docs: function featurePBFReader(tag, feature, pbf) {
    if (tag == 1) {
      feature.id = pbf.readVarint();
    } else if (tag == 2) {
      const end = pbf.readVarint() + pbf.pos;
      while (pbf.pos < end) {
        const key = feature.layer.keys[pbf.readVarint()];
        const value = feature.layer.values[pbf.readVarint()];
        feature.properties[key] = value;
      }
    } else if (tag == 3) {
      feature.type = pbf.readVarint();
    } else if (tag == 4) {
      feature.geometry = pbf.pos;
    }
  }