A 3D Metaphor for Authoring Realtime Interactive Systems Supporting Different Author Roles

Creating a user interface for a realtime interactive system is often a more challenging task than creating a traditional graphical user interface. A strategy to cope with the additional complexity is a division of work involving several authors with different expertise. Supporting these authors with a single tool can foster collaboration and solve problems due to incompatibilities and the need for data exchange between traditional tools. For such a unified tool, this paper introduces a 3D metaphor for organizing authoring steps and for visualizing the interfaces between different author roles. It utilizes a specifically shaped 3D space where layers are arranged in parallel. A layer represents the workspace of a specific author role. The authors place entities (e.g. widgets or graphical representation of gestures) on the layers and may combine them to form more complex entities. The 3D metaphor offers affordances for possible interactions to the author. In addition, it suggests visualizations. Authors can use a slider to move the layers back and forth. Transparency is used to blend from one layer to the next. In addition, authors can change to a pre-set camera position that allows for a birds-eye view of the layers. In the space between the layers, dependencies are visualized. For each switch, a transition animation is used. Moreover, this paper presents an authoring tool based on this 3D metaphor. The tool has been used in a user test where several experts built a realtime interactive system with this tool. The evaluation shows that the 3D metaphor is easy to grasp and supports the authors in their tasks.