基于Global Mapper的地貌晕渲制图——以西安幅(Ⅰ-49)为例

Methodology of Automatic Relief Shading Map Making Based on Global Mapper——Taking Xi'an Region (Ⅰ-49) as an Example

地貌晕渲图自动制图是以计算机软、硬件为基础,对DEM数据实现的一种三维立体可视化表达。本文从地貌晕渲的基本理论出发,以我国1∶100万标准分幅的西安幅(Ⅰ-49)为例,采用Global Mapper软件实现了计算机地貌晕渲自动制作的全过程,主要内容包括:计算机地貌晕渲关键技术的实现,地貌晕渲效果与参数设置之间的关系,Global Mapper软件中各种参数设置的合理性分析,使用分层设色的办法对晕渲图进行色彩的设计,并利用PHOTOSHOP软件对结果进行整饰等。该方法可实现地貌晕渲图的自动制图。

Based on mapping software such as Global Mapper,ERDAS and MicroDEM etc.,the relief shading maps can be automatically made by means of DEM data.In accordance with the basic theory of relief shading,taking Xi＇an region（sheet number Ⅰ-49,national standard division range 1∶1 000 000 geomorphologic maps） as an example,this paper presents the whole process of making relief shading using Global Mapper in computer.The key technology of relief shading is the main study content.The relationship between the effect of relief shading and the parameters is analyzed,and the rationality of various parameters setting in the Global Mapper is illustrated.The setting of light direction,environmental lighting and vertical exaggeration coefficient should perfectly represent not only the combination of the whole effect,but also the partial texture of the geomorphologic shading map.Therefore,the basic rules of relief shading map production and the geomorphology features of the study area before relief shading designing should be understood.In order to make colorful relief shading map,the elevation of the study area must be classified according to regional geomorphology features,and the color value of every levels is completed by hierarchical color design.Either evident regularity,or color and abundance of regional geomorphology were reflected in the relief shading map.Finally,the result maps need to be local fine adjusted in the PHOTOSHOP software.