I have written a graphics program that generates a lot of data points
and as each data point is calculated, it is placed on the chart.  I
decided to add each point as it is calculated, rather than to generate
all points and show the chart only when all points are done, as a bit of
eye-candy to keep the user interested.

The code fragments below shows how it is done:

===============
  public void addPoint(DataPoint point)
  {
    // Vector of graph points
    dataPoints.add(point);
    repaint();
  }

  public void paint(Graphics g)
  {
    Graphics2D g2d = (Graphics2D)g;

    // Draw X and Y axes, grid lines, and scale numbers.
    // (some code here)

    // Now draw the graph points in the dataPoints Vector.
    int numPoints = dataPoints.size();
    for (int i = 0; i < numPoints; i++)
    {
      // Various calculations to properply place each point
      // in the g2d space...

    }
  }
================

As each point is generated, it is put into the dataPoints vector
(through the addPoint() method), and then a repaint() invokes the
paint() method.  Note that the paint() method re-does everything.  Even
if I already have 200 points on the chart, and I add the 201st point,
all 201 points are redrawn just to achieve the visual effect of adding a
201st point to the chart.

As more points are added, things seem slower, since all points have to
be redrawn in order to add the last new point.

Question:  Is there a technique to just add one point to the EXISTING
chart without having to redraw the ENTIRE chart?