Everybody complains about artificial intelligence. It's too dumb. It's too all-knowing. What it really is is too opaque. AI design remains one of the most mysterious disciplines of video game creation. Well, if you've ever wondered about how the rules governing the allies and opponents in a video game, then a blog post regarding Sir, You Are Being Hunted got some answers for you.
Designer Tom Betts is part of the team working on the upcoming PC shooter from Big Robot, which has aristocratic British machinemen that make sport of chasing down and slaughtering human beings. Betts has posted an entry on the game's site about the various AI states players wll encounter in the game:
Wander: NPCs move between hub locations based on various internal reasoning algorithmns, sometimes they will stop for a while and rest, or even loiter on roads outside of the settlements.
Alert/Search: If an NPC hears a nearby sound, or sees either the player or another NPC from a rival faction, they will switch into this state. In this state the hunter approaches locations close to the last heard sound or last sighting, their viewcone detection increases and they will continue exploring nearby areas until they encounter an enemy or eventually get bored and return to wandering.
Combat: If a hunter sees a target and can approach to within combat range (dependent on the range of their weapon etc), they will do so. In this state NPCs will reload and move to keep in range of their target and when losing sight of the target they will attempt to round appropriate corners to track them down.
Cover: Every time an NPC is injured they have a chance of switching to a cover-seeking state (more likely as they become more heavily wounded). When in this state they abandon all combat and run to the nearest cover location (essentially calculated from a list of locations that are out of sight of the enemy that is pursuing them). Once in cover they will constantly look around themselves to spot any chasing enemy. If found and attacked they will run on to another potential safe spot. If safe for long enough they will regain their courage and return to either a combat or search state.
The post also talks about the enemy robot factions that you'll come into contact with. Details like this make me hopeful that Sir, You Are Being Hunted will have more than an awesome title and clever concept going for it.
Building Hunted's AI: Some Fundamental Elements