一种视觉变量相似性驱动的点数据符号化过程模型

首先分析了点数据符号化过程中的视觉变量相似性和绘制流程可重用性.在此基础上提出一种视觉变量相似性驱动的符号化过程模型.该模型将顺序型的地图符号化流程改变为符号化子过程可交叉共享的符号化流程.针对I/O密集的符号图形构造过程,提出图形缓存;针对计算密集的符号图形离散过程,提出扫描线缓存;针对像素操作密集的符号栅格化过程,提出栅格缓存.试验结果表明本文方法能够在保证绘制质量的前提下显著提高点数据的符号化效率.

A Visual Variable Similarity-driven Symbolization ProcessModel for Point Datasets

The visual variable similarity and drawing process reusability was analyzed in the process of point data symbolization. Then, a symbolic process model driven by visual variable similarity was proposed. Compared with the sequential symbolization process, the subprocess of symbolization could be shared in this model. For I/O-intensive symbol graphical construction process, graphic cache was proposed. For compute-intensive symbol graphical discretization process, scan line cache was proposed. For pixel-operation-intensive symbol rasterization process, raster cache was proposed. Under the precondition that drawing quality is ensured, the experimental results show that the method presented can significantly improve the symbolic efficiency for point datasets.