start = true; r.x = j; r.y = i;
r = new Rectangle(new Point(x, y));
    public MapLayer createDiff(MapLayer ml) {		        if (ml == null) {            return null;        }        Rectangle r = new Rectangle();        boolean start = false;        for (int i = bounds.y; i < bounds.height + bounds.y; i++) {            for (int j = bounds.x; j < bounds.width + bounds.x; j++) {                if (ml.getTileAt(j, i) != getTileAt(j, i)) {                    if (start) {                        r.width = Math.max(Math.abs(j - r.x), r.width);                        r.height = Math.max(Math.abs(i - r.y), r.height);                    } else {                        start = true;                        r.x = j;                        r.y = i;                    }                }            }        }        MapLayer diff = new MapLayer(r);        diff.copyFrom(ml);		        return diff;    }