Mouse Manipulation of Structures

The X axis is horizontal in the plane of the screen, the Y axis is vertical in the plane of the screen, and the Z axis is perpendicular to the plane of the screen. By default, using a 3-button mouse (see below if dealing with a 2-button mouse), structures are:

• rotated with the left mouse button in the graphics window. Rotation is about the X and/or Y axis when the cursor is in the central region of the graphics window (the cursor becomes a small circle) and about the Z axis when the cursor is in the periphery of the graphics window (the cursor becomes two curved arrows in yin-yang configuration). The center of rotation can be adjusted with the Rotation tool or the command cofr.
  
  
• XY-translated with the middle mouse button (the cursor will look like a cross formed by two double-headed arrows). On Windows systems, depending on the mouse setup, an adjustment may be required.
  
  
• Z-translated with Ctrl-middle mouse button (the cursor will look like a vertical double-headed arrow); movements downward and/or to the right translate structures closer, and movements upward and/or to the left translate structures farther away. Note that Z-translation is not the same as scaling (below).
  
  
• scaled with the right mouse button (the cursor will look like a diagonal double-headed arrow enclosing a small square); movements downward and/or to the right enlarge structures (increase the scale), and movements upward and/or to the left shrink them (decrease the scale). Scaling can also be performed using the mouse within the Side View, or by entering a specific scale factor with the scale command in the Command Line.

Selection of atoms and bonds from the graphics window is also called picking. During picking (by default, Ctrl-left mouse button), the cursor looks like a pointing hand.

Models that have been deactivated for motion cannot be translated or rotated with the mouse or commands.

The mouse button assignments can be changed in the Mouse preferences.

Note that holding the Shift key down will reduce the speed (mouse sensitivity) of manipulations in the main window and Side View by a factor of 10.

Finally, if Show atomspec balloon is set to true in the General preferences, placing the cursor close to an atom or bond will cause the corresponding label information to appear and remain until the cursor is moved away.

While it is best to have a three-button mouse, a two-button mouse is workable. If the right button of a two-button mouse is not already performing XY translation, use the Mouse preferences to reassign XY translation to button 3. The right button of a two-button mouse should then work for XY translation, leaving the left button for rotation (the default). Scaling can be performed with the Side View and the command scale.