three.js/examples/js/controls/DeviceOrientationControls.js

( function () {

	/**
 * W3C Device Orientation control (http://w3c.github.io/deviceorientation/spec-source-orientation.html)
 */

	var DeviceOrientationControls = function ( object ) {

		if ( window.isSecureContext === false ) {

			console.error( 'THREE.DeviceOrientationControls: DeviceOrientationEvent is only available in secure contexts (https)' );

		}

		var scope = this;
		var changeEvent = {
			type: 'change'
		};
		var EPS = 0.000001;
		this.object = object;
		this.object.rotation.reorder( 'YXZ' );
		this.enabled = true;
		this.deviceOrientation = {};
		this.screenOrientation = 0;
		this.alphaOffset = 0; // radians

		var onDeviceOrientationChangeEvent = function ( event ) {

			scope.deviceOrientation = event;

		};

		var onScreenOrientationChangeEvent = function () {

			scope.screenOrientation = window.orientation || 0;

		}; // The angles alpha, beta and gamma form a set of intrinsic Tait-Bryan angles of type Z-X'-Y''


		var setObjectQuaternion = function () {

			var zee = new THREE.Vector3( 0, 0, 1 );
			var euler = new THREE.Euler();
			var q0 = new THREE.Quaternion();
			var q1 = new THREE.Quaternion( - Math.sqrt( 0.5 ), 0, 0, Math.sqrt( 0.5 ) ); // - PI/2 around the x-axis

			return function ( quaternion, alpha, beta, gamma, orient ) {

				euler.set( beta, alpha, - gamma, 'YXZ' ); // 'ZXY' for the device, but 'YXZ' for us

				quaternion.setFromEuler( euler ); // orient the device

				quaternion.multiply( q1 ); // camera looks out the back of the device, not the top

				quaternion.multiply( q0.setFromAxisAngle( zee, - orient ) ); // adjust for screen orientation

			};

		}();

		this.connect = function () {

			onScreenOrientationChangeEvent(); // run once on load
			// iOS 13+

			if ( window.DeviceOrientationEvent !== undefined && typeof window.DeviceOrientationEvent.requestPermission === 'function' ) {

				window.DeviceOrientationEvent.requestPermission().then( function ( response ) {

					if ( response == 'granted' ) {

						window.addEventListener( 'orientationchange', onScreenOrientationChangeEvent );
						window.addEventListener( 'deviceorientation', onDeviceOrientationChangeEvent );

					}

				} ).catch( function ( error ) {

					console.error( 'THREE.DeviceOrientationControls: Unable to use DeviceOrientation API:', error );

				} );

			} else {

				window.addEventListener( 'orientationchange', onScreenOrientationChangeEvent );
				window.addEventListener( 'deviceorientation', onDeviceOrientationChangeEvent );

			}

			scope.enabled = true;

		};

		this.disconnect = function () {

			window.removeEventListener( 'orientationchange', onScreenOrientationChangeEvent );
			window.removeEventListener( 'deviceorientation', onDeviceOrientationChangeEvent );
			scope.enabled = false;

		};

		this.update = function () {

			var lastQuaternion = new THREE.Quaternion();
			return function () {

				if ( scope.enabled === false ) return;
				var device = scope.deviceOrientation;

				if ( device ) {

					var alpha = device.alpha ? THREE.MathUtils.degToRad( device.alpha ) + scope.alphaOffset : 0; // Z

					var beta = device.beta ? THREE.MathUtils.degToRad( device.beta ) : 0; // X'

					var gamma = device.gamma ? THREE.MathUtils.degToRad( device.gamma ) : 0; // Y''

					var orient = scope.screenOrientation ? THREE.MathUtils.degToRad( scope.screenOrientation ) : 0; // O

					setObjectQuaternion( scope.object.quaternion, alpha, beta, gamma, orient );

					if ( 8 * ( 1 - lastQuaternion.dot( scope.object.quaternion ) ) > EPS ) {

						lastQuaternion.copy( scope.object.quaternion );
						scope.dispatchEvent( changeEvent );

					}

				}

			};

		}();

		this.dispose = function () {

			scope.disconnect();

		};

		this.connect();

	};

	DeviceOrientationControls.prototype = Object.create( THREE.EventDispatcher.prototype );
	DeviceOrientationControls.prototype.constructor = DeviceOrientationControls;

	THREE.DeviceOrientationControls = DeviceOrientationControls;

} )();