A VRML Terrain Visualization Approach

Geographic Information Systems (GIS) are used to store, manipulate and analyze spatially referenced data. In the past, GIS were 2D, map-based systems using non-interactive high-resolution display. Advanced graphical libraries such as VRML (Virtual Reality Modeling Language) make possible to effectively model and thereafter render the third dimension on WWW. Landscape visualization in a GIS involves visualizing and manipulating large-scale terrains, which are typically massive. The time required in rendering such a model would prohibit any real-time interaction using the current generation of VRML browsers. This paper discusses this specific problem and proposes VRML techniques on how to reduce the rendering time needed for large terrain visualization. It also presents a case study where the proposed approach is used to implement a 3D visualization of Attica, Greece.