Research And Implementation Of Spatial Analysis In The Virtual Urban Simulation Platform VRGIS

The virtual reality technology has been more and more widely used in social life, and is more and more widely applied in the field of urban construction.The development of virtual city technique and social need poses higher and newer request to GIS spatial analysis.But most of the systems usually focuses only on 3D representation of the scene and ignores the research and development of 3DGIS spatial analysis,operations such as spacial object inquiry and spacial analysis cannot be well satisfied,either.Therefore the seamless integration of the 3DGIS and virtual reality technique is an active area of current research.To achieve stable,efficient and useful spatial analysis function,so as to realize close integration of VR and GIS by researching on spatial analysis algorithms is the main purpose of this thesis.By studying the basic spatial analysis algorithms and typical methods for urban construction and development,this thesis can provide scientific and practical decision support to the solution of the space-related problems in human lives,this thesis mainly researches the following:1.This thesis has studied the basic theory and methods of the spatial analysis, the content,methods and model systems of the spatial analysis have been systematically summeried.2.This thesis has studied the organization of spatial data model,it firstly studies the representation methods of spatial data,then introduces the concept of the bounding box and quad-tree,the organization method and its advantages.3.For the needs of analysis of three-dimensional space,a large number of spatial data structures and mathematical libraries have been defined,the research and development of a number of highly efficient algorithms based on spatial analysis have laid a good foundation for more complex spatial analysis. 4.Based on the study of algorithm and spatial data organization,a series of spatial analysis methods have been realized,a good spatial analysis module has been produced,mainly including the spatial query,analysis of measurement(distance measurement,area measurement and the volume measurement),spatial dynamic positioning,terrain analysis(flooding analysis,earthwork volume analysis,contour analysis,section analysis,visibility analysis and terrain leveling),sunshine analysis, eagle eye analysis,greening ratio analysis.The module of spatial analysis has been integrated into the self-developed VRGIS platform,then the experiment and application have verified the correctness and reliability of the algorithms and methods in this thesis.