It is currently impossible to layer multiple SurfaceAppearance maps on a single mesh.
I’m working on a game that will allow the player to customize their experience-wide avatar with patterns colors, etc. This becomes a problem because avatars will be a single deformed mesh and said customizations are impossible to create due to this limitation (if there is another way to do this I’m all ears). Right now my only option is to create a whole duplicate of the deformed mesh and set the SurfaceAppearance mode to transparency (again, CMIIW).
If Roblox were to address this request (and add something like a layer order/ZIndex property), it would significantly improve texture customization on a MeshPart, and remove the need for hacky workarounds.
Somewhat related to my recent request for Decals/Textures to be able to use UV maps; honestly I’ll happily take any form of support for layering mesh textures. Decals/Textures would be most ideal because they already have ZIndex, Color3 and Transparency properties, whereas SurfaceAppearances are lagging behind in realtime customizability.
I’m also interested in making a game with mesh deformation and customization, but this just doesn’t seem to be possible at this point in time. Such a basic feature shouldn’t require workarounds by developers.
It’s unfortunate that Roblox doesn’t allow more support for custom characters for those who want to make an experience independent of Roblox characters.
I’d love to make an experience that’s competitive off-platform and appeals to an older audience, but this is impossible the way things are right now.