| Virtual Reality Technology is a newly applied technology and it has beenused in many fields.It concerns many subjects like Computer Graphics, ArtificialIntelligence, Multimedia Technologh, Man-machine Interface Technology andso on. So far, VR technology has been applied to many fields, including medicaltreament, education, entertainment, CAD/CAM, archetecture design and so on.Virtual Reality has became one of the most important computer appliedtechnology.Real-time walkthrough technology in virtual architecture is the syntheticalapplication of Virtual Reality Technology for demostrating, validating andevaluating the technologic production of city planning, architecture designingand reality developmenting. They will bring the innovatory development inrelative fields.Technology of building of realistic virtual scene is the key technology ofVR.In this thesis, we research the relative 3D graphic principle on buildingrealistic virtual scene mainly including graphic transform thechnology,perspective transform technology, model and shading technology, and texture mapping technology etc.Firstly, we use OpenGL to render simple model in virtual scene baseed onvertices and polygons. This method of rendering is mainly used in the buildingof simple virtual scene.Then we build other complex models in virtual scenewith aid of special modeling software such as 3DS Max and put these modelsinto the virtual scene.At last we build the realistic virtual scene, which can beman-machine controlled.Technology of accelerating the rendering speed of virtual scene is other keytechnology for real-time walkthrough in virtual scene.In this thesis, we study theprinciple and application of technology mainly including Spatial Data Structure,Culling Techniques, Level of Detail(LOD), Display List and algorithm ofscheduling objects in virtual scene.we introduce a algorithm of schedulingobjects in virtual scene based on area and focus of vision and realize smooth andun-delayed walkthrough in virtual scene.In the thesis, after summarizing the algorithm of collision detection webring forward the algorithm of collision detection applied in the virtualarchitecture scene. The algorithm has been implemented in the walkthroughsystem.Using OpenGL and C++,we realize the real-time walkthrough system of ahouse.At last, we summarize the work of this thesis and discuss the potentialresearch topics in the future. |
