Research On 3D Building Simulation And Walkthrough Based On OpenGL

The Virtual Reality is one kind of technology that produces a highly realistic simulation environment by using computer to make user immerse into the virtual environment by some kinds of sensor interface and accomplish interaction between user and environment. Currently, Virtual Reality technology has been widely applied to various fields. In the architecture industry, we can use a computer to create simulation of buildings and create a series of three-dimensional architecture models, and we can roam the building by I/O devices of computer, so that users may have some ideas of building without going to the site, or before it finished.OpenGL is a 3D graphics software package in common use, based on Computer Graphics, consistent with the principles of optics and vision. It provides very rich interface functions, which allows the user to create an interactive process, generating a series of 3D graphics, and their control.In this paper, I will do some research about Virtual Reality and the related 3D Computer Graphics theory. Based on the research, a system on building simulation and walkthrough will be developed, using OpenGL and MFC framework of VC++. The system has a friendly user interface. The main achievements of this paper include:1.Make some analysis about OpenGL programming and working theory, including hardware realization and software realization of OpenGL, the pipeline of rendering in OpenGL and different modes of drawing graphics, main functions of OpenGL and so on. Make an introduction about VC++, at the same time summarize programming principles of MFC and application framework.2.Make some analysis about data feature of virtual building and how to import external 3D model file, which is formatted with 3DS, including analysis about chunk structure of 3DS document and recursion functions of programming and data structure of redrawing model. Do some research on color model, light model and texture mapping in the process of generating realistic 3D graphics, such a series of technical issues, and their realization in OpenGL.3. Do research on 3D viewing pipeline applied in the module of roaming the building. Such as how the situation of objects alter while viewing and how the function realize in OpenGL. Based on that, a class named "camera" in the code will fulfill roaming function.4.Develope a system on building simulation and walkthrough based on MFC and OpenGL. In the system we can import external virtual building model, and add lights, materials and textures for it, to make it more realistic. And the system provides simple roaming function, allowing users to view the building from all angles.