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<!DOCTYPE HTML>
<html>
<head>
  <title>Test WaveShaperNode with no curve</title>
  <script src="/tests/SimpleTest/SimpleTest.js"></script>
  <script type="text/javascript" src="webaudio.js"></script>
  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
</head>
<body>
<pre id="test">
<script class="testbody" type="text/javascript">

var gTest = {
  length: 4096,
  numberOfChannels: 1,
  createGraph(context) {
    var source = context.createBufferSource();
    source.buffer = this.buffer;

    var shaper = new WaveShaperNode(context);
    shaper.curve = this.curve;

    source.connect(shaper);

    source.start(0);
    return shaper;
  },
  createExpectedBuffers(context) {
    this.buffer = context.createBuffer(1, 4096, context.sampleRate);
    for (var i = 1; i < 4095; ++i) {
      this.buffer.getChannelData(0)[i] = 2 * (i / 4096) - 1;
    }
    // Two out of range values
    this.buffer.getChannelData(0)[0] = -2;
    this.buffer.getChannelData(0)[4095] = 2;

    this.curve = new Float32Array(2048);
    for (var i = 0; i < 2048; ++i) {
      this.curve[i] = Math.sin(100 * Math.PI * (i + 1) / context.sampleRate);
    }

    var expectedBuffer = context.createBuffer(1, 4096, context.sampleRate);
    for (var i = 1; i < 4095; ++i) {
      var input = this.buffer.getChannelData(0)[i];
      var index = Math.floor(this.curve.length * (input + 1) / 2);
      index = Math.max(0, Math.min(this.curve.length - 1, index));
      expectedBuffer.getChannelData(0)[i] = this.curve[index];
    }
    expectedBuffer.getChannelData(0)[0] = this.curve[0];
    expectedBuffer.getChannelData(0)[4095] = this.curve[2047];
    return expectedBuffer;
  },
};

runTest();

</script>
</pre>
</body>
</html>