Slashdot Log In
Most Impressive Game AI?
Posted by
Cliff
on Sat Mar 31, 2007 01:45 PM
from the never-the-same-game-twice dept.
from the never-the-same-game-twice dept.
togelius asks: "I have the feeling that when developers make the effort to put really sophisticated AI into a game, gamers frequently just don't notice (see e.g. Forza). Conversely, games that are lauded for their fantastic AI are sometimes based on very simple algorithms (e.g. Halo 1). For someone who wants to apply AI to games, it is very interesting to know what AI is really appreciated. What is the most impressive game AI you have come across? Have you ever encountered a situation where it really felt like the computer-controlled opponents were really thinking?"
This discussion has been archived.
No new comments can be posted.
The Fine Print: The following comments are owned by whoever posted them. We are not responsible for them in any way.
no (Score:5, Funny)
No, but I've rarely encountered games where it feels like my human opponents are really thinking, either.
Game where computer seems like it is thinking (Score:5, Interesting)
Parent
Re:Game where computer seems like it is thinking (Score:5, Funny)
That AI is smarter than most Earth leaders.
Parent
Re:Game where computer seems like it is thinking (Score:5, Interesting)
If the game has lots of bugs, bugs you might not normally see, the AI will suffer.
Oftentimes the A.I. of the game doesn't make the computer smarter. Making a game that's smooth and supports a good A.I., however, will make a much bigger difference.
With a game like chess, the A.I. program is huge and immensely sophisticated.
With a game like tic-tac-toe, you can make an A.I. that can't be beaten, simply because the game is simple and allows for that.
It's important to keep in mind that the actual A.I. algorithm can only accomplish so much. Putting Deep Blue into the seat of your tic-tac-toe opponent gives you the same result as the program you wrote that doesn't break a page.
That being said, a few more examples to look for for good A.I. that merges well with its game would be Kohan and Kohan 2. The AI in that game blew me away.
For an older game, check out emperor of the fading suns (you can get the full game for free) http://free-game-downloads.mosw.com/abandonware/p
I still have fun playing this one. It's interesting how the computer will actually send you money for nothing in the interest of making you like them more. There are a few other subtle details.
Incidentally I've heard that Gal Civ is based off of EFS, so if you haven't had a chance to check it out, enjoy.
Parent
Re: (Score:3, Insightful)
ummm, Galactic Civilizations II? (Score:2)
Re:ummm, Galactic Civilizations II? (Score:5, Informative)
I'm also very impressed with the AI in the original galactic civilizations. It does cheat at the higher levels, but up until that point (I think normal mode doesn't cheat either way) it's very impressive and it really does feel like the AI is thinking. More impressive is the fact that each major race has its own AI: not customized by arguments in the race, but specific, independent C++ code telling them what to do, written from scratch.
Parent
Re:ummm, Galactic Civilizations II? (Score:4, Informative)
Another very good one is freeciv. Freeciv may look much cheesier than the regular civilizations but in AI it surpasses it by far. I suppose it helps that it is developed by players of the game.
Parent
Re: (Score:3, Insightful)
Re:ummm, Galactic Civilizations II? (Score:5, Interesting)
That is very refreshing to see these days. I have given up on most PC games these days because of their copy protection systems.
Parent
Re:ummm, Galactic Civilizations II? (Score:5, Informative)
Parent
Of course... A Nethack pet (Score:2)
Come off as cheap (Score:5, Interesting)
Another way to look at it is if you think that the AI is learning patterns and adjusting for tactics.
That's been played out in many genres, the most recent to come to mind is the Stargate SG1 episode where a character must face a situation that adapts to his efforts and becomes impossible to beat since the game can react faster than he can and has a perfect memory.
It's a ballance that game AI must match, playability and difficulty.
Re: (Score:3, Insightful)
Re: (Score:3, Informative)
Re:Come off as cheap (Score:5, Insightful)
Writing an AI that makes the occasional "human error", or responds in a reasonable time is harder than writing the "best AI possible", but makes for a more believable (and of course, enjoyable (since who likes getting beaten all the time)) game experience.
Parent
Re: (Score:3, Interesting)
The most human AI would see patterns and adapt. The learning also plays a role, since just randomly playing out pre-programmed moves till one works leads to repetitive gameplay. The AI must have a very low level of options to piece together so it can make larger combinations that turn into tactics. The smaller each action is and the more actions it has to work with will let it find the best action. But that still doesn't mean that it has learned anything if it starts over with each situation. It has
Re: (Score:3, Interesting)
Targeting by calculating from internal data and perfect knowledge of the physics model, rather than analyzing screen output, is not what I would typically call "AI". Not all games are First Person Shooters, and FPS are not particularly good tests of AI since targeting is such a big part of them.
