Change brightness of jframe

Question

I have a program, and it runs in a jframe in full screen exclusive mode. I am trying to change the brightness of the jframe. I was wondering how i would implement this. I thought it might be possible to change all the colors of the images getting drawn to the jframe and make them brighter, but it still does not change how bright the screen actually is. How do programs normally implement something like this.

Answer 1

At the end of your draw loop:

g.setColor(new Color(0, 0, 0, 0.5f)); // 50% darker (change to 0.25f for 25% darker)
g.fillRect(0, 0, width, height);

Answer 2

I'm not sure if this is the best way, but it works. Override the public void paint(Graphics g)method of your JPanel, then first call the super.paint(g); and paint a transparent black rectangle above it.

Something like this:

private static Color BG = new Color(0, 0, 0, 100);

@Override
public void paint(Graphics g) {
    super.paint(g);
    g2.setColor(BG);
    g.fillRect(0, 0, getWidth(), getHeight());
    g.dispose();
}

Change the Color with a new value instead of 100 to change the darkness.