Did some more work on a basic realtime toon shader for XSI (and maya, it’s CGFX.) Here’s a sample…
Functionality is pretty basic at the moment: Ink threshold, 2 levels of paint and a hard spec hilight, overall color control, a single point light source. I still need to introduce diffusion and spec mapping, possibly some reflections and bump/normal. Remember, if you see an agent, run.
I’ve been playing around with a little app on my iPhone which creates NPR sketch effects from photos (I gather made by Bruce Gooch, who has done a lot to advance the state of the art in ‘painterly’ and ‘sketchy’ image manipulation.) ToonFX
The app is simple but with a little effort and insight you can get some good results.