B样条曲线的等距算法及应用

Offset Algorithm and Its Applications of B-Spline Curves

等距曲线的拓扑结构是等距算法中的核心因素之一。该文以B样条曲线为例,给出了一种基于关键点的等距算法。它应用了自适应离散等手段并给出了关键点的求解方法,同时利用关键点确定等距线各个分段的取舍,从而有效地去除自交的情况,使得计算出的等距曲线有着正确的拓扑结构。该文的算法已应用于商业软件OpenCAD中。

The proper topology structure is a key factor of the offset algorithm of a curve.An offset algorithm of B-spline curves is presented based on the key points on the offset curve.Firstly,the key points are computed by using self-adaptive sampling technique,then the self-intersected segments are discarded,and the proper topology structure is ensured.The algorithm has been applied in the business software OpenCAD.