On the convergence of 3D-GIS, CAD and 3D Simulation

Urban information space Due to improved tools for the design and acquisition of 3D models, to the wider acceptance of 3D technology, and 3D spatial databases the creation and management of urban information spaces representing entire cities in the virtual world is feasible nowadays. The urban information space is not limited to 3D building geometry but includes building semantics as well providing necessary information for urban planning, construction and management. However, sharing information between professionals from various disciplines and non-professional users such as citizens affected by planning proposals is a big challenge for the future. Currently, traditional disciplines such as architecture, civil engineering and GIS create classic information islands with different focus. Usually GIS is used to represent the current status of a whole city for administrative purposes. In contrast, planning and construction professionals focus on the future shape and status of a relatively small part city or just individual buildings in very high detail. In general, three categories of urban geo-information can be distinguished: • GIS: two-dimensional maps, digital terrain model, 3D buildings with simple geometr