Research And Application Of Multi-User Virtual Reality System Based On B/S Architecture

Now with the X3D technologies become more and more sophisticated, and the birth of a variety of Web application technology, the demand for opening a web browser can be roaming in a large virtual world like Second Life (Second Life) become eager and eager. Multi-user virtual system which based on B/S structure is gradually into the industry's attention. On the other hand, a multi-user virtual system based on B/S structure has many advances like:the code's size of virtual scenes is very small; users do not need to download the client-side software; last but not the least, it's easy for and maintain expansion, so these systems has enormous economic and applications prospects.However, the virtual scene can only be played by web browser's plug-ins which is made by a third party rather than the Web browser itself. When the user login, the plug-in will load the scene into its own virtual environment scene context object. Users actually access the server copies the virtual scene. At this point, the browser plug-in plays as a container to make the users to isolate and become a communication barrier between users. In addition, the characteristics of B/S structure make it difficult to send message between different users who log in the server. And this becomes a new subject in the industry.First, this thesis introduces three technologies which are closely related to the system design:the first is the X3D language, highlighting the grammatical structure of X3D, animation, prototype nodes operating mechanism. Second, introduces the SAI's organizational structure and in-depth analysis of the SAI's operating mechanism, including mechanisms for internal access and external access. Finally, make a brief overview for thinking of Ajax, and make an example describes how the combination of Ajax and X3D-Ajax3D works.Second, this thesis studies the method of how to constructing the virtual human movement, including:capturing method for kinematics, dynamics kinematics and key frame interpolation methods. And proposed a simple motion capture combines with key frame method for constructing a walking virtual human. The method is characterized by small costs and has some degree of verisimilitude. Meanwhile, the paper analysis the advantages and disadvantages of three-dimensional scene optimization strategy, and then designs a scenario optimization algorithm, and also made a number of effective strategies for how to improve the efficiency of the virtual systemFinally, analyses the needs of multi-user virtual system, and then describe the system business logic and technical indicators. Completed the design of the system database, message mechanism in, virtual people control and scene divider class. Also give the codes of detail for some of them.