Extended Research On The 3D Terrain Enviroment Based On Open Source Virtualization Engine

With the half century development, geography information system experienced the steps of desktop geography information system, embedded geography information systems, network geography information systems. Under the wave of the technological innovation, the new theoretical and technological system is increasingly emerging, such as virtual geographic environments, three-dimensional geography information system etc.Database and model base is the core content of the virtual geographic environments.The geoanalysis and geographic modeling theory is still in development stage. In this paper, beginning with the terrain model, we elaborate two kinds of foreign Terrain Algorithm called FaultFormation and MidPoint Displacement and triangular mesh rendering algorithm called Brute Force Algorithm. The paper uses the open-source virtualization engine OpenSceneGraph as visualize engine, which can realize the development and implementation of the three-dimensional outdoor scene (terrain) from the standpoint of the virtual scene, and theoretically analyze two kinds of terrain. At the same time, we also develop a series of project examples by using open-source sound library Fmod and physics engine called ODE. Based on the terrain construction and the related theories of computer graphics, we study and develop a three-dimensional label model independently which combined with the terrain model matching with high precision and finesse.Aiming at the study of terrain algorithm , virtualization engine and physics engine, the paper partly introduces these theories of virtual geography, computer graphics, virtual simulation and program designing, which can be the footstone for the future study about the virtual terrain environment and the foundation of theory and technology for the future work.