Application Of Virtual Reality Technology In Visualization Of Urban Underground Space

With the continuously development and innovation of the computer science, computer graphics, and modern mathematical theory, combining with virtual reality (VR) technology and scientific visualization (SV) technology, the 3D modeling of the underground space is gradually becoming a hot spot in the field of geology research. As the basis space of human survival and development, it's very important to exploit and use the underground space of urban rationally. Through some data of the geological survey and flat network to build 3D model of the underground space, makes us understand the structure of the underground space and the distribution of the flat network space more clearly, it provides a powerful assistant tool for the decision of geological survey and maintenance of the underground pipeline, thereby ,the limited resources of urban underground space can be developmented and utilized rationally.The paper focuses on the development of the three-dimensional visualization software of urban underground space,taking the Tianjin Institute of Urban Construction campus as the example, using VC + + platform, the visual simulation tools Multigen Creator ,Vega Prime and their application Programming Interface OpenFlight API and Vega Prime API , dynamic building of three-dimensional geological model and urban underground pipeline model based on the borehole data and network distribution map is realized. And real walkthrough, mutual and query of the three-dimensional information are also realized. The following aspects were discussed in this paper:1. The 3D environment of campus'scene was constructed by using the professional modeling software- MultiGen creator and Photoshop CS. The scene integration , attemper manage and optimizing the technology and approaches of 3D model are researched.2. Multi-layer DEM surfaces modeling method, which Based on borehole data was reaserched.Combining with Multigen OpenFlight API, the 3D geosciences modeling database file is generated to realistic 3D stratum modeling. The key technology,which realized building 3D pipe network model throught 2D network plans automatically on the basis of the B-Rep modeling method is reaseached. And dynamicly building of model based on the network data is realized. At the same time, ground landscape model, underground stratum and pipeline were integrated in the virtual scene by programe. Finally, combining OpenFlight API with VegaPrime API , 3D geosciences and pipeline model were edited and loaded dynamicly in the walkthrough condition.3.The driving and information inquiring of model,which under the MFC framework and Vega Prime application program as well as the realization of the 2D navigation map in the 3D scene were researched. At the same time, the interactivity between 2D and 3D in the virtual roaming was realized.