This will create handles that can be used to control the size and shape of the curve at that point.
这将创建手柄，用来控制那个点的曲线的尺寸和形状。
2
To do this, the monotone curve is firstly drawn, and then without finding the coordinate of the inflexion point, the NC machining path can be obtained by the method of automatic direction control.
首先对单调NC轨迹曲线进行绘制，进一步用不求极值点坐标而实现自动控制变向的方法，求出NC加工轨迹；
3
A quadratic bezier curve has a start and an end point (blue dots) and just one controlpoint (red dot) while a cubic bezier curve USES two control points.