title says it all. if caustic drops his gas canister in a room and it activates the cloud should not bleed through the walls out side of that room or into a hall way adjacent to a room.
I agree, but it depends on the cost. It's probably bleeding through walls now because they are doing a cheap spherical calculation from the center. If you change the shape of the gas to a more complex one that means more complex hit calculations for the server and additional culling calculations on the client.
As this is a minor issue I'd rather save performance unless they are able to optimize it so much it does not really matter.