International Journal of Computational Geometry & Applications C World Scientiic Publishing Company Virtual Geoexploration: Concepts and Design Choices
نویسندگان
چکیده
A trip through a virtual world is a powerful metaphor and a natural way of interacting with a geographic information system (GIS). Virtual reality (VR) systems provide visual realism and real-time navigation and interaction for data in core, but fail to cope with very large amounts of data, and to provide the general functionality of information systems. We describe a prototype system that overcomes these problems by coupling two platforms: A client that runs the VR component interacts via a (local or wide area) network with a server that runs an object oriented database containing geographic data. For the purpose of accessing data eeciently, we describe how to integrate a geometric index into the database, and how to perform the operations that are requested in a real-time trip through the virtual world.
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