How Gizmos Are Used

There are three types of gizmos:

• 3D Move gizmo. Relocates selected objects along an axis or plane.
• 3D Rotate gizmo. Rotates selected objects about a specified axis.
• 3D Scale gizmo. Scales selected objects along a specified plane or axis, or uniformly along all 3
  axes.

By default, gizmos are displayed automatically when you select an object or subobject
in a view that has a 3D visual style. Because they constrain modifications along specific
planes or axes, gizmos help ensure more predictable results.

You can specify which gizmos are displayed when an object is selected, or you can
suppress their display.

Display the Gizmos

Gizmos are available only in 3D views that are set to use a 3D visual style such
as Hidden. You can set the gizmo to be displayed automatically when you select a 3D
object or subobject. Gizmos are also displayed during the 3D Move, 3D Rotate, and
3D Scale operations.

By default, the gizmo is initially placed in the center of the selection set. However,
you can relocate it anywhere in 3D space. The center box (or base grip) of the gizmo
sets the base point for the modification. This behavior is equivalent to temporarily
changing the position of the UCS as you move or rotate the selected objects. The axis
handles on the gizmo constrain the movement or rotation to an axis or plane.

Switch Between the Gizmos

Whenever you select an object in a 3D view, the default gizmo is displayed. You can
select a different default on the ribbon, or change the value of the DEFAULTGIZMO
system variable. You can also suppress the display of gizmos when objects are selected.

After the gizmo is active, you can also switch to a different type of gizmo. The switching
behavior differs, depending on when you select the objects:

• Select objects first. If a gizmo operation is in progress, you can press the Spacebar repeatedly to cycle
  through the other gizmo types. When you switch gizmos this way, the gizmo activity
  is constrained to the originally selected axis or plane.

  During a gizmo operation, you can also select a different gizmo type on the shortcut
  menu.

• Run the command first. When you start the 3D Move, 3D Rotate, or 3D Scale operation before selecting objects,
  the gizmo is placed at the center of the selection set. Use the Relocate Gizmo option
  on the shortcut menu to relocate the gizmo anywhere in 3D space.You can also choose
  a different type of gizmo on the shortcut menu.

Change the Gizmo Settings

The following settings affect the display of gizmos:

• Default gizmo. The DEFAULTGIZMO system variable specifies which gizmo is displayed by default when
  an object is selected in a view with a 3D visual style. You can turn off display of
  the gizmo. This setting is also available on the ribbon.
• Default location. The GTLOCATION system variable sets the default location of the gizmo. The gizmo
  can be displayed at the center of the selection set (default), or it can be positioned
  at the 0,0,0 coordinates of the current UCS.
• Automatic display. The GTAUTO system variable sets whether gizmos are displayed automatically whenever
  you select objects in a 3D view that is set to a 3D visual style (default). If you
  turn off this system variable, the grips are not displayed until the gizmos are active.

• Conversion of move, rotate, and scale operations from 2D to 3D. Turn on the GTDEFAULT system variable to start the 3DMOVE, 3DROTATE, or 3DSCALE command
  automatically when the MOVE, ROTATE, or SCALE command is started in a 3D view. This
  system variable is turned off by default.
• Active status of subobject grips. If you select a subobject, the GRIPSUBOBJMODE system variable sets whether the subobject
  grips are active immediately. Setting subobject grips to be active upon selection
  helps you modify groups of mesh subobjects without selecting them again.