Smart objects is a way to take some of the functions related to the agent and put into objects in the environment. Markers in the level can be tagged with information such if the position is a good cover. That way the agent can search for the closest cover marker instead. Another way of looking at it is as if the markers tell the AI about the utility for any number of activity's. Markers on the side of the file cabinet are good for cover and the one in front is good for idle activity. When waiting for the player to show up the agent can sort the evil plans in the file cabinet and when the player arrive to shut down the operations of Evil Inc he can jump into cover. The idle marker can have the details on what animations to play, what voices to say and how long to perform it.
Select what agents can use this object. Only cleaners are allowed to water the plants and guards are the only ones allowed to use the weapon locker. More then one dimension of this can be added and one useful one is to tag by area. A guard that founds the player acting strange and follow him across the street should not pick up a guard position at the wrong building. He should only look for GuardIdle objects in the area he is responsible for.
Who owns the object and has the right to use it. If a police officer goes to the water fountain he would not be happy if another agent have stolen his table when he gets back. This ownership often need to include a set of objects. He can own the chair, the phone on the table and the file cabinet.
Smart objects can be chained be setting suggestions for objects to be used after the current one. For example a BathRoomIdle suggest a WashHandsIdle.
Some objects are better then other. When the guard is thinking about taking cover behind the metal filing cabinet and the weak wooden table he should pick the more solid one. Each objects can be given a priority.
The current state of the object can be retrieved and that way agents can remember changes to it. A guard can notice a open door or a light left on.
- GameAi Wiki - The Sims
- Constraining Autonomous Character Behavior with Human Concepts, AIGPW2 p189-197. - 2004.