A mobile VR compatible class to use with Babylon.js

MobileVRCamera.js

var MobileVRCamera = (function() {

	var mobileVR = function(position, scene) {
		BABYLON.OculusCamera.call(this, "MobileVR Component", position, scene);

		this.vrEnabled = false;
		this.screenOrientation = 0;
		this.deviceOrientation = {
			alpha: 0,
			beta: 0,
			gamma: 0
		};

		this._onOrientationEvent = this._onOrientationEvent.bind(this);
	};

	mobileVR.prototype = Object.create(BABYLON.OculusCamera.prototype);

	mobileVR.prototype.attachControl = function(element, noPreventDefault) {
		BABYLON.OculusCamera.prototype.attachControl.call(this, element, noPreventDefault);
		this._startVR();
	};

	mobileVR.prototype.detachControl = function(element) {
		BABYLON.OculusCamera.prototype.detachControl.call(this, element);
		this.vrEnabled = false;
	};

	mobileVR.prototype._onOrientationEvent = function(event) {
		this.deviceOrientation.alpha = +event.alpha | 0;
		this.deviceOrientation.beta = +event.beta | 0;
		this.deviceOrientation.gamma = +event.gamma | 0;
	};

	mobileVR.prototype._startVR = function() {
		var _this = this,
			alpha = 0,
			beta = 0,
			gamma = 0;

		var deg2Rad = function (degrees) {
			return degrees * Math.PI / 180.0;
		};

		this.vrEnabled = true;

		(function loop() {
			if (_this.vrEnabled) {
				requestAnimationFrame(loop);
			}

			alpha = deg2Rad(_this.deviceOrientation.alpha); // Y
			beta = deg2Rad(_this.deviceOrientation.beta); // Z

			// Fix rotation.
			gamma = _this.deviceOrientation.gamma; // X

			if (gamma < 0)
				gamma = deg2Rad(90 + gamma);
			else {
				gamma = deg2Rad(270 - gamma);
			}

			_this.rotation.x = gamma;
			_this.rotation.y = -alpha;
			_this.rotation.z = beta;

			// Update the camera
			_this._update();
		})();
	};

	return mobileVR;
})();