Displaying and reversing object direction
The direction of lines, polylines, 2D/3D polygons, and NURBS curves can be displayed and reversed, if desired, to help perform 3D operations and make end marker placement predictable.
To display the direction of an object:
Select one or more objects.
In the Object Info palette, select Show Direction. The object’s direction displays as a red arrow.
If desired, click Reverse Direction with one or more objects selected to reverse the direction of the objects. The arrow indicates the new direction.
The Show Direction option is not a property of any single selected object; it is a global state that indicates the direction of all selected objects until it is deselected.