Design Foundations for Emotional Game Characters

"Design Foundations for Emotional Game Characters" argues that non-player characters in games lack emotional depth, and that automated emotion systems can enhance player engagement while easing the authorial burden on designers. Its central aim is a portable, testable blueprint for a family of emotion engines. The authors ground this blueprint in psychoevolutionary synthesis and cognitive appraisal theory, reviewing existing cognitive architectures such as LIDA, SOAR, ACT-R, and CLARION, and then testing their proposals against scenarios drawn from animated films, particularly Disney and Pixar productions.

The paper's core contribution is an architecture that combines Plutchik's eight primary emotions with Scherer-style appraisal dimensions. Events are mapped to emotions through primary appraisals of relevance and congruence and secondary appraisals of accountability, coping, and future expectancy. Each emotion is assigned a distinctive pattern of appraisal dimensions, and the model specifies emotion decay, expression thresholds, and separate outputs for behavior, animation, and audio. The authors argue that this pairing is preferable to the widely used OCC model, which dominates game implementations often without documented justification, because it links affect dimensions directly to emotion types while remaining computationally feasible.

Scope is primarily theoretical and illustrative rather than empirical. Analyses of characters such as Jasmine, Elsa, and Mulan, along with examples from The Incredibles 2, serve as worked demonstrations of how joy, grief, anger, surprise, and vigilance can be encoded and validated. The authors explicitly acknowledge that the nature of emotion remains theoretically unresolved, that their choice of Plutchik's prototypes is an interpretive commitment, and that designers should state their chosen emotion framework openly. Their proposed database of appraised scenarios is presented as a foundation for future validation rather than a completed body of evidence.