MouseMotionListener

[hubikmar]

Hi,
I am writting a simple graphics editor and I am having a trouble with
mouseMotionListener speed performance. I write a simple class to demonstrate the issue. It basically just counts the Euklidiean distance between two registered points measured in pixels while the mouse is dragged, stores it in set and when mouse is released, it prints the result. I think it really should not slow down the listener though the distance between two points can be, if you drag the mouse a bit fast, more than 50 pixels. The actual trouble I have in my graphic editor, which is caused by this, looks like this.
http://www.imagebanana.com/view/6eh87b2t/obr.png

Thanks a lot

CODE

public class ZkouskaMouse extends JPanel {

    public ZkouskaMouse() {
	setPreferredSize(new Dimension(600, 600));
	MyAdapter adapter = new MyAdapter();
	addMouseMotionListener(adapter);
	addMouseListener(adapter);
    }

    private static void createAndShowGUI() {
	//Create and set up the window.
	JFrame frame = new JFrame("TEST");
	frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

	//Create and set up the content pane.
	JComponent newContentPane = new ZkouskaMouse();
	newContentPane.setOpaque(true); //content panes must be opaque
	frame.setContentPane(newContentPane);

	//Display the window.
	frame.pack();
	frame.setLocation(new Point(100, 0));
	frame.setVisible(true);
    }

    public static void main(String[] args) {
	//Schedule a job for the event-dispatching thread:
	//creating and showing this application's GUI.
	javax.swing.SwingUtilities.invokeLater(new Runnable() {

	    public void run() {
		createAndShowGUI();
	    }
	});
    }
    class MyAdapter extends MouseAdapter {

	Point pocBod = new Point();
	Point pom1;
	boolean first = false;
	Set<Double> set = new HashSet<Double>();

	@Override
	public void mouseDragged(MouseEvent e) {
	    if (first) {
		pom1 = new Point(pocBod.x, pocBod.y);
		first = false;
	    }
	    double a = Math.sqrt(Math.pow(e.getPoint().x - pom1.x, 2) + Math.pow(e.getPoint().y - pom1.y, 2));
	    set.add(a);
	    pom1 = e.getPoint();
	}

	@Override
	public void mousePressed(MouseEvent e) {
	    pocBod = e.getPoint();
	    first = true;
	}

	@Override
	public void mouseReleased(MouseEvent e) {
	    for (Double double1 : set) {
		System.out.println(double1);
	    }
	    set.clear();
	    System.out.println("");
	}
    }
}

[camickr]

MouseEvents are NOT generated for every pixel when the mouse is moved. There fore you need to interpolate between points or use the drawLine(...) method to draw a line between the two points.

[hubikmar]

Thank you a lot.The drawLine works great. Here is how it looks now.
obr2.png - Bilder und Fotos kostenlos auf ImageBanana hochladen