Mouse Manipulation of Models

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 three-button mouse (although fewer buttons can be workable), models 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, depending on the mouse setup, an adjustment may be required.
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 increase the scale, whereas movements upward and/or to the left decrease it. Interactive scaling can also be performed by rolling a mouse's scroll wheel or by dragging the small square in the Side View.
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.

Also by default,

Ctrl-left mouse button performs picking (selection from the graphics window); the cursor will look like a pointing hand.
Placing the mouse cursor close to an atom or bond (without clicking any buttons) will cause the corresponding label information to appear. This atomspec balloon behavior can be turned off in the General preferences.

Mouse button assignments can be changed in the Mouse preferences.

Additionally holding down the Shift key reduces the speed (mouse sensitivity) of manipulations in the main window and Side View by a factor of 10.

Activation for Motion

A model must be active (activated for motion) to move in response to mouse manipulations or commands such as move and turn. Models are active by default, but it is necessary to toggle between activated and deactivated states to move one model relative to another. Model activation status can be controlled:

in the Model Panel
by toggling the checkboxes under the Command Line
with the command select

One- and Two-Button Mice

On a Mac with a one-button mouse, buttons 2 and 3 can be emulated with the option and apple (clover) keys, respectively. For example, click-dragging with the option key pressed performs XY-translation (assuming default Mouse preferences).

A two-button mouse is also workable. Starting with the default mappings, 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 or the command scale instead of with the mouse.

UCSF Computer Graphics Laboratory / October 2007