I tried the below code for taking full page screenshot. But only the visible area is captured,
public void Fullscreen (WebDriver driver)
{
try {
final Screenshot screenshot = new AShot().shootingStrategy(ShootingStrategies.viewportPasting(1000)).takeScreenshot(driver);
final BufferedImage image = screenshot.getImage();
ImageIO.write(image, "PNG", new File("D:\\" + "AShot_BBC_Entire.png"));
} catch(Exception e){
System.out.println(e.getMessage());
}
}
Want to add answer in case when you don't know what kind of screen is used. (retina or not)
In this case you need find devicePixelRatio of browser window:
Then you can use ShootingStrategy with scaling;