导航电子地图多尺度显示与载负量的研究

导航电子地图的多尺度显示目的就是在导航终端有限的屏幕容量下．形成适宜载负量的地图。本文在对导航电子地图载负量指标进行研究的同时，将导航电子地图用于显示的道路形状数据、背景数据、地名数据，按照每一类要素的几何大小或重要程度再分为若干级别，利用分级显示技术，计算出导航电子地图各级显示尺度下的合理载负量，使导航电子地图在多尺度表达时显示要素载负量合理、分布均匀，尺度切换时鼐示要素过渡自然、流畅。

Research on Multi-Scale Display and Map Loading of Navigation Electronic Map

The navigation electronic ,nap＇s multi-scale display is used to attain appropriate amount of map loading in the navigation terminal which has limited screen size. In this paper, navigation electronic map＇s loading indicators are researched, and a navigation map display data set of road shape data, background data and place point data are further divided into several levels. According to the size of each type of geometric element or degree of importance, using of hierarc, hical display technology; the navigation electronic map＇s reasonable loading is calculated at all levels. The map loading is ensured reasonable and display elements are distributed equably in muhi-scale representation. The display elements are ensured to transform naturally and smoothly when map scale is changed.