import org.eclipse.swt.SWT;
import org.eclipse.swt.events.*;
import org.eclipse.swt.graphics.*;
import org.eclipse.swt.widgets.*;
import org.eclipse.swt.layout.*;
import org.eclipse.swt.custom.*;

/**
 * This code probably looks ugly, but whatever. I am now releasing this into the Public Domain. Do with it what you will.
 *
 * @author Remy Suen
 */
public class A {

	private boolean isDragging = false;

	private int downX = -1;

	private int downY = -1;

	private int upX = -1;

	private int upY = -1;

	private GC gc;

	private Shell shell;

	public A() {
		final Display display = new Display();
		GC context = new GC(display);
		final Image image = new Image(display, display.getBounds());
		context.copyArea(image, 0, 0);
		context.dispose();
		Color color = new Color(display, 255, 255, 255);
		
		shell = new Shell(display, SWT.NO_TRIM);
		shell.setLayout(new FillLayout());
		shell.setText("Image");
		shell.setBounds(display.getBounds());
		gc = new GC(shell);
		gc.setForeground(color);
		shell.addPaintListener(new PaintListener() {
			public void paintControl(PaintEvent e) {
				gc.drawImage(image, 0, 0);
			}
		});

		shell.addMouseListener(new MouseAdapter() {
			public void mouseDown(MouseEvent e) {
				isDragging = true;
				System.out.println(e.x + "\t" + e.y);
				downX = e.x;
				downY = e.y;
			}

			public void mouseUp(MouseEvent e) {
				isDragging = false;
				upX = e.x;
				upY = e.y;
				gc.drawImage(image, 0, 0);
			}
		});

		shell.addMouseMoveListener(new MouseMoveListener() {
			public void mouseMove(MouseEvent e) {
				if (isDragging) {
					gc.drawImage(image, 0, 0);
					gc.drawRectangle(downX, downY, e.x - downX, e.y - downY);
				}
			}
		});

		shell.open();
		while (!shell.isDisposed()) {
			if (!display.readAndDispatch()) display.sleep();
		}
		image.dispose();
		color.dispose();
		display.dispose();
	}

	public static void main(String[] args) {
		A a = new A();
	}
}