public double size(Unit.Length length) {
    return canBePolygon() ? Math.sqrt(length.base().area(this)) : length.base().length(this);
  }
Returns the length of this geometry if it is a line or the square root of the area if it is a polygon in units of
{@link Unit.Length}.
planetiler-core/src/main/java/com/onthegomap/planetiler/geo/WithGeometry.java