Like the title says i'm curious about what's the most efficient place to store these one channel maps? Right now i'm rewriting my texture pipeline and I don't know if I should pack the roughness in the alpha channel of the diffuse and compress it with BC3 or just put the roughness into its own texture compressed with BC4 then do the diffuse with BC1. I don't have a super deep understanding of exactly how GPUs work yet so i'm not sure which one would end up being better, so If someone with some more insight could weigh in I would appreciate it.
Thanks,
David