Making an unlit object smoothly fade to black using Amplify Shader Editor's light attenuation node

[karmic sedge]

I want to use ASE's light attenuation node and get the average amount of black and white in the model, then use that to color the entire model at once, making the model go from fully black to fully white based on how much it is being shaded

here's what I want the models to do, going from fully white to fully gray until they are completely black once covered by a shade

as stated I am using Amplify Shader Editor, and that's a hard requirement. I can probably follow instructions using equivalent Shader Graph nodes

the effect pictured in the OP comes from this node, and I was hoping to get an average of every vertex to get the expected level of gray based on the environment

[whole plaza]

You can't really do that in one draw. Individual pixels basically have no idea what's going on in other pixels.

Attenuation is usually the result of lighting calculation, so it's based on the fragment normal, light direct, shadows and such.

[boreal lance]

With custom light attenuation it could be kind of done with a flattened light ramp
But shadows are way trickier because they cannot be inferred from the distance to the light or other light data available at that stage

[karmic sedge]

I see. I'm way out of my depth here, so thanks for the help

what would be the best way to achieve a similar effect then?

[wary wharf]

My solution would probably be to create a secondary red channel texture that's identical to the model's UV map and populate these lighting values, then on a secondary pass you'd evaluate the texture then color accordingly.