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Neuro-Reckoning May Reduce MMOG Time Lag

Posted by Zonk on Fri Oct 19, 2007 08:45 AM
from the would-probably-help-in-karazahn dept.
Hugh Pickens writes "Time lag can cause some very strange behavior in massively multiplayer online games when players' actions onscreen become slow and jerky. New techniques are on the way to reduce the problem of lag time in MMOGs when a player's computer can't keep up with changes in a shared online world. Games like Quake use a technique called dead reckoning and while traditional dead-reckoning systems that assume that a game character will maintain the velocity and direction that it has at the moment an update is sent to all other participating computers; dead reckoning works best for movement and shooting and less well for erratic actions such as interacting with objects or with other players. Read the abstract of new technique called 'neuro-reckoning' that may improve the predictive process by installing a neural network in each player's computer to predict fast, jerky actions."
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  • by KDR_11k (778916) on Friday October 19 2007, @08:57AM (#21039967)
    Since MMOs involve lots of repetitive actions that can easily be automated it shouldn't be too hard to predict what the player will do. OTOH this is kind of an admission that MMOs are so dumb that players are pretty predictable. I guess that's why I'm not playing an MMO currently...

    (cue the Eve spam)
    • I can see it now, lag hits - and in the interim you watch astonished as your character kills another rabbit and harvests it's spleen for sale back at town. The next gen of this technology will have your character spamming group channels for heals.
    • I kinda doubt that it works that well.

      For starters, let's look at the plain old interpolation. I see it kicking in all the time in MMOs (e.g., WoW), and players seem to run ahead for half a mile until the game gives up and disconnects them. Or spend the next 5 minutes running in place against a fence.

      Let's take just that one simple action: running. How do you know where I'm going to interpolate it right past a second or two. If I arrived at, say, Westfall (to give a low level example that anyone who's ever
      • The article is not talking about that kind of intelligence. They are talking about split second intelligence. They are talking about being about 500 msec of packets being the main scene...
          • Re: prediction (Score:3, Informative)

            by Anonymous Coward

            if in those 500 ms it guessed that my Priest hit his psychic scream (i.e., fear) spell and he didn't, you're at a disadvantage

            It won't. (Aside: But if it ever does, then it would mean the server decided you should have done it, and it did it for you without your consent.)

            These predictive models are for data compression [wikipedia.org], where the cost of encoding a given bit is based on the log of the probability of that bit occurring. For example, if it's 50:50, then it costs you 1 bit either way. However, if you can g

      • by rickwood (450707) on Friday October 19 2007, @10:52AM (#21041713)

        If I arrived at, say, Westfall (to give a low level example that anyone who's ever played WoW will have seen)
        For the Horde, you insensitive clod!
        • Yes and no.

          First of all, if you talk about something that actively takes control of my character for me, to do all that stuff, you're talking a bot. Which is against the TOS on any MMO, and can get you banned on the spot. I very much doubt that anyone will implement one right in the client, as some next great feature.

          Second, those exist already. See, WoW Glider.

          (Note that I'm not actually advertising using it, and if anyone gets banned using it, I'll cheer for the Blizzard employee that banned them. Just us
    • i can see it now:

      "the neural net has figured out that i'm a gold farmer, so all i have to do is unplug my net connection and it continues smacking down elves even while i'm at work!"
  • by threaded (89367) on Friday October 19 2007, @08:57AM (#21039973) Homepage

    ...to predict fast, jerky actions.
    Sorry, but that has to be the QOTD, made me ROFL.
    • Sorry, but that has to be the QOTD, made me ROFL.

      Good. Be sure to fill out a TPS report.
  • Looks interesting, but using Neural nets would require massive amounts of computing power, compared to the more simple dead reckoning. Or at least that was the case when I worked with neural nets 12 years ago - better/faster algorithms might have been made since then.

    But then again, the CPU's are so fast today, that it might not be an issue at all.

    • Re: (Score:2, Insightful)

      According to the abstract anyway, "Our proposed neuro-reckoning framework exhibits low computational resource overhead for real-time use..."

      Twelve years ago I had a Pentium 60Mhz that could barely play MP3s without skipping. CPU architecture improvement and especially multi-core processing would probably leave plenty of room for short scale neural network movement prediction.
  • ... if the Neural net can predict my next move, just let it make it for me. Send my bot out to farm Karazhan for me while I watch the hockey game. Oh wait...
  • by 140Mandak262Jamuna (970587) on Friday October 19 2007, @09:10AM (#21040093) Journal
    To control the automatic weapons firing at aircraft in south africa!
  • Uh. (Score:3, Informative)

    by Wilson_6500 (896824) on Friday October 19 2007, @09:10AM (#21040097)
    OK, so shooting games, where you traditionally need to move as erratically and unpredictably as possible to stay alive and kill effectively, are well predicted by dead reckoning; MMOs, where you generally move directly from one beast to the next waiting for your skills to kick in, are not?

    If I had to guess, the real problem is probably that commercial, hugely-trafficked MMO servers don't want to send as much data to each client as some guy's dedicated server in his basement that's only visited by thirty-two clients at a time. This probably results in the player and server updating each other less frequently.

