The key technology is LOD algorithm. I use the view-dependent and terrain's roughness to determine the terrain detail. Before render the terrain.

本文的关键是LOD算法，我使用了视点相关以及和地形本身起伏程度相关的技术来决定地形应有的细节程度。

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This paper proposes a dynamic simplification algorithm for the terrain model based on the Triangle Subdivision Bi tree to realize continuous view dependent multi resolution rendering of terrain mesh.

为实现地形漫游，提出基于三角形二叉树的地形网格模型动态简化算法，实现了与视点相关的连续多分辨率简化及快速动态绘制。

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ROAM method adopts split and merge operations to adjust triangle meshes, can interactively perform view-dependent, locally-adaptive terrain meshing and can construct multiresolution terrain model.

ROAM算法就是通过采用分解和合并方法实时地调整三角形网格，能交互式地实现观察依赖、局部可调整的地形网格化处理，生成多分辨率的地形模型。

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