Subsitute drawImage by nativa drawing code

Hi,
I'm not quite sure this is the right forum to post my question. It's been a while since I visited these fora and there used to be a forum specifically for Java 2D topics, but I can't seem to find it. So I'll post it here and hope I guessed right.
I was wondering about some drawing issue I had some time ago. I made an application using a custom, rather complex, backgroundimage and it started up pretty slow because it needed to load and draw the image. And I was wondering if it would be faster and more memory-efficient if in stead of using the drawImage()-method one used 'native' drawing code. You could make a program that reads an image and, using the provided array of data, puts together a sequence of drawing instructions like drawPoint with specified color or drawLine with the correct color so that the image generated from this block of code is exactly the same as the image from the resourcefile. And so my question is if this would be preferable to using the drawImage-method, if it would be faster and more memory-efficient (seeing that the code to do this would probably be a lot smaller than the actual imagefile and you also wouldn't need a load-buffer)?
Thanks in advance,
Sam

Thanks for all your help so far.
However, having changed gameLoop to:
    public void gameLoop() {
        long startTime = System.currentTimeMillis();
        long currTime = startTime;
        while (isRunning) {
            long elapsedTime = System.currentTimeMillis() - currTime;
            currTime += elapsedTime;
            update(elapsedTime);
            screen.repaint();
            screen.update();
    }and paintComponent to:
    public void paintComponent(Graphics g){
     game.draw(getGraphics());
    }I now get a NullPointerException which traces back to GameCore.draw then Screen.paintComponent, then JComponent.paint, etc. (it's a long one, and i don't know how to copy it here from the command prompt). Why's that happening?
Thanks
Edit: you can actually continue playing after the nullpointerexception has reared its head - it doesn't affect anything, but the screen is now ALL flickering, whereas in the original problem the background image was fine, but the images that made up the tiles in the map were flickering. Now, everything in the JFrame flickers.
Edited by: Pulkse.co.uk on Jun 19, 2009 2:58 AM

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All these apply to the Win32 OSs.
>
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in Win32, Linux and possibly Solaris (in that order).
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>
>
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Subsitute drawImage by nativa drawing code

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