Class: Deftones::Effects::Chorus

Inherits:
Core::Effect show all
Includes:
ModulationControl
Defined in:
lib/deftones/effect/chorus.rb

Instance Attribute Summary collapse

Attributes inherited from Core::Effect

#wet

Instance Method Summary collapse

Methods included from ModulationControl

#bipolar_modulation_value, #cancel_stop, #clear_modulation_event, #dispose, #initialize_modulation_control, #modulation_active_at?, #modulation_frequency, #modulation_phase_for, #modulation_sample_for, #modulation_type, #normalize_modulation_type, #resolve_modulation_time, #resolve_modulation_transport_time, #restart, #schedule_modulation_event, #start, #state, #stop, #sync, #synced?, #unipolar_modulation_value, #unsync

Methods inherited from Core::Effect

#multichannel_process?, #normalize_channel_output, #process, #process_effect

Constructor Details

#initialize(frequency: 1.5, depth: 0.003, delay_time: 0.015, feedback: 0.0, spread: 180.0, type: :sine, context: Deftones.context, **options) ⇒ Chorus

Returns a new instance of Chorus.



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# File 'lib/deftones/effect/chorus.rb', line 10

def initialize(
  frequency: 1.5,
  depth: 0.003,
  delay_time: 0.015,
  feedback: 0.0,
  spread: 180.0,
  type: :sine,
  context: Deftones.context,
  **options
)
  super(context: context, **options)
  @frequency = frequency.to_f
  @depth = depth.to_f
  @delay_time = delay_time.to_f
  @feedback = feedback.to_f
  @spread = spread.to_f
  @type = normalize_modulation_type(type)
  @phase = 0.0
  @delay_lines = []
  initialize_modulation_control
end

Instance Attribute Details

#delay_time ⇒ Object

Returns the value of attribute delay_time.



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# File 'lib/deftones/effect/chorus.rb', line 8

def delay_time
  @delay_time
end

#depth ⇒ Object

Returns the value of attribute depth.



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# File 'lib/deftones/effect/chorus.rb', line 8

def depth
  @depth
end

#feedback ⇒ Object

Returns the value of attribute feedback.



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# File 'lib/deftones/effect/chorus.rb', line 8

def feedback
  @feedback
end

#frequency ⇒ Object

Returns the value of attribute frequency.



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# File 'lib/deftones/effect/chorus.rb', line 8

def frequency
  @frequency
end

#spread ⇒ Object

Returns the value of attribute spread.



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# File 'lib/deftones/effect/chorus.rb', line 8

def spread
  @spread
end

#type ⇒ Object

Returns the value of attribute type.



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# File 'lib/deftones/effect/chorus.rb', line 8

def type
  @type
end

Instance Method Details

#channel_phase_offset(channel_index, channels) ⇒ Object (private) 



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# File 'lib/deftones/effect/chorus.rb', line 66

def channel_phase_offset(channel_index, channels)
  return 0.0 if channels <= 1 || channel_index.zero?

  (@spread / 360.0) * (channel_index.to_f / [channels - 1, 1].max)
end

#ensure_delay_lines(channels) ⇒ Object (private) 



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# File 'lib/deftones/effect/chorus.rb', line 59

def ensure_delay_lines(channels)
  required = [channels.to_i, 1].max
  while @delay_lines.length < required
    @delay_lines << DSP::DelayLine.new((0.1 * context.sample_rate).ceil)
  end
end

#process_effect_block(input_block, num_frames, start_frame, _cache) ⇒ Object (private) 



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# File 'lib/deftones/effect/chorus.rb', line 34

def process_effect_block(input_block, num_frames, start_frame, _cache)
  output_channels = [input_block.channels, 2].max
  source = input_block.fit_channels(output_channels)
  ensure_delay_lines(output_channels)
  output = Array.new(output_channels) { Array.new(num_frames, 0.0) }

  num_frames.times do |index|
    current_time = (start_frame + index).to_f / context.sample_rate
    base_phase = modulation_phase_for(current_time)

    output_channels.times do |channel_index|
      phase = base_phase.nil? ? nil : base_phase + channel_phase_offset(channel_index, output_channels)
      modulation = unipolar_modulation_value(phase, default: 0.5)
      delay = (@delay_time + (@depth * modulation)) * context.sample_rate
      output[channel_index][index] = @delay_lines[channel_index].tap(
        delay,
        input_sample: source.channel_data[channel_index][index],
        feedback: @feedback
      )
    end
  end

  Core::AudioBlock.from_channel_data(output)
end