    Still, since in the MMO there are usually pretty predictable things the player will be going to next (the item on the ground, the nearby mob, the NPC in his path), maybe this will work well after all.
    • Indeed; one day soon, Chinese goldfarmers will be freed from the slavish burden of even running their own scripts. Instead, the server will simply predict what speeds hacks they would have run, and award them the gold without the tiresome necessity of actually having to receive packets from them.

      Ultimately, our own machines will be able to predict the actions of everyone else, and we will be able to play multiplayer games together completely on our own. The circle will be complete.

  • Quake's Lag (Score:2, Interesting)

    Would it be akin to Quake's lag or to the later versions of Quake? I never cared for how lag was "felt" following Quake I. QW through Q3 (I haven't played any others) all would make you feel like you weren't lagged at all but then suddenly you would show up dead as you caught up to real time. At least with Quake I you could "feel" the lag and make the proper adjustments.
    • Re:Quake's Lag (Score:5, Interesting)

      by ejito (700826) on Friday October 19 2007, @09:39AM (#21040477)
      That actually has more to do with latency than number of updates. Latency determines how long until you feel an action from that was updated to the server. If everyone has 200ms ping, then someone shoots you, and that shot is updated to the server 100ms later, then you feel the hit 100ms after that, for a total of 200ms. Within that 200ms, you'd have ample time to hide behind a box or the corner of a wall, but the server would still say you were hit (because 200ms ago you weren't behind that box or wall on your enemies computer). This retroactive update is how modern systems work, and it reduces apparent shooting lag.

      Sidenote: This began the misconception that lag time benefited the lagger, or that laggy players lag the whole server, neither of which is true. The quicker your ping time, the faster your shots or actions will register on the server. If a high ping bastard and low ping bastard shoot each other at the same exact moment, the LPB will have his shot register first, and the HPB will die.

      Originally, shots and hits were always done actively at the time it reached the server. So if you had 400ms ping, you'd see your gun shoot 400ms after you fired it. This made lag almost unbearable for most high ping players, because if they shot at you, they'd almost always miss, because by the time their shot registered, you would've moved out of the spot you were standing a split second ago.

      As for the article, it's dealing solely with player movement on MMORPGS, which is determined by the rate of updates (how many packets get sent out per second). Player action updates are always triggered at the time of action (such as casting a spell), however, movement is an ongoing process. Basically your client updates the server around a dozen times a second with position and velocity information, because of your movement. However, it always assumes you'll stick to that velocity (moving forward? dead reckoning predicts you move forward some more) in between updates. If you deviate from your predicted movement along a velocity, you need to send an update to the server. This new method will predict what movement you'll take, rather than always assuming a straight line from your current movement.

      My student ACM account doesn't have subscription to access the article, so I'm not entirely sure, but this is my take on what it does:
      For instance, if you're moving forward, and there's something in front of you, the neural net will attempt to determine that you'll probably move in a different direction, and send that as your predicted velocity. If it turns out you don't move that direction, you'll simply have to send another update. If you do move that direction (which statistically you should), then there will be no need for an update, thereby saving bandwidth. These predictions and updates happen at a rate which makes it seem like your player is moving smoothly, when in reality, there's a bunch of micro deviations and stuttering.
  • The results: "First post!" "Step 1: Teach neural network to farm gold. Step 2: ??? Step 3: Profit!" "In Soviet Russia, you predict the actions of neural networks!" "I for one welcome our neural network overlords" "But does it run Linux?" "Imagine a Beowulf cluster of these!"
  • If you are lagging the server will switch you to a NPC until you packets get in. It is funny how academics like making things seems more complex then they actually are. Verses other way which generally keep you on your current path, which is easier to program.
  • Old news (Score:4, Funny)

    by Nutty_Irishman (729030) on Friday October 19 2007, @10:42AM (#21041521)
    Weren't we just reading about the beta test yesterday? Robotic Cannon Loses Control, Kills 9 [slashdot.org]
    • I would imagine that it can't be any easier than hacking the current dead reckoning implementations.
    • Re: (Score:2, Interesting)

      Well it's a short step between what you propose and things like aim-bots. The advantage I see for this type of research is not improving my play, but improving bot play. I haven't played recent games, but in UT2004 the bots can hit you with a hit-scan weapon from across the map (assuming their difficulty is high enough), but they are tactically stupid. But even besides this, there are very short term predictions of human movement that the bots don't pick up on. An opponent that has been hit a few times will
    • If the computer is going to predict my next move, I might as well let the computer play the game. If the algorithm is using a neural network, the computer will become just like me as time passes. The main difference between a good player and a normal one, is the difference from the nominal behaviour. Thus making this method of uterly useless.

      Your computer doesn't predict what YOU do because it can see it in real time and has no need at all to know what you're going to do in the future. Your computer, however, has to predict what THE OTHER players do when your server connection is bad and the information about what others do around you is coming too slow or not at all. Thus, not exactly useless.