That does look wrong, we need a new TextureFormatFeatureFlags::STORAGE_READ flag and TextureFormatFeatureFlags::STORAGE_READ_WRITE should be renamed to TextureFormatFeatureFlags::STORAGE_WRITE.

Question: Looking at the spec. section on Plain color formats in Texture format capabilities, it seems that STORAGE_READ and STORAGE_WRITE should be called STORAGE_READ_ONLY and STORAGE_WRITE_ONLY, respectively, with a separate STORAGE_READ_WRITE flag being necessary for determining if a flag can actually be used in a read/write scenario. Should this not be the final shape of feature bits?

it seems that STORAGE_READ and STORAGE_WRITE should be called STORAGE_READ_ONLY and STORAGE_WRITE_ONLY, respectively, with a separate STORAGE_READ_WRITE flag being necessary for determining if a flag can actually be used in a read/write scenario. Should this not be the final shape of feature bits?

That sounds correct to me.

Ah yes, you are right, I forgot we can't treat the presence of both read & write as read_write.

Apparently I forgot to click "comment" 😅

Yeah im aware, thats what i raised here: #6601

i thought that we could choose the semantics though, as long as their consistent. im not aware how much of this is spec defined. using 3 bits for this when 2 is enough to represent all states just feels a bit weird.

what happens when you set both READ_ONLY and READ_WRITE? or other invalid combinations?

i feel like read_write should be represented by READ | WRITE, write_only should be represented by only WRITE being set, same with read_only.

The problem is that a format can support read-only & write-only but not read-write (see table). We probably need another enum to encode this and it will depend on the context if we need to use the new enum or the bitflags.

The problem is that a format can support read-only & write-only but not read-write (see table). We probably need another enum to encode this and it will depend on the context if we need to use the new enum or the bitflags.

isnt that the same as not setting read or write?

read + write = read_write
read = read_only
write = write_only
none = read_only + write_only

No flag should mean that it doesn't support/use storage usage at all.

ahh okay. i am convinced that we should mirror the spec as closely as possible then, i'll get some PRs up this weekend