多分辨率GIS矢量数据模型构建与三维显示方法研究

本文提出一种GIS矢量数据多分辨率模型的构建、组织及三维显示方法。在数据预处理阶段，首先对原始矢量数据（点、线、面）进行简化处理，抽取出若干不同分辨率的矢量层次，然后将各个矢量层次分块，自底向上建立矢量数据的四叉树结构。在实时绘制阶段，在基于四叉树的视锥裁减和基于屏幕误差度量的分块选取基础上，采用多态调度矢量数据分块。实验结果表明，本文提出的矢量数据组织和调度算法能较好地解决矢量数据量大与计算机实时处理能力有限的矛盾，满足大规模矢量数据三维可视化系统实时绘制需求。

Research on the Multi-Resolution Modeling and Three-Dimensional Display of GIS Vector Data

This paper proposes a method for multi-resolution modeling,organization and three-dimensional display of GIS vector (points,lines,polygons) data.In the preprocessing phase,the multiple representation of vector data is extracted by vector simplification algorithms,then each representation layer is partitioned into small blocks which are used to construct the hierarchical vector data quad-tree in a bottom-up way.At run-time a synchronous thread is employed to schedule vector data blocks specified by the view-frustum culling results and screen space error metrics.Experimental results show that the proposed approaches can satisfy the requirements of real-time rendering of large-scale vector data,which benefit from the multi-resolution data organization and data scheduling scheme.