/** * Return the world's background image. The image may be used to draw onto the world's background. * * @return The background image */ public GreenfootImage getBackground() { if (backgroundImage == null) { backgroundImage = new GreenfootImage(getWidthInPixels(), getHeightInPixels()); backgroundImage.setColor(DEFAULT_BACKGROUND_COLOR); backgroundImage.fill(); backgroundIsClassImage = false; } else if (backgroundIsClassImage) { // Make the image a copy of the original to avoid modifications // to the original. backgroundImage = backgroundImage.getCopyOnWriteClone(); backgroundIsClassImage = false; } return backgroundImage; }