The autoplace plugin looks at the netlist and tries to place subcircuits in a way to get routing easier. The algorithms follow those described in sections 4.1 of "Placement and Routing of Electronic Modules" edited by Michael Pecht Marcel Dekker, Inc. 1993. ISBN: 0-8247-8916-4 TK7868.P7.P57 1993.
The plugin declares action AutoPlaceSelected which operates on the selected subcircuits. A netlist shall be loaded and subcircuits available on the board before the action is invoked.