Сбои / прыжки / вылеты на триггерах SmoothScroll + ScrollMagic + GSAP

Попробуйте, это обязательно поможет.

(function() {
var defaultOptions = { frameRate: 150, animationTime: 400, stepSize: 100, pulseAlgorithm: true, pulseScale: 4, pulseNormalize: 1, accelerationDelta: 50, accelerationMax: 3, keyboardSupport: true, arrowScroll: 50, fixedBackground: true, excluded: '' };
var options = defaultOptions;
var isExcluded = false;
var isFrame = false;
var direction = { x: 0, y: 0 };
var initDone = false;
var root = document.documentElement;
var activeElement;
var observer;
var refreshSize;
var deltaBuffer = [];
var isMac = /^Mac/.test(navigator.platform);
var key = { left: 37, up: 38, right: 39, down: 40, spacebar: 32, pageup: 33, pagedown: 34, end: 35, home: 36 };
var arrowKeys = { 37: 1, 38: 1, 39: 1, 40: 1 };

function initTest() { if (options.keyboardSupport) { addEvent('keydown', keydown); } }

function init() { if (initDone || !document.body) return;
    initDone = true; var body = document.body; var html = document.documentElement; var windowHeight = window.innerHeight; var scrollHeight = body.scrollHeight;
    root = (document.compatMode.indexOf('CSS') >= 0) ? html : body;
    activeElement = body;
    initTest(); if (top != self) { isFrame = true; } else if (isOldSafari && scrollHeight > windowHeight && (body.offsetHeight <= windowHeight || html.offsetHeight <= windowHeight)) { var fullPageElem = document.createElement('div');
        fullPageElem.style.cssText = 'position:absolute; z-index:-10000; ' + 'top:0; left:0; right:0; height:' + root.scrollHeight + 'px';
        document.body.appendChild(fullPageElem); var pendingRefresh;
        refreshSize = function() { if (pendingRefresh) return;
            pendingRefresh = setTimeout(function() { if (isExcluded) return;
                fullPageElem.style.height = '0';
                fullPageElem.style.height = root.scrollHeight + 'px';
                pendingRefresh = null; }, 500); };
        setTimeout(refreshSize, 10);
        addEvent('resize', refreshSize); var config = { attributes: true, childList: true, characterData: false };
        observer = new MutationObserver(refreshSize);
        observer.observe(body, config); if (root.offsetHeight <= windowHeight) { var clearfix = document.createElement('div');
            clearfix.style.clear = 'both';
            body.appendChild(clearfix); } } if (!options.fixedBackground && !isExcluded) { body.style.backgroundAttachment = 'scroll';
        html.style.backgroundAttachment = 'scroll'; } }

function cleanup() { observer && observer.disconnect();
    removeEvent(wheelEvent, wheel);
    removeEvent('mousedown', mousedown);
    removeEvent('keydown', keydown);
    removeEvent('resize', refreshSize);
    removeEvent('load', init); }
var que = [];
var pending = false;
var lastScroll = Date.now();

function scrollArray(elem, left, top) { directionCheck(left, top); if (options.accelerationMax != 1) { var now = Date.now(); var elapsed = now - lastScroll; if (elapsed < options.accelerationDelta) { var factor = (1 + (50 / elapsed)) / 2; if (factor > 1) { factor = Math.min(factor, options.accelerationMax);
                left *= factor;
                top *= factor; } } lastScroll = Date.now(); } que.push({ x: left, y: top, lastX: (left < 0) ? 0.99 : -0.99, lastY: (top < 0) ? 0.99 : -0.99, start: Date.now() }); if (pending) { return; } var scrollWindow = (elem === document.body); var step = function(time) { var now = Date.now(); var scrollX = 0; var scrollY = 0; for (var i = 0; i < que.length; i++) { var item = que[i]; var elapsed = now - item.start; var finished = (elapsed >= options.animationTime); var position = (finished) ? 1 : elapsed / options.animationTime; if (options.pulseAlgorithm) { position = pulse(position); } var x = (item.x * position - item.lastX) >> 0; var y = (item.y * position - item.lastY) >> 0;
            scrollX += x;
            scrollY += y;
            item.lastX += x;
            item.lastY += y; if (finished) { que.splice(i, 1);
                i--; } } if (scrollWindow) { window.scrollBy(scrollX, scrollY); } else { if (scrollX) elem.scrollLeft += scrollX; if (scrollY) elem.scrollTop += scrollY; } if (!left && !top) { que = []; } if (que.length) { requestFrame(step, elem, (1000 / options.frameRate + 1)); } else { pending = false; } };
    requestFrame(step, elem, 0);
    pending = true; }

