[quote=@Stekkmen]
gotta like how zhou yu doesn't know about glass

[/quote]

As someone who's Chinese, culturally I know glass wasn't very prevalent in architecture, windows being either just elaborate holes in the wall or covered by paper.  Just did some research and it turns out glass did exist in ancient China, but not as a building material, more as an art material. Its use halted towards late Han period and didn't resume until 3 centuries later. Since the three kingdoms period is in the late Han, I suppose it still makes sense for Zhou Yu to be unfamiliar with it, even less so as a building material.