public ArrayList<MapEdge> getRoads(double x1, double y1, double x2, double y2) {
        if (nw.canZoom(x1, y1, x2, y2)) return nw.getRoads(x1, y1, x2, y2);
        if (ne.canZoom(x1, y1, x2, y2)) return ne.getRoads(x1, y1, x2, y2);
        if (sw.canZoom(x1, y1, x2, y2)) return sw.getRoads(x1, y1, x2, y2);
        if (se.canZoom(x1, y1, x2, y2)) return se.getRoads(x1, y1, x2, y2);
        return getEdges();
    }