等值线填充就是先在等值线间建立拓扑关系，然后基于拓扑关系来完成等值线的填充，这一直是一个比较困难的问题。为了快速方便地进行等值线自动填充，提出了一种基于不规则三角网的等值线自动填充算法。该算法把采用不规则三角网生成的非闭合等值线，先根据一定关系与自定义边界连接成闭合等值线，然后通过确定各闭合等值线之间的包含关系和各等值线之间的填充颜色来绘制出等值线填充图。实践表明，该算法易于实现，且运算速度能满足业务需求。

Contour filling is based on the topology relationship between contours，which remains a difficult research question.In order to fill contours fast and conveniently，a new automatic filling algorithm between contours based on triangulation irregular net was proposed.From the relationship between unclosed counters generated by the irregular triangulation net and the custom border，the closed counters were built，and then the filling color between contours was determined through determining the relationship of the closed counters，so the contour filling chart was mapped.This algorithm is easy to implement and the computing speed can meet the business needs.