Sphere mapping for NPR outlining...

I’ve been trying to replace my clunky outlining code (for non photorealistic rendering) with a slick sphere mapped approach like the one described here (http://www.cs.unc.edu/~hoff/projects/summer98_disney_lighting_effects/docs/outlining/).

So far all I have to go on is the outlining sphere map, the proof someone else got this working right, and some dissapointing results. I have sphere mapping working normally, but it would seem I need something more to get the effect I’m looking for.