3D图形计算，旋转指以立体三角的顶点为中心,底座旋转.深度指距离,越大离你越近,0是3D空间中心点,负数指中心点之后，有三维空间的立体感。作者注：旋转代码有重大缺陷请勿深入学习以免影响将来正式学习!这篇代码建议随便看看就好-3D graphics computing rotation refers to the three-dimensional triangle vertices as the center, the base is rotated. Depth refers to the d