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December 12, 2011 18:06
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This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters. Learn more about bidirectional Unicode charactersOriginal file line number Diff line number Diff line change @@ -0,0 +1,82 @@ // jQuery.addEasing(string) // // Interprets and adds easing functions to jQuery.easing // according to the CSS spec for transition timing functions. // // e.g. // jQuery.addEasing('cubic-bezier(0.4, 0.2, 0.66, 1)'); (function(jQuery, undefined){ // Timing function definitions from the CSS specification var easing = { 'linear': [0, 0, 1, 1], 'ease': [0.25, 0.1, 0.25, 1], 'ease-in': [0.42, 0, 1, 1], 'ease-out': [0, 0, 0.58, 1], 'ease-in-out': [0.42, 0, 0.58, 1] }; // Cubic bezier function purloined from // blogs.msdn.com/b/eternalcoding/archive/2011/12/06/css3-transitions.aspx function makeBezier(x1, y1, x2, y2) { return function (t) { // Extract X (which is equal to time here) var f0 = 1 - 3 * x2 + 3 * x1, f1 = 3 * x2 - 6 * x1, f2 = 3 * x1, refinedT = t, i, refinedT2, refinedT3, x, slope; for (i = 0; i < 5; i++) { refinedT2 = refinedT * refinedT; refinedT3 = refinedT2 * refinedT; x = f0 * refinedT3 + f1 * refinedT2 + f2 * refinedT; slope = 1.0 / (3.0 * f0 * refinedT2 + 2.0 * f1 * refinedT + f2); refinedT -= (x - t) * slope; refinedT = Math.min(1, Math.max(0, refinedT)); } return 3 * Math.pow(1 - refinedT, 2) * refinedT * y1 + 3 * (1 - refinedT) * Math.pow(refinedT, 2) * y2 + Math.pow(refinedT, 3); }; } function addEasing(str) { var fn = jQuery.easing[str], name, coords, l; // Return the cached function if it exists. if (fn) { return fn; } // Get the standard easing function if it's defined. if (easing[str]) { name = str; coords = easing[str]; str = 'cubic-bezier(' + coords.join(', ') + ')'; } // Else assume this is a cubic-bezier. It must be. else { coords = str.match(/\d*\.?\d+/g); l = coords.length; // Should be 4 while (l--) { coords[l] = parseFloat(coords[l]); } } fn = makeBezier.apply(this, coords); jQuery.easing[str] = fn; if (name) { jQuery.easing[name] = fn }; return fn; } jQuery.addEasing = addEasing; })(jQuery);