import element.*;

public class Mirror
{
    public static void main(String args[])
    {
        DrawingWindow d = new DrawingWindow();
        int width = d.bounds().width();   // window width
        int height = d.bounds().height(); // and height
        Pt current, next;                 // points

        d.awaitMousePress();    // drawing starts with mouse press

        current = d.getMouse(); // move pen to initial location
        while (d.mousePressed())
        {
            next = d.getMouse();        // get next mouse position
            d.moveTo(current);          // draw the "right" image
            d.lineTo(next);

            // the "mirrored" points are same distance
            // away from bottom and right sides;
            // draw line between them
            d.moveTo(width-current.x(),height-current.y());
            d.lineTo(width-next.x(),height-next.y());

            // current point is basis for next line segment
            current = next;     
        }
    }
}