Class: Deftones::Source::PWMOscillator

Inherits:
Core::Source show all
Defined in:
lib/deftones/source/pwm_oscillator.rb

Instance Attribute Summary collapse

Attributes inherited from Core::Source

#mute, #onstop, #volume

Instance Method Summary collapse

Methods inherited from Core::Source

#active_at?, #apply_volume!, #cancel_stop, #clear_transport_event, #dispose, #mute?, #notify_stop_in_window, #number_of_inputs, #render, #render_block, #resolve_time, #resolve_transport_time, #restart, #schedule_transport_event, #source_type, #start, #state, #stop, #sync, #synced?, #unsync, #uses_legacy_render_for_block?

Constructor Details

#initialize(frequency: 440.0, modulation_frequency: 0.5, modulation_depth: 0.4, pulse_width: 0.5, detune: 0.0, context: Deftones.context) ⇒ PWMOscillator

Returns a new instance of PWMOscillator.



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# File 'lib/deftones/source/pwm_oscillator.rb', line 8

def initialize(frequency: 440.0, modulation_frequency: 0.5, modulation_depth: 0.4,
               pulse_width: 0.5, detune: 0.0, context: Deftones.context)
  super(context: context)
  @frequency = Core::Signal.new(value: frequency, units: :frequency, context: context)
  @modulation_frequency = Core::Signal.new(value: modulation_frequency, units: :frequency, context: context)
  @modulation_depth = Core::Signal.new(value: modulation_depth, units: :number, context: context)
  @detune = Core::Signal.new(value: detune, units: :number, context: context)
  @base_width = pulse_width.to_f
  @phase = 0.0
  @modulation_phase = 0.0
end

Instance Attribute Details

#detune ⇒ Object

Returns the value of attribute detune.



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# File 'lib/deftones/source/pwm_oscillator.rb', line 6

def detune
  @detune
end

#frequency ⇒ Object (readonly)

Returns the value of attribute frequency.



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# File 'lib/deftones/source/pwm_oscillator.rb', line 6

def frequency
  @frequency
end

#modulation_depth ⇒ Object (readonly) Also known as: modulationDepth

Returns the value of attribute modulation_depth.



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# File 'lib/deftones/source/pwm_oscillator.rb', line 6

def modulation_depth
  @modulation_depth
end

#modulation_frequency ⇒ Object (readonly) Also known as: modulationFrequency

Returns the value of attribute modulation_frequency.



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# File 'lib/deftones/source/pwm_oscillator.rb', line 6

def modulation_frequency
  @modulation_frequency
end

Instance Method Details

#process(_input_buffer, num_frames, start_frame, _cache) ⇒ Object 



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# File 'lib/deftones/source/pwm_oscillator.rb', line 24

def process(_input_buffer, num_frames, start_frame, _cache)
  frequencies = @frequency.process(num_frames, start_frame)
  mod_frequencies = @modulation_frequency.process(num_frames, start_frame)
  mod_depths = @modulation_depth.process(num_frames, start_frame)
  detunes = @detune.process(num_frames, start_frame)

  Array.new(num_frames) do |index|
    current_time = (start_frame + index).to_f / context.sample_rate
    next 0.0 unless active_at?(current_time)

    width = @base_width + (Math.sin(2.0 * Math::PI * @modulation_phase) * mod_depths[index] * 0.5)
    duty = Deftones::DSP::Helpers.clamp(width, 0.05, 0.95)
    sample = @phase < duty ? 1.0 : -1.0

    frequency = frequencies[index] * (2.0**(detunes[index].to_f / 1200.0))
    @phase = (@phase + (frequency / context.sample_rate)) % 1.0
    @modulation_phase = (@modulation_phase + (mod_frequencies[index] / context.sample_rate)) % 1.0
    sample
  end
end