Canyons, deltas and plains: towards a unified sculptural model of location-based hypertext

With the growing ubiquity of mobile devices, new ways of sensing context and the emergence of the mobile Web, digital storytelling is escaping the confines of the desktop and intertwinging in new and interesting ways with the physical world. Mobile, location aware, narrative systems are being applied to a range of areas including tour guides, educational tools and interactive fiction. Despite this there is little understanding of how these applications are related or how they link with existing hypertext models and theory. We argue that location aware narrative systems tend to follow three patterns (canyons, deltas and plains) and that it is possible to represent all of these patterns in a conceptual sculptural hypertext model. Our model builds on a general sculptural mechansim (of pre-conditions and behaviours) to include locality and narrative transitions as first class elements, opening the possibility of standardised viewers, formats, and hybrid stories. We show how existing structures can be mapped onto this conceptual sculptural model, and how narratives defined in the model can take advantage of open data sources and sensed contextual data. To demonstrate this we present the GeoYarn system, a prototype which implements the model to create interactive, location aware narratives, using all three patterns.