How to apply 2D style rendering in 3D games?

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:bust_in_silhouette: Asked By SanSeiU

Recently I’m making a 3D game. I’m a beginner of godot and I learned something about shaders. One thing confusing me is that the fragment shader seems to be seperated into a fragment processor and a light processor iteratively called. Can’t they communicate? I want to access the diffuse color contributed by all the lights, and cast the diffuse lightness to a color ramp in order to get a 2D style rendering. I wonder if there is anyway to achieve it?
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