中文说明：三维刚性小球运动的DDA模拟程序,运用最简单的接触边界条件。运算是根据著名数学力学家石根华先生的非连续变形分析所以，可以模拟三维情况下的小球运动，可以在此之上加入边界条件，计算更复杂的案例
English Description：
Three-dimensional rigid ball DDA simulation program, using the most simple boundary conditions. Operation is according to Mr Shi Genhua, a famous mathematical mechanics of discontinuous deformation analysis, can simulate three dimensional case of ball games, where you can add boundary conditions, calculation of more complex cases