Technical Research On The Integration And Dynamic Response Of 2D Information And 3D Information

In recent years, with the rapid development of computer technologies, having injected new vigor into 2D electronic map, the 3D electronic map based on 3D virtual scene is becoming an important direction of electronic map development, but the 3D virtual scene can not totally replace the 2D electronic map, the perfect solution is the integrating organically of them. The dynamic response between 2D electronic map and 3D virtual scene resolves the limitation of them, which combines the advantage of 2D electronic map—macro view, whole, concise and the advantage of 3D virtual scene— local, realistic, living , at the same time overcomes the abstraction of 2D electronic map and wandering astray of 3D virtual scene. It can make them have complementary advantages through merging, realize the two-way communication. There will be certain practical value in the fields of urban planning and construction, city traffic etc.This thesis proceeds from concept of the electronic map and analyses in the characteristics with 2D and 3D information, probes into the relations between them, it analyses the basic principle and expressional form of dynamic response and designs procedure and accomplishes display and some editing function of 2D electronic map through visual programming, presents the solutions for some key technologies that are needed to construct virtual scene, such as technique for terrain and terrain features generation and method of scene structure, simplified DEM data are used to construct terrain frame at first, then fractal is used to generate the details of terrain, it reduces the input of the data, saves systematic resources, decreases the delay of real - time generation and to ensure the realization of real - time interaction, then reveal 3D virtual scene through 3D visualization, reaches integration of the 2D and 3D information.This thesis carries on deep research to the key technology of realizing responding function emphatically, provides the concrete solution of view point position, study 3D coordinate inquire technology and OpenGL offer pick up and feedback mechanism, have realized the inquiryfunction of the 3D coordinate, the key problem lies in Z of view point, utilize the present view point confirm on which surface piece of topographical net in form, and then get the Z coordinate value by way of inserting value, and then confirm the high value of the view point, reaches integration of the 2D and 3D information;it discusses the modeling technology and visualization of the 3D Virtual Scene. Finally, the thesis integrates a system of dynamic response based on VC++ platform and Vega API.