基于区域聚合的栅格地形数据简化算法

Grid Terrain Data Simplification Algorithm Based on Area Aggregation

针对规则网格地形数据存在的数据冗余,提出了一种基于区域聚合的地形数据简化算法,区域聚合是将共面或近似共面的若干地形栅格点用这组栅格点的边界点代替。该算法用面元间最大法向量夹角余弦值作为简化度量误差,通过递归过程完成数据简化,结合简化后存留散列点的特点进行地形绘制且经过消除地形裂缝处理,避免了离散点Delaunay三角化过程。实验结果表明,算法数据结构简单,便于使用,简化精度可控,简化效果好。

Considering the redundancy of regular grid terrain data, the paper proposes a terrain data simplification algorithm based on area aggregation. Area aggregation means replacing the coplanar grid points by the border points. The algorithm uses the cosine value of the max angle between different normals as the simplification error measurement and accomplishes data simplification by recursion process. At last, the algorithm realizes terrain mapping based on the features of the remained hash point after simplification, and avoids the Delaunay triangulating process of discrete points by eliminating terrain crannies. Experiment results show that the method has simple data structure and has good effect in simplifying grid terrain data with controllable simplification precision.