No point can be added on the left hand side of the sweepline. A point can be dragged anywhere on the display area right to the sweepline. It can not be dragged across the sweepline. The user can delete a point by double-clicking it. Only points on the right hand side of the sweepline can be deleted.
Points Points have different colors.
Points of the closest pair are green. Points in the query band have black color. The last swept point has dark red color. All the other points are blue. Forward Buttons Clicking Forward button can move the sweepline to the next point.