Research And Development Of Realtime Roam System In 3D Environment Based On Virtools

Virtual reality technology can generate actual simulation environment by computer that enable users immersed in the virtual environment, at the same time, users can direct interact with the virtual environment through man-machine interface. Three dimensional scene roam system is better then traditional printed map and animation effects in immersion, interaction and real-time. Currently, virtual reality technology being widely used in military purposes, entertainment, manufacturing, medicine, geographic information systems and other fields, as a new branch of science , with the unique advantage.Three dimensional scene roam system is an integrated application of virtual reality technology, the most difficult point is reality sense of model rendered in system scene and real-time rendering efficiency of model. To ensure the rendering quality and not bring uncomfortableness when user roams in the scene,we should adopt excellent modeling and reduce the complexity of scene, at the same time adopt scene optimization technique to improve system to execute efficiency.First, the article introduces virtual reality technology and three dimensional scene roam technology, and analyses three kinds of three dimensional scene roam technology, at the same time discusses the three dimensional scene modeling technology and he three dimensional scene optimization technology, and deeply investigates the LOD technology of scene optimization technology as well as producing possessive LOD model technique based on the possessive mesh arithmetic,the LOD technology controls the complexity of the scene, thereby improve scene rendering effect and roam system reality. The article dose research of particle produce, acting, death based on the particle system theory which describes abnormity, at the same time predigests the physical property of snow particle, controls particle number, satisfies the realtime require. At last, we imply the factory roam system by 3DSMAX modeling and developing roam engine based on Virtools, and imply LOD predigestion technology based on the possessive mesh predigestion and snow and rain effect based on particle system in the system, the effect is satisfied. The roam system implies viewpoint forward, backward, left or right translate, left or right orate, upward, downward, auto roam, free roam, the record and replay of roam process, period of time variety, weather variety and the on/off control function of background music, all of these supply better interactivity for the roam system.