Complex Scenes Really Three-dimensional Geometric Expression

On the base of studying and making some nanalyses about the status quo of the three dimension laser scanning technology both the internal and the external, combining with the significant scientific research of Beijing: service system of three-dimensional spatial information of Beijing, the author successed in researching into the ways on actual three-dimensional geometry representation of complex scene. All of the above work is in the need of the practice in the domain and is by the synthesis of several technology, such as virtual reality, computer vision , solid geometry and other relative technology.The contribution of this thesis can be summarized as follow:1. Brought forward the ways on the optimizing of three-dimensional data, including extracting extent that we are interested in, the repairing hole of data and smoothing and provided preparative for data process.2. Aiming at laser three dimension scanning data, brought forward a simple and effective way on preparatory constructing of gridding.3. Designed a simple and effective scheme on the compressing of gridding data. Reserving the local details of models and being capable of controlling freely the compression ratio, the scheme is realized.4. Realized the texture mapping and showed the satisfactory visualization.In conclusion ,by plentiful experiment and programme simulating, the research successed in reconstructing three-dimensional model based on point cloud and providing a suit of digital resolvent for actual three-dimensional geometry representation of complex scene. At the same time, this successed in providing to a certian extent technology accumulation and preparative for homegrown development of laser three-dimensional data process.