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 .%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。
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