public double progressOnLevel(TileExtents extents) {
    // approximate percent complete within a bounding box by computing what % of the way through the columns we are
    var zoomBounds = extents.getForZoom(z);
    return 1d * (x - zoomBounds.minX()) / (zoomBounds.maxX() - zoomBounds.minX());
  }
Returns the tile containing a latitude/longitude coordinate at a given zoom level.
planetiler-core/src/main/java/com/onthegomap/planetiler/geo/TileCoord.java