metronome

metronome.rb

$Tempo = 120.to_f

$Sounds = %w{ 2.mp3 1.mp3 1.mp3 1.mp3 }

$SoundsIdx = 0

def rest_time_from_tempo
  60.0 / $Tempo
end

$RestTime = rest_time_from_tempo

$Threads = {
  playing_sounds: Thread.new do
    loop do
      Thread.new { `aplay #{$Sounds[$SoundsIdx]}` }
      $SoundsIdx += 1
      $SoundsIdx = 0 if $SoundsIdx >= $Sounds.length
      sleep $RestTime
    end
  end,
  changing_tempo: Thread.new do
    loop do
      puts "tempo is #{$Tempo}"
      puts "enter new tempo between 10 and 1000"
      $Tempo = [[gets.chomp.to_f, 10.0].max, 1000.0].min
      $RestTime = rest_time_from_tempo
    end
  end
}

$Threads.values.each &:join