Limite number of online cars

I understand there is some CPU limitation due to AI in offline mode.

Please, leave free the amount of cars in multiplayer mode. Let the community with the evolution of hardware define the limits.

If possible, put the cars in the garage, so each garage will have 2 cars, which will allow to double the amount of cars per box, equal to netkar pro, rfactor, gtr2, etc.

 

I agree!

 

would not it be an option to limit how many cars are visible on the track? only for example, 15 front and 5 behind, taking 45 cars on the track.

 

During the normal course of a race, as the grid gets spread out, the number of visible cars on the track is often already drastically reduced. However, you still have to run the physics on those AI that are not visible and, since they're running the same level of physics as the player (as opposed to a simplified model), it's the CPU which is the limiting factor, not the GPU.

 

I'm thinking, is it possible to add a kinda LOD system to the AI related handling and physics calculations? For AIs who racing far from the player, you just turn down the calculation rate of them.

 

Generally, the point of having the AI not running on a simplified physics model is to ensure that they're racing by the same rules (i.e., they're not somehow faster in certain situations - in the wet, capable of taking unrealistic lines, not as affected by curbs, etc.).

Having them run on a variable physics model that decreases in complexity as they increase their distance from the player (which would seem to swing wide open the door to significant rubber banding) arguably defeats the purpose of them even using a more complex physics model at all while in close proximity, at which point they might as well save the CPU cycles and have them run entirely on the simplified model.

 

But the question is about playing online when there isnt that ai overhead. Is it then possible to run more cars.

 

Yea, that'd be ideal.

My comments were just in response to those about the AI. Well, at least, I thought that the comment in regards to reducing the number of cars visible on the track was regarding AI, though now I see that that poster was the same guy who started the thread so...

 

Please, let's leave artificial intelligence out of this topic.

The subject here is the amount of cars in online mode.

 

What's really the difference between same number of cars in single player with AI and multiplayer in terms of fps? Your pc will still have to run the physics of all the cars same as in single player. 24 cars in MP and 24 cars in SP will give you the same fps. Or has anyone did any tests in AC and came with the result that you get more fps online compared to same number of cars in single player?

 

I would assume that in MP the physics for a car is only being run on that player’s machine and then just its location is shared with the other players.

EDIT: …well probably its location, trajectory and physical state. I’m sure others have a better handle on how it’s actually implemented.

 

Ooh, a somewhat ‘out there’ idea just popped into my head. I heard on the grapevine that Kunos are a little bit busy at the moment, but theoretically could other player car positioning be improved in MP through a hybrid AI/player positioning system? I don’t know at what frequency position updates are transmitted, but with dodgy network connections those updates don’t always turn up as smoothly as you’d want. I presume AC just interpolates missing updates to keep the cars moving when network data doesn’t turn up on time, which can lead to cars warping around or just straight shooting off track, only to teleport back on once the connection is re-established.

Instead of a simple linear interpolation (which is what I’m guessing we already have), could your own PC use AI to more intelligently interpolate where nearby cars should be?

 

Offline could be impossible to achieve 60 cars like in the 24 hours of Spa (I personally dont want them to dumb down AI physics). But if there is a possibility of doing it online, I think it deserves the effort.

Of course 30 cars are more than enough from the gaming POV. But one of the things that makes 24 hours of Spa so special is getting an absurd number of cars on the track (LeMans has the same number with twice the lenght) so the traffic is huge.

 

Your CPU is not running the physics for other players in multiplayer.

 

Why wouldn't it? You also need the client side physics to interact with the other players, so it simulates all the other cars. The server isn't streaming to your pc the physics, the server simply just runs the game same as you, with the extra thing that is the increased bandwidth-internet usage, which in the case of the client, he only uses the internet for himself, not for all the players, but the server needs to use the internet for all the players connected to it. The overhead can't be just the game graphics that affects the fps in multiplayer, but also the physics of the entire game (track and cars).

 

You sound very sure about how it works. Have you got a citation for any of this? (I don’t understand what you are saying about the networking btw.)

I still don’t understand why the physics would need to be calculated on more than one PC (sounds very wasteful to me), perhaps for collisions but I don’t see why full physics for the opposing car would be needed to be calculated to be able to model a believable reaction of your own car in a shunt.

 

Then how do you explain that running a full grid in AC's multiplayer is as heavy as running it against AI cars? AC is still a heavy CPU game online as offline. But I'm going to try to test for myself tonight and double check what I've been saying so far.

About the networking, when a computer is used as the server for people to play online, that pc is using more internet bandwidth compared to each individual client connected to it. You can also see this for yourself when you configure the server for AC on your own pc, the more cars you add more upload bandwidth you need to have.

 

I haven’t noticed that myself (I’ve only had CPU usage warnings in SP) but I could speculate that it’s the networking code that’s consuming a similar amount of CPU time. But either way, I don’t think this sort of discussion is a great use of either of our’s time, as there’s clearly a right answer, which hopefully the Kunos gods will bestow upon us. Or that someone else can cite?

I’m not really sure what this is relevant to, but thanks for taking the time to clarify it.

 

I tested moments ago this, and I seem to have at least 10-15 more fps in multiplayer during race countdown, by trying to replicate the same conditions in single player. I entered in full/almost full servers. In cockpit just looking in front, with graphic settings all low, post processing turned off and mirrors to normal. Then during the race it wasn't easy to keep track of fps, but the impression I got is that more fps online, with higher maximums.

The thing in single player is that you need to calculate AI for all the bot cars. But online your pc doesn't have AI calculations to do, only physics of the cars and game. So I think that's where the fps difference is from, that AI calculations take more performance and is non existent online. If your pc wouldn't calculate physics for all the cars in multiplayer there would be crazy differences in fps between online and single player.

So about the OP, I agree to give more slots for players to join and only have the "24 or 30" limit in single player. Is possible to have better PC performance online than in single player, and very big grids online seem to interest quite a lot of people that are into simulating certain real life races. But hopefully tracks with more pits come natively, of course to a limit, but more, so that players don't have to install mods for this thing to play in regular servers that want larger grids.

 

I can run 50 AI and more. I already tried 59 AI at Nords but the issues I have are with the difficulty AI have to navigate with so many cars. With 59 AI the accidents between AI are recurrent.
From what I witnessed up to 45 AI cars are able to navigate without major accidents and it is still possible to race with up to 50 AI cars.

Here are two examples with 47 and 49 AI cars: