Depends on why someone is in the room, right? Having friends over, ignoring them and playing a game sounds rude, unless they are into it. But even then, it wou

Depends on why someone is in the room, right? Having friends over, ignoring them and playing a game sounds rude, unless they are into it. But even then, it would be more polite to let the guests play and the host watch. Sharing a flat with a roommate and playing a game while they do their own thing in the same room is certainly not rude.