多条海岸线协同化简的层次化三角网分区法

针对当前海岸线自动综合方法仅考虑单条线要素,未有效考虑其与附近海岸线之间的空间邻近关系,提出一种用于多条海岸线协同化简的层次化三角网分区法。首先,利用约束Delaunay三角网对能否化简的区域进行划分和标识;然后,利用二叉树构建层次关系模型,对各区域实体进行有序组织;最后,有序地对可化简的标识区域进行渐进式化简,并对局部狭窄区域进行自适应夸大,从而实现多海岸线的协同化简。试验结果表明:本文方法可克服复杂区域海岸线化简产生的图理性问题,可明显提高海岸线的化简质量。

A collaborative simplification method for multiple coastlines based on the hierarchical triangulation network partition

The current automatic coastline generalization method only consideres one-line element, yet the relationship between the nearby elements is not effectively considered. Aiming at this, a synergistic simplification method for multiple coastlines based on the hierarchical triangulation network partition is proposed in this paper. Firstly, the constrained Delaunay triangulation is constructed to partition the regions that can be simplified. Then, a hierarchical binary tree model to structure the morphological characteristics of the above several coastlines and the spatial proximity between different coastlines is constructed. Finally, the small curved and curved invisible parts of the coastline are deleted according to the visual constraints, and the narrow part between the coastline itself or the different coastlines is exaggerated appropriately, and the automatic simplification of the coastline is realized. The experimental results show that relationships between the different coastline are considered, and the shortcomings of considering the coastline separately are overcome. Furthermore, under the condition of the multiple coastline in complex sea areas, the problem of collaborative simplification is solved, and the quality of the coastlines is improved obviously. The proposed method can be applied into more types of coastlines.