建立WebGIS的月球三维可视化关键技术

Key Technologies of a WebGIS-Based 3D Visualization System for the Moon

嫦娥工程获得了大量月球探测数据。针对让公众用户通过网络获取月球信息,更好了解月球知识的需求,地面应用系统提出了建立基于WebGIS的月球三维可视化系统的解决方案。首先介绍了国内外三维月球的发展现状,详细分析了开发WebGIS系统的客户端和服务器端技术,重点阐述了月球空间数据模型和三维场景可视化渲染等三维GIS可视化关键技术,为建立我国的三维月球可视化系统提供了理论支持。

Data of the moon in a large amount have been recorded in the Chang＇E lunar exploration project. To meet the public need of better understanding the moon through the Web, the Ground Application System proposed solutions of 3-dimensional visualization systems for the moon based on the WebGIS. In this paper we first introduce the status of the development of visualization systems for the moon in China and abroad. We then analyze technologies and platform software components of developing clients and servers in the WebGIS. We choose the Javascript as the technology to develop a client, and choose the Weblogic as a platform to develop a server. We also use the ArcGIS Server and the MGIS GIS software of domestic origin as the development platforms in a design of a 3-dimensional visualization system for the moon. The paper focuses on key technologies of 3-dimensional GIS visualization, such as techniques of modeling 3-dimensional lunar data and algorithms of organizing/scheduling/rendering 3-dimensional scene graphs. A system according to our design organizes DEM and DOM lunar data with the pyramid data structure, and manages vector data （e.g. terrain names ） hierarchically. It assigns two queues to accept user requests and send processed data, respectively. This ensures fluent and fast display of 3-dimensional scenes at a front end. The paper finally summarizes relevant technologies and outlines of the solution to support building 3-dimensional moon-visualization systems in China.