hello guys :-) ,

im a gamedeveloment student at the FH-Heidelberg and im asking for help on my research.
i currenty work on my bachelor thesis about player behavior analysis and thier responds for the AI(enemys) behaviors in first person shooters.
i want to know wich titels are the milestones in this topic and how they achiv them.
how did the AI "see" in these games?
how did the AI "handle" with that informations?
which behavior changes can be "seen" by the player?

at my research i found just one good article/paper about this topic:
http://www.cgf-ai.com/docs/straatman_remco_killzone_ai.pdf

are there any similar good papers?
i hope you guys can help because for my own its very difficult to find good sources

greets moe
ps: hope my englisch isnt that bad ;-)

I don't have any papers to offer, but maybe a bit of my rambling may be of help. Please note that I'm not 'in the know' and am going from personal gamer/hobby developer experience. First up I don't think there's a really clear evolution (yet) regarding the AI in FPS games; some people come up with great ideas for seperate games, but the field as a whole doesn't seem to be moving in any particular direction. The same is likely true for other genres, but if possible I would expand my thesis to include other genres. Particularly RPGs, which typically have more fixed rules and limits to the environment, have been studied more closely, again to my limited knowledge.

Quote:
how did the AI "see" in these games?

I don't know of any implementation where the information the AI aquires is actually implemented with computer vision (ie really looking at the game as a human would). This is technically possible (a game could render the screen an AI opponent sees for image analysis), but it would introduce a lot of overhead and might not necessarily give a better experience for the human player.

So the way I think "seeing" is typically implemented in FPS games, is that the AI is provided with a copy of the current game state; some piece of data containing player positions, waypoints, allies etc. Providing this state unfiltered to the AI would lead to 'cheating', if it enabled the AI could react to players it cannot perceive. To this end the state can be filtered to check if a player is actually in the AIs field of view, if the line of sight is not obscured, if the distance isn't to great etc. As an example, some games ignore this latter distance filtering, which aggrieves players in the form snipers who can headshot you from countless miles.

Quote:
how did the AI "handle" with that informations?

That all depends on how expressive the system for controlling the AI is. In some cases the AI might actually be limited to simple things as turning its gun towards the player and firing. With some distance information you could add grenades or have it switch to a sniper rifle. With waypoints and environmental cues you could have it scramble for cover (popularized by Gears of War, maybe they have a paper) or even have it make a detour to flank a player.

Those examples all depend on the information the AI has about the situation, which can be further enriched by having specialist scripts for specialist events. A particularly good example of this is Neverwinter Nights (an RPG unfortunately) which provides numerous events (enemy spotted, damaged, ally shouting for help etc) which can all be connected to unique scripts to create specific behaviors.

That's my ramblings for now, I hope it's of some use. An important closing point is that AI isn't nessecarily implemented to be smart, but rather to act smart. Likewise there's no point in having AI go through complex and smart routines when the player will just shoot them the instant they pop around the corner. Smart AI looks best when seen.

There is (or was) a very detailed paper on Q3's bot AI system floating around on the net. It's older technology of course, but I imagine it would be a useful reference. (Don't have a link handy at the moment, but if it's still available you should be able to find it with a little searching.)

It just occured to me that the AI Director thing in Left 4 Dead might be an interesting subject for your thesis as well. There's a bit of a hype to it, but it personifies a central AI that, rather than controling individual enemies, controls the game experience. In a nutshell it will make your life hard if you're doing well and ease up on your when you're down - ingame that is [smile]