F1 2012 Multiplayer Question

mungopark · May 12, 2013

maybe a silly question

:

sometimes, in online races, there is a strange behaviour.
cars in front of me go off the track because of an accident/a mistake and i pass them. but all over sudden, they are in front of me again without passing me just as they were fallen from the sky and look like ghostcars for a short time.
that is really annoying

.

is this a bug? do people cheat somehow? or is there another reason? has anybody noticed that issue, too?

thanks.

Graham Laing · May 12, 2013

Sounds like really bad lag on a host with a poor connection (or your connection is poor).

What you are probably seeing when the other cars appear to have accidents or make mistakes, is your game estimating what the other cars are doing, based on the last known car trajectory data. Then when the connection improves, and your game gets a car position update for the other players, they are suddenly in front of you, where they really were all the time, your game just didn't know it.

I am assuming that racing games in multiplayer are much like FPS games. Using client sided prediction (your game being the client). A regular stream of updates from the server (host), would update your client with everyone's position, when some of that data is missing or delayed, your client is predicting what will happen to everyone if they carry on based on their last position/trajectory data, and that's what you see until the next update from the host happens.

This may not be totally true, but is probably a good guess on what roughly happens.

This is part of the main reason that the best way to to run games is with a dedicated server, and not P2P lobbies.

Of course dedicated servers are not everything, because some games have dedicated servers AND client sided prediction, Battlefield 3 for example. In this case the client sided prediction means that you often drop dead AFTER getting behind cover or moving around a corner. Your client predicted that you were safe, then the server update says no ..... you were shot before you got there.