Research On 3D Visualization Of Underground Pipeline

Underground pipeline is a kind of important infrastructure of modem city. It takes on some important basic work, such as information and energy transmission. Because pipelines distribute underground, planar graph can not express the distribution intuitively. Through figure map only, we can't realize spatial disposal of underground pipeline up and down. It's very inconvenient for us to process construction and maintain pipeline. So we use 3D visualization techniques to resolve the problem.Firstly, the research background of Underground pipeline 3D visualization and current research status of domestic and abroad are described, with discussing the basic problems of Underground pipeline 3D visualization. Besides, a brief introduction of the main research work in this dissertation is also given.Secondly, the concept of spacing data indexing and its main algorithms are introduced with emphasis on the R-Tree indexing structure, and the way of utilizing of the characteristic of underground pipeline data to build the indexing of underground pipeline database is introduced.Thirdly, the method of underground pipeline topology presentation is studied. Using pipeline topology presentation, we can manage and express the pipeline data more effectively and intuitively, and provide the foundation of further application. The basic idea of topology expressing is abstracting the underground pipeline as graph, and treating the equipment as vertex of the graph and the pipe as edge of the graph. Also, the method of implementation the topology presentation based on Boost Graph library is introduced.Finally, a pipeline visualization system based on VTK is implemented. The visualization of pipeline consists of three parts: 1, transform the graph presentation to VTK internal data model; 2, the presentation of pipe and its visualization method; 3, the presentation of equipment and its visualization method. In the visualization process, the pipe is treated as tube, and the algorithm of tube generating is studied, the equipment is placed at its corresponding place, the methods of equipment modeling, loading and visualization are introduced. At last, some problems concerned about speeding up visualization interaction and better user experience is discussed.