function wheel(event) { if (!initDone) { init(); } var target = event.target; if (event.defaultPrevented || event.ctrlKey) { return true; } if (isNodeName(activeElement, 'embed') || (isNodeName(target, 'embed') && /\.pdf/i.test(target.src)) || isNodeName(activeElement, 'object') || target.shadowRoot) { return true; } var deltaX = -event.wheelDeltaX || event.deltaX || 0; var deltaY = -event.wheelDeltaY || event.deltaY || 0; if (isMac) { if (event.wheelDeltaX && isDivisible(event.wheelDeltaX, 120)) { deltaX = -120 * (event.wheelDeltaX / Math.abs(event.wheelDeltaX)); } if (event.wheelDeltaY && isDivisible(event.wheelDeltaY, 120)) { deltaY = -120 * (event.wheelDeltaY / Math.abs(event.wheelDeltaY)); } } if (!deltaX && !deltaY) { deltaY = -event.wheelDelta || 0; } if (event.deltaMode === 1) { deltaX *= 40;
        deltaY *= 40; } var overflowing = overflowingAncestor(target); if (!overflowing) { if (isFrame && isChrome) { Object.defineProperty(event, "target", { value: window.frameElement }); return parent.wheel(event); } return true; } if (isTouchpad(deltaY)) { return true; } if (Math.abs(deltaX) > 1.2) { deltaX *= options.stepSize / 120; } if (Math.abs(deltaY) > 1.2) { deltaY *= options.stepSize / 120; } scrollArray(overflowing, deltaX, deltaY);
    event.preventDefault();
    scheduleClearCache(); }

function keydown(event) { var target = event.target; var modifier = event.ctrlKey || event.altKey || event.metaKey || (event.shiftKey && event.keyCode !== key.spacebar); if (!document.body.contains(activeElement)) { activeElement = document.activeElement; } var inputNodeNames = /^(textarea|select|embed|object)$/i; var buttonTypes = /^(button|submit|radio|checkbox|file|color|image)$/i; if (event.defaultPrevented || inputNodeNames.test(target.nodeName) || isNodeName(target, 'input') && !buttonTypes.test(target.type) || isNodeName(activeElement, 'video') || isInsideYoutubeVideo(event) || target.isContentEditable || modifier) { return true; } if ((isNodeName(target, 'button') || isNodeName(target, 'input') && buttonTypes.test(target.type)) && event.keyCode === key.spacebar) { return true; } if (isNodeName(target, 'input') && target.type == 'radio' && arrowKeys[event.keyCode]) { return true; } var shift, x = 0,
        y = 0; var overflowing = overflowingAncestor(activeElement); if (!overflowing) { return (isFrame && isChrome) ? parent.keydown(event) : true; } var clientHeight = overflowing.clientHeight; if (overflowing == document.body) { clientHeight = window.innerHeight; } switch (event.keyCode) {
        case key.up:
            y = -options.arrowScroll; break;
        case key.down:
            y = options.arrowScroll; break;
        case key.spacebar:
            shift = event.shiftKey ? 1 : -1;
            y = -shift * clientHeight * 0.9; break;
        case key.pageup:
            y = -clientHeight * 0.9; break;
        case key.pagedown:
            y = clientHeight * 0.9; break;
        case key.home:
            y = -overflowing.scrollTop; break;
        case key.end:
            var scroll = overflowing.scrollHeight - overflowing.scrollTop; var scrollRemaining = scroll - clientHeight;
            y = (scrollRemaining > 0) ? scrollRemaining + 10 : 0; break;
        case key.left:
            x = -options.arrowScroll; break;
        case key.right:
            x = options.arrowScroll; break;
        default:
            return true; } scrollArray(overflowing, x, y);
    event.preventDefault();
    scheduleClearCache(); }

function mousedown(event) { activeElement = event.target; }
var uniqueID = (function() { var i = 0; return function(el) { return el.uniqueID || (el.uniqueID = i++); }; })();
var cache = {};
var clearCacheTimer;

function scheduleClearCache() { clearTimeout(clearCacheTimer);
    clearCacheTimer = setInterval(function() { cache = {}; }, 1 * 1000); }

function setCache(elems, overflowing) { for (var i = elems.length; i--;) cache[uniqueID(elems[i])] = overflowing; return overflowing; }

function overflowingAncestor(el) { var elems = []; var body = document.body; var rootScrollHeight = root.scrollHeight;
    do { var cached = cache[uniqueID(el)]; if (cached) { return setCache(elems, cached); } elems.push(el); if (rootScrollHeight === el.scrollHeight) { var topOverflowsNotHidden = overflowNotHidden(root) && overflowNotHidden(body); var isOverflowCSS = topOverflowsNotHidden || overflowAutoOrScroll(root); if (isFrame && isContentOverflowing(root) || !isFrame && isOverflowCSS) { return setCache(elems, getScrollRoot()); } } else if (isContentOverflowing(el) && overflowAutoOrScroll(el)) { return setCache(elems, el); } } while (el = el.parentElement); }

function isContentOverflowing(el) { return (el.clientHeight + 10 < el.scrollHeight); }

function overflowNotHidden(el) { var overflow = getComputedStyle(el, '').getPropertyValue('overflow-y'); return (overflow !== 'hidden'); }

function overflowAutoOrScroll(el) { var overflow = getComputedStyle(el, '').getPropertyValue('overflow-y'); return (overflow === 'scroll' || overflow === 'auto'); }

