title: how do I mark special data points in JChart2D?
body: <p>In JChart2D points from a series can be plotted with little circles or a line drawn through the points. I need to draw the user's attention to certain specific points.</p>
  
  <p>How would I mark the occasional point with filled-in circles or some other kind of symbol.</p>
  
  <p>The vertical bar painter provided, seems to change the entire plot to a vertical bar chart (at the point it occurs and also "retroactively" to the older points).  I do not want that.  I just need to <b>make a single point look special</b>, for example, the point at X=5.</p>
  
  <pre><code>    Chart2D chart = new Chart2D();
      ITrace2D myTrace = new Trace2DLtd(100); 
      myTrace.setColor(Color.RED);
      myTrace.setTracePainter(new TracePainterDisc()); // circle; not filled
  
      chart.addTrace(myTrace);
  
      JFrame frame = new JFrame(Constants.graphTitle);
      frame.getContentPane().add(chart);
  
      frame.setSize(200, 200);
      frame.addWindowListener(
          new WindowAdapter(){
            public void windowClosing(WindowEvent e){
                System.exit(0);
            }
          }
        );
      frame.setVisible(true);
  
      List&lt;Point&gt; list = Helper.makeList();
      for (Point p: list)
      {
          if (p.x != 5)
              myTrace.addPoint(p.x, p.y);
          else
          {
              // MAKE THIS POINT LOOK DIFFERENT, BUT HOW?
              myTrace.addPoint(p.x, p.y);
          }
      }
    }
  }
  </code></pre>