In simple, pure-strategy board games like Chess, the best AIs are only on par with the best humans. In more complex mostly-strategy games, like the various Real Time Strategy games, the AIs are hopelessly outmatche
Re: (Score:3, Informative)
Key features in that game:
Ctrl-click/double-click/box selection, and assignment of keyboard shortcuts (stuff we're familiar with in all games)
The ability to set postures like do or die, retreat at half damage, retreat at 3/4 damage etc (again familiar stuff)
Repair facil
Fact or fable? (Score:5, Interesting)
I never thought that the ghosts would be so complex!
Re:Fact or fable? (Score:5, Informative)
http://www.mameworld.net/pacman/patterns.html [mameworld.net]
Parent
Re:Fact or fable? (Score:5, Insightful)
To be honest, I've always thought that AI in computer games sucked. Games are usually made hard by having the bad guys have better fire power, shields, energy etc than you, or having loads of them against one player. It would have been a laugh, for example, to have a doom style game with one player against one computer bad guy, but have him be as smart as a human. Thankfully, online multiplayer games mean you are no longer restricted to whatever crap AI system the programmers manage to string together, although the problem has now shifted to dealing with people cheat - a problem which games programmers show no signs of being any less inept at dealing with than with AI.
Parent
Re:Fact or fable? (Score:5, Informative)
"AI : We wanted to integrate in our game the original AI behavior of the ghosts (those that were in the original Pacman game). Without AI, the game was not interesting to play, since a random behavior is too simple to play. Each ghost has its own personality: Shadow is the red ghost and it chases Pacman all the time, using a straight forward tracking algorithm. Speedy is the pink ghost. It is very fast but moves in a random manner. Bashful is the blue ghost: it is shy at the beginning and escapes from pacman all the time, but if Pacman approaches him to much, then it is not shy anymore and begins to chase him (Pacman is then chased by two ghosts at the same time...). Pokey is the orange ghost and is slow and moves in a random manner. "
Not as complex as the story that I read, but apparently they don't follow a pre-planned course.
Parent
Re:Fact or fable? (Score:4, Funny)
Parent
Civilization III (Score:5, Funny)
Re:Civilization III (Score:5, Funny)
Parent
Galactic Civilizations 2 (Score:5, Interesting)
Simplfy the game and the AI gets better (Score:3, Interesting)
The reason it's great is that there's simple rules to the game that the AI can know. There's been one point in the game where the AI got confused mainly because I blocked her in with a couple traps, but overall the Ai's abilities in the game are outstanding.
The important think to know about AI in games is it's not "AI". It's scripts or code that simulates scripts. There's no neural nets or anything else because we can't get the power for a neural net in an active game. In chess we can but then chess no longer is fun unless we tone down the "intellegence".
Some other great AIs are Gears of War (On insane they do great flanking maneuvers and such) Ghost recon (they really seem to know how to take cover and make it a challenge for the player to take them out. however the friendly AI leaves.... alot to be desired), Oblivion (watching random people walk around is pretty impressive, it helped build up that game.) and others, but there's none that make me think I'm fighting a real person.
There is a push to create truer "AIs" in games, Gran turismo created a way to train Drivers, Forza 2 is improving on it's drivtar system, Virtua fighter 4 had a way to teach an AI fighter, which was cool and indepth. But these are all "Scripts" taken from player experiences, not exactly AI. There's other games working on "true AI" but even then it's still toned down because we don't have the tools to make the driver "think" yet. It's just rail following and teaching the computer how to follow rails or when to break away from them.
I wouldn't say the molyeniux's games had great AI but they have good AI that at least learns a bit. Yet they feel like it's all you telling the game what to do, and it trying to figure out what you want it to do (and it fails) where as the Sims has interesting AI, but never feels real (mainly because the game never feels real).
So overall if you want to see good AI, look at simple games, expecting full 3d world simulations to have great ai is still a long way off but it's slowly coming. However this push for "graphics graphics graphics" won't help AI in the long run, but hopefully in a couple generations we stop worrying about graphics and work on AI and physics which seem to be more beneficial to the player then higher polycounts.
Re: (Score:3, Insightful)
Hmmm. If I write a neural net program, how is that different than what you call "scripts or code"? It's still just code.
