BsplineCurve

代码说明：

  实现通过用户给定B样条曲线的控制顶点、设定B样条曲线的次数及类型，进而绘制出相应的B样条曲线和对应的基函数图形。并且可以通过鼠标拖拽控制顶点修改B样条曲线和对应的基函数图形。从而，对B样条曲线和基函数的性质有更深入更直观的了解，理解B样条曲线和基函数的对应关系，在以后的学习中能更好地运用B样条曲线。(The number and type of user to achieve a given control vertices B-spline curve, set the B-spline curves, and then draw the corresponding B-spline basis functions and the corresponding graphic. And can be modified by dragging the mouse to control the apex B-spline curves and the corresponding basis function graphics. Thus, the nature of the B-spline curves and basis functions have a deeper and more intuitive understanding, understanding of the correspondence between the B-spline curves and basis functions in later learning to better use of B-spline curves.)