By default, a surface's axis is at the centre of the surface. Use the Off X and Off Y fields to offset a surface along the X-axis or Y-axis. All rotations, scaling, and shearing applied to a surface are applied about its axis. The location of the axis is indicated by the axis icon in the scene. See Accessing the Axis Menu.

To offset a surface:

1. Select the surface you want to offset.
2. In the Surface menu, change the Off X and Off Y fields accordingly.

   
   

   (a) Surface Offset fields  

   The following figure illustrates the difference between rotating a surface that has not been offset and a surface offset using the Off X field.

   Rotated image with no offset. Notice that the axis is in the centre of the image.

   Rotated image with an offset along the X-axis. Notice that the axis is offset from the image centre.