The 3D Model Simplification Technology In Virtual Reality

Virtual Reality, as the most powerful technology of human-computer interaction, has always been one of the spotlight of information field research and application. However, to the development of Virtual Reality, real-time rendering 3D graphics is a key item, because large-scale 3D real-time interaction of virtual scene is related to interactive display of complicated geometry model. Out of the need of reality feeling of virtual scene, the model is more complicated than the ability of real-time drawing of the current high-quality computer system. On the other hand, with the rapid development of computer technology in several decades, the software and hardware technology has been increased in large scale. For raising the software portability in this trend, the graphic data models are indicated by floating point numbers, the related processing calculation no longer demands integer computation, all kinds of the simplified calculation of LOD is based on float computation. So, when dealing with large-scale 3D data model we have a high-quality requirement to the computer hardware.Therefore, how to improve the drawing speed of large-scale complicated scene and then realizing complicated data real-time interactive display, has become the present spotlight in computer graphics.We can use certain technology to be in charge of the model of the scene to gain ideal visual effect and computer processing. The LOD is commonly used at present. That is to say, the 3D objects are displayed in various precision and choose various precision model to form image according to the position variation of the viewpoint.It can be seen that the simplification of 3D complex model is one of the key factors affecting entire Virtual Reality system. It also means that we need simplify the model as possible as we can and delete the vertex and the face of the model without affecting the graphic accuracy and make it real-time display in high speed and without distortion.The research of the thesis is about the simplified calculation of 3D model based on Virtual Reality system. At first made a overall introduction of Virtual Reality system, then introduced the most currently-used 3D graphics file. In order to make easier processing, the chapter also defined a special 3D file format and supply a method for process. Afterwards described LOD technology in details and gave more emphasis on Edge Collapse algorithm, then programming and gave a test analysis of the program. Lastly put forward a model simplified calculation based on Device Coordinate System and without float computation, then gave a test analysis of this calculation.