Implemented standalone detect zoom file

detect-zoom-full.js

@@ -0,0 +1,164 @@
+
+/* Detect-zoom
+ * -----------
+ * Cross Browser Zoom and Pixel Ratio Detector
+ * Version 1.0.4 | Apr 1 2013
+ * dual-licensed under the WTFPL and MIT license
+ * Maintained by https://github/tombigel
+ * Original developer https://github.com/yonran
+ */
+
+//AMD and CommonJS initialization copied from https://github.com/zohararad/audio5js
+(function (root, ns, factory) {
+	"use strict";
+
+	if (typeof (module) !== 'undefined' && module.exports) { // CommonJS
+		module.exports = factory(ns, root);
+	} else if (typeof (define) === 'function' && define.amd) { // AMD
+		define("detect-zoom", function () {
+			return factory(ns, root);
+		});
+	} else {
+		root[ns] = factory(ns, root);
+	}
+
+}(window, 'detectZoom', function () {
+
+	/**
+	 * Use devicePixelRatio if supported by the browser
+	 * @return {Number}
+	 * @private
+	 */
+	const devicePixelRatio = () => {
+		return window.devicePixelRatio || 1;
+    };
+
+    const isRetinaDevice = () => {
+        return devicePixelRatio() > 1
+    }
+	/**
+	 * Fallback function to set default values
+	 * @return {Object}
+	 * @private
+	 */
+	const fallback = () => ({
+        zoom: 1,
+        devicePxPerCssPx: 1
+    })
+
+    const commonZoomMethod = (screenResolution, windowWidth) => {
+        const zoom = Math.round(((screenResolution) / windowWidth)*100) / 100;
+		return {
+			zoom: zoom * 100,
+			devicePxPerCssPx: zoom * devicePixelRatio()
+		};
+    }
+
+
+	/**
+	 * For chrome
+	 * @return {Object}
+	 */
+	const chrome = () => commonZoomMethod(window.outerWidth, window.innerWidth);
+
+	/**
+	 * For safari (same as chrome)
+	 * @return {Object}
+	 */
+	const safari = () => commonZoomMethod(window.outerWidth, window.innerWidth);
+
+	/**
+	 * Firefox 18.x
+	 * Mozilla added support for devicePixelRatio to Firefox 18,
+	 * but it is affected by the zoom level, and by retina display 
+     * so we need to check retina displays and treat it as normal display
+	 * @return {Object}
+	 * @private
+	 */
+    const firefox18 = function () {
+        const pixelRatio = isRetinaDevice ? devicePixelRatio() / 2 : devicePixelRatio()
+        const screenWidthResolution = screen.width * pixelRatio;
+		return commonZoomMethod(screenWidthResolution, window.innerWidth);
+	};
+
+
+
+	/**
+	 * Generate detection function
+	 * @private
+	 */
+	const detectFunction = (function () {
+        let func = fallback;
+
+        const isSafari =
+            /Safari/.test(navigator.userAgent) &&
+            /Apple Computer/.test(navigator.vendor);
+
+		//chrome
+		if(!!window.chrome && !(!!window.opera || navigator.userAgent.indexOf(' Opera') >= 0)){
+			func = chrome;
+		}
+		//safari
+		else if(Object.prototype.toString.call(window.HTMLElement).indexOf('Constructor') > 0 || isSafari){
+			func = safari;
+		}	
+		//WebKit
+		else if ('webkitRequestAnimationFrame' in window) {
+			func = webkit;
+		}
+		//Last one is Firefox
+		//FF 18.x
+		else if (window.devicePixelRatio) {
+			func = firefox18;
+		}
+
+		return func;
+	}());
+
+
+	return ({
+		/**
+		 * Ratios.zoom shorthand
+		 * @return {Number} Zoom level
+		 */
+		zoom: function () {
+			return detectFunction().zoom;
+		},
+
+		/**
+		 * Ratios.devicePxPerCssPx shorthand
+		 * @return {Number} devicePxPerCssPx level
+		 */
+		device: function () {
+			return detectFunction().devicePxPerCssPx;
+		}
+	});
+}));
+
+//-----------------------
+// debouncing plugin by Paul Irish https://www.paulirish.com/2009/throttled-smartresize-jquery-event-handler/
+//-----------------------
+(function($,sr){
+	const debounce = function (func, threshold, execAsap) {
+		let timeout;
+
+		return function debounced () {
+			const obj = this, args = arguments;
+			function delayed () {
+				if (!execAsap)
+					func.apply(obj, args);
+				timeout = null;
+			};
+
+			if (timeout)
+				clearTimeout(timeout);
+			else if (execAsap)
+				func.apply(obj, args);
+
+			timeout = setTimeout(delayed, threshold || 100);
+		};
+	}
+	// smartresize
+	jQuery.fn[sr] = function(fn){  return fn ? this.on('resize', debounce(fn)) : this.trigger(sr); };
+
+})(jQuery,'smartresize');