GAMYGDALA: An Emotion Engine for Games

In this paper we present GAMYGDALA, an emotional appraisal engine that enables game developers to easily add emotions to their Non-Player Characters (NPC). Our approach proposes a solution that is positioned between event coding of affect, where individual events have predetermined annotated emotional consequences for NPCs, and a full blown cognitive appraisal model. Instead, for an NPC that needs emotions the game developer defines goals and annotates game events with a relation to these goals. Based on this input, GAMYGDALA produces an emotion for that NPC according to the well-known OCC model. In this paper we provide evidence for the following: GAMYGDALA provides black-box Game-AI independent emotion support, is efficient for large numbers of NPCs, and is psychologically grounded.

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