Change alpha of image in java for method drawImage()

java graphics bufferedimage alpha drawimage
applemavs picture applemavs · Apr 14, 2013 · Viewed 9.5k times · Source

I'm trying to change the transparency of an image over time, and I'm doing this with the method drawImage() from java.awt.Graphics. I know there's a lot of different answers online about how to do this, but I can't find a one that is simple enough for me to understand and implement.

Let's just say I have a BufferedImage image, and I want to draw this image with a 50% opacity. How would I initialize image and what would I do to adjust the alpha level of the image when I draw it. It would be great if I could use the method drawImage() and do something with that to change the transparency of the image, but it's probably not that simple.

Answer

camickr picture camickr · Apr 14, 2013

Never tried it, but I think the basic code would be:

AlphaComposite ac = AlphaComposite.getInstance(AlphaComposite.SRC_OVER, alpha);
g2d.setComposite(ac);
g2d.drawImage(...);

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