- Edited
Putting the two shaders together.
In most of his trees, Nagai consistently uses 4 easily distinguishable stippling layers:
- dark (almost black) silhouette layer, for parts that are completely in shadow.
- dark green layer for partially occluded/shadowed parts
- lighter green layer for lit parts
- some warm color layer for flowers/fruit.
So I tried to replicate that by layering the stippling shader. Density of dots is driven by Lambertian illumination. Eeach layer can remap the Lambert term differently to get different dot density falloff. I tweaked this manually aiming to match the appearance of original illustrations.
Size and offset of dots can also be adjusted per layer to make the whole thing less uniform.