And the best chess algorithms (which you seem to claim are "real AI") are just search alg
Re:Simplfy the game and the AI gets better (Score:4, Insightful)
What I really was trying to get across was a common misconception (one that stuck me when I got into a game company) that "AI" as it's taught in school is very different hen AI as it applies to most games. The biggest difference is most AIs don't learn, and most are pretty much just a script that doesn't change. We don't have the ability to throw away any cycles of the game so the AI tends to be highly stripped down to the point it's just "oh I see a gun, I'm going to react to the gun, how should I react to the gun, I'll do that." This is completely scripted to the point where you can tell what's going to happen if you point the gun at the person a second time or a third time. There's no "thought" or "intelligence" to the system, thought it might seem "intelligent"
A chess AI on the other hand evaluates all the options of what it can do and chooses a best option, the pruning is a form of "thought". A chess master will be doing something similar where he thinks of all his possible moves and then considers responses and so on which is effectively using game theory. To me that's actual intelligence even if it's not fancy.
The difference between a neural net program is it's code that tries to simulate the learning and thought process if you will, the code that AI in games use is just like I illustrated above. There's an "action" and the code quickly decides what's the reaction and does it. It doesn't try to evaluate too much because we don't have the cycles to do that.
Parent
Re: (Score:3, Interesting)
Counter-Strike AI (Score:5, Funny)
Friendly AI (Score:5, Insightful)
I don't play many games any more, but Halo 2 was one that I thought pulled ahead of the pack a bit. Friends that can drive vehicles was pretty cool (albeit not always the safest drivers...) allowing you to man the gun in the back. They also seem better at not running right in front of you when you're in the middle of launching a rocket, and also do little things like take advantage of available cover (or in other cases jumping up on top of said cover and getting blown to bits). Halo 3 is supposed to have even better AI for both friendlies and enemies, and that's one of the things about it I'm looking forward to.
Wesnoth (Score:3, Interesting)
Although it isn't that the AI is that well done, it is that the rule set is simple enough that an AI can follow it.
I've played Civilization, Heroes of Might and Magic and Masters of Orion, the trinity of TBS games. Although they were often very good, the AI could only win in all of them due to "cheating" of a sort. The reason was that the various different factors to be considered were behind the planning ability of an AI. For example, in Heroes of Might and Magic II, there were seven different resources that a player could collect. Often, towards the end of the game, even while it was badly losing, the AI would be running around trying to grab resources, and would lose because of it. In Civilization II, because there was so many different units and improvements to be built, the AI would produce useless units, or spend all their time building improvements to cities that were about to be captured. The algorithm for keeping track of so many factors is impossible to make in an AI. AIs can't understand what is relevant and what is not.
So, in Wesnoth, there is only one resource to be considered, gold. Damage is also a straightforward mathematical calculation. So with the simpler rule set, the AI can play in a relevant way. Not that the rule set is simple in the sense of easy, it has a few factors, but those few factors can be combined in intricate ways.
So Wesnoth has one of the better AIs in my view, although of course it can still be tricked and worked around, but then any AI can be.
Cheating (Score:5, Interesting)
Good, or good for the price? (Score:5, Insightful)
However, if we're talking about "impressive" AI, nothing I've seen in the gaming world can compete with Paradox's EUIII. Yeah, I know, each individual AI nation makes a lot of bonheaded moves. But the game is managing the armies, navies, economic, religious, colonial and foreign policies of up to 300 nations, every game day when a game year can go by in a minute or two, on a 1.9GHz processor. Considering the number of cycles and the amount of memory avaiable for each AI opponent, it's simply amazing to me. I really think that should be the basis of comparison, not so much the level of play the AI achieves, but the level of play it achieves with the resources available to each AI player. If nothing else, that standard makes it meaningful to compare old games against new ones.
F.E.A.R (Score:5, Informative)
Screw game AI (Score:5, Funny)
See point 23 [google.com]
The original (Score:5, Insightful)
It had the first bots that you could play against for hours and not even notice you were offline. I havn't encountered a more convincingly human AI in the dozen FPS games I've played since, including UT 2k3(which probably means that the UT maps were just easier to code for).
It's the only game where you can feel yourself increasing in skill over the course of a few days of playtime, and ratchet up the difficulty a bit and get the same kill ratio, without feeling suddenly overwhelmed by perfectly aimed headshots.
