"Bald Eagle" <cre### [at] netscapenet> wrote:
> > "Mike Miller" <mil### [at] gmailcom> wrote:
>
> > > Not sure how to get the edge and cel-shade look directly from POV.
>
> So, I found a simple shader that does exactly what I suspected we needed to do -
> discretize the color values.
>
> https://www.shadertoy.com/view/XltGR7
>
> [GLSL code]
>
> Now, I'm not sure if there's a way to accomplish that through the under-the-hood
> raytracer, but the docs provide SDL code to write your own raytracer, and then I
> suppose the lighting could be "toon-mapped" to get the desired effect.

All the values we need are not provided in POV's SDL, I think :(

> W F Pokorny used to have some info on his wiki user page describing making a
> stepped function from a smooth function - which I've recently played with while
> exploring some noise functions.
>
> Now, since specular is basically AOI, we might be able to to just use the aoi
> pattern with an appropriate color map to achieve a decent result.
>
> - BW

I'm not sure specular is basically just AOI. And the AOI pattern is ok for
getting the edges for curved objects, but it produces varied results based on
objects' curvature, with sharp-edged objects failing completely. To get
everything, we would need to render things in at least two passes, with the
edge-finding pass evaluating a function...

Sam

Post a reply to this message