Graphics, Imaging, and Games Lab

Crafting satisfying narratives while preserving player freedom of action is a longstanding challenge for computer games.  Many games use a quest structure, allowing players to experience content nonlinearly.  However, this risks creating disjointed stories when side quests only minimally integrate with the main story. We propose a flexible, scene-based story system that reacts dynamically to the player’s actions.

In the proposed system, stories are defined within a graph where nodes represent scenes and edges represent causality.  Nodes are tagged with information including possible locations for the scene, the plans or goals connected to the scene, and the agents and objects involved in the scene.  At any time, the distance from the player’s current game state to nodes in the story graph is measured according to five dimensions of nonlinearity: time, space, causality, agents involved, and the player’s goal.  The system will use the distance to determine what nodes should be available at any given time.  Scenes will be modified dynamically according to when and where they ultimately take place, ensuring that each node has a narrative connection to its predecessors.  This system allows for potentially connected stories driven by player action, leading to a more cohesive emergent story.