Subnet convex hull merging algorithm for reconstructing digital terrain models
ZHENG Jitao1,2, HE Honghong2, ZHANG Tao2, ZHU Jihong1
1. Department of Computer Science and Technology, Tsinghua University, Beijing 100084, China;
2. Beijing Aviation Meteorological Institute, Beijing 100085, China
Abstract：There are many digital terrain reconstructing methods based on divide and conquer. This study analyzes all possible cases of the merging of two subnet convex hulls. A subnet merging algorithm is then developed to overcome the limitations and drawbacks of traditional algorithms. The public support line and support points are found from the projection position of the vertices of the convex hulls. Then, the convex hull vertices between the support points are linked to generate new triangles so that no two triangles are intersect. Tests show that the algorithm is stable and reliable and that any two subnet convex hulls can be successfully merged.
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2015, Vol. 55 
