Basic audio generation

sound.js

// Built from Mohit Cheppudira's sine wave generator - http://0xfe.blogspot.com
// Modified by Murat Ayfer - http://muratayfer.com

soundWave = function(context) {
    // xs is a list of x (time) values, one per wave.
    // time is not represented as synchronized clicks or milliseconds, its passing is freq dependent
    // so that's why we keep a value per each wave.
    this.xs = [];
    this.counter = 0;
    this.context = context;
    this.sampleRate = this.context.sampleRate; // 44100 by default
    this.sampleRateMillisecond = this.sampleRate / 1000;
    this.playing = false;


    this.node = context.createJavaScriptNode(1024, 1, 2);

    var that = this;
    this.node.onaudioprocess = function(e) { that.process(e) };
}

soundWave.prototype.process = function(e) {
    // Get a reference to the output buffer and fill it up.
    var channels = [ e.outputBuffer.getChannelData(0), e.outputBuffer.getChannelData(1) ];
    var buffer_size = channels[0].length;
    var num_channels = channels.length;

    var amplitude = 0;

    for (var i = 0; i < buffer_size; i++) {

        y = Math.sin((this.counter) * Math.PI * 2 * 440 / this.sampleRate);

        if(amplitude = 0) {
            amplitude = 1;
        } else {
            amplitude = 0;
        }


        for(var k = 0; k < num_channels; k++) {
            channels[k][i] = y;
        }
        this.counter += 1;
    }
}

soundWave.prototype.play = function() {
    this.node.connect(this.context.destination);
    this.playing = true;
}

soundWave.prototype.pause = function() {
    this.playing = false;
}

var audio = new AudioContext();
var wave = new soundWave(audio);

wave.play();