Civilization IV (Score:3, Interesting)
Perfect Dark N64 (Score:3, Interesting)
I know the best AI ever! (Score:5, Funny)
Best game AI? (Score:4, Funny)
The Thief Series was Groundbreaking (Score:3, Interesting)
There are over 400 Thief series fan missions. Last night, I played "Ominous Bequest"
http://southquarter.com/?p=131 [southquarter.com]
One level change for 6 hours of gameplay! Yes, Thief 1 and 2 graphics are quite dated, and low-poly, but if you can forgive that, the gameplay and atmosphere compensates for it.
Lately, there's been a reinsurance in Thief 1 and 2 add-on missions. There's a updated version of 680mb Thief2X add on. Missions like "Ashen Age," and a "Night in Rocksburg" have breathed a little life into T2 visually.
http://forums.eidosgames.com/showthread.php?t=552
http://southquarter.com/?p=131 [southquarter.com]
Someone is working to refresh the Thief Series Engine, but the source code would help. I wish that Eidos would release the source code--for an eight year old game.
http://www.ttlg.com/forums/showthread.php?t=10228
Far Cry (Score:5, Insightful)
The really sad part was when, halfway through the game, they switched from "smart" soldiers, to Doom-esque mutants who just ran straight at you. Ruined that game for me.
Operation Flashpoint (Score:3, Insightful)
No matter how often you replay a mission, it will always come out totally different. This comes in large part from the very open nature of the game, namely there are basically no rooms, its all just one huge outdoor environment and both you and the enemies can go basically wherever they want. It also comes from the way the missions are designed, there are no soldiers that jump out from behind a rock to shoot at you, instead the enemy soliders just follow their routine, they walk their paths, drive a convoy along the road or whatever they have to do right now. Thanks to the large area, they don't have to walk on a stupid 10 meter long path and then turn around to repeat it over and over again. This all leads to a very realistic feel, because all the limits of classic FPSs are removed. Its also not you against 100 other, but often more like you + 5 team members against 10 other, so its a much more even match. In Operation Flashpoint the player is also completly equal to the enemy, one good targeted shot and you are dead, no 100% health that slowly goes done while enemies die on the first hit.
Another aspect that is noticeable in Flashpoint is that there is a very clear difference between the state of the enemies, you can easily tell when they are on patrol, when they are attacking you and when they are searching for you. If you shoot at them they will notice it and react appropriately, this also makes it easy to tell when they don't notice you, i.e. you can hide rather well, a tank won't see you when you are crawling directly infront of it, etc. As a player its simply easy to tell what the enemy is currently doing, since the animations and behaviors are rather distinct for each of the actions.
Last not least Flashpoint is also a game where you need your teammates and where they are not just stupid cannon fodder. Most of the time your teammates can take very well care of themself and you don't have to babysit them like in some other games (HalfLife2...).
All that said, the AI in Flashpoint is far from flawless, it can often be a nightmare to get your group to mount a vehicle or get to a certain point, they will do what you want, but when they crawl around for a minute before entering the vehicle it can get pretty annoying. But overall Flashpoint really is among the best, it is however not just the AI itself that does the job, but the overall game design that threads players and enemies basically the same, it also helps a lot that the whole gameworld is interactive, if you see a tank, then you can drive it, there are no artificial barriers, no pre-scripted events that happen outside of normal gameplay rules. That scripting that is there blends perfectly into the normal gameplay.
Re: (Score:3, Insightful)
Creating difficult opponents is just a matter of reaction and aim. They can just stand blatantly still and fire at the very nanosecond you reveal yourself.
Good AI is the kind that retreats when it is outnumbered, interacts with its comrades and the surroundings, explores and interacts with the mess that you yourself may create and so forth.
Re: (Score:3, Interesting)
All of the AI players have their own special abilities, which fall into two basic categories. Mario and Luigi get invincibility, everyone else gets a tossable/droppable item (Banana, Fireball, Shell, etc
Re: (Score:3, Interesting)
Had a similar depressing experience in my class on AI. The task was to build a neural network that could guesstimate the sex of a first-name. A quite complex neural net, trained on 300 random male and female names could thereafter guess the correct sex of a name about 65% of the time.
Which seemed impressive until someone pointed out that a trivial table-lookup of the most common 100 fem
Re: (Score:3, Interesting)
It's still AI if those triggers are hardcoded or based on statistical analysis.
It *is* intelligent for an NPC to realise a grenade was thrown by the player into it's general area, and throw it back at the player. That's not to say it shouldn't be ranked highly or that it is a crappy AI.
If an enemy hops over a wall next to him for cover it's the enemy realising that he needs cover and there is an easily hoppable wall. He could just as well duck behind a barrel, but