Research And Application Of Virtual Reality On Roaming System

Virtual reality technology is widely used in education, medical treatment,architecture, industrial design, military and other fields. Virtual reality mainlystressed two points: First, computer-generated virtual world (environmental) must beto give people a visual, hearing, touch, smell, and taste a variety of sensorystimulation of the environment; second is essentially a virtual reality system a manmachineinteraction system, and is an advanced man-machine interaction system.Both those shows virtual reality human-computer interaction is the core. Virtualreality has"3I"characteristics: immersion, interactive, and imagination, the otherroaming technologies and systems that can not be compared. It is this"3I"features tovirtual reality technology can be developed rapidly.The earliest application of virtual reality technology is a virtual roaming system;virtual campus is a virtual roaming system of practical application.In order to better planning and development of the campus environment,enhance the school profile and promote the development of distance learning,research based on virtual reality technology campus roaming system construction hasimportant practical significance. Virtual campus publishes to the Web, allowingvisitors to visit the campus in the scenery at the same time, understanding the schoolrelateddescription information to the construction of the digital campus to provide agood platform.In this paper, the contents of the study are: virtual reality technology, VRML(virtual reality modeling language), scene rendering, three-dimensional modelingtechniques, scene optimization techniques and collision detection techniques. Herefocuses on the three-dimensional modeling methods and optimization technology,which is discussed in detail VRML modeling, model texture mapping, level of detail (LOD) technology, currently roaming the more popular virtual reality system, relatedtechnologies.In a virtual scene, the model has two types: static models and dynamic models.In the scene, the more dynamic model, the greater the probability of collisions, thecomplexity of collision detection will be higher. Scene motion model can be dividedinto two kinds of rigid and soft bodies, rigid body shape after the collision occurredand is unlikely to change, while the soft body in the event of collision often deformed.Therefore, the soft body collision detection is much more complex than the rigidbody. Collision detection is a virtual roaming system, an essential part. The speed ofcollision detection to reach at least 24Hz,in order to meet the visual requirements.The principle of LOD is that when the distance between the model and theobserver is relatively small when the model is large, indicating relativelysophisticated model; with the growing distance of up to a certain distance, the modelof smaller, indicating relatively coarse model; as the distance continues to increase,but also reached a certain distance, the model has become very small, it shows a moresimple model (which can be a simple geometry). In addition,dynamic and static twodifferent models to take a different display. For the static model of comparative finedisplay for the dynamic model uses a rough way to display the same, but for fastmoving dynamic model of the model can be displayed using a more simple way.Through access to a large number of relevant information on the virtual realitysystem, related technologies roaming conducted in-depth study that, VRMLmodeling three-dimensional modeling language more than any other advantage, itsadvantages are:(1)VRML file can be applied to different platforms;(2)VRML can easily generate three-dimensional geometry;(3)VRML browser, mostly with the control panel, user-friendly operation;(4)VRML can make use of Script nodes, through the Java language (orJavaScript) programs written in a script to extend its functionality.(5)VRML can be a standard PC, to facilitate display.So, I mainly use the VRML (virtual modeling language), a combination of Canoma, 3ds max, and Java (or JavaScript), and the final design of a campus roamingsystem base on virtual reality technology.The article elaborated on campus roaming system design process, including thethree-dimensional modeling, modeling links, roaming settings (i.e., interactivesettings), system optimization, web publishing five parts. Detailed description of thebackground set the three-dimensional modeling, building modeling, modeling oftrees and complementary approaches, and some code; interactive setting in VRMLusing Java in two ways (that is, through internal and external programming interfacesScript node EAI); System Optimization using LOD node to achieve level of detaildisplayed, set the visual distance, split scene, and some code in specific ways; andweb publishing.The campus roaming system is characterized by the largest three-dimensionalmodeling using a variety of ways, which greatly reduces the complexity of the model;the model reduces the complexity of the improved rendering of real-time, the greatestdegree of balance between authenticity and real-time relationship. At the same time,will combine VRML and Java, through the Script node in VRML, using a programwritten in Java or JavaScript functions of VRML extensions greatly enhance thecampus roaming system, interactive performance.Through virtual reality technology, virtual reality modeling language VRML,scene rendering, three-dimensional modeling techniques, scene optimizationtechniques and collision detection techniques, I think, to study some more efficientsystem optimization algorithm, the practical application in the future moremeaningful and effective in improving the real degree and increase rendering speed.