code: def render_tile(
      cells, ti, tj, render, params, metadata, layout, summary
  ):
      """
      Render each cell in the tile and stitch it into a single image
      """
      image_size = params["cell_size"] * params["n_tile"]
      tile = Image.new("RGB", (image_size, image_size), (255, 255, 255))
      keys = cells.keys()
  
      def density(cell, metadata):
          return len(cell["gi"])
  
      # if the user doesn't provide a scale function its just the density
      user_density = params.get("density_function", density)
  
      for i, key in enumerate(keys):
          print("cell", i + 1, "/", len(keys), end="\r")
          cell_image = render(
              cells[key], params, metadata, layout, summary
          )
          # stitch this rendering into the tile image
          ci = key[0] % params["n_tile"]
          cj = key[1] % params["n_tile"]
          xmin = ci * params["cell_size"]
          ymin = cj * params["cell_size"]
          xmax = (ci + 1) * params["cell_size"]
          ymax = (cj + 1) * params["cell_size"]
  
          if params.get("scale_density", False):
              cell_density = user_density(cells[key], metadata)
              # scale = density/summary["max_density"]
              # for now, user_max_density will be the same as max_density if the user didn't supply a fn
              scale = math.log(cell_density) / (
                  math.log(summary["user_max_density"]) or 1
              )
              owidth = xmax - xmin
              width = int(round(owidth * scale))
              if width < 1:
                  width = 1
              offsetL = int(round((owidth - width) / 2))
              offsetR = owidth - width - offsetL  # handle odd numbers
              # print("\n")
              # print("width", width, offsetL, offsetR)
              box = [
                  xmin + offsetL,
                  ymin + offsetL,
                  xmax - offsetR,
                  ymax - offsetR,
              ]
              resample = params.get("scale_type", Image.NEAREST)
              cell_image = cell_image.resize(
                  size=(width, width), resample=resample
              )
              # print(cell_image)
          else:
              box = [xmin, ymin, xmax, ymax]
  
          # print("box", box)
          tile.paste(cell_image, box)
      print("\n")
      return tile
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  from PIL import Image
  import math
label_desc: Use image node_id 1 for calling a global function with example usage: render_tile(cells, ti, tj, render, params, metadata, layout, summary) and returns: tile, len