Sorry to hear that you have been waiting for so long.
What Mitch used in the above video is a custom Diffuse Ramp
texture at a Sprite shader material. It's not available at the normal Skeleton Lit
shader, you have to use one of the Spine/Sprite
shaders (or their Lightweight Render Pipeline variants).
What happens here is that diffuse light is not evaluated in normal continuous fashion from 0-1
, but instead it looks at the ramp texture and uses the light intensity value that it finds there. Now if you paint three vertical bars in colors black, gray and white, it will result in such a cel-shaded lighting look with hard transitions between no light
, half lit
and fully lit
.
Maybe this posting here helps:
Sprite Shaders for Unity