hypotheticalOperationArray.coffee

cppOperations = [
  [ 'sine', '466.667', '88200']
  [ 'volume', '0.5', '0', '88200']
  [ 'fade in' '0', '88200' ]
  [ 'ramp', '0', '30', '88170', '88200' ]
]

Nt.do cppOPerations

Nt.coffee

Nt = require './build/Release/NtCpp'
{buildFile} = require '../reallyOldNt/noitech'

buildFile 'pointerTest1.wav', [Nt.sineGenerate 466.667, 88200]

Nt.cpp

#include <nan.h>
#include <stdio.h>
#include <stdlib.h>
#include <iostream>

// For sine function
#include <math.h>

#include "./generate/sineGenerate.h"

using namespace v8;
using v8::String;

// Arguments are:
// frequency duration
NAN_METHOD(sineGenerate){
  NanScope();

  int sustain = args[1]->Uint32Value();
  double frequency = args[0]->NumberValue();
  frequency /= 44100;

  short * audio = new short[sustain];
  int confirmation = sineGenerate1(frequency, sustain, audio);

  Local<Array> output = NanNew<Array>(sustain);

  int sampleIndex = 0;
  while (sampleIndex < sustain){
    short sample = audio[sampleIndex];
    output->Set(sampleIndex, NanNew(sample));
    sampleIndex++;
  }

  NanReturnValue(output);
}

void Init(Handle<Object> exports){
  exports->Set(NanNew("sineGenerate"),
    NanNew<FunctionTemplate>(sineGenerate)->GetFunction());
}

NODE_MODULE(NtCpp, Init);

sineGenerate.h

int sineGenerate1 (double frequency, const int sustain, short * audio){

  double pi = 3.14159;
  int maxAmplitude = 32767;

  int outputIndex = 0;
  while (outputIndex < sustain){
    short sample = maxAmplitude * sin(pi * frequency * outputIndex * 2);
    *(audio + outputIndex) = sample;
    outputIndex++;
  }

  return outputIndex; 
}