多尺度TIN管理及表达算法探讨  

Study on Management and Representation of Multi-Scale TIN

作　　者：王殷行[1] 石杏喜[2] 黄明丽[2] 

机构地区：[1]山东科技大学地球信息科学与工程学院,山东泰安271019 [2]南京理工大学材料科学与工程系,江苏南京210000

出　　处：《地理与地理信息科学》2006年第2期16-20,共5页Geography and Geo-Information Science

基　　金：国家自然科学基金项目"GIS多源集成空间数据间不一致性的智能化处理理论与方法"(40501053)

摘　　要：为实现大规模地形的多分辨率显示与实时绘制,基于LOD技术给出了多尺度TIN的管理和表达算法。探讨该算法相关的数据组织、LOD层次表达、实时刷新等关键问题。该算法使用分级策略,在不影响视觉效果前提下对TIN进行分级表达;使用分区策略,在可视化过程中对TIN进行局部更新。采取不同分辨率TIN模型间逐步过渡策略,基本上消除了视图变换时的跳跃感。实验结果表明,这种紧凑有效的TIN表示方法实现简单,内存开销较少,CPU耗费小,大大缩短了视图刷新切换时间,能够在普通机器上实现大规模地形的实时漫游。In order to improve the rendering speed of real - time display in large 3D landscape,this paper presents a LOD- based algorithm for management and representation of multi - scale TIN. The emphasis focuses on issues of transition among TIN models with different resolutions, and generation of these models, such as how to organize data and how to retrieve data in 3D visualization. For rende.ring and displaying terrain without losing visual scenes, a multi- level and multi - block expression algorithm of TIN is given in this paper. At last,the paper accomplishes simple implementation using a ease study of the ＂digital mine＂ system. Experimental results show that the algorithm has the advantages of the optimization of the triangle number, reduction of computation, and less utilization of extra memory etc. The algorithm can also support the real - time roaming for large- scale terrain in general desktop computers.

关 键 词：层次细节技术 多分辨率表达 分级表达 局部更新 多尺度TIN 

分 类 号：P208[天文地球—地图制图学与地理信息工程] TP391.9[天文地球—测绘科学与技术]