Studying Accessible States of User Interfaces on Tabletops

Interactive tabletops are the promising platforms to host Geographic Information System (GIS). Currently, user interfaces on tabletops do not suit GIS well enough for complex interaction. Thus it limits efficiency and collaboration. This paper analyses the design requirements from the perspective of the operational semantics, which refer to users´ intention deduced from their operation sequence. We investigate common operations and summarize four accessible states of user interfaces. Then we put forward a user interface management model. Based on this model we design a new set of user interfaces targeted for GIS on tabletops to improve the usability, especially the collaboration.