https://realfastfunds.com/wp-content/plugins/breakdance/plugin/ani…/scrolling/js/blur-plugin.js?bd_ver=2.8.1

1// Custom plugin to add 'blur' property
2// Usage: gsap.to(target, {blur:10}) and it'll feed that value to this plugin
3// which will do all the necessary calculations to add/update a blur() value
4// in the CSS "filter" property (in browsers that support it).
5
6// Source, found in the gsap forums:
7// https://codepen.io/GreenSock/pen/NWKjEBG
8
9(function() {
10  const blurProperty = gsap.utils.checkPrefix("filter"),
11    blurExp = /blur\((.+)?px\)/,
12    getBlurMatch = target =>
13      (gsap.getProperty(target, blurProperty) || "").match(blurExp) || [];
14
15  gsap.registerPlugin({
16    name: "blur",
17    get(target) {
18      return +getBlurMatch(target)[1] || 0;
19    },
20    init(target, endValue) {
21      let data = this,
22        filter = gsap.getProperty(target, blurProperty),
23        endBlur = "blur(" + endValue + "px)",
24        match = getBlurMatch(target)[0],
25        index;
26      if (filter === "none") {
27        filter = "";
28      }
29      if (match) {
30        index = filter.indexOf(match);
31        endValue =
32          filter.substr(0, index) +
33          endBlur +
34          filter.substr(index + match.length);
35      } else {
36        endValue = filter + endBlur;
37        filter += filter ? " blur(0px)" : "blur(0px)";
38      }
39      data.target = target;
40      data.interp = gsap.utils.interpolate(filter, endValue);
41    },
42    render(progress, data) {
43      data.target.style[blurProperty] = data.interp(progress);
44    }
45  });
46})();