此程序利用“弦高法”控制得到曲线上若干点，然后推广到三维曲面上布点，可以按照曲面曲率变化得到点的布局，最终三维图上显示出来-This procedure using the chord method control curve of some points, and then extended to 3D surface distribution, can be in accordance with the change of surface curvature point layout, the final three dimensional graph display