两种面向地貌晕渲的光照模型比较  

Comparision of Two Relief Shading Oriented Illumination Models

作　　者：张威巍[1] 游雄[1] 宋国民[1] 

机构地区：[1]信息工程大学测绘学院,河南郑州450052

出　　处：《测绘科学技术学报》2009年第2期153-156,共4页Journal of Geomatics Science and Technology

摘　　要：光照模型是影响数字地貌晕渲的一个关键因素。在参照传统晕渲着色规则的基础上,结合数字地貌晕渲的投影方式及视点、光源的设置方法,从理论上分析了Lambert漫反射模型、基于坡向光照模型的特征;分别利用规则物体和地形数据对这两种光照模型所产生的效果进行了实验和对比;结果表明漫反射模型更适合起伏较平缓地区的晕渲,基于坡向的光照模型更能突出山体的起伏特征。最后结合理论分析讨论了产生这种实验结果的原因并提出了3点改进意见。Illumination model is one of important factors which impact digital relief shading. Refering to traditional relief shading rule, the characters of Lambert diffuse illumination model and aspect-based shading was analyzed based on the method of projection, view and lighting in digital relief shading. The relief shading outcomes of two illumination models were compared using regular object models and DEM. The experimented results showed that Lambert diffuse model was more suitable for representing flat terrein and aspect-based shading was more suitable for rendering fluctuant terrein. At last the reason of the experimented results abstractly was discussed and three improving ideas were brought forward.

关 键 词：数字地貌晕渲 Lambert漫反射模型 基于坡向的光照模型 

分 类 号：P208[天文地球—地图制图学与地理信息工程]