filter communicates to plots through enter key.  Points that make it through the filter are deleted and recreated in a highlightted color so that they sit on top of the existing data and are clearly visible.  When the clear search bar button is pressed the points that have been recreated are then deleted and recreated once more once again in the original dull coloring.  This is fast if your search results in a small number of points, but slow when you search for a large number of points.  Searching for all of the good points, for example, will be very slow.