phaser/Phaser/tweens/easing/Elastic.js

var Phaser;
(function (Phaser) {
    /// <reference path="../../_definitions.ts" />
    /**
    * Phaser - Easing - Elastic
    *
    * For use with Phaser.Tween
    */
    (function (Easing) {
        var Elastic = (function () {
            function Elastic() {
            }
            Elastic.In = function (k) {
                var s, a = 0.1, p = 0.4;
                if (k === 0)
                    return 0;
                if (k === 1)
                    return 1;
                if (!a || a < 1) {
                    a = 1;
                    s = p / 4;
                } else
                    s = p * Math.asin(1 / a) / (2 * Math.PI);
                return -(a * Math.pow(2, 10 * (k -= 1)) * Math.sin((k - s) * (2 * Math.PI) / p));
            };

            Elastic.Out = function (k) {
                var s, a = 0.1, p = 0.4;
                if (k === 0)
                    return 0;
                if (k === 1)
                    return 1;
                if (!a || a < 1) {
                    a = 1;
                    s = p / 4;
                } else
                    s = p * Math.asin(1 / a) / (2 * Math.PI);
                return (a * Math.pow(2, -10 * k) * Math.sin((k - s) * (2 * Math.PI) / p) + 1);
            };

            Elastic.InOut = function (k) {
                var s, a = 0.1, p = 0.4;
                if (k === 0)
                    return 0;
                if (k === 1)
                    return 1;
                if (!a || a < 1) {
                    a = 1;
                    s = p / 4;
                } else
                    s = p * Math.asin(1 / a) / (2 * Math.PI);
                if ((k *= 2) < 1)
                    return -0.5 * (a * Math.pow(2, 10 * (k -= 1)) * Math.sin((k - s) * (2 * Math.PI) / p));
                return a * Math.pow(2, -10 * (k -= 1)) * Math.sin((k - s) * (2 * Math.PI) / p) * 0.5 + 1;
            };
            return Elastic;
        })();
        Easing.Elastic = Elastic;
    })(Phaser.Easing || (Phaser.Easing = {}));
    var Easing = Phaser.Easing;
})(Phaser || (Phaser = {}));