It would be nifty if there was some mechanism to allow specifying rotated sprites.

Perhaps just look for a rotated_sprite property on the original equipment definition, and use that if present?

I don't believe this is something I can do on my end. I think the sprite rotation is an engine limitation.

Equipment prototypes specify that they need a Sprite specifically. RotatedSprites are only usable by specific prototypes, mainly artillery.

Or do you mean as a mechanism to allow other mod authors to register a rotated sprite with my mod?

Or do you mean as a mechanism to allow other mod authors to register a rotated sprite with my mod?

This is what I mean.

Ok, I wasn't aware that prototypes could have extra properties without failing some validation from Factorio.

I have added something for this in the newest version, see here for more details: https://github.com/DedlySpyder/Rotatable_Equipment#mod-compatibility

Cool. =)