基于SuperMap的全球晕渲图设计与制作

晕渲图的设计与制作一直是地学工作者研究的热点问题,使用晕渲图展示地形直观、形象、立体感强.目前有多种思路被提出用于改善晕渲图的显示效果,但是在制作小比例尺晕渲图时,仍然存在一些问题,如地形破碎导致难以把握地形宏观骨架,缺少海洋地形或海洋地形过于具体干扰到陆地要素表达,传统的DEM与山影数据叠加的模式使得美观与地形清晰无法兼得,这就需要重新对这些问题进行思考.本文以晕渲图的基本理论为出发点,采用地貌晕渲与分层设色相结合的方法,讨论全球范围的晕渲图制作过程中,不同显示比例尺下DEM分辨率配置技巧、海洋地形展示方法与地形可视化新思路.实验证明,该方法可以保证晕渲图在每级显示比例尺下都能展示出良好的地形效果,为中小比例尺晕渲图增强表现力提供了参考.

Design and Creation of World Relief Map Based on SuperMap

Methods for design and creation of relief maps have always been the research issues in geosciences, since relief maps pro-vide visualized, intuitive, and pronounced three-dimensional sense for users. There are some disadvantages in creating small-scale relief maps using existing methods, which includes macro skeleton of the terrain is obscured because of fragmentized terrain being used to create relief map, and the expression of land elements is interfered due to the lack of marine terrain or marine terrain being too spe-cific, and compromise of beauty and clarity caused by traditional overlay mode of DEM and hillshade. It is therefore necessary to re-think new method to solve these issues. Based on the basic theory of relief maps, we combine the shaded relief with hypsometric layers to improve the terrain visualization. Technical details of creating global relief maps using DEM data in different resolutions, displaying marine terrain in a proper way, and visualizing terrain data in new perspectives are illustrated. Experiments show that our method guarantees the display effect of relief maps in all scales, making relief maps in middle and small scales more expressive.