根据向量运算，实现了球体与线段，球体间的碰撞检测，可根据需要加入引力参数。同时在j2me平台测试了球体碰撞，当然GUI可根据需要定制。-According to vector operations, to achieve a sphere with the line, the ball collision detection between, according to the need to add gravity parameters. Also tested in the j2me plat