Modeling and Visualizing 3d Urban Environment via Internet for Urban Planning and Monitoring

Geographical Information System (GIS) technology has been an important tool in supporting urban planning and management for efficient accessibility to more, better, and timely information. This paper presents our research results of visualizing 3D city model in a web explorer environment under the supports of digital building model (DBM), digital terrain model (DTM), large-scale true urban orthoimage, and actual building sidewall pictures. A system has initially been designed and developed under a client/server architecture, which integrates Internet GIS with multi-tier web application for creation of a 3D city model. The front-end client provides a user interface for setting properties of the 3D model, while the backend server processes the parameters and generates the 3D model, which is then sent back to the VRML-enabled WWW browser for display and navigation. The technology for display and navigation of the 3D model is actually a Java JSP/Servlet technology built under multi-tier web architecture. The data accessing and processing of the technology is through Java programming language to link the displayer with the database where the required GIS spatial data are stored. The results from our experiment demonstrated that this developed architecture is able to display and visualize 3D city data in web environment for public access. Using the sidewall pictures taken from real city buildings, we refill the white walls of urban buildings into a real appearance as seen in our real world city. The player provides several click buttons to change the effect and position of visualization, including rotation, zoom, pan, seek etc. The users can easily to view details of specific building, the entire city in a moving 3 dimensions, to locate a specific building, and so on.