Moving cursor away causes shapes to rotate.
To move shapes click and drag to the desired position.

Press "LEFT"  to change the color of the last selected node.

Double click to change shape.

Press "RIGHT" to add a child to the node.
(Note: pressing 'right' twice will create another child on the top of the previous one, so that we can drag the nodes to desired place after creation)

Press "UP" & "DOWN" to change the size.

Type "make run" to compile & run.