基于外存的大规模虚拟环境交互漫游

Interactive Out-of-core Walkthrough of Large-scale Virtual Environments

针对大规模虚拟环境的交互漫游,提出了一种基于外存的场景数据组织方法,并给出了相应的交互漫游算法。首先将场景数据分块组织成八叉树层次结构,然后为每个八叉树节点生成渐进网格表示。在实时绘制阶段,利用八叉树层次进行粗的全局细化,利用渐进网格进行细的局部细化。该方法可以对具有上千万三角形面片的大规模虚拟环境进行交互绘制,并且可以得到连续的LOD变化,消除交互漫游时的“Popping”(跳跃)现象。

An out-of-core organization approach for large-scale virtual environments was proposed, and also an interactive corresponding walkthrough algorithm was given. A spatial octree partition was used to build a hierarchical decomposition of the scene and then the progressive mesh for each octree node was computed. At run time, the octree hierarchy was used for coarse global refinement, and the progressive meshes was used for fine local refinement. The approach can render large-scale virtual environments of hundreds of millions of triangles at interactive rates with continuous level of detail transitions and minimal popping artifacts.