Dynamic Management of Geographic Data in a Virtual Environment
In order to achieve true 3D user interaction with geographic information, an interface between a virtual environment system and a geographic information system has been designed and implemented. This VE/GIS interface is based on a loose coupling of the underlying geographic database and the virtual environment system via a dynamic data-translator. This process monitors events initiated by the user in the virtual environment. Based on these events, appropriate queries are generated and sent to the geographic database. On the other hand, the data-translator receives GIS data as a result of queries, and converts these data into appropriate representations for the virtual environment. Moreover, the VE/GIS interface performs data-management tasks in order to efficiently utilize the limited amount of data that can be kept on-line in the virtual environment. To this aim, an object caching mechanism has been devised. The dynamic data-translator supports both explicit and implicit access to the geographic database. These concepts are illustrated in a virtual environment based user interface that provides basic interaction facilities for the intuitive exploration of geographic information. The approach chosen leads to a layered data management scheme where issues related to collaborative VE experiences, such as guaranteed performance, synchronization, concurrent access, and network traffic limitations, can be handled at an appropriate system level.
KeywordsGeographic Information System Geographic Information System Virtual Environment Geographic Data Geographic Database
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- 1.Tom Vijlbrief and Peter van Oosterom, The GEO++ System: An Extensible GIS. Proc. 5th Int. Symp. on Spatial Data Handling, pp. 40–50, Aug. 1992.Google Scholar
- 3.P. van Oosterom, W. Vertegaal, M. van Hekken, and T. Vijlbrief, Integrated 3D Modelling within a GIS. Proc. Advanced Geographic Data Modelling workshop, Delft (NL), 12–14 Sep. 1994.Google Scholar
- 4.T. Gaskins, PEXlib Programming Manual. O’Reilly & Associates, Inc., Dec. 1992.Google Scholar
- 5.H. Rheingold, Virtual Reality, Summit Books, New York, 1991.Google Scholar
- 6.G. Burdea and P. Coiffet, Virtual Reality Technology, Wiley, new York, 1994.Google Scholar
- 7.K. M. Fairchild, Information Management Using Virtual Reality-Based Visualisations. In: A. Wexelblat (ed.), Virtual Reality — Applications and Explorations. Academic Press, Cambridge, MA, 1993.Google Scholar
- 8.M. W. McGreevy, Virtual Reality and Planetary Exploration. In: A. Wexelblat (ed.), Virtual Reality — Applications and Explorations. Academic Press, Cambridge, MA, 1993.Google Scholar
- 9.M. Stonebraker, Sequoia 2000: A Reflection on the First Three Years. IEEE Computational Science and Engineering, pp. 63–72, Winter 1994.Google Scholar
- 10.F. Bagiana and G. J. Jense, Virtual Environment Techniques for the Exploration of Earth Observation Data, Proc. 2nd EUROGRAPHICS Workshop on Virtual Environments, Monte Carlo (Monaco), Feb. 1995.Google Scholar
- 11.dVS Technical Overview. Division Ltd., Bristol, UK, 1993.Google Scholar
- 12.L. H. van der Schee and G. J. Jense, Interacting with Geographic Information in a Virtual Environment. Proc. Joint European Conference on Geographic Information, The Hague (NL), March 1995.Google Scholar
- 13.DIS Steering Committee, The DIS Vision, Technical Report IST-SP-94-01, Institute for Simulation and Training, May 1994.Google Scholar