A Formalism and a Tool for Diverging Requirements in VR Scenario Modeling

Any VR scenario should offer a certain degree of nonlinearity or openness regarding the story progress as a consequence of the interaction with the user. In this paper we propose a new formalism, which we regard as suitable for authors and artists to develop compelling and flexible interactive stories. We distinguish two levels of openness in storytelling. The first level of openness deals with the freedom of the author. Storytelling is regarded as an ill-defined problem and hence Authoring Tools have to support the author defining his goal and to iteratively describe, develop and improve his idea of the story. The second level of openness deals with the freedom of the user. From the perspective of the audience of an interactive story we want the plot to behave in personalized ways, i.e. depending on the actions of the user the story should develop in different directions. In accordance with these two types of openness we developed a prototypical graph based tool for the creation of non-linear scripts to make VR scenario authoring accessible for a much greater number of creative people.