Drawing directly onto the BufferStrategy

Newbie & Debugging Questions
#1

In previous project, I have done my Java2D rendering by drawing onto a BufferedImage and drawing that to a BufferStrategy. This allowed me to scale the image to acheive a low-resultion effect at higher resolution windows by drawing the image as


g.drawImage(image, 0, 0, width, height, null);

but when I make the window, I go


main.setPreferredSize(new Dimension(width * scale, height * scale));

Thus making it three times more spread out.

Anyways I just found out how much more efficient it is to draw directly onto the BufferStrategy instead of using a BufferedImage. So my question is:

How can I draw directly onto the BufferStrategy and still scale the image? Is this possible at all?

Thanks,
| Nathan

#2

Wouldn’t drawing directly on the BufferStrategy nullify its use? Isn’t its purpose to do the double buffering for you so you don’t have to keep track of the off-screen fully drawn image?

I’ve worded that badly, this is what I use

                // Create BufferStrategy
      BufferStrategy bs = getBufferStrategy();
		if (bs == null) {
			createBufferStrategy(3);
			return;
		}

                // Get BufferStategy's graphics object //
		Graphics g = bs.getDrawGraphics();
                // Clear the screen
		g.fillRect(0, 0, getWidth(), getHeight());

		int ww = WIDTH * SCALE;
		int hh = HEIGHT * SCALE;

                // draw on it
		g.drawImage(image, 0, 0, ww, hh, null);
                
                // dispose of it (finished drawing)
		g.dispose();
                // show it
		bs.show();
#3

When you are drawing you can cast your Graphics object to a Graphics2D object. Then call Graphics2D.scale(). Then do your drawing after calling scale. All future drawing calls will be scaled.

#4

Depending on exactly what drawing operations you are doing, it may be faster to draw at ‘normal’ scale into a VolatileImage, and draw that scaled to the BufferStrategy.