class Music::Performance::PortamentoConverter

Public Class Methods

portamento_elements(start_pitch, target_pitch, cents_per_step, duration, accented) click to toggle source
# File lib/music-performance/conversion/portamento_converter.rb, line 16
def self.portamento_elements(start_pitch, target_pitch, cents_per_step, duration, accented)
  pitches = portamento_pitches(start_pitch, target_pitch, cents_per_step)
  subdur = Rational(duration, pitches.size)
  pitches.map do |pitch|
    SlurredElement.new(subdur, pitch, accented)
  end
end
portamento_pitches(start_pitch, target_pitch, cents_per_step) click to toggle source
# File lib/music-performance/conversion/portamento_converter.rb, line 5
def self.portamento_pitches(start_pitch, target_pitch, cents_per_step)
  start, finish = start_pitch.total_cents, target_pitch.total_cents
  step_size = finish >= start ? cents_per_step : -cents_per_step
  nsteps = ((finish - 1 - start) / step_size.to_f).ceil
  cents = Array.new(nsteps+1){|i| start + i * step_size }
  
  cents.map do |cent|
    Music::Transcription::Pitch.new(cent: cent)
  end
end