三维地形可视化中不同图元渲染效率比较分析  

Comparative Analysis for Different Primitive Rendering Efficiency in Three-Dimensional Terrain Visualization

作　　者：何望君[1] 牛艺博 刘纪平[1] 张福浩[1] 

机构地区：[1]中国测绘科学研究院,北京100830 [2]兰州交通大学测绘与地理信息学院,甘肃兰州730070

出　　处：《测绘与空间地理信息》2014年第11期53-56,共4页Geomatics & Spatial Information Technology

基　　金：国家863课题(2012AA121202)资助

摘　　要：大规模地形场景一般由几百万甚至更多的顶点构成,地形瓦片的图元组织与绘制效率直接决定了地形渲染的速度和质量。为明确Triangles,Triangle Strip,Triangle Fan和优化的Triangle Strip图元渲染效率,选取常用的11种大小瓦片样本进行对比试验。从初始化时间、索引缓存大小和实时绘制时间3个方面评估图元效率。结果表明:在地形瓦片小于256时,Triangles和优化的Triangle Strip具备较高的渲染效率,Triangles会占用较大的索引缓存;在地形瓦片超过256时,优化后的Triangle Strip图元具有最高绘制效率,并且占用最小的索引缓存。Large-scale terrain scene is generally composed of several million or more vertices , primitive organization and efficiency of drawing triangles directly determine the speed and quality of the terrain rendering .With the terrain tiles samples of eleven different si-zes, a comparison experiment is carried out to confirm rendering efficiency of Triangles 、Triangle Strip、Triangle Fan and Optimizing Triangle Strip.An evaluation about primitive efficiency is also made with initialization time , index cache size and rendering time .The results showed that：Triangles and optimized Triangle Strip have high rendering efficiency when the terrain tile is less than 256 , mean-while Triangles will occupy a larger size index cache .Optimized Triangle Strip primitive mode has the highest efficiency of drawing and minimal size index cache when the terrain tiles over 256 .

关 键 词：三维地形可视化 图元 TRIANGLE STRIP 索引组织 批量绘制 

分 类 号：P217[天文地球—测绘科学与技术]