docs: private static Cell getCentroidCell(Polygon polygon) {
          double area = 0.0;
          double x = 0.0;
          double y = 0.0;
  
          LineString exterior = polygon.getExteriorRing();
  
          for (int i = 0, n = exterior.getNumPoints() - 1, j = n - 1; i < n; j = i, i++) {
              Coordinate a = exterior.getCoordinateN(i);
              Coordinate b = exterior.getCoordinateN(j);
              double f = a.x * b.y - b.x * a.y;
              x += (a.x + b.x) * f;
              y += (a.y + b.y) * f;
              area += f * 3.0;
          }
          return new Cell(x / area, y / area, 0.0, polygon);
      }