Added image zoom module

Gruntfile.js

@@ -68,6 +68,7 @@ module.exports = function(grunt) {
           'inline',
           'ajax',
           'image',
+          'zoom',
           'iframe',
           'gallery',
           'retina',

src/js/zoom.js

@@ -0,0 +1,181 @@
+var hasMozTransform,
+	getHasMozTransform = function() {
+		if(hasMozTransform === undefined) {
+			hasMozTransform = document.createElement('p').style.MozTransform !== undefined;
+		}
+		return hasMozTransform;		
+	};
+
+$.magnificPopup.registerModule('zoom', {
+
+	options: {
+		enabled: false,
+		easing: 'ease-in-out',
+		duration: 300,
+		opener: function(element) {
+			return element.is('img') ? element : element.find('img');
+		}
+	},
+
+	proto: {
+
+		initZoom: function() {
+			var zoomSt = mfp.st.zoom,
+				ns = '.zoom';
+
+			if(!zoomSt.enabled || !mfp.supportsTransition) {
+				return;
+			}
+
+			var duration = zoomSt.duration,
+				getElToAnimate = function(image) {
+					var newImg = image.clone().removeAttr('style').removeAttr('class').addClass('mfp-animated-image'),
+						transition = 'all '+(zoomSt.duration/1000)+'s ' + zoomSt.easing,
+						cssObj = {
+							position: 'fixed',
+	    					zIndex: 9999,
+	    					left: 0,
+	    					top: 0,
+	    					'-webkit-backface-visibility': 'hidden'
+						},
+						t = 'transition';
+
+					cssObj['-webkit'+t] = cssObj['-moz'+t] = cssObj['-o'+t] = cssObj[t] = transition;
+
+					newImg.css(cssObj);
+					return newImg
+				},
+				showMainContent = function() {
+					mfp.content.css('visibility', 'visible');
+				},
+				openTimeout,
+				animatedImg;
+
+			_mfpOn('BuildControls'+ns, function() {
+				if(mfp._allowZoom()) {
+
+					clearTimeout(openTimeout);
+					mfp.content.css('visibility', 'hidden');
+
+					// Basically, all code below does is clones existing image, puts in on top of the current one and animated it
+
+					image = mfp._getItemToZoom();
+
+					if(!image) {
+						showMainContent();
+						return;
+					}
+
+					animatedImg = getElToAnimate(image); 
+
+					animatedImg.css( mfp._getOffset() );
+
+					mfp.wrap.append(animatedImg);
+
+					openTimeout = setTimeout(function() {
+						animatedImg.css( mfp._getOffset( true ) );
+						openTimeout = setTimeout(function() {
+
+							showMainContent();
+
+							setTimeout(function() {
+								animatedImg.remove();
+								image = animatedImg = null;
+								_mfpTrigger('ZoomAnimationEnded');
+							}, 16); // avoid blink when switching images 
+
+						}, duration); // this timeout equals animation duration
+
+					}, 16); // by adding this timeout we avoid short glitch at the beginning of animation
+
+
+					// Lots of timeouts...
+				}
+			});
+			_mfpOn(BEFORE_CLOSE_EVENT+ns, function() {
+				if(mfp._allowZoom()) {
+
+					clearTimeout(openTimeout);
+
+					mfp.st.removalDelay = duration;
+
+					if(!image) {
+						image = mfp._getItemToZoom();
+						if(!image) {
+							return;
+						}
+						animatedImg = getElToAnimate(image);
+					}
+
+
+					animatedImg.css( mfp._getOffset(true) );
+					mfp.wrap.append(animatedImg);
+					mfp.content.css('visibility', 'hidden');
+
+					setTimeout(function() {
+						animatedImg.css( mfp._getOffset() );
+					}, 16);
+				}
+
+			});
+
+			_mfpOn(CLOSE_EVENT+ns, function() {
+				if(mfp._allowZoom()) {
+					showMainContent();
+					if(animatedImg) {
+						animatedImg.remove();
+					}
+				}	
+			});
+		},
+
+		_allowZoom: function() {
+			return mfp.currItem.type === 'image';
+		},
+
+		_getItemToZoom: function() {
+			if(mfp.currItem.hasSize) {
+				return mfp.currItem.img;
+			} else {
+				return false;
+			}
+		},
+
+		// Get element postion relative to viewport
+		_getOffset: function(isLarge) {
+			var el;
+			if(isLarge) {
+				el = mfp.currItem.img;
+			} else {
+				el = mfp.st.zoom.opener(mfp.currItem.el || mfp.currItem);
+			}
+
+			var offset = el.offset();
+			var paddingTop = parseInt(el.css('padding-top'),10);
+			var paddingBottom = parseInt(el.css('padding-bottom'),10);
+			offset.top -= ( $(window).scrollTop() - paddingTop );
+
+
+			/*
+			
+			Animating left + top + width/height looks glitchy in Firefox, but perfect in Chrome. And vice-versa.
+
+			 */
+			var obj = {
+				width: el.width(),
+				height: el.height() - paddingBottom - paddingTop
+			};
+
+			// I hate to do this, but there is no another option
+			if( getHasMozTransform() ) {
+				obj['-moz-transform'] = obj['transform'] = 'translate(' + offset.left + 'px,' + offset.top + 'px)';
+			} else {
+				obj.left = offset.left;
+				obj.top = offset.top;
+			}
+			return obj;
+		},
+
+	}
+});
+