3D Graphics and Virtual Reality Applications in Decision Support System
3D Graphics and Virtual Reality Applications in Decision Support System
Ms. Zhu Xuan
Abstract
The visualization of 3D terrain can be used to reveal the information and synthetical character of 3D terrain directly and actually. It is widely used in many fields. And it has broad practical foreground. With the fast development of computer technology and the specialization trend of 3D GIS, 3D terrain visualization has become the foreland and focus subject in the water related area; it can show out the change of the critical area in the dynamic way and can help people to navigate into the landscape in order to have an overall view of the area.
Base on lots of advanced results of computer graphics, modern mathematics, virtual reality and topography, etc. This thesis discusses the theory, techniques and arithmetic of 3D terrain visualization implementation based on OpenGL, detailed including the basic theory of 3D terrain visualization, 3D geometry sculpting technique, the means of curved surface fitting of discrete data, the principle and the related techniques of OpenGL, the main style of DEM, the implementation theory of the 3D graphics, the query techniques of 3D coordination and the interaction of person and computer.
At last, based on the researched result of above theory, based on WINDOWS XP system and Visual C++ 6.0, the 3D terrain simulation system using OpenGL has been established. The system can receive and process the ASCII format DEM data which can be generated from the ArcGIS, realize different 3D pattern visualization mode of line, laminated colours and texture file showing, etc. and has the function of real time dynamical browse , 3D coordination query, grid data and 3D figure export etc. It has the function of 3D contrastive figure drawing and contrastive data export of alternative terrain.
This investigation has important theoretic and practical meaning. In theory, we investigate the data structure and designing terrain. In practice, it is the basic of the global realization and 3D GIS introduction; it is the key to realize the 3D visualization map; it is important in the ‘digital earth’, and provides an archetype system for the 3D visualization system in water related area.
Key words: 3D visualization, 3D terrain, OpenGL, DEM, 3D coordinates query, Navigation