一种河口湾海岸线渐进化简方法

形态复杂的河口湾海岸线自动化简是当前线要素化简研究的难点之一。在现有研究基础上，结合地理特征影响下河口湾海岸线形态特点及海图综合约束，提出一种河口湾海岸线渐进化简方法。该方法以约束Delaunay三角网为支撑构建河口湾骨架线二叉树模型，结构化表达河口湾海岸线形态特征；基于此模型，通过叶子流路渐进取舍、"退化"充分化简细小弯曲或弯曲细小部分，通过局部夸大消除河口湾内视觉冲突等，实现河口湾海岸线化简。试验结果表明，该方法充分化简目标尺度下不可视的局部细节，顾及河口湾海岸线整体形态特征保持，在几何层次、地理层次上都具有一定优越性，适于多种形态河口湾海岸线化简应用。

A Progressive Simplification Method for the Estuary Coastline

Estuary coastline simplification is one of the most difficult research of linear features simplification.Having analyzed current researches,a new progressive simplification method for estuary coastline is proposed,considering that representation characteristics influenced by geographical features and rules of chart generalization for coastlines.Firstly,a binary tree of estuary skeletons is structured by Delaunay triangulation network to represent the pattern of the estuary coastline.Secondly,leaf streams of the structured model are removed or partial removed gradually to simplify small bends and parts of the coastline enough.Thirdly,narrow details of the bends-simplified coastline are exaggerated to avoid visual conflicts of the estuary.Results of experiments show that small details,invisible at the target scale,of coastline are simplified enough by the proposed method,while pattern features of the original estuary coastline are preserved.Besides,the proposed simplification method has advantages in both geometry and geography.Additionally,it is suitable for the proposed method to simplify various estuary coastlines in applications.