I was reading the docs about detail maps, and according to this snippet
The detail map can contains albedo (diffuse), normal and roughness (for PBR materials only) channels, dispatched this way (following Unity convention):
Red channel: greyscale albedo
Green channel: green component of the normal map
Blue channel: roughness
Alpha channel: red component of the normal map
Unity uses Roughness Texture for the secondary map. I dont see any roughness texture slot anywhere on the Unity Shader… Only Secondary Albedo and Normal… So how could unity be packing roughness into the blue channel of the detail map ???
See here, Detail map section:
What about WITHOUT the HDRP… Just a regular 3D scene using standard shader. I still want to export the secondary albedo and normal map (this is no secondary smoothness/roughness maps in the standard shader)… Can i still just pack the red from the secondary albedo and the and the red and green from the normal and just a value of 0 or 1 for the roughness channel since i dont have a separate texture slot for that one ???
The standard material in Babylon is also using a detail map with this format but it is not using the roughness channel, so you can leave it with any value you want.