The State of AI In Games

CowboyRobot writes "Carnegie Mellon researcher Alexander Nareyek has an article at ACM Queue describing how the role of graphics as the leading technology in gaming is being replaced by advancements in artificial intelligence. The author targets some game AI: 'Early milestone demonstrations for the publisher, press presentations, and other hype-generating events do not promote inclusion of a globally/consistently good AI, but instead focus on one or two 'absolutely unexpected but genius outcomes of revolutionary new and complex AI procedures' (did you spot the ironic tone?) that provide the necessary 'wows'.' He concludes by suggesting: 'we need to see more effort to make AI functionality available for the designers/artists.'"

Comments

A.I.

[Deliveranc3]

The biggest advance in artificial intelligence so far came when the reaper bot started saying things like.

"I destroy you"
"Cry to your mom. b!cyh"

etc. I mean that was most humanlike characteristic ever to be properly emulated.

Playing experience

[Vexware]

Having read the article, I think that the author seems to forget that though we know have pretty much reached the summit of the quality of graphics, AI is not the only direction that future games will have to be aiming for; I believe physics engines are taking a pogressingly important role in video games, and this is an area which I think developers will concentrate on, as it is showing more and more importance for gamers.

The problem is that now, AI is as "basic" as physics engines are. If you look at the best selling games, they probably have bad AI (XIII comes to mind, that game's AI is hideous) -- and an average physics engine. If you ask me, developers will have to find the balance between developing both, because these elements are becoming big enjoyment factors in player experience, as the players realise that good AI makes for a more realistic experience, and allows the player to progress in several ways instead of having to follow the same, linear route (a feeling which decreases replayability a lot). As for the physics engines, it's just something else which more and more players see as important; just imagine the possibility of great puzzles with a great physics engine.

A game with both great AI and a realistic physics engine ([cough]Half-Life 2[/cough]) just needs some good level design for these to come through, and that is how you will create the ultimate player experience.

The author of the article says the AI is more than just how the NPCs react, but nowadays I think the emphasis has to be put on this type of AI anyway, as it is still kind of apalling in most games. If a game has good AI, it can allow more freedom of choice to the player as the NPCs will know how to react accordingly to the player's actions and decisions. If NPCs are ready to act in "real time" to any situation, it is less a case of the player having to adapt to a game, following a linear route and ending up against a horde of enemies and some prescripted event, but more a case of the game "adapting" to what the player chooses to do, hence giving the player greater freedom and a better experience.

As for the evolution of physics engines, one has to see how important this is becoming; there are so much more progression possibilities for a game with a good physics engine. This allows the player to interact with his/her environment in a much richer way, and use it much more as he/she would like to have it exploited. Coupled with a good AI, this can make for an amazingly realistic game and a much better playing experience, and in my opinion, these are the departments which developers have to aim expanding on.

Re:Playing experience

[Shadeborn]

most of the events which gave the original its 'wow' were scripted events.

True, but Half-Life does also have team-based AI for some monsters (most notably the marines, the black ops and and the alien dogs). For example, the level designer could designate one of the monsters as a leader and the others would follow its lead. If the player killed the leader first, the rest would disperse and stop fighting as effectively.

Also, the monsters could use the terrain for their advantage, if the level designer put "hint" entities at corners, doorways, bunkers, around obstacles and such. For example, the marines do take cover behind obstacles and try to draw the player into a crossfire.

The most "intelligent" monsters of Half-Life are the female black ops with stealth gear. They did require a lot of hint entities to fight effectively, but could lure the player into an ambush by using one of them as bait while the others circled around the player.

Re:Where's the advancement?

[flabbergast]

Did the parent read the article? I don't understand why you'd be puzzled. The author specifically states that game AI is different from research AI and almost all games use the same FSM and decision trees. Only games such as Creatures or Black and White use "advanced" research AI techniques like genetic algorithms or neural networks. FSMs and decisions tree operate at a basic level:

If in this state with these conditions move to state Q

otherwise move to state R

So, half-life and deux-ex II both use the same basic FSMs and decision trees, and "advancement" doesn't come simply from increasing CPU power or more RAM (those things obviously help though) but also the programmers/designers ability to conceive of possible scenarios that could occur. So, if you want an enemy to flank you and kill you then someone has to think ahead of time "Well gee, what state would this bot need to be in before he would go ahead and try to find a way to get behind the player to flank him?" Then, the programmer has to find a way to get the bot to flank you (i.e. find a path to get behind you without you seeing) and then kill you. That's not exactly a trivial task, especially with so many possible scenarios involved.

Speaking of game AI...

[WWWWolf]

Memetic AI for Neverwinter Nights. This stuff is pretty innovative, at least in theory, and I hope they eventually get to the 1.0 phase with more than just the groundwork done. The approach it takes might be an interesting, even intuitive, way for building the NPC/creature behavior from ground up.