Method: Musicality::DrumPattern#initialize

Defined in:
lib/musicality/composition/sequencing/drum_machine/drum_pattern.rb

#initialize(duration, part_portions) ⇒ DrumPattern

Returns a new instance of DrumPattern.



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# File 'lib/musicality/composition/sequencing/drum_machine/drum_pattern.rb', line 15

def initialize duration, part_portions
  @duration = duration

  non_drumpart_names = part_portions.select do |part_name|
    !DRUM_PARTS.include?(part_name)
  end
  if non_drumpart_names.any?
    raise ArgumentError, "Part names used that are not drum parts: #{non_drumpart_names.inspect}"
  end

  accent_offsets = if part_portions.has_key?(DrumParts::ACCENT)
    DrumPattern.determine_accent_offsets(
      part_portions.delete(DrumParts::ACCENT).to_rhythm_class.to_rhythm(duration))
  else
    []
  end

  @part_notes = Hash[ part_portions.map do |part_name, portions|
    pitch = DRUM_PART_PITCHES[part_name] || DUMMY_PITCH
    notes = portions.to_rhythm_class.to_rhythm(duration).to_notes(pitch)
    DrumPattern.apply_accents(notes, accent_offsets)
    [ part_name, notes ]
  end ]
end