Toon shading model

[Arnage]

@DanielW;295941

Arnage, is super cool. We would love to support renderer extensions like , but unfortunately won’t be able to any time soon via code plugins and the like due to the amount of work involved.

It seems to me a nice implementation of custom shading is that there’s a Custom Shading Model you can pick per Material, and each project gets to supply a material which does the custom shading given Normal, LightVector, etc. is really difficult to implement though as there are lights that aren’t punctual, like sky lights and lightmaps, where there isn’t a LightVector at all. You have to write some spherical harmonic code for that and know a lot of math, so it won’t be the user friendly thing that’s desired.

The next best thing is to have a ‘Remapped Shading Model’ which simply allows the specification of a Lookup Texture for diffuse (addressed by dot(N, L)) and specular. It seems to me would be enough to implement all of your examples, is that the case? one is quite feasible to implement and similar to the Subsurface Profile shading model.

Thanks!

A full custom shading model might indeed get quite complex. Maybe you could provide a number of preset methods to handle those special case lights while providing full control over the easier to understand regular light handling? I think that should be enough for most use-cases, while not being too complicated for the user.

Regarding a “Remapped Shading Model”: that would indeed work for case. The only thing I’m not sure about would be mobile, which would be a shame as NPR visuals tend to be quite common in mobile games. You would lose one of the already scarce texture samplers and I’m not sure you wouldn’t get texture filtering artifacts due to lower precision combined with the high contrast lookup textures that would be needed for toon shading.