BaseAudioContext: createPanner() method
=======================================

 The `createPanner()` method of the `BaseAudioContext`
 Interface is used to create a new `PannerNode`, which is used to
 spatialize an incoming audio stream in 3D space.

 The panner node is spatialized in relation to the AudioContext's
 `AudioListener` (defined by the `AudioContext.listener`
 attribute), which represents the position and orientation of the person listening to the
 audio.


**Note:** The `PannerNode()`
 constructor is the recommended way to create a `PannerNode`; see
 Creating an AudioNode.


Syntax
------


```js
createPanner()
```

### Parameters

None.

### Return value

A `PannerNode`.

Examples
--------

 In the following example, you can see an example of how the `createPanner()`
 method, `AudioListener` and `PannerNode` would be used to
 control audio spatialization. Generally you will define the position in 3D space that
 your audio listener and panner (source) occupy initially, and then update the position
 of one or both of these as the application is used. You might be moving a character
 around inside a game world for example, and wanting delivery of audio to change
 realistically as your character moves closer to or further away from a music player such
 as a stereo. In the example you can see this being controlled by the functions
 `moveRight()`, `moveLeft()`, etc., which set new values for the
 panner position via the `PositionPanner()` function.

 To see a complete implementation, check out our panner-node example
 (view the source code) — this demo transports you to the 2.5D "Room of metal", where you can
 play a track on a boom box and then walk around the boom box to see how the sound
 changes!

 Note how we have used some feature detection to either give the browser the newer
 property values (like `AudioListener.forwardX`) for setting position, etc.
 if it supports those, or older methods (like
 `AudioListener.setOrientation()`) if it still supports those but not the
 new properties.


```js
// set up listener and panner position information
const WIDTH = window.innerWidth;
const HEIGHT = window.innerHeight;

const xPos = Math.floor(WIDTH / 2);
const yPos = Math.floor(HEIGHT / 2);
const zPos = 295;

// define other variables

const audioCtx = new AudioContext();

const panner = audioCtx.createPanner();
panner.panningModel = "HRTF";
panner.distanceModel = "inverse";
panner.refDistance = 1;
panner.maxDistance = 10000;
panner.rolloffFactor = 1;
panner.coneInnerAngle = 360;
panner.coneOuterAngle = 0;
panner.coneOuterGain = 0;

if (panner.orientationX) {
  panner.orientationX.setValueAtTime(1, audioCtx.currentTime);
  panner.orientationY.setValueAtTime(0, audioCtx.currentTime);
  panner.orientationZ.setValueAtTime(0, audioCtx.currentTime);
} else {
  panner.setOrientation(1, 0, 0);
}

const listener = audioCtx.listener;

if (listener.forwardX) {
  listener.forwardX.setValueAtTime(0, audioCtx.currentTime);
  listener.forwardY.setValueAtTime(0, audioCtx.currentTime);
  listener.forwardZ.setValueAtTime(-1, audioCtx.currentTime);
  listener.upX.setValueAtTime(0, audioCtx.currentTime);
  listener.upY.setValueAtTime(1, audioCtx.currentTime);
  listener.upZ.setValueAtTime(0, audioCtx.currentTime);
} else {
  listener.setOrientation(0, 0, -1, 0, 1, 0);
}

let source;

const play = document.querySelector(".play");
const stop = document.querySelector(".stop");

const boomBox = document.querySelector(".boom-box");

const listenerData = document.querySelector(".listener-data");
const pannerData = document.querySelector(".panner-data");

leftBound = -xPos + 50;
rightBound = xPos - 50;

xIterator = WIDTH / 150;

// listener will always be in the same place for this demo

if (listener.positionX) {
  listener.positionX.setValueAtTime(xPos, audioCtx.currentTime);
  listener.positionY.setValueAtTime(yPos, audioCtx.currentTime);
  listener.positionZ.setValueAtTime(300, audioCtx.currentTime);
} else {
  listener.setPosition(xPos, yPos, 300);
}

listenerData.textContent = `Listener data: X ${xPos} Y ${yPos} Z 300`;

// panner will move as the boombox graphic moves around on the screen
function positionPanner() {
  if (panner.positionX) {
    panner.positionX.setValueAtTime(xPos, audioCtx.currentTime);
    panner.positionY.setValueAtTime(yPos, audioCtx.currentTime);
    panner.positionZ.setValueAtTime(zPos, audioCtx.currentTime);
  } else {
    panner.setPosition(xPos, yPos, zPos);
  }
  pannerData.textContent = `Panner data: X ${xPos} Y ${yPos} Z ${zPos}`;
}
```


**Note:** In terms of working out what position values to apply to the
 listener and panner, to make the sound appropriate to what the visuals are doing on
 screen, there is quite a bit of math involved, but you will soon get used to it with a
 bit of experimentation.


Specifications
--------------

| Specification |
| --- |
| Web Audio API # dom-baseaudiocontext-createpanner |

Browser compatibility
---------------------

BCD tables only load in the browser with JavaScript enabled. Enable JavaScript to view data.

See also
--------

* Using the Web Audio API