Draws an arrow, using four points: the head and two tail points, and a
foldback point, which permits the tail of the arrow to be indented.
Width of the tail of the arrow
Distance from the tail of the arrow to the head
Where, either as a proportional value from 0 to 1 inclusive, or as an absolute value (negative values mean distance from target; positive values greater than 1 mean distance from source) the Arrow should appear on the Connector
Which way to point. Allowed values are 1 (the default, meaning forwards) and -1, meaning backwards
How far along the axis of the arrow the tail points foldback in to.
A style object in the form used for paintStyle values for Endpoints and Connectors.