The Surface Rotator Utility is used to rotate the surface around it's center point location.  There are options to rotate the surface data 90 degrees in the clockwise (CW) direction, 90 degrees in the counter-clockwise (CCW) direction, 180 degrees, or any user-specified angle.  Linear interpolation is used to compute the new surface data height information.  The areas in the corner of the data set that does not contain surface data will become "non-measured" samples.