Abstract: This paper will present an easy-to-implement algorithm for rendering terrain on GPU.By moving the height field lookup and aggregated LOD handle from the CPU to the GPU，the vertex positions can be calculated in the vertex shader which are combined with hierarchical index template.Then，only one API calls for all triangles by using a suitable primitive to index terrain vertices.Finally，the extra vertices are simply added at the end of the buffer to fill the cracks which may occur.Those“skirt vertices”can be able to represent all indices as some triangle_lists.Thus，it is no longer necessary to perform per frame vertex buffer updates.The presented algorithm reduces the system memory and CPU requirements.

Key words: vertex shader, aggregated Levels Of Detail（LOD）, hierarchical index template, vertex skirt

摘要： 提出了通过GPU渲染地形的一种简易方法，首要的任务就是将高度场的查询及批LOD处理也从CPU移至GPU。顶点位置可结合层级索引模板由顶点着色器计算给出，然后，对地形顶点采用适当的图元进行索引，调用一次API就可绘制所有的三角形。最后，添加额外的“裙摆顶点”来填补由批LOD算法造成的裂缝。该算法不必每帧都更新顶点缓冲，从而大大减少了系统内存和CPU的开销。

关键词: 顶点着色器, 批层次细节, 层级索引模板, 顶点裙摆