function addEvent(type, fn) { window.addEventListener(type, fn, false); }

function removeEvent(type, fn) { window.removeEventListener(type, fn, false); }

function isNodeName(el, tag) { return (el.nodeName || '').toLowerCase() === tag.toLowerCase(); }

function directionCheck(x, y) { x = (x > 0) ? 1 : -1;
    y = (y > 0) ? 1 : -1; if (direction.x !== x || direction.y !== y) { direction.x = x;
        direction.y = y;
        que = [];
        lastScroll = 0; } }
var deltaBufferTimer;
if (window.localStorage && localStorage.SS_deltaBuffer) { try { deltaBuffer = localStorage.SS_deltaBuffer.split(','); } catch (e) {} }

function isTouchpad(deltaY) { if (!deltaY) return; if (!deltaBuffer.length) { deltaBuffer = [deltaY, deltaY, deltaY]; } deltaY = Math.abs(deltaY);
    deltaBuffer.push(deltaY);
    deltaBuffer.shift();
    clearTimeout(deltaBufferTimer);
    deltaBufferTimer = setTimeout(function() { try { localStorage.SS_deltaBuffer = deltaBuffer.join(','); } catch (e) {} }, 1000); return !allDeltasDivisableBy(120) && !allDeltasDivisableBy(100); }

function isDivisible(n, divisor) { return (Math.floor(n / divisor) == n / divisor); }

function allDeltasDivisableBy(divisor) { return (isDivisible(deltaBuffer[0], divisor) && isDivisible(deltaBuffer[1], divisor) && isDivisible(deltaBuffer[2], divisor)); }

function isInsideYoutubeVideo(event) { var elem = event.target; var isControl = false; if (document.URL.indexOf('www.youtube.com/watch') != -1) { do { isControl = (elem.classList && elem.classList.contains('html5-video-controls')); if (isControl) break; } while (elem = elem.parentNode); } return isControl; }
var requestFrame = (function() { return (window.requestAnimationFrame || window.webkitRequestAnimationFrame || window.mozRequestAnimationFrame || function(callback, element, delay) { window.setTimeout(callback, delay || (1000 / 60)); }); })();
var MutationObserver = (window.MutationObserver || window.WebKitMutationObserver || window.MozMutationObserver);
var getScrollRoot = (function() { var SCROLL_ROOT; return function() { if (!SCROLL_ROOT) { var dummy = document.createElement('div');
            dummy.style.cssText = 'height:10000px;width:1px;';
            document.body.appendChild(dummy); var bodyScrollTop = document.body.scrollTop; var docElScrollTop = document.documentElement.scrollTop;
            window.scrollBy(0, 3); if (document.body.scrollTop != bodyScrollTop)(SCROLL_ROOT = document.body);
            else(SCROLL_ROOT = document.documentElement);
            window.scrollBy(0, -3);
            document.body.removeChild(dummy); } return SCROLL_ROOT; }; })();

function pulse_(x) { var val, start, expx;
    x = x * options.pulseScale; if (x < 1) { val = x - (1 - Math.exp(-x)); } else { start = Math.exp(-1);
        x -= 1;
        expx = 1 - Math.exp(-x);
        val = start + (expx * (1 - start)); } return val * options.pulseNormalize; }

function pulse(x) { if (x >= 1) return 1; if (x <= 0) return 0; if (options.pulseNormalize == 1) { options.pulseNormalize /= pulse_(1); } return pulse_(x); }
var userAgent = window.navigator.userAgent;
var isEdge = /Edge/.test(userAgent);
var isChrome = /chrome/i.test(userAgent) && !isEdge;
var isSafari = /safari/i.test(userAgent) && !isEdge;
var isMobile = /mobile/i.test(userAgent);
var isIEWin7 = /Windows NT 6.1/i.test(userAgent) && /rv:11/i.test(userAgent);
var isOldSafari = isSafari && (/Version\/8/i.test(userAgent) || /Version\/9/i.test(userAgent));
var isEnabledForBrowser = (isChrome || isSafari || isIEWin7) && !isMobile;
var wheelEvent;
if ('onwheel' in document.createElement('div')) wheelEvent = 'wheel';
else if ('onmousewheel' in document.createElement('div')) wheelEvent = 'mousewheel';
if (wheelEvent && isEnabledForBrowser) { addEvent(wheelEvent, wheel);
    addEvent('mousedown', mousedown);
    addEvent('load', init); }

function SmoothScroll(optionsToSet) { for (var key in optionsToSet)
        if (defaultOptions.hasOwnProperty(key)) options[key] = optionsToSet[key]; } SmoothScroll.destroy = cleanup;
if (window.SmoothScrollOptions) SmoothScroll(window.SmoothScrollOptions);
if (typeof define === 'function' && define.amd) define(function() { return SmoothScroll; });
else if ('object' == typeof exports) module.exports = SmoothScroll;
else
    window.SmoothScroll = SmoothScroll;

})();