Rotate
Description
The selected part of a structure can be rotated by dragging it while
in rotation mode. Rotation mode can be turned on and off from the "Mode"
menu (usually key-shortcut r) or with the rotate button.
The center of rotation is indicated by a target,
which can be repositioned with the mouse.
The current helix (the one which has the current item) can also be oriented
in a given direction using the "Geometry toolbar" or
"Orient" options in the "Geometry" menu. The selection will be rotated
together with the current helix.