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Robert Penners easing functions js (compatible with scroll-utility)
/* ============================================================
* jQuery Easing v1.3 - http://gsgd.co.uk/sandbox/jquery/easing/
*
* Open source under the BSD License.
*
* Copyright © 2008 George McGinley Smith
* All rights reserved.
* https://raw.github.com/danro/jquery-easing/master/LICENSE
* ======================================================== */
const Easing = {
// t: current time, b: begInnIng value, c: change In value, d: duration
easeInQuad: function(t, b, c, d) {
return c * (t /= d) * t + b
},
easeOutQuad: function(t, b, c, d) {
return -c * (t /= d) * (t - 2) + b
},
easeInOutQuad: function(t, b, c, d) {
if ((t /= d / 2) < 1) return (c / 2) * t * t + b
return (-c / 2) * (--t * (t - 2) - 1) + b
},
easeInCubic: function(t, b, c, d) {
return c * (t /= d) * t * t + b
},
easeOutCubic: function(t, b, c, d) {
return c * ((t = t / d - 1) * t * t + 1) + b
},
easeInOutCubic: function(t, b, c, d) {
if ((t /= d / 2) < 1) return (c / 2) * t * t * t + b
return (c / 2) * ((t -= 2) * t * t + 2) + b
},
easeInQuart: function(t, b, c, d) {
return c * (t /= d) * t * t * t + b
},
easeOutQuart: function(t, b, c, d) {
return -c * ((t = t / d - 1) * t * t * t - 1) + b
},
easeInOutQuart: function(t, b, c, d) {
if ((t /= d / 2) < 1) return (c / 2) * t * t * t * t + b
return (-c / 2) * ((t -= 2) * t * t * t - 2) + b
},
easeInQuint: function(t, b, c, d) {
return c * (t /= d) * t * t * t * t + b
},
easeOutQuint: function(t, b, c, d) {
return c * ((t = t / d - 1) * t * t * t * t + 1) + b
},
easeInOutQuint: function(t, b, c, d) {
if ((t /= d / 2) < 1) return (c / 2) * t * t * t * t * t + b
return (c / 2) * ((t -= 2) * t * t * t * t + 2) + b
},
easeInSine: function(t, b, c, d) {
return -c * Math.cos((t / d) * (Math.PI / 2)) + c + b
},
easeOutSine: function(t, b, c, d) {
return c * Math.sin((t / d) * (Math.PI / 2)) + b
},
easeInOutSine: function(t, b, c, d) {
return (-c / 2) * (Math.cos((Math.PI * t) / d) - 1) + b
},
easeInExpo: function(t, b, c, d) {
return t == 0 ? b : c * Math.pow(2, 10 * (t / d - 1)) + b
},
easeOutExpo: function(t, b, c, d) {
return t == d ? b + c : c * (-Math.pow(2, (-10 * t) / d) + 1) + b
},
easeInOutExpo: function(t, b, c, d) {
if (t == 0) return b
if (t == d) return b + c
if ((t /= d / 2) < 1) return (c / 2) * Math.pow(2, 10 * (t - 1)) + b
return (c / 2) * (-Math.pow(2, -10 * --t) + 2) + b
},
easeInCirc: function(t, b, c, d) {
return -c * (Math.sqrt(1 - (t /= d) * t) - 1) + b
},
easeOutCirc: function(t, b, c, d) {
return c * Math.sqrt(1 - (t = t / d - 1) * t) + b
},
easeInOutCirc: function(t, b, c, d) {
if ((t /= d / 2) < 1) return (-c / 2) * (Math.sqrt(1 - t * t) - 1) + b
return (c / 2) * (Math.sqrt(1 - (t -= 2) * t) + 1) + b
},
easeInElastic: function(t, b, c, d) {
var s = 1.70158
var p = 0
var a = c
if (t == 0) return b
if ((t /= d) == 1) return b + c
if (!p) p = d * 0.3
if (a < Math.abs(c)) {
a = c
var s = p / 4
} else var s = (p / (2 * Math.PI)) * Math.asin(c / a)
return -(a * Math.pow(2, 10 * (t -= 1)) * Math.sin(((t * d - s) * (2 * Math.PI)) / p)) + b
},
easeOutElastic: function(t, b, c, d) {
var s = 1.70158
var p = 0
var a = c
if (t == 0) return b
if ((t /= d) == 1) return b + c
if (!p) p = d * 0.3
if (a < Math.abs(c)) {
a = c
var s = p / 4
} else var s = (p / (2 * Math.PI)) * Math.asin(c / a)
return a * Math.pow(2, -10 * t) * Math.sin(((t * d - s) * (2 * Math.PI)) / p) + c + b
},
easeInOutElastic: function(t, b, c, d) {
var s = 1.70158
var p = 0
var a = c
if (t == 0) return b
if ((t /= d / 2) == 2) return b + c
if (!p) p = d * (0.3 * 1.5)
if (a < Math.abs(c)) {
a = c
var s = p / 4
} else var s = (p / (2 * Math.PI)) * Math.asin(c / a)
if (t < 1)
return (
-0.5 * (a * Math.pow(2, 10 * (t -= 1)) * Math.sin(((t * d - s) * (2 * Math.PI)) / p)) + b
)
return (
a * Math.pow(2, -10 * (t -= 1)) * Math.sin(((t * d - s) * (2 * Math.PI)) / p) * 0.5 + c + b
)
},
easeInBack: function(t, b, c, d, s) {
if (s == undefined) s = 1.70158
return c * (t /= d) * t * ((s + 1) * t - s) + b
},
easeOutBack: function(t, b, c, d, s) {
if (s == undefined) s = 1.70158
return c * ((t = t / d - 1) * t * ((s + 1) * t + s) + 1) + b
},
easeInOutBack: function(t, b, c, d, s) {
if (s == undefined) s = 1.70158
if ((t /= d / 2) < 1) return (c / 2) * (t * t * (((s *= 1.525) + 1) * t - s)) + b
return (c / 2) * ((t -= 2) * t * (((s *= 1.525) + 1) * t + s) + 2) + b
},
easeInBounce: function(t, b, c, d) {
return c - Easing.easeOutBounce(d - t, 0, c, d) + b
},
easeOutBounce: function(t, b, c, d) {
if ((t /= d) < 1 / 2.75) {
return c * (7.5625 * t * t) + b
} else if (t < 2 / 2.75) {
return c * (7.5625 * (t -= 1.5 / 2.75) * t + 0.75) + b
} else if (t < 2.5 / 2.75) {
return c * (7.5625 * (t -= 2.25 / 2.75) * t + 0.9375) + b
} else {
return c * (7.5625 * (t -= 2.625 / 2.75) * t + 0.984375) + b
}
},
easeInOutBounce: function(t, b, c, d) {
if (t < d / 2) return Easing.easeInBounce(t * 2, 0, c, d) * 0.5 + b
return Easing.easeOutBounce(t * 2 - d, 0, c, d) * 0.5 + c * 0.5 + b
},
}
window.Easing = Easing
/*
*
* TERMS OF USE - EASING EQUATIONS
*
* Open source under the BSD License.
*
* Copyright © 2001 Robert Penner
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* Redistributions of source code must retain the above copyright notice, this list of
* conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright notice, this list
* of conditions and the following disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* Neither the name of the author nor the names of contributors may be used to endorse
* or promote products derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
* GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
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