genish.js/js/peek.js

gen~ in js

const gen  = require('./gen.js'),
      dataUgen = require('./data.js')

let proto = {
  basename:'peek',

  gen() {
    let genName = 'gen.' + this.name,
        inputs = gen.getInputs( this ),
        out, functionBody, next, lengthIsLog2, idx
    
    idx = inputs[1]
    lengthIsLog2 = (Math.log2( this.data.buffer.length ) | 0)  === Math.log2( this.data.buffer.length )

    if( this.mode !== 'simple' ) {

    functionBody = `  var ${this.name}_dataIdx  = ${idx}, 
      ${this.name}_phase = ${this.mode === 'samples' ? inputs[0] : inputs[0] + ' * ' + (this.data.buffer.length) }, 
      ${this.name}_index = ${this.name}_phase | 0,\n`

    if( this.boundmode === 'wrap' ) {
      next = lengthIsLog2 ?
      `( ${this.name}_index + 1 ) & (${this.data.buffer.length} - 1)` :
      `${this.name}_index + 1 >= ${this.data.buffer.length} ? ${this.name}_index + 1 - ${this.data.buffer.length} : ${this.name}_index + 1`
    }else if( this.boundmode === 'clamp' ) {
      next = 
        `${this.name}_index + 1 >= ${this.data.buffer.length - 1} ? ${this.data.buffer.length - 1} : ${this.name}_index + 1`
    } else if( this.boundmode === 'fold' || this.boundmode === 'mirror' ) {
      next = 
        `${this.name}_index + 1 >= ${this.data.buffer.length - 1} ? ${this.name}_index - ${this.data.buffer.length - 1} : ${this.name}_index + 1`
    }else{
       next = 
      `${this.name}_index + 1`     
    }

    if( this.interp === 'linear' ) {      
    functionBody += `      ${this.name}_frac  = ${this.name}_phase - ${this.name}_index,
      ${this.name}_base  = memory[ ${this.name}_dataIdx +  ${this.name}_index ],
      ${this.name}_next  = ${next},`
      
      if( this.boundmode === 'ignore' ) {
        functionBody += `
      ${this.name}_out   = ${this.name}_index >= ${this.data.buffer.length - 1} || ${this.name}_index < 0 ? 0 : ${this.name}_base + ${this.name}_frac * ( memory[ ${this.name}_dataIdx + ${this.name}_next ] - ${this.name}_base )\n\n`
      }else{
        functionBody += `
      ${this.name}_out   = ${this.name}_base + ${this.name}_frac * ( memory[ ${this.name}_dataIdx + ${this.name}_next ] - ${this.name}_base )\n\n`
      }
    }else{
      functionBody += `      ${this.name}_out = memory[ ${this.name}_dataIdx + ${this.name}_index ]\n\n`
    }

    } else { // mode is simple
      functionBody = `memory[ ${idx} + ${ inputs[0] } ]`
      
      return functionBody
    }

    gen.memo[ this.name ] = this.name + '_out'

    return [ this.name+'_out', functionBody ]
  },

  defaults : { channels:1, mode:'phase', interp:'linear', boundmode:'wrap' }
}

module.exports = ( input_data, index=0, properties ) => {
  let ugen = Object.create( proto )

  //console.log( dataUgen, gen.data )

  // XXX why is dataUgen not the actual function? some type of browserify nonsense...
  const finalData = typeof input_data.basename === 'undefined' ? gen.lib.data( input_data ) : input_data

  Object.assign( ugen, 
    { 
      'data':     finalData,
      dataName:   finalData.name,
      uid:        gen.getUID(),
      inputs:     [ index, finalData ],
    },
    proto.defaults,
    properties 
  )
  
  ugen.name = ugen.basename + ugen.uid

  return ugen
}