Lake Automatically Integrated Research And Realization

The evolution of the computer technology facilitated the development of cartography, and caused a huge revolution of various technique of cartography. It also made GIS gradually penetrate into each section of the national economy and play an important role in it. While the request to the geography information data of each section is so different, and it always needs various scale of the geography information data of the same region. However the collection of the geography information data needs lots of manpower and material resources, repeated saving and managing data of various scale also means huge investments of economy and manpower depletions. And it's hard for us to make sure of the consistency of these geography information data.Hydrograph is very complex among map elements and has various varieties. Since lake is an important part of hydrograph, the researches on the generalization of lake affect other elements' generalization. So we need a valid way through which we just need to collect and save a possibly detailed geography information data of a certain foundation scale. On base of these we could obtain the data of other scales by generalizing. As an important part of GIS, lots of researches have been done on generalization by specialists and also have acquired some achievements.This article analyzes research status and key problems of automatic generalization. And on base of the characteristics of lake the text carries on analysis and implementations to the generalization of lake's morphological characteristic and distribution characteristic of lake cluster combined the request of item. Then the article describes structured generalization of lake cluster using operations of spatial cluster and hull of computational geometry and etc. And it carries out an algorithm named snake that derives from energy minimization theory to simplify the contour line of lake. Snake algorithm can preserve the whole morphological characteristic of area feature during the course of simplification of its contour line.