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@@ -0,0 +1,58 @@
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+Math.easeInOutQuad = function(t, b, c, d) {
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+ t /= d / 2
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+ if (t < 1) {
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+ return c / 2 * t * t + b
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+ }
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+ t--
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+ return -c / 2 * (t * (t - 2) - 1) + b
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+}
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+
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+// requestAnimationFrame for Smart Animating http://goo.gl/sx5sts
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+var requestAnimFrame = (function() {
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+ return window.requestAnimationFrame || window.webkitRequestAnimationFrame || window.mozRequestAnimationFrame || function(callback) { window.setTimeout(callback, 1000 / 60) }
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+})()
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+
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+/**
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+ * Because it's so fucking difficult to detect the scrolling element, just move them all
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+ * @param {number} amount
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+ */
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+function move(amount) {
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+ document.documentElement.scrollTop = amount
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+ document.body.parentNode.scrollTop = amount
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+ document.body.scrollTop = amount
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+}
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+
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+function position() {
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+ return document.documentElement.scrollTop || document.body.parentNode.scrollTop || document.body.scrollTop
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+}
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+
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+/**
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+ * @param {number} to
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+ * @param {number} duration
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+ * @param {Function} callback
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+ */
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+export function scrollTo(to, duration, callback) {
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+ const start = position()
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+ const change = to - start
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+ const increment = 20
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+ let currentTime = 0
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+ duration = (typeof (duration) === 'undefined') ? 500 : duration
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+ var animateScroll = function() {
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+ // increment the time
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+ currentTime += increment
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+ // find the value with the quadratic in-out easing function
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+ var val = Math.easeInOutQuad(currentTime, start, change, duration)
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+ // move the document.body
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+ move(val)
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+ // do the animation unless its over
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+ if (currentTime < duration) {
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+ requestAnimFrame(animateScroll)
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+ } else {
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+ if (callback && typeof (callback) === 'function') {
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+ // the animation is done so lets callback
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+ callback()
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+ }
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+ }
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+ }
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+ animateScroll()
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+}
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