If this option is toggled on, the user can define the rotation center prior
to rotating the model. If the button is hit, eta/DYNAFORM prints the
following message in the message prompt window:
PICK A
LOCATION AS ROTATION CENTER
The user can click anywhere in display window as the rotation center. Then,
holding the left mouse button down, move the mouse cursor to rotate the model
around the defined center.
If the
rotation shortcut key (<CTRL> + left mouse button) is used to rotate the
model, the immediate location upon which the mouse cursor is placed is automatically
defined as the rotate center. The model is rotated around the center.