目的 目前全球大规模地形可视化问题基本都衍生于分块LOD(level of detail)方法,该方法在快速地表漫游中依然存在GPU-CPU的数据传输瓶颈,其基于裙边的缝隙修复方法既需要额外资源,还存在依然无法完全消除的痕迹。为解决这些问题,提出了一种GPU网格生成的地形可视化方法。方法 结合GPU Tessellation方法、基于视点与屏幕空间误差的LOD方法、局部坐标系渲染等算法,使得全球地形可视化的生成效率有明显提高。结果 实现了一个全球地形可视化系统GTVS,提供全球高精度地形数据与多分辨率高清卫星影像数据的调度与渲染等。论文对该系统进行了详实的实验和数据分析,相比传统基于GPU的分块LOD方法,FPS(frames per second)提升100%以上,很好地解决了系统瓶颈问题。结论 结果表明所提方法实用、鲁棒、扩展性好,可广泛地适用于大规模的全球渲染系统中。

Objective Existing methods for visualizing global-scale terrains are basically derived from the chunked LOD method. With such methods, GPU-CPU data transfer bottlenecks still emerge in real-time walkthroughs. Moreover, the addition of skirts to fix cracks requires additional resources and may not even eliminate artifacts completely.To address these issues, we proposed a GPU terrain visualization method that combines the GPU tessellation algorithm. Method The view-dependent and screen space error-controlled LOD method, and local coordinate system rendering algorithms. This method significantly improved the efficiency of global terrain visualization. Result A global terrain visualization system was implemented to provide global multi-resolution satellite images and achieve high-resolution terrain field data rendering. Extensive experiments were performed to analyze the system benchmark. Compared with the traditional GPU-based chunked LOD method, the proposed method can improve FPS by more than 100%, thus eliminating the system bottleneck problem. Conclusion The proposed method is practicable, robust, and widely applicable in large-scale global rendering systems.