基于菱形块四叉树的全球六边形网格实时绘制方法

摘要

Considering the complex coding and difficult layering of global hexagon grid, a real-time rendering method for global multi-resolution hexagon discrete grid based on quad-tree of diamond blocks was proposed. Firstly, the regular icosahedron was served as subdivision basis and divided the world into ten basic diamond blocks, which were treated as root nodes of quad-tree; after that, a simplified hexagon coding algorithm was in-troduced to realize the fast index of hexagons and diamond blocks between hierarchies and build the quad-tree model for diamond hexagon blocks by means of hexagon subdivision with the aperture of 4; finally, to solve the crack problem in the diamond block triangulation process, four kinds of triangle strip were designed to achieve real time mending of cracks in the scheduling process. The experimental results show that this method can realize the viewpoint related visualization of global discrete grid with multi-resolution in the situation that the grid topo-logical structure is almost invariant. Compared with the same precision single resolution grid, the method can speed up the rendering efficiency and effectively reduce memory usage rate at the same time.%为解决全球六边形网格编码复杂、不易分层的问题提出一种基于菱形块四叉树的全球多分辨率六边形离散网格实时绘制方法.首先以正20面体作为剖分基础将全球划分为10个基础菱形块并使之作为四叉树根节点;然后引入一种简化的六边形编码算法借助孔径为4的六边形剖分方式实现层次间六边形与菱形块的快速索引建立菱形六边形块的四叉树模型;最后针对菱形块三角化过程产生的裂缝问题设计4类三角形条带在调度过程对裂缝进行实时缝补.实验结果表明该方法可在网格拓扑结构基本不变的情况下实现视点相关的全球离散网格多分辨率可视化与相同精度的单分辨率网格相比在加快渲染效率的同时能有效地降低内存占用率.