Function _getScrollFunc

esm/Observer.js:139–159

(element, _ref)

  return false;
},
    _getScrollFunc = function _getScrollFunc(element, _ref) {
  var s = _ref.s,
      sc = _ref.sc;
  // we store the scroller functions in an alternating sequenced Array like [element, verticalScrollFunc, horizontalScrollFunc, ...] so that we can minimize memory, maximize performance, and we also record the last position as a ".rec" property in order to revert to that after refreshing to ensure things don't shift around.
  _isViewport(element) && (element = _doc.scrollingElement || _docEl);

  var i = _scrollers.indexOf(element),
      offset = sc === _vertical.sc ? 1 : 2;

  !~i && (i = _scrollers.push(element) - 1);
  _scrollers[i + offset] || _addListener(element, "scroll", _onScroll); // clear the cache when a scroll occurs

  var prev = _scrollers[i + offset],
      func = prev || (_scrollers[i + offset] = _scrollCacheFunc(_getProxyProp(element, s), true) || (_isViewport(element) ? sc : _scrollCacheFunc(function (value) {
    return arguments.length ? element[s] = value : element[s];
  })));
  func.target = element;
  prev || (func.smooth = gsap.getProperty(element, "scrollBehavior") === "smooth"); // only set it the first time (don't reset every time a scrollFunc is requested because perhaps it happens during a refresh() when it's disabled in ScrollTrigger.

  return func;
},
    _getVelocityProp = function _getVelocityProp(value, minTimeRefresh, useDelta) {
  var v1 = value,
      v2 = value,