I have a master material driving most objects in a scene to achieve a specific look. It has a normal map, a diffuse, maybe even an ambient occlusion map to make everything look like, for example, yarn. Here is a screenshot from a Nintendo game that seems to be doing just that.
This master material has various instances that get fed additional textures for detail normals, albedos tthat are mixed a bit with the master ones etc. How is texture fetching handled for the master normals for example? Does the engine fetch the normal map per object / material instance, removing the benefit, or does it fetch it once per frame and apply it everywhere it’s used? What kind of pros and cons am I facing? I’m especially interested in mobile performance.