Sunlight Analysis Based On CyberCity GIS

With the rapid development of building and modifying cities in the nation, the increase of building height and the reduce of buildings' distance leads to the shortage of sunlight on resident building, which enhance the conflict between the land using rate and the quality of sunlight condition. So, insuring buildings' position, interval and the effect of the buildings' shapes and shadows, saving land and ensuring sunlight environment equality, and creating a pleasing condition for the citizen is an essential element in the city planning and design now.Aiming at the lack of traditional sunlight analysis system based on CAD system for processing urban planning and management this paper presents an idea that based on CyberCity GIS and other techniques, all kinds of urban planning information are organized and managed on unite database platform and many application subjects of urban planning are integrated. Some relative key techniques including the design of 3D data model, database management based on Oracle, the fusion between CAD data and GIS data, sunlight analysis and so on are emphasized.The paper introduces the realization and the characteristics of some common sunlight analysis methods base on CyberCity GIS, including 3D dynamic shadow and the sunlight time's calculation of every kind of single point complex building at different districts in different seasons. Compared with 2D sunlight analysis, imitating certain day's shadow changes in 3D scene is more lively and more visualized. For the building's real position, height and roof's shape, the calculating result is more precise and reliable. It can provide a quick and certain scientific analyzing method and accurate data for urban plan departments, urban plan designers and citizens.At the end of the paper, the author introduces the applications and the realization of the sunlight analysis system CCSunLightAnalysis based on CyberCityGIS software, and prospects the development of the sunlight analysis software.