Using Vertex Paint for Dirt/Dust/Wear

Hello everyone,

I’m trying to set up a material that I can use together with Vertex Painting to put dust and whatnot on my objects and have a few questions regarding the process.

First of all, I want the material to check several Alpha Maps so that the end result looks believable. I was able to achieve this by using a chain of Lerp’s -for the Alpha Maps and the Vertex Color. But this makes things extremely difficult and complex down the line, as I have to c+p the entire chain for each material slot (metallic, roughness etc.) and it would be difficult to edit things later on.

So, I then tried using Make/BreakMaterialAttributes and MatLayerBlend. This worked brilliantly with an Alpha Map… except for the Normal Maps. The Normal Map of the base material works fine, but the dirty bits ignore the dirt Normal Map. (I’m only using Diffuse and Normal channels until I learn how this works, other channels may react similarly) I also have no idea where to introduce Vertex Color in this setup, so that’s another issue.

In short, I want a material that checks for both an Alpha Map and the Vertex Color (after I vertex paint the mesh) and puts dirt on where those two overlap.

Any ideas? I’d also really appreciate it if someone could share a similar material that I can play around with.

Thanks in advance.