Function _getScrollNormalizer

esm/ScrollTrigger.js:2423–2643

(vars)

  }
},
    _getScrollNormalizer = function _getScrollNormalizer(vars) {
  _isObject(vars) || (vars = {});
  vars.preventDefault = vars.isNormalizer = vars.allowClicks = true;
  vars.type || (vars.type = "wheel,touch");
  vars.debounce = !!vars.debounce;
  vars.id = vars.id || "normalizer";

  var _vars2 = vars,
      normalizeScrollX = _vars2.normalizeScrollX,
      momentum = _vars2.momentum,
      allowNestedScroll = _vars2.allowNestedScroll,
      onRelease = _vars2.onRelease,
      self,
      maxY,
      target = _getTarget(vars.target) || _docEl,
      smoother = gsap.core.globals().ScrollSmoother,
      smootherInstance = smoother && smoother.get(),
      content = _fixIOSBug && (vars.content && _getTarget(vars.content) || smootherInstance && vars.content !== false && !smootherInstance.smooth() && smootherInstance.content()),
      scrollFuncY = _getScrollFunc(target, _vertical),
      scrollFuncX = _getScrollFunc(target, _horizontal),
      scale = 1,
      initialScale = (Observer.isTouch && _win.visualViewport ? _win.visualViewport.scale * _win.visualViewport.width : _win.outerWidth) / _win.innerWidth,
      wheelRefresh = 0,
      resolveMomentumDuration = _isFunction(momentum) ? function () {
    return momentum(self);
  } : function () {
    return momentum || 2.8;
  },
      lastRefreshID,
      skipTouchMove,
      inputObserver = _inputObserver(target, vars.type, true, allowNestedScroll),
      resumeTouchMove = function resumeTouchMove() {
    return skipTouchMove = false;
  },
      scrollClampX = _passThrough,
      scrollClampY = _passThrough,
      updateClamps = function updateClamps() {
    maxY = _maxScroll(target, _vertical);
    scrollClampY = _clamp(_fixIOSBug ? 1 : 0, maxY);
    normalizeScrollX && (scrollClampX = _clamp(0, _maxScroll(target, _horizontal)));
    lastRefreshID = _refreshID;
  },
      removeContentOffset = function removeContentOffset() {
    content._gsap.y = _round(parseFloat(content._gsap.y) + scrollFuncY.offset) + "px";
    content.style.transform = "matrix3d(1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, " + parseFloat(content._gsap.y) + ", 0, 1)";
    scrollFuncY.offset = scrollFuncY.cacheID = 0;
  },
      ignoreDrag = function ignoreDrag() {
    if (skipTouchMove) {
      requestAnimationFrame(resumeTouchMove);

      var offset = _round(self.deltaY / 2),
          scroll = scrollClampY(scrollFuncY.v - offset);

      if (content && scroll !== scrollFuncY.v + scrollFuncY.offset) {
        scrollFuncY.offset = scroll - scrollFuncY.v;

        var y = _round((parseFloat(content && content._gsap.y) || 0) - scrollFuncY.offset);