Implementation Of Virtual Scene And Weather Phenomena Simulation In 3D GIS

Three-dimensional Geographic Information System (3D GIS) is one of the most important branches in the field of GIS. 3D GIS is always the hotspot of studies and applications since 1980s.The study fields include Database, GIS, COMPUTER GRAPHICS, and VR etc. The rapid development of 3D GIS shows the direction of GIS in the future. Weather Forecast in 3D Scene is one brand new subject of 3D GIS. Its final object is to become one 3D GIS platform for Weather Forecast Application.This paper is base on the actual development of "Virtual Scene and Weather System (SeiVWP)" by the author. We concentrate our mind on some critical techniques of implementation such as the algorithms of transferring large terrain data, multi-resolution texture mapping and 3D simulation and rendering of weather phenomenon. However the third part is the core of the entire paper and the 3D cloud simulation is based on the static cloud real-time rendering.At present, the techniques of simulating weather phenomena is mainly physically-based, then appropriately simplify mathematics models. If directly applying these techniques on 3D GIS, with the condition of the current hardware performance, the requirement of the application is impossible to be satisfied. So, the simulation in this paper is directed by actual application, to make sure realistic-looking animation and real-time rendering effects.The objective of SeiVWP is to build a weather system based on 3D virtual scene and give support to weather simulation and analyze. SeiVWP has been used by Shen Yang military hydrology department. In conclusion, based on the reference to and the combination with recent research fruits, this paper implemented some methods such as the algorithms of transferring large terrain data, multi-resolution texture mapping and 3D simulation and rendering of weather phenomenon.. These methods that the author proposes in this paper have been successfully embedded in the "Virtual Scene and Weather System" which is implemented by SEI. These methods have been tested and the result is satisfying.