[JAVA2D] Performace when drawing graphs

[Mr H. Morgan]

Hi,

I am drawing scientific graphs consisting of a large number (over 1000) of
unconnected lines.  The user can zoom in using a JSlider.  It takes around 50
milliseconds to perform a zoom, and this flickers when the slider is dragged.  I
tried double buffering and this increased the time it took to draw ten fold.

Should I be able to get better performance with java 2D.  Does anyone have any
suggestions about how to improve my code.  Any help would be greatly
appreciated.

I am running it on a Sun Ultra 10 under solaris.

I include my code for doing the drawing.

void drawGraph(Graphics g)
  {
    g2d = (Graphics2D)g;
    int i;
    at = new AffineTransform();
    g2d.translate(xPos, yPos);
    at.setToScale(factor, factor);
    g2d.transform(at);
    g2d.translate(-xPos, -yPos);

// Draw Grid
    g2d.setColor(Color.red);
    for(i=0; i<20; ++i)
    {
        j = i*size;
        g2d.drawLine(i*size,0,i*size,(19 * size));
    }

    for(i=0; i<20; ++i)
    {
        j =  i*size;
        g2d.drawLine(0,i*siz,(19 * size),i*size);
    }

    g2d.setColor(Color.blue);

// Draw Line
    drawLineToPoints(g2d, xValues1, yValues1, xValues2, yValues2);
  }

// Function to draw the line
  void drawLineToPoints(Graphics2D g2d, Vector xValues1, Vector yValues1, Vector
xValues2, Vector yValues2)
  {
        for(int a=0; a<xValues1.size(); ++a)
        {
                g2d.drawLine(getInt(xValues1, (a)),((19 * size + 1) -
getInt(yValues1, (a))),getInt(xValues2, (a)),((19 * size + 1) - getInt(yValues2,
(a))));
        }
  }

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