Research And Design Of Component Modeling In 3DGIS Visualization

GIS (Geographic Inpformation System, GIS) containing the traditional science and modern technology is an edge science and a cross-disciplinary. GIS has played an important role and made significant achievements during these years. To produce more precisely and completely representatively of the real three-dimensional information, research about 3DGIS began to gradually rise, along with the proposition of Object-Oriented technology and component technology, ComGIS become a new phase of GIS. Therefore, GIS is chose as the subject of this paper.Subject described in this paper uses component technology to develop GIS platform, also it uses spatial database to restore spatial information and use topographical form to restore other information. This paper tries to implement software reusability in design and development progress of GIS software. There are four levels from top to bottom:view level, implement level, control level and the data model level. Information related with components instead of the configuration files is stored in the database. Add the components in the system design components must be designed model structure. Interface model in accordance with the provisions of the terrain generation module to add lighting effects module.This paper analyzed of spatial data types and their structure, designed a preliminary spatial database of GIS according to the type of spatial data, geographic data is the main operating target which includes description of the relationship among spatial entities, spatial location and description of geographical entities. Designed commonly used vector data, attribute data and other storage structures, and the design of database tables reserved position to facilitate user of the system to extend the data types when components are changed.Analysis and experiments show that the component model of 3DGIS designed by this paper which uses the database to storage component adding information instead of system configuration files, can be used in model addition which is designed by components structure. The experiment of model addition which is processed using the method designed in this paper shows it as a strong supporting role and its significance.