Study Of The City Scene 3D Modeling And Visualization Techniques

As a node of Digital Earth, Digital City is an indispensable part of Digital Earth. The 3D modeling and visualization of city scene is one of the core techniques of Digital City and has a wide application in the fields of architecture, traffic, city planning etc. In the paper, the city scene modeling and visualization technique was researched. The main work is as follows:1. Based on the classification of the primary modeling objects in the city scene, we separately rebuild the model of the terrain and objects according to the 3D spatial data structure.2. The basic theory of 3D visualization is discussed, and the 3D stereo scene display is realized by using separate ray method. The rendering effect is improved by adopting the accelerating drawing algorithm and creating the especial sight.3. The 3D wandering engine is designed, the indoors and outdoor scene integrative wandering in the building is realized by the eye point switch and the 3D model web browse of Digital City is accomplished by the VRML technique.4. The 3D spatial object is picked up under the support of bidirectional coordinate inquiry in both the ground coordinate system and the pixel coordinate system and the spatial and attribute information of object is mutually inquired.5. The spatial analysis based on the 3D terrain map is realized and sunlight analysis of the buildings is achieved by strict sunlight model.6. A 3D visualization and information query prototype system of Digital City is established by integrating the algorithm in the paper and combining the correlative project.