code: public Bbox getBounds() {
  		double w = mapWidth * getResolution();
  		double h = mapHeight * getResolution();
  		double x = getPosition().getX() - w / 2;
  		double y = getPosition().getY() - h / 2;
  		return new Bbox(x, y, w, h);
  	}
docs: Given the information in this ViewPort object, what is the currently visible area? This value is expressed in
  world coordinates.
  
  @return Returns the bounding box that covers the currently visible area on the map.