Screen-space adaptive tessellation for terrain rendering
屏幕空间自适应的地形Tessellation绘制

In order to render large-scale terrain on graphics processing units (GPU)using hardware-accelerated tessellation, a screen-space adaptive tessellation algorithm for terrain rendering is presented. The triangulation is performed entirely on the GPU, based on analyzing the principle of terrain tessellation. The proposed approach organizes the terrain data hierarchically by tiles and patches, which is the base for a terrain LOD simplification approach processed separately on the CPU and GPU. The edge-based tessellation LOD model for each patch is constructed to compute the tessellation factors in the Hull Shader for the water tightness surface. The procedure for terrain displacement mapping in the Domain Shader is designed to offset and transform each vertex height. Furthermore, a two-level view frustum culling mechanism is used to minimize the data to be rendered. The experimental results show that the algorithm has better screen-space adaptivity and rendering performance. It can produce the terrain model with high resolution geometric details in spite of inputting coarse triangle meshes.