[comp.graphics] icosahedron help

sulaiman@ecs.umass.edu (05/07/91)

I am trying to build a ray tracer that includes in its object files
an icosahedron. I am just wondering how people have defined each of the
faces of an icosahedron. For this purpose I am assuming an icosahedron
centered at 0,0,0 that is built inside a unit cube. I already know
the vertices and edges but how do you algebraicly(sp?) define a given
face so I can determine whether a ray hits it or not.
Thanx in advance.
Ameer.

P.S. Sorry if this seems like a truly trivial question to someone
out there.