Interações de NPCs mais humanas em jogos digitais: desenvolvimento de um NPC emocionalmente responsivo com inteligência artificial e animação 3D

Abstract

This final project explores the development of an emotionally responsive non-playable character (NPC) prototype, aiming to demonstrate how this approach can enrich narrative and interaction in digital games. The research stems from the problem that NPCs traditionally exhibit rigid behaviors and pre-programmed dialogue, which requires player customization. The main goal is to create an interactive experience in which the NPC reacts verbally and expressively based on the player's speech, bringing human-computer interaction closer to human communication. The methodology adopted for developing the prototype involves the integration of advanced technologies. The ConvAI platform was used for natural language processing, including speech recognition, response generation through a language model (LLM), and emotion detection. The character was modeled with MetaHuman Creator and implemented in Unreal Engine 5, where a system of emotional states was created to trigger physical and bodily animations corresponding to the emotions locked by the AI. The prototype was set within the context of the "Ghost Architecture" project, which digitally reconstructs the historic Plácido Castle in Fortaleza, with the NPC acting as a mediator between the player and the local memory. As a result, a functional prototype was built in which the player can freely converse with the NPC, who responds dynamically and consistently both verbally and through nonverbal expressions. The integration between ConvAI's AI and custom animations in Unreal Engine enabled the creation of multimodal reactions, where the emotion expressed in the player's speech triggers synchronized visual and behavioral responses in the character. A parallel application of the concepts was performed in a virtual reality game, reinforcing the methodology's predictions in different narrative contexts. The work concludes that the cohesive integration of generative artificial intelligence, emotional modeling, and 3D animation is a viable and effective approach to overcoming the limitations of traditional NPCs. The prototype demonstrates that characters capable of understanding and expressing emotions enrich the game experience, increase uniqueness, and deepen the narrative connection. The research points to a future where NPCs can act as more innovative and innovative interlocutors, transforming the nature of interaction in digital games