private List<T> postFilterIntersecting(Geometry geom, List<?> items) {
    List<T> result = new ArrayList<>(items.size());
    for (Object item : items) {
      if (item instanceof GeomWithData<?>(var poly, var data) && poly.intersects(geom)) {
        @SuppressWarnings("unchecked") T t = (T) data;
        result.add(t);
      }
    }
    return result;
  }
Returns the data associated with all polygons intersecting {@code geom}.
planetiler-core/src/main/java/com/onthegomap/planetiler/geo/PolygonIndex.java