I.M.T. Swartjes

Purposeful Authoring for Emergent Narrative

Emergent narrative (EN) is a narrative concept in virtual reality that relies on emergence for a flexible shaping of stories as opposed to fixed pre-determined plots. This has consequences for the creative role of the author in an EN system. In this paper, we aim to clarify the actual function of the author by investigating what is exactly mediated in ENs and how this can be filled in by an author at design time.

Let's Pretend I Had a Sword

We describe how autonomous character agents that inhabit a story world can make (out-of-character) decisions about its details, filling in the story world as they go. We describe how we model these kind of late commitment decisions, and discuss how we use them to support action selection and to justify the adoption of character goals. Although a rigorous evaluation remains future work, we have implemented the approach presented here and have performed some exploratory testing.

A Tabletop Board Game Interface for Multi-User Interaction with a Storytelling System

The Interactive Storyteller is an interactive storytelling system with a multi-user tabletop interface. Our goal was to design a generic framework combining emergent narrative, where stories emerge from the actions of autonomous intelligent agents, with the social aspects of traditional board games. As a visual representation of the story world, a map is displayed on a multi-touch table. Users can interact with the story by touching an interface on the table surface with their fingers and by moving tangible objects that represent the characters. This type of interface, where multiple users are gathered around a table with equal access to the characters and the story world, offers a more social setting for interaction than most existing interfaces for AI-based interactive storytelling.

An Experiment in Improvised Interactive Drama

To inform the design of interactive drama systems, we investigate the experience of an interactor being part of a story that they can have a fundamental influence on. Improvisational theatre might serve as a model for this experience, where there is no pre-scripted plot; each of its actors shares responsibility for the collaborative emergence of a story. This requires a performer attitude from the interactor. We describe an experiment in which improv actors create a story together with subjects who have no improv experience, to find out how we can characterize this experience, and how it might be achieved. Our results support a recent hypothesis that an interactor in interactive drama might be treated as a collaborative performer rather than an (antagonistic) player.

A tabletop interactive storytelling system: designing for social interaction

This paper presents the Interactive Storyteller, a multi-user interface for AI-based interactive storytelling, where stories emerge from the interaction of human players with intelligent characters in a simulated story world. To support face-to-face contact and social interaction, we position users around a shared multi-touch table, which very much resembles the social setting of traditional tabletop board games. To our knowledge, the Interactive Storyteller is the first AI-based interactive storytelling system that combines an emergent narrative approach with the social aspects of traditional tabletop board games. We carried out user experiments to investigate to what extent our system supports social interaction. By analysing the interactions of pairs of children with the Interactive Storyteller, we determined which system aspects triggered cooperation and highly social behaviour and which aspects caused players to behave less socially. We also tried to find out whether the use of tangible playing pieces offered any advantages over touch-only interaction, but we did not find any differences between the two.

Having one's cake and eating it too: coherence of children's emergent narratives

In the emergent narrative approach to Interactive Storytelling, narratives arise from the interactions between player- or computer-controlled characters in a simulated story world. This approach offers much freedom to the players, but this freedom may come at the cost of narrative structure. In this paper we study stories created by children using a storytelling system based on the emergent narrative approach. We investigate how coherent these stories actually are and which types of character actions contribute the most to story coherence, defined in terms of the causal connectedness of story elements. We find that although the children do produce goal-directed story lines, overall the stories are only partially coherent. This can be explained by the improvisational nature of the children’s storytelling with our system, where the interactive experience of the players is more important than the production of a coherent narrative. We also observe that the communication between the children, external to the system, plays an important role in establishing coherence of the created stories.