基于自适应四叉树的地形LOD算法

New LOD method based on adaptive quad-tree for terrain visualization

大数据动态地形三维可视化需要使用分层细节技术(LOD)简化模型,提高三维可视化效率,而四叉树可以优化复杂数据的数据结构。首先讨论了基于自适应四叉树实现LOD的一般方法,详细探讨了模型连接的三角扇绘制法;然后针对四叉树结构多分辨率表示的特点,提出了一种基于自适应四叉树节点属性修改,实现LOD模型的连续无缝连接的方法;最后使用提出的方法,实现了一幅1∶50000地形图范围的三维可视化,有效提高了动态显示效果。

Level of Detail （LOD） is utilized to simplify the model as well as to improve the efficiency in 3D visualization of terrain with large data. The quad-tree is a kind of data structure that is able to optimize complicated data. First, the authors discussed the general method of LOD based on adaptive＇ quad-tree and described the triangle-fan method for model drawing; second, according to the features of multi-resolution of the quad-tree, a method for seamless model drawing, based on the attribute revision of the node in the quad-tree, was proposed; finally, the 3D visualization of a 1：50000 map was achieved by this method and the dynamic display was improved.