CGA would require very special kind of shaders. So let's talk about Unity shaders in this thread
I'm thinking about building something in 3D. I'd love to have 4 colors represent the shades of lighting on the object. I'm assuming Unity's ToonLit material with the right gradient texture (with CGA colors) should do the trick. I'm sleepy as hell, so I'll post experiment results tomorrow. Happy coding everyone!.. or drawing... or whatever the voodoo you do... happy whatevering!
I'm only just digging in but I'm finding great results with unlit shaders for materials and UV textures. I'm fairly new to Unity and I'm actually achieving the toon outline in Blender by setting up a duplicate object, scaled up, and normals calculated inside so the outside faces are culled in Unity. If someone has a better trick for the outline I'd be excited to hear about it.