Ready at dawn layered approach in unity

I was looking into new HDPipeline layered shader and noticed that it support blending only 4 layers by vertex color or texture mask. I dont know details behind Ready at dawn shader blending but they can easily create as much layers as they want. They are using library of basic tiling materials and blend them together for creating complex materials with baking only grayscale masks for layers. This approach allows you to save big amount of texture space and video memory. It also allows you to not worry about the sizes of your meshes and texel density. I think it will be very good alternative for current baked asset pipeline in unity.

 

Ready at dawn only used a 4 layer blend. However most of their tilable textures where generated by layering a library of base materials in an offline manner. Nowadays this workflow is done through a 4 layer shader + substance designer, which has all the features of their offline pipeline and more. SD even has scanning tools.

Using more than 4 layers would be pretty suicidal for performance. Especially for deferred renderers.
Even if you pack your maps really tight its still about 3 maps per material layer.

For each Material layer:
BaseColor(RGB) Alpha(A)
Normal(RG)
Roughness(R) Metallic(G) AmbientOcclusion(B) Specular(A)

For each Material
Mask(RGB) Mesh AO(A)

So if you have 4 material layers thats already 13 texture samples per pixel per material. This means you're pushing a lot of of data through your GPU. Deferred renderers are usually already bound by how much memory they can move. Its not the end of the world but its something you don't want to push too far.

TLDR: Unity already supports the workflow from ready at dawn and better than they had at the time.