def points
      longest_arr = layers.inject(nil) do |longest, layer|
        longest = layer.points if (longest.nil? || longest.size < layer.points.size)
        longest
      end
      
      summed_points = (0...longest_arr.size).map do |idx|
        layers.inject(nil) do |sum, layer|
          if sum.nil? && !layer.points[idx].nil?
            sum = layer.points[idx]
          elsif !layer.points[idx].nil?
            sum += layer.points[idx]
          end
          
          sum
        end
      end

      summed_points
    end
def points
      longest_arr = layers.inject(nil) do |longest, layer|
        longest = layer.points if (longest.nil? || longest.size < layer.points.size)
        longest
      end
      
      summed_points = (0...longest_arr.size).map do |idx|
        layers.inject(nil) do |sum, layer|
          if sum.nil? && !layer.points[idx].nil?
            sum = layer.points[idx]
          elsif !layer.points[idx].nil?
            sum += layer.points[idx]
          end
          
          sum
        end
      end

      summed_points
    end
TODO, special points accessor