摘要
3DGIS仅用数字高程模型(DEM)表现地形远达不到三维可视化的要求。在传统3DGIS中,通常采用数字正射影像(DOM)作为DEM的纹理表达地面景观,但其逼真性往往会受到影像分辨率的限制。该文借鉴Mipmap思想,提出一种新的纹理生成方法来解决上述问题,即通过对DOM和二维矢量数据赋予投影信息,将多幅影像及相关矢量数据作为生成3DGIS地形的纹理数据源,生成不同分辨率、不同详细程度的金字塔纹理,动态表现地面景观,并对生成的金字塔模型数据进行高效的索引、存储与管理。上述方法在实际应用中取得了满意的访问效率和视觉效果。
Digital Orthophoto Maps（DOM） are traditionally used for terrain texture rendering to simulate realistic landscape in 3DGIS,however the effect of visualization is significantly affected by the resolution of images.In this paper,a new approach that combined multi-resolution DOM with multi-scale 2D vector dataset under same projection was presented to generate high quality composite terrain textures.The texture database is organized as a dual-level indexed pyramid model,in which the level of detail varies among texture plates and all tiles on the same plate are mashed seamlessly each other.This algorithm was successfully demonstrated in a 3D city planning application.
出处
《地理与地理信息科学》
CSCD
北大核心
2009年第2期15-18,共4页
Geography and Geo-Information Science
基金
国家863计划项目(2007AA12Z210)
