| /* |
| * Viewport - jQuery selectors for finding elements in viewport |
| * |
| * Copyright (c) 2008-2009 Mika Tuupola |
| * |
| * Licensed under the MIT license: |
| * http://www.opensource.org/licenses/mit-license.php |
| * |
| * Project home: |
| * http://www.appelsiini.net/projects/viewport |
| * |
| */ |
| (function($) { |
| |
| $.belowthefold = function(element, settings) { |
| var fold = $(window).height() + $(window).scrollTop(); |
| return fold <= $(element).offset().top - settings.threshold; |
| }; |
| |
| $.abovethetop = function(element, settings) { |
| var top = $(window).scrollTop(); |
| return top >= $(element).offset().top + $(element).height() - settings.threshold; |
| }; |
| |
| $.rightofscreen = function(element, settings) { |
| var fold = $(window).width() + $(window).scrollLeft(); |
| return fold <= $(element).offset().left - settings.threshold; |
| }; |
| |
| $.leftofscreen = function(element, settings) { |
| var left = $(window).scrollLeft(); |
| return left >= $(element).offset().left + $(element).width() - settings.threshold; |
| }; |
| |
| $.inviewport = function(element, settings) { |
| return !$.rightofscreen(element, settings) && !$.leftofscreen(element, settings) && !$.belowthefold(element, settings) && !$.abovethetop(element, settings); |
| }; |
| |
| $.extend($.expr[':'], { |
| "below-the-fold": function(a, i, m) { |
| return $.belowthefold(a, {threshold : 0}); |
| }, |
| "above-the-top": function(a, i, m) { |
| return $.abovethetop(a, {threshold : 0}); |
| }, |
| "left-of-screen": function(a, i, m) { |
| return $.leftofscreen(a, {threshold : 0}); |
| }, |
| "right-of-screen": function(a, i, m) { |
| return $.rightofscreen(a, {threshold : 0}); |
| }, |
| "in-viewport": function(a, i, m) { |
| return $.inviewport(a, {threshold : 0}); |
| } |
| }); |
| |
| |
| })(jQuery); |