Visualization For Roof Net Construction Of Shenzhen Civil Center

This subject comes from the project of the large roof net construction of Shenzhen civil centre monitoring system. The main content of this paper includes correlative technologies to build multimedia environment, some algorithms to visualize the result data of finite element analysis of large roof net and extensible interface technology.1. Framework of structure stress analysisStructure simulation analysis consists of three necessary conditions that are constitutive relation of material, proper numerical method and rich graph display software and multimedia environment. The combination of the correlative technologies of the third condition and the result data produced by the other tow conditions composes the basic framework of structure stress simulation.2. Key technologies of building multimedia environmentIn multimedia environment, users can interactive handle various multimedia information which includes text, graphics, image and sound etc. Multimedia environment integrates multimedia information and builds logic link between them.To build multimedia environment, OpenGL technology, DirectSound technology and creating and playing AVI video technology are analyzed in detail in this paper.3. Visual algorithm research of structure stress result dataThe post-processing of structure stress result data means to visualize the result data of finite element analysis software and model test with scientific visualization technology. The visual display of the result data includes structural deforming graph, animation simulation, three dimension image, contour, isosurface and cloud map etc.In this paper, a volume rendering algorithms is discussed. The algorithms how to create structural deforming graph, animation simulation and contour arealso introduced.4. Data interface technology researchCOM is programming language-independent, inheritable and transparent for process and can be reused in binary level. By using COM, the problem that the output of finite element analysis software and model experiment has no coherent file format is solved. When correlative software is upgraded of the output file formats are changed, the output file still can be used just by upgrading COM interface.Several file formats include DXF and 3DS are analyzed and programmed COM interfaces.5.The design and realization of systemThe system designed by using object-oriented design method and Data base technology in OpenGL environment, and then the user can read their needing data in visualization form at front, and all danger information and data of nodes and bars of large roof net keeps in the backstage database.