Research And Implement On Desktop Virtual Museums Walkthrough System Based On OpenGL

The virtual walkthrough technology is an important branch of the virtual reality technology, it has great development in a variety of industries such as aerospace the construction, tourism and games. Virtual museums walkthrough, which is the combination of virtual modeling technology and virtual museums walkthrough technologies, is a representation of the virtual walkthrough technology. Virtual museums walkthrough system will allow tourists to view the famous scenery of the world at home, shows the world's amazing changes to the people, and supports people with a large number of science, knowledge at the same time of entertainment.There are certain technical problems in the present virtual scene walkthrough system including the contradiction between fidelity modeling and real-time rendering of scenes, between the simplicity of the bounding box and wrapped, it is important to improve the application effection and the quality of walkthrough system by balancing and reducing contradiction between them.Basis on the virtual museums walkthrough technology, this paper present a virtual scene data structure based on OpenGL, establish the method of the corresponding collision detection. This method defined the object for each model in scene by introducing the concept of Object-Oriented. In the realization of system, this paper firstly established AABB object axial bounding box for each object, and then constructed Octree structure for the whole scene by the root bounding box. Based on the object Octree and AABB level bounding box, a data organization model was formatted. Since the users are allowed to use the third person perspective walkthrough, it is necessary to consider collision detection problem between Avatar and objects in scene. Traditional approach is to use the Round-Ball to wrap the Avatar, however, the closeness between spherical bounding body and Avatar is poor. In this paper, capsule bounding body was used to instead spherical bounding body to do the collision detection. Based on the previous data structure, an improved roaming Collision Detection Algorithm is achieved.According to the experiment results and the real application, the Object-Based Octree AABB level bounding box and integration of the model not only can solve the problem of dynamic changes of scene, but also provide a reliable and effective way to the organization and management of scenes, overcome the defects of pure Octree and AABB level bounding box structure. Based on this data scene of the organization structure, the collision detection algorithm can solve the contradiction between the closeness of bounding and simplexes of bounding box, effectively improve the accuracy of collision detection.