PointerLockControls

PointerLockControls is a JavaScript API that allows web applications to gain exclusive control over the mouse pointer. This enables immersive experiences, particularly in 3D applications like games, where the cursor is typically hidden and its movement is used to control the camera.

When PointerLockControls is activated, the mouse cursor is confined to the browser window and its movement is no longer constrained by the viewport. Instead, the browser reports deltas in pointer movement, allowing developers to precisely map these changes to camera rotation or other in-game actions. This prevents the cursor from leaving the window and appearing on other applications or the desktop, which is crucial for uninterrupted gameplay.

To use PointerLockControls, a web application must first request pointer lock from the user. This is typically done via a user interaction, such as clicking a button or the canvas element. Once granted, the application can start capturing pointer movement events. Releasing pointer lock can be done programmatically or by the user pressing the Escape key.

The API provides methods to request and exit lock, and it emits events to notify the application when pointer lock is acquired or released. It is a fundamental tool for creating interactive and engaging web-based experiences that require precise and continuous control over user input. While not a standard part of core JavaScript, it is widely supported in modern web browsers.