Multi-Resolution LOD Terrain Simplification Method Based on Multi-Factor Evaluation Criteria

With the continuous development of remote sensing technology, the amount of terrain related data has increased exponentially. However, current development of computer hardware cannot meet the demand for direct rendering of massive terrain dataset. Therefore, how to balance the responsiveness and quality of terrain rendering has become one of the critical research topic in large-scale terrain rendering. To improve the clipping and rendering efficiency of LOD terrain, this paper proposes a LOD terrain simplification method based on multi-factor evaluation indicators. Firstly, this method first designed a terrain node evaluation indicator which accounts for factors including viewpoint distance, surface roughness, viewpoint motion speed, and viewpoint rotation angular velocity comprehensively, to improve the visual effect of terrain node refinement operations and speedup rendering efficiency; Secondly, a terrain node visual clipping algorithm from coarse to fine was proposed, which uses terrain node bounding balls and visual volume bounding cylinders to quickly exclude distant terrain nodes before performing fine clipping, saving clipping time and improving the clipping efficiency of terrain nodes. Compared with traditional methods, the multi-resolution LOD terrain simplification method based on multi factor evaluation indicators proposed in this paper has achieved distinct improvements in both rendering efficiency and quality.