Hey everyone. I'm working on a 2D game that uses semi-transparent overlay images. The overlay images have 2 alpha values, 0 and 0.5. The code works and the images are drawn on top of my game board. However, its putting a lot of stress on my system when a lot of these images are displayed at once (if they are filling up half my screen, there is considerable lag). I think there is a faster way to draw my images, but I can't figure out what it is. Here is the code I use to load the images.

static BufferedImage getImage(String name) {
	BufferedImage image;
	try {
		image = ImageIO.read(new File(name));
	}
	catch (Exception e) {
		System.err.println("Error loading image file " + name + ".");
		image = new BufferedImage(1,1,BufferedImage.TYPE_INT_ARGB);
	}
	return image;
}

The image is then drawn onto the screen using g.drawImage() . Any ideas on how I could speed this up? If anyone needs more information please let me know. Thanks!

you could use opengl (LWJGL for example).

Ideally I'd prefer to not use OpenGL or DirectX if possible...

When I was working with Java2D there was a rather unique solution I found to this. I used an opaque BufferedImage the size of the screen that I would draw everything to (might have been volatile, not completely sure... sorry use LWJGL now), and then drawing this to the back buffer using an gfx.drawImage(img,0,0,null) call. The "gfx" reference was a Graphics2D obj that I got from a double-buffering BufferStrategy.

So simply its:
1: render everything to an opaque image acting as a fake back buffer (you might want to check image properties to ensure that it is opaque)
2: draw the image to the real back buffer
3: continue normally as if your rendering had just finished

I was never completely sure why it worked better (very significantly actually, improving from 25 to 60 FPS) but I was using it to draw a translucent gradient across the bottom part of the screen in a full screen game. I think that it might do something different with the blending of translucency (perhaps calculating as each thing is rendered to the third buffer?). You might want to give it a try.

I have some problem, when i draw an opaque image is very fast, but when images are translucent all become very slow...
I managed my image whit this code:
public void optimizing(GraphicsConfiguration cfg) {
BufferedImage newBuffer=cfg.createCompatibleImage(imm.getWidth(),imm.getHeight(),imm.TRANSLUCENT);
Graphics2D bg2=newBuffer.createGraphics();
bg2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
bg2.drawImage(imm,0,0,null);
imm.flush();
imm=null;
imm=newBuffer;
bg2.dispose();
}

But draw translucent image are very slow anyway... whit -Dsun.java2d.translaccel=true is more slow...

There are any way?

I have some problem, when i draw an opaque image is very fast, but when images are translucent all become very slow...
I managed my image whit this code:

public void optimizing(GraphicsConfiguration cfg) {		BufferedImage newBuffer=cfg.createCompatibleImage(imm.getWidth(),imm.getHeight(),imm.TRANSLUCENT);		Graphics2D bg2=newBuffer.createGraphics();		bg2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);		bg2.drawImage(imm,0,0,null);		imm.flush();		imm=null;		imm=newBuffer;		bg2.dispose();}

But draw translucent image are very slow anyway... whit -Dsun.java2d.translaccel=true is more slow...

There are any way?

Could you post an example of your rendering code? It would be very helpful to diagnosing the problem.