Don't send mob movement/existence packets outside line of site
in Bugs
Change Request: Avoid sending monster/player updates when no line of site.
The EC and CC get sent monster status information, even when there is no line of site between the player and the monster. One side effect of that is you get to see monsters moving around in rooms that you have no line of site to. Likewise, you see player updates too, without line of site.
Maybe that was an optimization in the early days of UO? e.g. to limit the server side line of site calculations.
However, it seems more realistic to not get these updates when there is no line of site. It could be "cheaper" today to have the server check line of site, before sending these updates over the network.
Network egress may cost more than CPU now too.