dust_in_the_wind.rb

dust_in_the_wind.rb

# Iterates through its elements, starting at the beginning, forever.
class CircularList
  def initialize values
    @values = values
    @index = 0
  end

  def next
    value = @values[@index]
    @index += 1
    @index = 0 if @index == @values.length
    value
  end
end

def pick strings
  finger_for_string = {
    2 => :thumb,
    3 => :thumb,
    4 => :index,
    5 => :middle
  }

  strings = [strings] if not strings.is_a? Array
  puts "Pick #{strings.join(", ")} with #{strings.map { |s| finger_for_string[s] }.join(", ")}"
end

# "Travis pick" fingerpicking pattern. 7 notes total.
def travis_pattern
  (1..2).each do |x|
    if x == 1
      pick [2, 5]
    else x == 2
      pick 2
      pick 5
    end
    pick 3
    pick 4
  end
end

chord = "C"
fifth_string = CircularList.new [1, "0/open", 3]

(1..4).each do
  puts "=== CHORD CHANGE: Switch to #{chord}"
  (1..4).each do
    puts "Chord #{chord} with 5th string at #{fifth_string.next}"
    travis_pattern
  end

  chord = case chord
    when "A" then "C"
    when "C" then "A"
  end
end

output.txt

=== CHORD CHANGE: Switch to C
Chord C with 5th string at 1
Pick 2, 5 with thumb, middle
Pick 3 with thumb
Pick 4 with index
Pick 2 with thumb
Pick 5 with middle
Pick 3 with thumb
Pick 4 with index
Chord C with 5th string at 0/open
Pick 2, 5 with thumb, middle
Pick 3 with thumb
Pick 4 with index
Pick 2 with thumb
Pick 5 with middle
Pick 3 with thumb
Pick 4 with index
Chord C with 5th string at 3
Pick 2, 5 with thumb, middle
Pick 3 with thumb
Pick 4 with index
Pick 2 with thumb
Pick 5 with middle
Pick 3 with thumb
Pick 4 with index
Chord C with 5th string at 1
Pick 2, 5 with thumb, middle
Pick 3 with thumb
Pick 4 with index
Pick 2 with thumb
Pick 5 with middle
Pick 3 with thumb
Pick 4 with index
=== CHORD CHANGE: Switch to A
Chord A with 5th string at 0/open
Pick 2, 5 with thumb, middle
Pick 3 with thumb
Pick 4 with index
Pick 2 with thumb
Pick 5 with middle
Pick 3 with thumb
Pick 4 with index
Chord A with 5th string at 3
Pick 2, 5 with thumb, middle
Pick 3 with thumb
Pick 4 with index
Pick 2 with thumb
Pick 5 with middle
Pick 3 with thumb
Pick 4 with index
Chord A with 5th string at 1
Pick 2, 5 with thumb, middle
Pick 3 with thumb
Pick 4 with index
Pick 2 with thumb
Pick 5 with middle
Pick 3 with thumb
Pick 4 with index
Chord A with 5th string at 0/open
Pick 2, 5 with thumb, middle
Pick 3 with thumb
Pick 4 with index
Pick 2 with thumb
Pick 5 with middle
Pick 3 with thumb
Pick 4 with index
=== CHORD CHANGE: Switch to C
Chord C with 5th string at 3
Pick 2, 5 with thumb, middle
Pick 3 with thumb
Pick 4 with index
Pick 2 with thumb
Pick 5 with middle
Pick 3 with thumb
Pick 4 with index
Chord C with 5th string at 1
Pick 2, 5 with thumb, middle
Pick 3 with thumb
Pick 4 with index
Pick 2 with thumb
Pick 5 with middle
Pick 3 with thumb
Pick 4 with index
Chord C with 5th string at 0/open
Pick 2, 5 with thumb, middle
Pick 3 with thumb
Pick 4 with index
Pick 2 with thumb
Pick 5 with middle
Pick 3 with thumb
Pick 4 with index
Chord C with 5th string at 3
Pick 2, 5 with thumb, middle
Pick 3 with thumb
Pick 4 with index
Pick 2 with thumb
Pick 5 with middle
Pick 3 with thumb
Pick 4 with index
=== CHORD CHANGE: Switch to A
Chord A with 5th string at 1
Pick 2, 5 with thumb, middle
Pick 3 with thumb
Pick 4 with index
Pick 2 with thumb
Pick 5 with middle
Pick 3 with thumb
Pick 4 with index
Chord A with 5th string at 0/open
Pick 2, 5 with thumb, middle
Pick 3 with thumb
Pick 4 with index
Pick 2 with thumb
Pick 5 with middle
Pick 3 with thumb
Pick 4 with index
Chord A with 5th string at 3
Pick 2, 5 with thumb, middle
Pick 3 with thumb
Pick 4 with index
Pick 2 with thumb
Pick 5 with middle
Pick 3 with thumb
Pick 4 with index
Chord A with 5th string at 1
Pick 2, 5 with thumb, middle
Pick 3 with thumb
Pick 4 with index
Pick 2 with thumb
Pick 5 with middle
Pick 3 with thumb
Pick 4 with index