Each bounding box can be defined as having an X-, Y-, and Z-axis. The plane of the bounding box contains the Y- and Z-axis, while the X-axis is normal to the plane. The following illustration shows a standard bounding box, in which the blue arrows represent the Y-axis, and the green arrows represent the Z-axis.
Based on the right-handed coordinate system, the X-axis is normal to the plane and pointing out of the page towards you.
By changing the orientation of the Y and Z vectors, you have complete control over the bounding box. You can rotate the Y and Z vectors by some angle, effectively rotating the bounding box as shown in the following illustration. This provides an easy mechanism for rotating supports that attach to multiple supported objects.