Customizing Material Decal Response (UE5)

By default, UE5 applies a decals buffers (color, normal, roughness) on top of the underlying material with no respect to the characteristics of the underlying material itself. Here I show some examples of customizing the material response within the material which is receiving the decal itself, allowing for different kinds of materials to react uniquely. This can also be used to pass decal normals into the surface shader, which allowing for tangent space normal mapping to be correctly calculated, which could be useful for effects like tri-planar mapping of decals, or applying normal map decals to non-flat surfaces. I briefly explain how this is done using the dbuffer node, and encourage you to experiment with the decal response setting and sampling the buffer in your materials.