说明：  1.编写一段代码，绘制一个球体，然后平移（利用hold on把变换前后的球体放在同一个figure中） 2. 编写一段代码，绘制一个柱体，然后绕x轴旋转60° 3. 用sphere生成多面体，然后对其进行错切变换 4.程序先绘制一个长方体，然后隔0.1秒又绘制出另一个围绕z轴旋转i角度的长方体， 循环中每次（每个顶点）都被旋转矩阵变换成新的顶点。把变换矩阵改成围绕x轴的旋转矩阵、y轴旋转的 变换矩阵， 5. 透视投影和平行投影
(1. Write a piece of code, draw a sphere, and then translate (use hold on to put the sphere before and after the transformation in the same figure). 2. Write a piece of code, draw a cylinder, and then rotate 60 around the X axis. 3. Use sphere to generate polyhedron, and then transform it by crosscutting 4. The program first draws a box, and then draws another box with an angle of rotation I around the Z axis every 0.1 seconds. Each time (each vertex) in the cycle is transformed into a new vertex by the rotation matrix. Change the transformation matrix to the rotation matrix around the x-axis and the rotation matrix around the y-axis 5. Perspective projection and parallel projection)