class HexaPDF::Type::CIDFont

def widths
  cache(:widths) do
    result = {}
    index = 0
    array = self[:W] || []
    while index < array.size
      entry = array[index]
      value = array[index + 1]
      if value.kind_of?(Array)
        value.each_with_index {|width, i| result[entry + i] = width }
        index += 2
      else
        width = array[index + 2]
        entry.upto(value) {|cid| result[cid] = width }
        index += 3
      end
    end
    result
  end
end