Removed legacy rollup options

dist/dsap.es.js

@@ -1,11 +1,46 @@
-class o {
+var d = Object.defineProperty;
+var h = (l, e, t) => e in l ? d(l, e, { enumerable: !0, configurable: !0, writable: !0, value: t }) : l[e] = t;
+var r = (l, e, t) => (h(l, typeof e != "symbol" ? e + "" : e, t), t);
+class u {
   constructor() {
-    window.addEventListener("scroll", this.scroll.bind(this));
+    // Setup elems variable
+    r(this, "elems");
+    // Set the range of the viewport delta to 1000. The higher the number, the better "resolution" of the scroll delta
+    r(this, "maxScrollDelta", 1e3);
+    this.init();
   }
-  scroll() {
-    console.log("scrolling");
+  init() {
+    this.elems = document.querySelectorAll("[data-dsap]"), document.documentElement.style.setProperty("--dsap-max-scroll-delta", this.maxScrollDelta), window.addEventListener(
+      "scroll",
+      // Pass scroll event through a debounce function which runs it through requestAnimationFrame to improve performance
+      this.debounce(this.onScroll.bind(this)),
+      // Ensure passive event listeners are used where possible to improve scrolling performance
+      { passive: !0 }
+    );
+  }
+  onScroll() {
+    const e = window.scrollY, t = e + window.innerHeight;
+    this.elems.forEach((o) => {
+      const n = o.getBoundingClientRect().top + e, c = n + o.getBoundingClientRect().height;
+      let i = !1, s = !1, a = 0;
+      t < n ? s = !1 : e > c ? s = !0 : i = !0, i ? a = ((t - n) / (o.getBoundingClientRect().height + window.innerHeight) * this.maxScrollDelta).toFixed(0) : s && (a = this.maxScrollDelta), o.dataset.dsapIs = i ? "in" : s ? "above" : "below", i && (o.dataset.dsapSeen = !0), o.style.setProperty("--dsap-scroll-delta", a);
+    });
+  }
+  /**
+   * A debounce function that uses requestAnimationFrame
+   * @param {function} fn - Function to debounce 
+   * 
+   * Credit: https://pqina.nl/blog/applying-styles-based-on-the-user-scroll-position-with-smart-css/
+   */
+  debounce(e) {
+    let t;
+    return (...o) => {
+      t && cancelAnimationFrame(t), t = requestAnimationFrame(() => {
+        e(...o);
+      });
+    };
   }
 }
 export {
-  o as DSAP
+  u as DSAP
 };

vite.config.js

@@ -9,19 +9,6 @@ module.exports = defineConfig({
       entry: path.resolve(__dirname, 'lib/main.js'),
       name: 'dsap',
       fileName: (format) => `dsap.${format}.js`,
-    },
-    // compile scss to css
-    rollupOptions: {
-        plugins: [
-            scss({
-                includePaths: ['./styles'],
-                output: './dist/dsap.css',
-                failOnError: true,
-                outputStyle: 'compressed',
-                watch: 'styles',
-                runtime: require('sass')
-            })
-        ]
     }
   }
 });