how could you really incorporate emotions in a game, for example an FPS game? It would be kind of cool to have enemy soldiers showing fear, anger, etc YOu could have a soldier trembling, dropping his gun, etc due to fear. You could also have people pleading for their lives a la Rise of the Triads. COuld a concept like this really be implemented in a FPS game?

yeah it would rock and it could certainly be implemented. in a lot of games you already have NPCs reacting to how wounded they are and whether or not they have allies nearby. when wounded + not any allies around, they run away. with some more appropriate animation you could make that look like fear.

you could add a basic emotional system for the player to you AI engine. it wouldn''t be too hard to add some basic behaviors similar to the above.

-me

For the most part, emotions should be used as coefficients in equations that determine action. For example, the "scared" coefficient - as it increases - would increase the likelyhood of the soldier running away or surrendering. This was treated rather well in the Close Combat games. There are also some decent artilces floating around in the Articles & Resources section on here.

Dave Mark
President and Lead Designer
Intrinsic Algorithm Development
"Reducing the world to mathematical equations!"

Pretty much the most work you would have to put into something like this would be outlining the various emotions the AI can have, and how certain things effect those emotions.

Dave has the right idea, and it can get even better. I think (cause I''ve never done it myself) emergent behaviour would be a given side-effect of this, especially if you make the AI agents react to other AI agent''s emotions. So lets say that 5 AI guys carrying handguns round the corner and come face-to-face with you carrying a machine gun. 3 of the 5 turn and seek cover but two stay and start shooting at you. If agents in proxomity to other agents can be affected by their emotions, and the 3 guys running get emotional boosts from their buddie standing fast, some of them may turn back to fight (if that knocks them below their given stress level).

There''s planty of ways to play with AI emotions and how they affect the gameplay, you just have to decide how complex you''re willing to make the interactions.

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Right on, Drew. Basically you can treat it as another state machine (I would suggest a fuzzy one) running in parallel to the ACTION state machine.

I like the idea of the emergent behavior. My initial thought was that the 2 remaining dudes may tend to flee because they are now more outnumbered. Of course, it would be interesting if the 3 were coming back to fight while the other 2 were turning to leave. I feel some confusion could result until they worked it out!

Dave Mark
President and Lead Designer
Intrinsic Algorithm Development
"Reducing the world to mathematical equations!"

they might even panic and fumble around with their weapons resulting in the death of their teammates. You might also have someone panic when he sees his teammates fall.

The Creatures series of games is an excellent example of the development and use of emotions within a game context. Emotions varied depending on stimulus and definitely affected behaviour. Obviously though, the Creatures AI architecture was quite complex: a large niched neural network. It''s not the sort of thing you necessarily want to put in a FPS where the life expectancy of an NPC (or player) is in seconds, rather than months or years!

In FPS and similar genre games you would be better served by a simpler approach; perhaps something along the lines of what IF and Gaiiden suggest. You might want to consider the Belief, Desire, Intention approach (BDI) to planning, since Desires and Intentions are definitely driven by emotions.

Cheers,

Timkin