docs: public MapReadResult readPoiData(Tile upperLeft, Tile lowerRight) {
          if (upperLeft.tileX > lowerRight.tileX || upperLeft.tileY > lowerRight.tileY) {
              new IllegalArgumentException("upperLeft tile must be above and left of lowerRight tile");
          }
          MapReadResult result = new MapReadResult();
          for (int x = upperLeft.tileX; x <= lowerRight.tileX; x++) {
              for (int y = upperLeft.tileY; y <= lowerRight.tileY; y++) {
                  Tile current = new Tile(x, y, upperLeft.zoomLevel, upperLeft.tileSize);
                  result.add(readPoiData(current), false);
              }
          }
          return result;
      }