static MidpointSmoother smoothMidpoint(int iters) {
    return new MidpointSmoother().setIters(iters);
  }
Returns a pipeline that smooths an input geometry by joining the midpoint of each edge of lines or polygons in the
order in which they are encountered.
planetiler-core/src/main/java/com/onthegomap/planetiler/geo/GeometryPipeline.java