摘要
针对现有点云索引研究方法欠考虑移动终端性能特点这一问题,提出了一种适用于移动端点云场景在线可视化的集成型空间索引。该索引首先利用考虑了移动终端网络带宽与计算渲染性能特点的改进型KD-tree实现点云数据的均衡划分与编码,在此基础上构建点云数据的LOD模型,并使用改进型八叉树管理其组织,最后通过改进型KD-tree的编码联结改进型八叉树形成〈1一级树:1二级树〉的优化型索引结构。该索引可支持移动端实现基于LOD的点云场景渲染策略,支持从数据块层面判断点云数据的空间关系,也支持数据的多线程查询。实验与分析表明:相比传统点云索引,该索引具有稳定的构建效率与优秀的空间查询性能,可为移动应用提供可靠的数据支持,能满足移动端点云在线可视化应用需求。
Current research on point clouds organization pays little attention to the performance characteristics of mobile devices.An integrated spatial index is proposed for online visualization of geo-scene point clouds on mobile devices.First,the index adopts an improved KD-tree which accounts for the network bandwidth and rendering performance of mobile terminal to implement a balanced division and coding of point clouds.Then,it builds a LOD model of point clouds and uses an improved Octree to organize the LOD models.Finally,the code of the improved KD-tree is concatenated with the improved Octree to form an optimized index structure of <1 level_1_tree:1 level_2_tree>.The proposed index supports LOD-based rendering,determination of spatial relations from data blocks and multi-threading data query.Experiments and analysis show that:compared to the traditional indexes of point clouds,this index has a stable construction efficiency and excellent performance of spatial query.It provides reliable data support for mobile applications and meets the diversified requirements of point clouds online visualization on mobile devices.
引文
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