Most Impressive Game AI? 398
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?"
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.
supreme commander (Score:1, Interesting)
Fact or fable? (Score:5, Interesting)
I never thought that the ghosts would be so complex!
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.
Warcraft III (Insane!) (Score:2, Interesting)
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)
Game where computer seems like it is thinking (Score:5, Interesting)
Game AI? Why bother! True AI has been solved. (Score:0, Interesting)
So-called "Game AI" is not even AI. It is just s few fancy tricks to make the game program look, but not actually be, a little bit smarter.
Mind.html [visitware.com] recently became a True AI that reveals the deep thought process in a tutorial display mode. You can interact with the AI Mind and watch it thinking, as spikes of excitation spread by associative tag from concept to concept in the knowledge base of the genuine artificial intelligence.
Mind.Forth AI for robots [sourceforge.net] is written in Win32Forth for installation in autonomous mobile robots and has spawned at least one independent offshoot on the Web as the true AI evolves and speciates into multiple branches of live-or-die AI in the Darwinian jungle of survival of the fittest.
Franks AI Mind [aimind-i.com] is the "son-of-Mind.Forth" AI with advanced features such as the ability to send e-mail and to read Web pages.
Civilization IV (Score:3, Interesting)
Perfect Dark N64 (Score:3, Interesting)
Falcon 3 (Score:2, Interesting)
Re:S.T.A.L.K.E.R. (Score:1, Interesting)
Even better is when youre wandering through a deserted trainyard late at night, only to realise that youre being hunted by a mutant on the other side of one of the platforms, creepy.
Re:Kart Racing (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) which they can use repeatedly.
It's not the same kind of cheating when a car mysteriously catches up to you at seemingly supersonic speed. In the former case, it's an obvious game mechanic. In the latter case, they're trying to be subtle about it and use it to cover up AI weakness, hopefully without you realizing that they're doing it.
Re:Come off as cheap (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 to have some sort of loose pattern recognition to see similar situations and apply the most likely solution.
Add all these things to an ability to totally screw up and you'd have a good AI.
Re:Perceived Intelligence - Simple is better? (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 female and male names, and random guesses for everything else is enough to reach about 70-80% (depending on the country the names are from, some countries have more variation than others) and even something as simple as "if ends in a, guess female, otherwise guess male" is enough to reach similar "accuracy" as the neural net.
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.
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.
Re:Perceived Intelligence - Simple is better? (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 the barrel may be made of soft shitty wood, the wall is nice and made of brick. It makes an education decision just like we do. They may well be SCRIPTED.. if near wall hop over wall else if near barrel duck under barrel else if player is actually in effective firing range, run the hell away else sit there and taunt them into the minefield..
Think of your thought process when you would be in the firing line and you have the choice between ducking behind a worm-riddled barrel to avoid gunfire, or a solid brick wall that you can hop over. How many seconds does it take? Can you remember every microdecision you made? No, you think "ohshit I'm being shot at" and probably duck behind the barrel under stress, when it starts to splinter then you scramble over the wall and realise you dropped your gun hopping over the wall..
Does that make it crappy AI that it did not break out scientific analysis of the situation and count variables or do complex physics?
Re:Come off as cheap (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 outmatched, and the difficulty of player-vs-computer scenarios is typically adjusted by how huge a head start the computer is given, or how much it is allowed to cheat in various ways.
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
Re:Civilization III (Score:2, Interesting)
Re:Simplfy the game and the AI gets better (Score:3, Interesting)
I can't say I buy your neural net deal either. At least not as a distinction between 'real' and 'non-real'. Will certainly agree in your examples there is a distinct split between computationally expensive and computationally cheap ways of determining courses of action for a computer program. But no "real" AI exists yet, that is no Turing test capable AI... neural nets or no neural nets. I think the point the other response was trying to point out is that regardless of the method used to simulate intelligence (static script vs adaptive code) the important factor in determining if something is actually artificially intelligent is generally agreed to be the Turing test. That is in interaction with humans it is impossible for a human to distinguish if the responses of the machine are from a human or not.
Frankly, 'real' AI from something like neural net code is not something game companies desire at all (computationally expensive or not). The problem is such code is by its nature un-predictable because any such system of learning/mutation has to be based on the unpredictable input of the player. A game which is unpredictable is bad from an investment standpoint because you don't know what it will do or how it will respond. Thus deterministic scripts that can be relied upon to act in a consistent way beneficial to the game are generally far more desirable. Not to say I don't want to see it come to be... just that the likely hood of seeing serious work along these lines is pretty slim right now barring some kind of breakthrough.