@Override
  public PackedCoordinateSequence copy() {
    return new PackedCoordinateSequence.Double(points.toArray(), components, components > 3 ? 1 : 0);
  }
A mutable {@link CoordinateSequence} that grows to fit new elements when {@code set*} methods are called.
planetiler-core/src/main/java/com/onthegomap/planetiler/reader/parquet/CoordinateSequenceBuilder.java