Access to mesh normals in post process material?

Development Rendering
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I’m trying to apply an ink texture on a character AFTER lighting values have been calculated, so I can apply the texture as a shadow replacement via a post process volume without hacking myself into a corner on default lighting workflows.

I applied an alternate shadow texture using the “WorldAlignedTexture” node per UnrealCG’s tutorial on youtube… but in that implementation, as a mesh moves, the texture dances across it because the post process material is using world space normals. His solution was to ignore movable meshes via the “Render CustomDepth Pass” option… but I feel like it should be technically achievable.

For any material wizards out there, is there a way to “pass through” the mesh normals, so the texture doesn’t affect the lighting pass but could be accessed in a post process material?

If not, are there alternate approaches I might want to investigate… like decals that might not affect the SceneTexture-BaseColor nodes? Are there material domains, blend modes, or shading models that could apply the ink texture before the post process pass? Is there some crazy voodoo with lighting functions I could experiment with?

Any insights, suggestions, or armchair musings would be greatly appreciated.

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I guess i’m looking for the mesh UVs (not normals) in the post process material… but since that is not accessible by design (for render optimization?), I’ll just try experimenting more with textures on the base materials.

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You’d really probably need the world aligned local position. UVs are not good for projecting textures like that, because the UV unwrap might not be suitable for tileable textures, and objects can and often do have more than one set of UVs.

To get the world aligned local position, each object would need to write it’s origin point into a buffer accessable by the post process material, so it could be used as an offset against the world position. This would require a custom render pass, or highjacking/recycling an existing one (such as emissive). Depending on the other aspects of the art style, those would likely require engine modification.