Class: Feep::Scale

Inherits:
Object
  • Object
show all
Defined in:
lib/feep/scale.rb

Instance Method Summary collapse

Instance Method Details

#play_scale(options) ⇒ Object

plays the musical scale with Feep



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# File 'lib/feep/scale.rb', line 11

def play_scale(options)
  unless SCALES.include?(options[:scale].to_sym)
    Utils.print_error(:invalid_scale)
  end

  valid_notes = NOTES | NOTES_ALT | FREQS
  freq = Utils::convert_note_to_freq(options[:freq_or_note]).to_f

  if valid_notes.include?(freq)
    steps = SCALES[options[:scale].to_sym].split(',')

    freq_index = FREQS.index(freq)

    feep_options = {
      :freq_or_note => freq.to_s, 
      :waveform => options[:waveform], 
      :volume => options[:volume], 
      :duration => options[:duration], 
      :save => options[:save], 
      :verbose => options[:verbose]
    }

    # play number of degrees of scale supplied or one octave by default
    degrees = options[:degrees] || steps.length

    if options[:verbose]
      puts "Playing a #{options[:scale]} scale..."
    end

    1.upto(degrees.to_i) {|deg|
      if options[:verbose]
        puts "note: #{NOTE_FREQ.key(freq)}, freq: #{freq}"
      end
      
      # play note
      Feep::Base.new(feep_options)
  
      # go to the next note in the scale
      freq_index += steps[deg].to_i

      # set new note to play next time around
      freq = feep_options[:freq_or_note] = FREQS[freq_index].to_s
    }
  else
    Utils.print_error(:invalid_scale_root_note)
  end
end