正规网格等值线的虚路径扫描算法

Algorithm for Tracing Contour Lines Based on Virtual Paths

等值线图在工程分析和计算领域有着广泛的应用。该文以正规化的采样数据为研究对象，提出了一种全新的虚路径扫描算法。算法在数据网格基础之上构筑一虚拟的路径网格，利用路径网格上的线段（虚路径）来记录等值点的追踪路径信息。所有等值线的虚路径的捕获只需通过一次性扫描即可完成，不仅提高了追踪效率，而且避免了以往等值线追踪算法初始点选择困难、网格出口边判断复杂等一系列问题。算法的另一优点是追踪结果的精度是可控的，取决于等值点如何取值。该算法在土地定级中的作用分等值线图绘制中得到很好的应用。虚路径的思想同样适用于非正规的采样数据。

Contour map is widely used in engineering analysis and computing areas.Based on virtual paths which belong to paths mesh,a brand-new scanning method to tracing the contour lines is put forward,which make it Possible that all the information of contour lines can be collected completely just by scanning the source data mesh once.This method can not only greatly improves the computing efficiency,but also avoid many problems that always encountered by traditional algorithms such as the selection of the entry point of tracing of a contour line,the judgement of the exit edge of the mesh cell.The other strongpoint of the algorithm is that the computing precision can be controlled according to the specified application.The method has been applied to land classification and satisfied results are obtained,and the idea of virtual paths can also be applied for unnormalized source data.