中文摘要：

提出了一种高效的磁盘、内存、显存三级数据存储粒度与结构一致的数据组织方法。首先,根据城市空间对象数据内容,建立层次嵌套、多类型混合的空间索引结构,以空间索引节点统一磁盘存储、内存场景管理与绘制缓存的基本操作单元;其次,以绘制缓存对象的紧凑存储结构为基础,统一内存场景管理对象与磁盘存储对象的数据块结构,并将数据布局方法扩展到对象粒度进行磁盘存储组织。实验结果表明,所提方法大幅度减少了I/O次数,提高了数据调度效率,为大规模三维城市模型的实时绘制奠定了基础。

英文摘要：

The data granularity and structure difference among the disk storage objects,memory management objects and rendering cache objects results to heavy counts of disk I/Os.This becomes one of the reasons causing data access delay.We propose a data organization method to uniform the granularity and structure in disk,memory and display cache.Firstly,we use the spatial index node from a hierarchical-nested and hybrid spatial index to uniform the disk storage,memory management and rendering cache basic operation unit.Secondly,the data structure is formated in disk and memory based on the structure of rendering cache objects.And the data layout method is extended to the object level using in disk storage to reduce the data format convention and disk I/O seeking time.Tests prove the obvious reduction of I/Os in the real-time rendering of large-scale 3D city models.