摘要：

针对海量三角网地形分块绘制中出现的裂缝问题,在地形特征的基础上,提出一种基于数字高程模型(DEM)分辨率动态添加共享边界点的方法。采用盲人寻径法快速求得地形块边界点,根据DEM的分辨率动态确定内插点间距,计算相临地形块边界宽度值和交界有效长度。根据内插间距与交界有效长度计算出需要添加的边界共享数据点数,使得各级分辨率的共享边界点都保持一致,从而适应地形多分辨率绘制要求。测试结果表明,该方法在保证地形绘制精度的前提下,有效消除了不规则三角网海量地形绘制的裂缝,且能够解决不同分辨率地块裂缝的消除问题。

关键词: 海量地形, 裂缝消除, 地形特征, 不规则三角网, 动态处理

Abstract:

In order to solve the problem of cracks in massive triangular network terrain block rendering,a method of dynamically adding shared boundary points based on resolution of Digital Elevation Model(DEM) is proposed based on terrain features.The boundary points of terrain blocks are obtained quickly by the blind path finding method.The interpolation point spacing is dynamically determined according to the resolution of DEM,and the boundary width and effective length of the adjacent terrain blocks are calculated.Then,according to the interpolation spacing and the effective length of the boundary,the number of shared boundary points needed to be added is calculated,so that the shared boundary points at all levels of resolution are consistent,so that they can meet the requirements of terrain multi-resolution rendering.Test results show that this method can effectively eliminate the cracks in massive terrain rendering of Triangulated Irregular Network(TIN) under the premise of ensuring the accuracy of terrain rendering,and it can also solve the problem of crack elimination in different resolution blocks.

Key words: massive terrain, crack elimination, terrain feature, Triangulated Irregular Network(TIN), dynamic processing

中图分类号: 

• TP311