Question

I am trying to rotate an image in Java, but when I do the transparency in the png goes away. Is there any way i can rotate the image AND keep the transparency?

          AffineTransform trans = new AffineTransform();
          trans.setTransform(identity);
          trans.translate(100, 100);
          trans.rotate( Math.toRadians(45) );

          gr.drawImage(image.getImage(), trans, this);

This makes the transparency in the png black, but

          gr.drawImage(image.getImage(), 0, 200, null);

Has no problem with the transparency.

Answer 1

Try to set rendering hints on Graphics2D object.

gr.setRenderingHint(RenderingHints.KEY_ALPHA_INTERPOLATION, RenderingHints.VALUE_ALPHA_INTERPOLATION_QUALITY );

Check reference for optimal settings.