Lighten or darken BufferedImages, or Images?

[Braden Steffaniak]

I have tried RescaleOp, however all that seems to do is purplify the BufferedImage. I am looking for something that looks like you are placing a 25% opaque black sheet over an image, a 50% and a 75%. And not a purple sheet.

Heres the code of what I was doing before:

this.pixelWidth = width * Main.scaleF;
this.pixelHeight = height * Main.scaleF;
		
material = Main.terrainSpriteSheet.getSubimage(x, y, width, height);
		
material = material.getScaledInstance(width * Main.scaleF, height * Main.scaleF, Image.SCALE_SMOOTH);
		
BufferedImage mat = new BufferedImage(pixelWidth, pixelHeight, BufferedImage.TRANSLUCENT);
mat.getGraphics().drawImage(material, 0, 0, null);
		
RescaleOp opp = new RescaleOp(.75f, 0, null);
opp.filter(mat, mat);
		
material = mat;

All it seems to do is make it more purple. Is there anything else that will work?

[Ulf Dittmer]

You can blend two images with a given alpha (which would be 0.25, 0.5 or 0.75 in your case) like this:

 
Graphics g = ... ;
g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER, alpha));
g.drawImage(image1, 0, 0, null);
g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER, 1.0f - alpha));
g.drawImage(image2, 0, 0, null);

Provided one of the images is completely black, this should produce the desired output.

[Braden Steffaniak]

That will work, thanks.