该程序是Cassini椭圆函数的等高线曲线，再VC++MFC环境下用OpenGL绘制，本程序采用的方法是利用插值法求得等高曲线和单元边线的交点，函数在50*50的单元栅格上采样。,The program is Cassini cnoidal contour curves, and then VC++ MFC with OpenGL rendering environment, the procedure adopted is to use obtained by interpolation co