An alternative for a 3D GIS

Siyka Zlatanova ITC, 7500 AA P.O. Box 6, Enschede, the Netherlands [email protected] Summary An increasing need for a 3D GIS is observed in many areas in the last several years that challenges researchers and vendors to find a solution for maintenance and analysis of 3D data. Advances in the field of software and hardware development warranty the "luxury" to operate with the third dimension. Based on some recent software achievements, the paper presents a client-server approach for a 3D GIS. The approach permits query and analysis of spatial and semantic information by remote users across the Web. The data are hosted in a DBMS according to a specially designed conceptual schema, which allows storage of geometry, attributes, spatial relationships and behaviour of object. The approach is based on established Web mechanisms to control the access to the database and create documents on the fly. The new aspect is the elaborated employment of VRML for visualisation, query and exploration of 3D data. A GUI on the client site provides the users with means (fill-out forms) to specify SQL queries and visualise 3D outcomes in virtual reality environment. A prototype system and a number of examples validate the proposed concepts.