# File lib/bio/graphics/ruler.rb, line 52
  def first_tick_position(start = @panel.display_start,
                          minor_tick = @minor_tick_distance)
    #  * Find position of first tick.
    #    Most of the time, we don't want the first tick on the very first
    #    basepair of the view. Suppose that would be position 333 in the
    #    sequence. Then the numbers under the major tickmarks would be:
    #    343, 353, 363, 373 and so on. Instead, we want 350, 360, 370, 380.
    #    So we want to find the position of the first tick.
    modulo_from_tick = (start % minor_tick)
    return (start + (modulo_from_tick > 0 ? (minor_tick - modulo_from_tick) : 0))
  end