Picking Mode
MouseWheel	scale
CTRL + MouseButtonOne on node	node will be placed in the middle of display
MouseButtonOne click on node/edge	select a node/edge
MouseButtonOne on node + drag	move selected node
MouseButtonOne + drag	select multiple nodes
MouseButtonOne on one of the selected nodes + drag	move all selected nodes
Transforming Mode
MouseWheel	scale
CTRL + MouseButtonOne + drag	asymmetric skew
SHIFT + MouseButtonOne + rotate(drag)	rotate the display