gibberish-dsp/js/fx/ringMod.js

Gibberish is designed to be an optimized API for audio synthesis using per-sample techniques.

let g = require( 'genish.js' ),
    effect = require( './effect.js' )

module.exports = function( Gibberish ) {
 
let RingMod = inputProps => {
  let props   = Object.assign( {}, RingMod.defaults, effect.defaults, inputProps ),
      ringMod = Object.create( effect ),
      out

  ringMod.__createGraph = function() {
    let isStereo = false
    if( out === undefined ) {
      isStereo = typeof props.input.isStereo !== 'undefined' ? props.input.isStereo : false 
    }else{
      isStereo = out.input.isStereo
      out.isStereo = isStereo
    }    

    const input = g.in( 'input' ),
          inputGain = g.in( 'inputGain' ),
          frequency = g.in( 'frequency' ),
          gain = g.in( 'gain' ),
          mix = g.in( 'mix' )
    
    const leftInput = isStereo ? g.mul( input[0], inputGain ) : g.mul( input, inputGain ),
          sine = g.mul( g.cycle( frequency ), gain )
   
    const left = g.add( g.mul( leftInput, g.sub( 1, mix )), g.mul( g.mul( leftInput, sine ), mix ) ) 
        
    if( isStereo === true ) {
      const rightInput = g.mul( input[1], inputGain ),
            right = g.add( g.mul( rightInput, g.sub( 1, mix )), g.mul( g.mul( rightInput, sine ), mix ) ) 
      
      ringMod.graph = [ left, right ]
    }else{
      ringMod.graph = left
    }
  }

  ringMod.__createGraph() 
  ringMod.__requiresRecompilation = [ 'input' ]

  out = Gibberish.factory( 
    ringMod,
    ringMod.graph, 
    [ 'fx','ringMod'], 
    props 
  )
  
  return out 
}

RingMod.defaults = {
  input:0,
  frequency:220,
  gain: 1, 
  mix:1
}

return RingMod

}