The online racing simulator
Does LFS normally have network lag issues when racing online?
Hi,

I have purchased S2 and it's a great sim - but the way cars jump all over the place when racing online is pretty ordinary.

The servers I connect to have sub 100ms pings, I dont have this issue with rFactor even on 100ms + servers !!

Is this just something you just have to accept with LFS - or are other ppl not having the same prob?

Thanks
That's completely normal for LFS. How strong this is visible depends on the server connectivity and setup, ranging from annoyingly jumpy to almost not noticeable.

It could be solved better, but every solution that removes jumpiness has other issues and drawbacks. The reason it's smooth in rFactor is because the other cars aren't bound to the actual physics. They just float on an interpolated line that roughly corresponds to what the opponent was actually doing. In LFS however the cars all continue to run on the physics engine, travelling along the path that they would've taken from the last received driver input. The jump occurs when the driver has changed his input between packets and drove to a different location than the physics calculated; this error is then corrected by warping the car to its actual position.
Quote from AndroidXP :That's completely normal for LFS. How strong this is visible depends on the server connectivity and setup, ranging from annoyingly jumpy to almost not noticeable.

It could be solved better, but every solution that removes jumpiness has other issues and drawbacks. The reason it's smooth in rFactor is because the other cars aren't bound to the actual physics. They just float on an interpolated line that roughly corresponds to what the opponent was actually doing. In LFS however the cars all continue to run on the physics engine, travelling along the path that they would've taken from the last received driver input. The jump occurs when the driver has changed his input between packets and drove to a different location than the physics calculated; this error is then corrected by warping the car to its actual position.

Another new thing learnt about LFS. Nice!
The only lag issues I've really noticed is sometimes when someone comes out of the pits or if you switch to a different driver view.

Too big a lag, and the person with the lag tends to drop off the server.
I entered a 200ms server today and didn't even experience jumping cars. Ping has nothing to do with lag. A guy on another thread proved this. (finding thread)
If I recall correctly there is a server-side option to choose how many packets for each car are sent to sync position. The higher value is set, the smoother the game is. Maybe the server you've been playing on had this packet amount lowered to save some bandwidth...
Quote from MadCatX :If I recall correctly there is a server-side option to choose how many packets for each car are sent to sync position. The higher value is set, the smoother the game is. Maybe the server you've been playing on had this packet amount lowered to save some bandwidth...

You know, this may make a lot of sense. Sometimes I race on a server dedicated just to games and I have no issues, probably because the use high settings. I see this issue on other games too, so it isn't confined to LFS.
Quote from Nitrous13270 :I entered a 200ms server today and didn't even experience jumping cars. Ping has nothing to do with lag. A guy on another thread proved this. (finding thread)

I agree. I didn't look for the thread, but this is my take as of why:

As long as the connection is stable the cars will have no more jitteryness then the minimum amount of jitteryness as LFS is programmed to have. But, high latency will be more prone to dropped packs by the nature of networking. Latency is cause by the distance and the amount of time the packets being sent have to be processed and reprocessed at routers or 'hops' on the network. In these cases the internet. Lag also has nothing to do with the speed of the line purchased. But like with latency consistency is key for multiplayer games. I would rather have a consistent 1,500kbps connection then a not so consistent 20,000kbps connection for gaming. Or even a 500kbps stable connection. Any ISP that sells you a 'gamers connection' as the best connection for gaming because of it's speed is taking advantage of the fact gamers spend fair amounts of money in internet gaming. It's marketing. And The more you press a modem for speed, the more likely it is to drop packets and become unstable.

With LFS high latency is not very noticeable as it is a racing sim. Unless of course it is very, very high latency. In a racing sim their is a certain amount of expectation by the driver because the cars have momentum and will continue to travel in a certain direction as they change direction either in acceleration forward, left, right and deceleration. The nature of a racing sim gives you the ability to predict better. But, sharp reflexes will still help you in a racing sim. Not saying they aren't a good thing.

In a shooter though you want to have constancy combined with low latency as razer sharp relexes are needed in the heat of combat. Unless of course you know how to run the map. This combined with reflexes is how the best FPS players win. You can use prediction, but not as much as you can in a racing sim as the movement in a shooter is more unpredictable due to how quick changes of direction can be as opposed to the natural physics of a racing sim.

Jay

**Edit. I would like to add that this is why people from all around the globe can be in one server at the same time and enjoy a good multiplayer racing experience. The luxury of the nature of Sim Racing far exceeds that of Shooters as most the time you try and get the best ping possible to compensate for the delay.
You may have a great ping to the server, but the other players might be a long way away. This will make the warp effect you see of them, worse. Try and race servers that attract local area players. 100mS servers should not result too much OTT warping cars unless you have a 'spiking' issue or ther other players in the server are from the other side of the world.

I personally prefer to race in servers that I can get anywhere from 0mS - 100mS max. Around 60mS is pretty damn good (Hobart>Sydney) about 1500kms and much over that I start to notice a little warping, but not too bad.

If I play CTRA that is just playable (360mS) But I really have to not battle for positions and just try and stay clear of anything moving. 360mS can cause a big ugly smash, but it is still playable - Just.

Try Shift-F8 to see the ping from yourself to other cars in the server. This can sometimes reveal things to you. And take notice of the latency bars. Each one represents each connection in the server, the same order as the connections list, press "N".

The green one is you, hold Shift+Ctrl to see the average latency for each player. If the lines are bouncing smoothly then the server is doing well handling all the connections.

Keep in mind the actual server might be overloaded and causing the warping.
Quote from JasonJ :You may have a great ping to the server, but the other players might be a long way away. This will make the warp effect you see of them, worse. Try and race servers that attract local area players. 100mS servers should not result too much OTT warping cars unless you have a 'spiking' issue or ther other players in the server are from the other side of the world.

[...]
If I play CTRA that is just playable (360mS) But I really have to not battle for positions and just try and stay clear of anything moving. 360mS can cause a big ugly smash, but it is still playable - Just.
[...]

Strange thing is there are many Brazilian servers with pings lower than 30mS (which have password so that only Brazilian players from the league can enter), but it's exactly in these servers that I notice the biggest lags and cars flying

But when I'm playing on CTRA (about 330~350mS here too) it's very smooth! I can't notice the car updating positions. Even when someone crashes or there are major crashes in the track, even battling for positions very close or when the cars hit each other, there's no lag and it doesn't cause the cars to fly or something, it works just like in single player.
There are some very rare hits that are are miscalculated, e.g. takes more hit than it should, but it's still not enough hit for flying, getting out of the track or damaging the car too much, it just loses some speed.

FGED GREDG RDFGDR GSFDG