A rough sketch of text wrapping into a constrained width

wrapper.coffee

textSize = (msg, font, size) ->
  bb = (GD.create(1,1)).stringFTBBox(black, font, size, 0, 0, 0, msg)
  [
    bb[2] - bb[0],
    bb[1] - bb[7]
  ]

chunkInputInto = (msg, splits) ->
  stepSize = Math.round(msg.length / splits)
  chunks = []

  for n in [0...splits]
    chunks[n] = msg[...stepSize]
    msg = msg[stepSize..]

    # Shift words down until the last space in this line and
    # give them back to the buffer
    while not /\s$/.test(chunks[n])
      chunkLen = chunks[n].length
      msg = "#{chunks[n][chunkLen - 1]}#{msg}"
      chunks[n] = chunks[n][...-1]
  return chunks.map (c) -> c.trim()

baloon = (msg, font="./ayp-template-images/arial.ttf", size=12, max=330) ->
  msg = msg.trim()
  [w, h] = textSize(msg, font, size)
  console.log "BB: ", [w, h], " of '#{msg}'"

  if w > max
    splits = Math.round(w / max)
    splits += 1 if w % max
    msg = chunkInputInto(msg, splits).join "\n"
  else
    msg

Doctor! My brain hurts!