Interpolation problems? (Jumpy players)
by Robert Nall · in Torque Game Engine · 02/19/2004 (1:01 pm) · 122 replies
Bare with me here as I attempt to describe this, heh.
Basically, for any client connected to the game (including the super/server-client) the engine seems to have trouble positioning the other clients in the game. So say you're driving around a track and another racer shows up in your view, they will appear to be spastically warping around their general position. It's as if there were serious lag on the other player, except that nothing else is showing signs of lag. Now if you head over to that other player's screen, you'll see the opposite. His car is moving just fine and the first player's car is all over the place.
I've looked for this in the starter.racing package and not noticed anything. I seem to recall reading somewhere that the speed of an object can affect it's interpolation negatively in the TGE, might that be what's going on here? I'm also using a resource that seperates the camera from the control object, so I suppose that could be causing me problems as well.
So I was basically wondering if anyone else has run into this and knows what it is. If not, I guess I'll have to go test it more throroughly myself, heh. I just have other things on my plate right now and was hoping someone else had already run into and solved this problem before. ^_^
Thanks,
-Rob
Basically, for any client connected to the game (including the super/server-client) the engine seems to have trouble positioning the other clients in the game. So say you're driving around a track and another racer shows up in your view, they will appear to be spastically warping around their general position. It's as if there were serious lag on the other player, except that nothing else is showing signs of lag. Now if you head over to that other player's screen, you'll see the opposite. His car is moving just fine and the first player's car is all over the place.
I've looked for this in the starter.racing package and not noticed anything. I seem to recall reading somewhere that the speed of an object can affect it's interpolation negatively in the TGE, might that be what's going on here? I'm also using a resource that seperates the camera from the control object, so I suppose that could be causing me problems as well.
So I was basically wondering if anyone else has run into this and knows what it is. If not, I guess I'll have to go test it more throroughly myself, heh. I just have other things on my plate right now and was hoping someone else had already run into and solved this problem before. ^_^
Thanks,
-Rob
#2
-Rob
02/19/2004 (1:48 pm)
Thanks, at least I know it was there from the start and it wasn't anything I did. Now to find a solution . . .-Rob
#3
02/20/2004 (11:30 pm)
The car _ought_ to work just fine. Does the demo produce this behavior? Was it over a LAN? :)
#4
In my case, Czar and I were playing together on a server I was hosting on a 3 Mbps connection. Torque runs just fine on it, and when screwing around with players and just fragging each other we have no problems at all. But we experienced a lot of crazy jerking, warping, lag, and other issues when trying to race each other with the buggy.
This was on the net, not LAN. His ping to me was 32 ms so I doubt congestion or latency was the issue. Plus when you factor in that we raced each other quite a few times on several different nights, I can comfortably say that I gave it a fair amount of testing. Trust me when I say we try to get to the bottom of everything and we always check the most obvious first.
02/21/2004 (12:06 am)
Ben, the car does work just fine. Just not when your run it in multiplayer(although I have not personally tested the car in the last two months or so).In my case, Czar and I were playing together on a server I was hosting on a 3 Mbps connection. Torque runs just fine on it, and when screwing around with players and just fragging each other we have no problems at all. But we experienced a lot of crazy jerking, warping, lag, and other issues when trying to race each other with the buggy.
This was on the net, not LAN. His ping to me was 32 ms so I doubt congestion or latency was the issue. Plus when you factor in that we raced each other quite a few times on several different nights, I can comfortably say that I gave it a fair amount of testing. Trust me when I say we try to get to the bottom of everything and we always check the most obvious first.
#5
02/21/2004 (11:48 am)
Ok. Something I'll have to put on the "to check out" list, then. Thanks for being so thorough. :)
#6
The AI vehicles are controlled using a class derived from AIConnection, that is set up to control a WheeledVehicle; much like the AIClient controls a Player.
So I can be running a race with only my own super-client and a single AI racer all on the same machine, and the AI racer will frequently 'hop' up in the air while moving along.
03/11/2004 (2:09 pm)
By 'true clients' I mean that the AI players are set up using an AIConnection.The AI vehicles are controlled using a class derived from AIConnection, that is set up to control a WheeledVehicle; much like the AIClient controls a Player.
So I can be running a race with only my own super-client and a single AI racer all on the same machine, and the AI racer will frequently 'hop' up in the air while moving along.
#7
03/28/2004 (5:17 pm)
Odd. I'm hoping these issues can be resolved. They scare me. Mayhem 2090 is 100% a vehicle game, so this will be a huge issue for us.
#8
03/28/2004 (8:25 pm)
Have you tried turning up the update frequency/size?
#9
04/01/2004 (9:12 am)
Where is that variable located?
#10
good luck!
-s
04/01/2004 (3:05 pm)
Clientprefs.ini or whatever the big ol pref file is for the client. good luck!
-s
#11
Thanks,
-Rob
04/01/2004 (3:54 pm)
I was just looking through the scripts and I don't see anything that references an update frequency or size. The only thing I noticed that was net related was a Pref::Net::LagThreshold. Should I be looking in the engine somewhere?Thanks,
-Rob
#13
Thanks,
-Rob
04/02/2004 (10:08 am)
Aight, I found those variables, but only in the pref.cs file. Where are the defaults set for these?Thanks,
-Rob
#14
04/03/2004 (12:52 am)
Try grepping the source for "PacketRateToClient"... 
