<1>平移矩阵
1点平移(点平移位置会改变)
1*x+0*y+0*z+tx*1 = x+tx
0*x+1*y+0*z+ty*1 = y+ty
0*x+0*y+1*z+tz*1 = z+tz
0*x+0*y+0*z+1*1 = 1
点的4个分量为: (x+tx , y+ty , z+tz , 1)
2 向量平移(向量没有位置属性)
<2>缩放矩阵
1 点缩放
kx*x+0*y+0*z+0*1 = kx*x
0*x+ky*y+0*z+0*1 = ky*y
0*x+0*y+kz*z+0*1 = kz*z
0*x+0*y+0*z+1*1 = 1
<3>旋转矩阵(3个轴)
1 X轴旋转
2 Y轴旋转
3 Z轴旋转
