Menz, StefanDammertz, HolgerHanika, JohannesWeber, MichaelLensch, Hendrik P. A.Reinhard Koch and Andreas Kolb and Christof Rezk-Salama2014-02-012014-02-012010978-3-905673-79-1https://doi.org/10.2312/PE/VMV/VMV10/017-024Procedural modeling allows to create highly complex 3D scenes from a small set of construction rules, which has several advantages over storing the full data of an object. The most important ones are a very small memory footprint and the ability to generate infinite variations of one prototype object by using the same set of rules. However, the problem that procedural modeling imposes on the user is to define a reasonable set of rules to generate a specific object. To simplify this task, we present new interaction metaphors for a graphical user interface and a minimal set of geometric operations that allow the user to efficiently create such rules and the respective models. These metaphors are then implemented in a prototype system and are evaluated by user tests with regard to usability and user performance. The results show that the system enables even inexperienced users to create complex 3D objects via procedural modeling using the presented approach.Categories and Subject Descriptors (according to ACM CCS): H.5.2 [User Interfaces]: Graphical User Interface (GUI), Interaction Styles, Evaluation I.6.3-5 [Simulation and Modeling]: Applications; Model Validation and Analysis; Model Development J.5 [Arts and Humanities]: Architecture