GIS-based Visualization Module Development

With the development of computer technology, the requirement for various data processing is increasing, especially spatial data. The development of digital technology and the acquirement of spatial information allow us to obtain data with larger volumes, higher dimension and complexity. Therefore, the analysis and visualization of these data are more challenge. Large-scale and multi-dimensional visualization is crucial when analyzing implicit features in the data. There are many types of spatial data, such as regional statistics data, geographic information data and electromagnetic situational data. Based on the distribution of geographic information and the integration of data from multiple sources, using GIS to present this information is a new method to explore multi-dimensional space-time data. In this thesis, we focus on the visualization and component development of these two types of spatial date based on the geographic information system.Firstly, the statistics data visualization module based on B/S is developed. The raw data is complex and has multiple attributes. It can be divided into spatial data and statistical data. Spatial data describes the geometric property of spatial objects and statistical data describes the statistics information in the same space. The data from multiple sources is first unified and integrated for modeling, analysis, and visualization, such as triangulation, geometric grid generation. Different applications can have different map projection and coordinate system. The property is associated with the geometrical primitives, and can be displayed in a GIS platform. The GIS platform provides rotation, translation, scaling and search operations. Finally, the GIS platform is embedded in a Web browser. Users can use GIS services tO. visualize data directly from the browser, and change the configuration and its associated parameters to generate personalized thematic maps, such as color and glyph.Secondly, we develop a visualization system of multi-dimensional geographic information data to explore the feature and relationship in multi-dimensional data. We use a variety of methods like data management and cleaning, interactive visualization and layout technique to achieve a better visualization result.Last part of this thesis is a C/S based electromagnetic situation visualization system. This system is implemented based on three-tier C/S structure. Firstly, we generate 3D electromagnetic situational models and 3D models of each equipment according to different electromagnetic properties. Secondly, based on the requirement, the user construct entities, including 3D electromagnetic situational models and 3D models of equipment. Then the user deploys each model of entity on a 3D earth, and specifies different operations for each equipment according to the simulation requirement. Finally, the user runs the simulation. This system can express electromagnetic situation more accurately and clearer with 3D visualization. Furthermore, this system can help the commander to deploy force and give commands. It is promising to play an important role in the future electronic battlefield.