Continuity at the junction between successive cubic bezier splines is enforced.
'Q' turns the control polygon off / 'W' turns the control polygon on
'E' turns the control points off / 'R' turns the control points on
'I' increases the point sizes / 'O' decreases the point sizes
'N' increases permissiveness of clicking a point / 'O' decreases (within how many pixels must you be)
'J' increases the fine rendering of curves by a factor of 2 / 'K' decreases it
'Z' will dump your current picture to the java console in a form which can be copied and pasted into the header of a7.java to be a new starting pic