Nurbs-based 3d Terrain Modeling Study

People living on Earth linked to the Earth's surface everywhere. However the Engineers, Surveying and mapping workers have Different areas of expertise and study focus on different, but they all share a common hope what find a convenient and accurate way to express the actual surface phenomena. AS the continuous improvement of China's water resources and hydropower engineering and the rapid development of hydropower projects, three-dimensional geological modeling and analysis has been extensive and close attention. NURBS is the 1991 International Organization for Standardization (ISO) issued an official definition of industrial products, geometric standard STEP. As a product of international standards for data exchange in STEP standard, free-shaped curves and surfaces using NURBS said that the only.In this paper, we can think from another perspective that is NURBS surface modeling approach, considering the function parameters of the model applied to the three-dimensional terrain modeling to make the model made with a small amount of storage, the only guarantee of space Geometric invariance, etc.In this paper, the introduction of technology constructing NURBS check Mijiao River Hydropower part of the regional terrain contour as the raw data to study the establishment first and Builded the River TIN model, and then reverse engineering their train of thought NURBS Terrain model, and 1:5 million and the terrain model were compared.In this paper, the better the completion of the study and exploration of three-dimensional terrain modeling tasks expected of the new method, the paper Theory and Practice of Water Resources and Hydropower Engineering for the three-dimensional terrain model of the new method of study provides useful reference.