Abstract:
In order to improve the efficiency of constructing the Delaunay triangulation of the plane point set, a parallel algorithm for constructing the Delaunay triangulation with the adaptive dichotomy of the point set and parallel triangulation for subset is presented. Firstly, the guild line for the point set bipartition is constructed based on the geometrical distribution of the point set. Secondly, the Delaunay triangulation growth algorithm with priority point as the center is adopted to construct triangles along the guide line, and thus the point set is divided into two subsets according to the position relationship between the points and the triangle. Then, the parallel bipartition for each subset point set is performed until the number of subset meets the given threshold value. After that the Delaunay triangulation of the sub-point set is constructed in parallel. Finally, the constructed triangles from the adaptive dichotomy step and Delaunay triangulation for subsets are gathered into global triangulation. Experiments with different point set sizes and different segmentation thresholds show that the presented algorithm significantly improves the efficiency of triangulation. When the threshold of the number of the point set is 900, the triangulation time of the proposed algorithm tends to increase linearly with the size of the point set. When the size of the point set is 30 000, the average promotion efficiency under different segmentation thresholds is 66.11%. The presented algorithm takes full advantage of the locality and globality of Delaunay triangulation to ensure that every triangle constructed in the adaptive dichotomy or parallel triangulation for subsets is the final triangle, which can effectively improve the efficiency of network construction. At the same time, the presented algorithm also provides a feasible scheme for constructing the local Delaunay triangulation of the point set.