Class: Wavify::DSP::LFO

Inherits:
Object
  • Object
show all
Defined in:
lib/wavify/dsp/lfo.rb,
sig/dsp.rbs

Overview

Low frequency oscillator for modulation sources.

Constant Summary collapse

WAVEFORMS = 
%i[sine triangle square sawtooth].freeze

Instance Method Summary collapse

Constructor Details

#initialize(rate:, sample_rate:, waveform: :sine, phase: 0.0) ⇒ LFO

Returns a new instance of LFO.

Parameters:

  • rate: (Numeric)
  • sample_rate: (Numeric)
  • waveform: (Symbol) (defaults to: :sine)
  • phase: (Numeric) (defaults to: 0.0) 


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# File 'lib/wavify/dsp/lfo.rb', line 9

def initialize(rate:, sample_rate:, waveform: :sine, phase: 0.0)
  @rate = validate_positive!(rate, :rate)
  @sample_rate = validate_positive!(sample_rate, :sample_rate)
  @waveform = validate_waveform!(waveform)
  @initial_phase = phase.to_f % 1.0
  reset
end

Instance Method Details

#next_value ⇒ Float

Returns:

  • (Float) 


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# File 'lib/wavify/dsp/lfo.rb', line 17

def next_value
  value = value_at_phase(@phase)
  @phase = (@phase + (@rate / @sample_rate)) % 1.0
  value
end

#reset ⇒ LFO

Returns:



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# File 'lib/wavify/dsp/lfo.rb', line 27

def reset
  @phase = @initial_phase
  self
end

#value_at(offset = 0.0) ⇒ Float

Parameters:

  • offset (Numeric) (defaults to: 0.0)

Returns:

  • (Float) 


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# File 'lib/wavify/dsp/lfo.rb', line 23

def value_at(offset = 0.0)
  value_at_phase((@phase + offset.to_f) % 1.0)
end