https://www.turismofvg.it/TFVGB/Content/LIBs/JS_base/jquery.myimgs…?bundleVirtualPath=~%2Fbundles%2Fjs_booking

1/**
2    MyImgScale v0.2
3 
4    MyImgScale is a jQuery plugin to scale images to fit or fill their parent container.
5    Note: The parent container of the image must have a defined height and width in CSS.
6    
7    It is actually a merger/improvement from two existing plugins:
8     1) Image Scale v1.0 by Kelly Meath (http://imgscale.kjmeath.com/), and
9     2) CJ Object Scaler v3.0.0 by Doug Jones (http://www.cjboco.com/projects.cfm/project/cj-object-scaler/)
10
11    The reasons for this merger are:
12    . CJ Object Scaler has a conciser image resizing algorithm while Image Scale has a clearer layout.
13    . CJ Object Scaler has an overflow issue, ie. the image scaled is not confined in parent container.
14    . Both have the wrong calculation when parent container is invisible.
15    
16    If the parent container has padding, the scaled image might still cross boundary.
17    One of the solutions is to insert a wrapper div with the same height and width as the parent container, eg:
18    <div id="parent" style="height: 120px; width: 90px; padding: 10px">
19      <div id="interimWrapper" style="height: 120px; width: 90px;">
20        <img src="<Your img link here>" />
21      </div>
22    </div>
23    I prefer to do this in application rather than in plugin as it is somewhat obtrusive.
24    
25    Web: https://bitbucket.org/marshalking/myimgscale
26    Updated: Apr 15, 2011 by Marshal
27    
28    -----------------------------------------------------------------------
29    MIT License
30
31    Copyright (c) 2011 Doug Jones, Kelly Meath, Marshal
32
33    Permission is hereby granted, free of charge, to any person obtaining
34    a copy of this software and associated documentation files (the
35    "Software"), to deal in the Software without restriction, including
36    without limitation the rights to use, copy, modify, merge, publish,
37    distribute, sublicense, and/or sell copies of the Software, and to
38    permit persons to whom the Software is furnished to do so, subject to
39    the following conditions:
40
41    The above copyright notice and this permission notice shall be
42    included in all copies or substantial portions of the Software.
43
44    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
45    EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
46    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
47    NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
48    LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
49    OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
50    WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
51 */
52
53(function($) {
54    $.fn.scaleImage = function(options) {
55        var opts = $.extend({parent: false, scale: 'fill', center: true, fade: 0}, options); // merge default options with user's
56
57        return this.each(function() {
58            var $img = $(this);
59            var $parent = opts.parent ? $img.parents(opts.parent) : $img.parent(); // if not supplied, use default direct parent
60            $parent.css({opacity: 0, overflow: 'hidden'}); // keep the img inside boundaries
61            
62            if ($parent.length > 0) {
63                $img.removeAttr('height').removeAttr('width');
64                if (this.complete) { // img already loaded/cached
65                    scale($img, $parent);
66                } else {
67                    $img.load(function() {
68                        scale($img, $parent);
69                    });
70                }
71            }
72        });
73        
74        function scale($img, $parent) {
75            var imgSize = getOriginalImgSize($img),
76                imgW = imgSize.width,
77                imgH = imgSize.height,
78                destW = $parent.width(),
79                destH = $parent.height(),
80                borderW = parseInt($img.css("borderLeftWidth"), 10) + parseInt($img.css("borderRightWidth"), 10),
81                borderH = parseInt($img.css("borderTopWidth"), 10) + parseInt($img.css("borderBottomWidth"), 10),
82                ratioX, ratioY, ratio, newWidth, newHeight;
83            
84            if (destH === 0 || destW === 0) { // parent is invisible, eg. display: none
85                var parentSize = getHiddenElemSize($parent);
86                destW = parentSize.width;
87                destH = parentSize.height;
88            }
89            
90            // check for valid border values. IE takes in account border size when calculating width/height so just set to 0
91            borderW = isNaN(borderW) ? 0 : borderW;
92            borderH = isNaN(borderH) ? 0 : borderH;
93            
94            // calculate scale ratios
95            ratioX = destW / imgW;
96            ratioY = destH / imgH;
97
98            // Determine which algorithm to use
99            if (opts.scale === "fit") {
100                ratio = ratioX < ratioY ? ratioX : ratioY;
101            } else if (opts.scale === "fill") {
102                ratio = ratioX > ratioY ? ratioX : ratioY;
103            }
104
105            // calculate our new image dimensions
106            newWidth = parseInt(imgW * ratio, 10) - borderW;
107            newHeight = parseInt(imgH * ratio, 10) - borderH;
108            
109            // Set new dimensions to both css and img's attributes
110            $img.css({
111                "width": newWidth,
112                "height": newHeight
113            }).attr({
114                "width": newWidth,
115                "height": newHeight
116            });
117            
118            if (opts.center) { // set offset if center is true
119                $img.css("margin-left", Math.floor((destW - newWidth) / 2));
120                $img.css("margin-top", Math.floor((destH - newHeight) / 2));
121            }
122        
123            if (opts.fade > 0) { // fade-in effect
124                $parent.animate({opacity: 1}, opts.fade);
125            } else {
126                $parent.css("opacity", 1);
127            }
128        }
129
130        /**
131         * To calculate the correct scale ratio, we need the image's original size rather than some preset values,
132         * which were set either manually in code or automatically by browser.
133         * Thanks FDisk for the solution:
134         * http://stackoverflow.com/questions/318630/get-real-image-width-and-height-with-javascript-in-safari-chrome
135         */
136        function getOriginalImgSize($img) {
137            var t = new Image();
138            t.src = $img.attr("src");
139            return {width: t.width, height: t.height};
140        }
141        
142        /**
143         * If the element is invisible, jQeury .height() and .width() return 0 in IE.
144         * This function returns the hidden element's correct width and height.
145         * Thanks elliotlarson for the solution:
146         * http://stackoverflow.com/questions/2345784/jquery-get-height-of-hidden-element-in-jquery-1-4-2
147         */
148        function getHiddenElemSize(element) {
149            var copy = element.clone().css({visibility: 'hidden', display: 'block', position: 'absolute'});
150            $("body").append(copy);
151            var size = {width: copy.width(), height: copy.height()};
152            copy.remove();
153            return size;
154        }
155    };
156})(jQuery);