Each slot requires at least one overlay set but usually receives a list of them. Overlays carries all the necessary textures to generate the final material(s) and might have extra information on how they are mapped. The first overlay in the list provides the base textures, and all other overlays included are combined with the first one, in sequence, generating the final atlas.
UMA standard shader requires three textures provided by overlays, one texture for Albedo/Diffuse color, one texture for Normal map, and Metallic/Roughness.
Multiple overlays on the same slot can work together by being layered on top of each other to achieve advanced effects.
For example, having a custom eye color. The color multiplier shouldn't change all of the eye, only the iris, so we have the base texture of the entire eye, and then layed over top of that is the iris texture where only the iris is opaque and the rest transparent (so the base texture is visible). Then the iris texture gets the color modification.
- After creating a new overlay asset, rename the file to a useful name.
- Give it a unique name in "Overlay Name".
- In "Material", select an appropriate UMA Material. The standard one is "UMA_Diffuse_Normal_Metallic".
- Finally, adjust the "Texture List" size and add textures to it's elements to match the UMA Material being used. For example, the standard "UMA_Diffuse_Normal_Metallic" has a size of 3 and takes an albedo texture in element 0, normal texture (remember to set the texture type to "normal") in element 1 and a metallic texture in element 2.
Overlay Name - Name the UMA system will use to refer to this overlay. This should be unique!
Overlay Type - Needs description
Rect - Needs description
Alpha Mask - Needs description
Texture List - Size along with elements to hold the references to textures.
Tags - Needs description
Material - The UMA Material this overlay uses.
Occlusion Entries - Needs description