Re: Translucent volatile image appears opaque

"Knute Johnson" <nospam@rabbitbrush.frazmtn.com> wrote in message
news:dc%%n.10095$Zp1.6880@newsfe15.iad...


[...]

I have adapted your SSCCE for using a volatile image as below. The result
is that the VI has a background of opaque white and paints over the blue
background of the panel. How can I get it to be translucent? As you can
see I am explicitly creating a translucent image.

import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Transparency;
import java.awt.image.VolatileImage;

import javax.swing.JFrame;
import javax.swing.JPanel;

public class VITest extends JPanel {

   private VolatileImage vi;

   public VITest() {
      setPreferredSize(new Dimension(500, 400));
      setBackground(Color.BLUE);
   }

   public static void main(final String[] args) {
      EventQueue.invokeLater(new Runnable() {

         @Override
         public void run() {
            final JFrame f = new JFrame();
            f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
            final VITest t = new VITest();
            f.add(t);
            f.pack();
            f.setVisible(true);
            t.init();
         }
      });
   }

   private void createVI() {
      vi = getGraphicsConfiguration().createCompatibleVolatileImage(400,
300, Transparency.TRANSLUCENT);
   }

   private void init() {
      createVI();
      renderToVI();
   }

   @Override
   public void paintComponent(final Graphics g) {
      super.paintComponent(g);
      do {
         final int returnCode = vi.validate(getGraphicsConfiguration());
         if (returnCode == VolatileImage.IMAGE_RESTORED) {
            renderToVI();
         } else if (returnCode == VolatileImage.IMAGE_INCOMPATIBLE) {
            createVI();
            renderToVI();
         }
         final Graphics2D g2d = (Graphics2D)g;
         g2d.drawImage(vi, 0, 0, this);
      } while (vi.contentsLost());
   }

   private void renderToVI() {
      do {
         if (vi.validate(getGraphicsConfiguration()) ==
VolatileImage.IMAGE_INCOMPATIBLE) {
            createVI();
         }
         final Graphics2D g = vi.createGraphics();
         g.setColor(Color.BLACK);
         g.drawString("Hello World", 5, 20);
         g.dispose();
      } while (vi.contentsLost());
   }
}

--
And loving it,

-Qu0ll (Rare, not extinct)
_________________________________________________
Qu0llSixFour@gmail.com
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