基于块段模型的三维GIS混合数据结构模型研究

Study on 3D GIS hybrid data structure based on block model

为了有效地表示三维GIS空间实体,在地质块段模型的基础上,提出了基于八叉树和四面体格网的混合数据结构模型(block octree tetrahedron,BOT模型)。采用BOT模型生成算法对块段模型进行重新分割,八叉树作整体描述,四面体格网作局部精确描述,并以不同的灰度值表示不同的单元块属性。同时,为节省存储空间,提出了线性BOT编码技术。实验结果表明,BOT模型充分发挥了八叉树和四面体格网的优点,可以在不增加存储空间的前提下实现对三维目标更高效、更精确的表达。

In order to represent 3D GIS spatial entity effectively, a hybrid data structure model called BOT model（ block octree tetrahedron model） was presented on basis of geological block model, which combined octree and tetrahedral network （TEN） structures. Using BOT generation algorithm, the block model was redivided with octree as general shape description and TEN as partial precise description, in which different gradation of grey were used to stand for different attributes of unit blocks. To reduce the memory space a linear BOT coding technology was proposed as well. The results of simulation experiments made with empirical data demonstrate that the BOT model holds merits of both octree and TEN and can represent 3D objects more effectively and precisely.