: I want it for a 2-d line of sight system. I need to cast rays from each of the lights and when it finds an obstacle it stops...

Does anyone know how to make a line?

I've seen Fox's example, it's cool but it only works under some conditions.
I looked at the midpoint algorythm, it has the same problem.
I tried to make on myself, and it STILL had the same problem!

Please help! I'm really desperate!