海量散乱点的曲面重建算法研究

基于海量散乱点的曲面重建在机械产品测量造型、计算机视觉、根据切片数据的医学图像重建等领域中有重要应用.给出了一种以物体表面上不附加任何几何和拓扑信息(包括测点法矢、曲面边界信息)的散乱点集为处理对象,自动生成物体表面的三角网格模型的算法.该算法首先根据测点的邻近测点估算曲面在该测点处的法矢,并采用优化的顺序对法矢方向进行调整以使各测点处的法矢都指向曲面外侧,最后用步进立方体算法输出三角网格模型.采用新的方法计算切平面,不但进一步提高了效率,而且改善了曲面边界及尖锐棱边区域的重建效果.还提出并解决了法矢方向传播中可能出现的局部“孤岛”问题.同时，提出了一种对海量数据进行空间划分的算法,从而大大提高了海量数据的处理效率.应用实例表明,算法效果良好

Algorithmic Research on Surface Reconstruction from Dense Scattered Points

Surface reconstruction from dense scattered points is of great importance in a variety of situations such as reverse engineering for mechanical products, computer vision and of biomedical images from two-dimensional contours. In this paper, the authors present an algorithm to automatically reconstruct triangular grid representation of a surface from scattered points. The source data may include no additional information other than coordinates of the measured points. In the algorithm, tangent plane of the surface at each point is first calculated according to the point and its neighbor points. In an optimized sequence, normal vectors of the tangent planes are oriented to the outside of the surface. Finally, marching cube method is used to output the triangular representation of the surface. The method put forward to calculate the tangent plane not only promotes the efficiency but also improves the reconstruction effect, especially in the boundary areas and/or sharp arrises. The problem of ‘isolated island’ probably encountered in normal vector propagation is settled. The spatial partitioning scheme put forward in the paper greatly improves the efficiency of the algorithm. Results of the examples show that the algorithm is satisfying.