Current state

public/legacy/assets/plugins/visible/jquery.visible.js

@@ -0,0 +1,68 @@
+(function($){
+
+    /**
+     * Copyright 2012, Digital Fusion
+     * Licensed under the MIT license.
+     * http://teamdf.com/jquery-plugins/license/
+     *
+     * @author Sam Sehnert
+     * @desc A small plugin that checks whether elements are within
+     *       the user visible viewport of a web browser.
+     *       only accounts for vertical position, not horizontal.
+     */
+    var $w = $(window);
+    $.fn.visible = function(partial,hidden,direction){
+
+        if (this.length < 1)
+            return;
+
+        var $t        = this.length > 1 ? this.eq(0) : this,
+            t         = $t.get(0),
+            vpWidth   = $w.width(),
+            vpHeight  = $w.height(),
+            direction = (direction) ? direction : 'both',
+            clientSize = hidden === true ? t.offsetWidth * t.offsetHeight : true;
+
+        if (typeof t.getBoundingClientRect === 'function'){
+
+            // Use this native browser method, if available.
+            var rec = t.getBoundingClientRect(),
+                tViz = rec.top    >= 0 && rec.top    <  vpHeight,
+                bViz = rec.bottom >  0 && rec.bottom <= vpHeight,
+                lViz = rec.left   >= 0 && rec.left   <  vpWidth,
+                rViz = rec.right  >  0 && rec.right  <= vpWidth,
+                vVisible   = partial ? tViz || bViz : tViz && bViz,
+                hVisible   = partial ? lViz || lViz : lViz && rViz;
+
+            if(direction === 'both')
+                return clientSize && vVisible && hVisible;
+            else if(direction === 'vertical')
+                return clientSize && vVisible;
+            else if(direction === 'horizontal')
+                return clientSize && hVisible;
+        } else {
+
+            var viewTop         = $w.scrollTop(),
+                viewBottom      = viewTop + vpHeight,
+                viewLeft        = $w.scrollLeft(),
+                viewRight       = viewLeft + vpWidth,
+                offset          = $t.offset(),
+                _top            = offset.top,
+                _bottom         = _top + $t.height(),
+                _left           = offset.left,
+                _right          = _left + $t.width(),
+                compareTop      = partial === true ? _bottom : _top,
+                compareBottom   = partial === true ? _top : _bottom,
+                compareLeft     = partial === true ? _right : _left,
+                compareRight    = partial === true ? _left : _right;
+
+            if(direction === 'both')
+                return !!clientSize && ((compareBottom <= viewBottom) && (compareTop >= viewTop)) && ((compareRight <= viewRight) && (compareLeft >= viewLeft));
+            else if(direction === 'vertical')
+                return !!clientSize && ((compareBottom <= viewBottom) && (compareTop >= viewTop));
+            else if(direction === 'horizontal')
+                return !!clientSize && ((compareRight <= viewRight) && (compareLeft >= viewLeft));
+        }
+    };
+
+})(jQuery);