#15
You can find some details on those Net prefs here, thanks to Joel Baxter.
I'm sorry I don't have more help to offer. I'm not yet familiar enough with Torque's network functionality nor vehicle code to tell what's up. Messing with the net settings might be necessary/good, but, off-hand, it seems like a bit of a band-aid solution.
I am in the middle of a project, and kinda sick, but I'll try to look into this a bit.. :\ Hopefully someone else will offer a solution rather than you having to wait around for me.
04/04/2004 (6:20 pm)
Dave,You can find some details on those Net prefs here, thanks to Joel Baxter.
I'm sorry I don't have more help to offer. I'm not yet familiar enough with Torque's network functionality nor vehicle code to tell what's up. Messing with the net settings might be necessary/good, but, off-hand, it seems like a bit of a band-aid solution.
I am in the middle of a project, and kinda sick, but I'll try to look into this a bit.. :\ Hopefully someone else will offer a solution rather than you having to wait around for me.
#16
I talked to Mark about the problems in this thread, and he wasn't sure what's going on either. It'll take some more details to figure this thing out. Is it possible to have your programmer add some thoughts here?
Vehicles normally work well in multiplayer. Have any modifications been made to the core vehicle or network code in your project? What datablock settings were used? Etc. I'd recommend having your programmer step in with any and all relevant information (that you guys are comfortable with revealing).
Just to note, I obviously can't guarantee that any of us will have the time to try to solve this problem, but having more info would help. And if one of us in the office doesn't figure it out, maybe someone in the community will be able to.
Btw, your game looks pretty cool. :) I especially like that screeny in the city street.
----
Additional Q's:
For the purpose of testing, have you tried slowing your vehicles down and checking whether that has any impact on the behavior?
04/06/2004 (2:17 am)
Dave,I talked to Mark about the problems in this thread, and he wasn't sure what's going on either. It'll take some more details to figure this thing out. Is it possible to have your programmer add some thoughts here?
Vehicles normally work well in multiplayer. Have any modifications been made to the core vehicle or network code in your project? What datablock settings were used? Etc. I'd recommend having your programmer step in with any and all relevant information (that you guys are comfortable with revealing).
Just to note, I obviously can't guarantee that any of us will have the time to try to solve this problem, but having more info would help. And if one of us in the office doesn't figure it out, maybe someone in the community will be able to.
Btw, your game looks pretty cool. :) I especially like that screeny in the city street.
----
Additional Q's:
For the purpose of testing, have you tried slowing your vehicles down and checking whether that has any impact on the behavior?
#17
With MiniOne Racing we are in the same situation as yours.
We managed to reduce AI jerkness by playing with Packets prefs.
But one of our main problem is still here: collisions detection between AI/Networked-vehicles and Players-Vehicules. It seems to us that there is some sort of latency between vehicules drawn (AI) and his bounding box. The faster the vehicles go, the stronger the latency is.
The local player do not have this problems...
04/06/2004 (11:22 am)
I can confirm the problem.With MiniOne Racing we are in the same situation as yours.
We managed to reduce AI jerkness by playing with Packets prefs.
But one of our main problem is still here: collisions detection between AI/Networked-vehicles and Players-Vehicules. It seems to us that there is some sort of latency between vehicules drawn (AI) and his bounding box. The faster the vehicles go, the stronger the latency is.
The local player do not have this problems...
#18
What code release are you guys working with? HEAD, or something previous? Have you made any code changes or used any unincluded resources?
If you don't mind, it might be useful to see some of your datablock declarations.
Let me know.
04/06/2004 (1:30 pm)
Do any of you notice a speed threshold at which the latency problems begin to appear? Or does it happen all the way down?What code release are you guys working with? HEAD, or something previous? Have you made any code changes or used any unincluded resources?
If you don't mind, it might be useful to see some of your datablock declarations.
Let me know.
#19
04/06/2004 (1:39 pm)
Call me stupid, but how are you guys getting those bounding boxes? In the world editor? Is this only occuring wiht AI vehicles? If so then we should be all set. We have no AI vehicles. Our game is totally multiplayer and has no bots.
#20
Here one of our datablocks:
www.frogames.com/race.cs
We're using the HEAD of 04/11/2004. We're also using aiclient.cc to manage the AI vehicles. We made some changes to the engine but I'm pretty sure we can reproduce the problem on the current HEAD with little changes.
@John, yes we're using the world editor.
I can't remember exactly how it do on multiplayer, I can't test it the evening... We'll try that next days.
04/06/2004 (2:20 pm)
"latency" seems to occur every times the vehicule moves but it's not visible at low speed.Here one of our datablocks:
www.frogames.com/race.cs
We're using the HEAD of 04/11/2004. We're also using aiclient.cc to manage the AI vehicles. We made some changes to the engine but I'm pretty sure we can reproduce the problem on the current HEAD with little changes.
@John, yes we're using the world editor.
I can't remember exactly how it do on multiplayer, I can't test it the evening... We'll try that next days.
Torque Owner Gonzo T. Clown
We came to the conclusion that GG may not have had multiplayer gaming in mind for the car. We also figured it most likely had to do with the cars collision with the terrain being that it has 4 tires and a body to track at all times.
That's all speculation, sorry I don't have more to offer.