gameController.js

A JavaScript library that lets you handle, configure, and use gamepad and controllers on a browser.

Getting started

GameController.js is a lightweight library (~6KB) that uses JavaScript and the standard Gamepad API, and does not have any plugin/library dependencies.

Installation

From npm:

npm i gamecontroller.js

From yarn:

yarn add gamecontroller.js

Directly into your webpage (check latest release on github):

<script src="./gamecontroller.min.js"></script>

Usage

After importing the library into your webpage/project, gameControl will be available to use. This object comes with a series of properties and methods that will allow to handle the different gamepads connected to the computer.

The connected gamepads will be stored in a list of gamepad objects in gameControl. This gamepad object is not the default one returned by the browser but a higher-level interface to interact with it and simplify its usability.

Once the file is imported into the project, the object gameControl will be available and ready to be used.

gameControl.on('connect', function(gamepad) {
  gamepad.on('up', moveCharacterUp);
});

Visit the Wiki for a full list of the properties, methods and events of these two objects.

Events for gameControl

For the object gameControl, events are associated using the .on() method:

gameControl.on('connect', gamepad => {
  console.log('A new gamepad was connected!');
});

Here is a list of the events that can be associated using .on():

Name	Description
`connect`	Triggered every time that a gamepad is connected to the browser. It returns an instance of the `gamepad` object described below.
`disconnect`	Triggered when a gamepad is disconnected from the browser.
`beforeCycle`	Triggered before the gamepads are checked for pressed buttons/joysticks movement (before those events are triggered).
`afterCycle`	Triggered after the gamepads are checked for pressed buttons/joysticks movement (after those events have been triggered).

Events for gamepad

The events for the gamepad objects work a little bit different. The event name, is the name of the button/direction that was activated (e.g. button0, up, etc.) And there are three functions that can be used to associate event handlers for them in different situations:

.on(): triggered every cycle, while the button/joystick is pressed/active.
.before(): triggered the first cycle that a button/joystick is pressed.
.after(): triggered the first cycle after a button/joystick stopped being pressed.

All three functions can be chained and allow two parameters: the first one is the button/direction that was activated, and the second parameter is the callback function. Example:

gamepad.on('button0',     () => { console.log('Button 0 still pressed...'); })
       .before('button0', () => { console.log('Button 0 pressed...');       })
       .after('button0',  () => { console.log('Button 0 was released';      });

To see the event flow and how the different events are lined-up and interact with each other, visit the Event Flow wikipage.

Thisus

These are the events that can be passed as first parameter to the event functions:

Name	Description
`button0`	Triggered when button 0 is pressed.
`button1`	Triggered when button 1 is pressed.
`button2`	Triggered when button 2 is pressed.
`button3`	Triggered when button 3 is pressed.
`button4`	Triggered when button 4 is pressed.
`button5`	Triggered when button 5 is pressed.
`button6`	Triggered when button 6 is pressed.
`button7`	Triggered when button 7 is pressed.
`button8`	Triggered when button 8 is pressed.
`button9`	Triggered when button 9 is pressed.
`button10`	Triggered when button 10 is pressed.
`button11`	Triggered when button 11 is pressed.
`button12`	Triggered when button 12 is pressed.
`button13`	Triggered when button 13 is pressed.
`button14`	Triggered when button 14 is pressed.
`button15`	Triggered when button 15 is pressed.
`button16`	Triggered when button 16 is pressed.
`up0`	Triggered when the first axe/joystick is moved up.
`down0`	Triggered when the first axe/joystick is moved down.
`right0`	Triggered when the first axe/joystick is moved right.
`left0`	Triggered when the first axe/joystick is moved left.
`up1`	Triggered when the second axe/joystick is moved up.
`down1`	Triggered when the second axe/joystick is moved down.
`right1`	Triggered when the second axe/joystick is moved right.
`left1`	Triggered when the second axe/joystick is moved left.
`start`	Triggered when Start button is pressed. This is an alias for event `button9`.
`select`	Triggered when Select button is pressed. This is an alias for event `button8`.
`power`	Triggered when Power button is pressed (e.g. the Xbox logo in an Xbox controller). This is an alias for event `button16`.
`l1`	Triggered when the left back button 1 is pressed. This is an alias for event `button4`.
`l2`	Triggered when left back button 2 is pressed. This is an alias for event `button6`.
`r1`	Triggered when right back button 1 is pressed. This is an alias for event `button5`.
`r2`	Triggered when right back button 2 is pressed. This is an alias for event `button7`.
`up`	Triggered when the main/first axe/joystick is moved up. This is an alias for event `up0`.
`down`	Triggered when the main/first axe/joystick is moved down. This is an alias for event `down0`.
`right`	Triggered when the main/first axe/joystick is moved right. This is an alias for event `right0`.
`left`	Triggered when the main/first axe/joystick is moved left. This is an alias for event `left0`.

These names are not arbitrary. They match the buttons and axes described in the W3C Gamepad API specicification:

Browser Support

Edge	Firefox	Chrome	Safari	Opera
12+	29+	25+	10.1+	24+

Examples

The examples folder contains different examples to showcase how to use the library:

Connectivity: shows how to detect if a gamepad was connected/disconnected.
Buttons and Joysticks: see how the buttons from your gamepad map to the default gamepad.
SNES Controller: replica of a SNES controller (based on a previous CodePen demo).
Alvanoid: small Arkanoid-based game (based on a previous CodePen demo).
Pong: multiplayer demo with the classic game Pong for 2 players on 2 gamepads.

alvaromontoro/gamecontroller.js