Draggable Infinite Slider (GSAP Draggable)

<script src="https://cdn.jsdelivr.net/npm/gsap@3.15/dist/gsap.min.js"></script>
<script src="https://cdn.jsdelivr.net/npm/gsap@3.15/dist/Draggable.min.js"></script>
<script src="https://cdn.jsdelivr.net/npm/gsap@3.15/dist/InertiaPlugin.min.js"></script>

<div class="slider__section">
  <div class="slider__overlay">
    <div class="slider__overlay-inner">
      <div class="slider__overlay-count">
        <div class="slider__count-col">
          <h2 data-slide-count="step" class="slider__count-heading">01</h2>
        </div>
        <div class="slider__count-divider"></div>
        <div class="slider__count-col">
          <h2 data-slide-count="total" class="slider__count-heading">04</h2>
        </div>
      </div>
      <div class="slider__overlay-nav">
        <button aria-label="previous slide" data-slider-button="prev" class="slider__btn">
          <svg xmlns="http://www.w3.org/2000/svg" width="100%" viewbox="0 0 17 12" fill="none" class="slider__btn-arrow">
            <path d="M6.28871 12L7.53907 10.9111L3.48697 6.77778H16.5V5.22222H3.48697L7.53907 1.08889L6.28871 0L0.5 6L6.28871 12Z" fill="currentColor"></path>
          </svg>
          <div class="slider__btn-overlay">
            <div class="slider__btn-overlay-corner"></div>
            <div class="slider__btn-overlay-corner top-right"></div>
            <div class="slider__btn-overlay-corner bottom-left"></div>
            <div class="slider__btn-overlay-corner bottom-right"></div>
          </div>
        </button>
        <button aria-label="previous slide" data-slider-button="next" class="slider__btn">
          <svg xmlns="http://www.w3.org/2000/svg" width="100%" viewbox="0 0 17 12" fill="none" class="slider__btn-arrow next">
            <path d="M6.28871 12L7.53907 10.9111L3.48697 6.77778H16.5V5.22222H3.48697L7.53907 1.08889L6.28871 0L0.5 6L6.28871 12Z" fill="currentColor"></path>
          </svg>
          <div class="slider__btn-overlay">
            <div class="slider__btn-overlay-corner"></div>
            <div class="slider__btn-overlay-corner top-right"></div>
            <div class="slider__btn-overlay-corner bottom-left"></div>
            <div class="slider__btn-overlay-corner bottom-right"></div>
          </div>
        </button>
      </div>
    </div>
  </div>
  <div class="slider__main">
    <div class="slider__wrap">
      <div data-slider="list" class="slider__list">
        <div data-slider="slide" class="slider__slide">
          <div class="slider__slide-inner"><img src="https://cdn.prod.website-files.com/67696d1cd4b1d776a63f0f94/690b581ba59c96e073460cd1_Cinematic%20Motion%20Portrait.avif" class="slide__img">
            <div class="slide__caption">
              <div class="slide__caption-dot"></div>
              <p class="slide__caption-label">Image nº005</p>
            </div>
          </div>
        </div>
        <div data-slider="slide" class="slider__slide active">
          <div class="slider__slide-inner"><img src="https://cdn.prod.website-files.com/67696d1cd4b1d776a63f0f94/690b581b4e66ce6d99185126_Child%20in%20Sunset%20Meadow.avif" class="slide__img">
            <div class="slide__caption">
              <div class="slide__caption-dot"></div>
              <p class="slide__caption-label">Image nº001</p>
            </div>
          </div>
        </div>
        <div data-slider="slide" class="slider__slide">
          <div class="slider__slide-inner"><img src="https://cdn.prod.website-files.com/67696d1cd4b1d776a63f0f94/690b581b644385ab3c4845f8_Woman%20in%20Coastal%20Field.avif" class="slide__img">
            <div class="slide__caption">
              <div class="slide__caption-dot"></div>
              <p class="slide__caption-label">Image nº002</p>
            </div>
          </div>
        </div>
        <div data-slider="slide" class="slider__slide">
          <div class="slider__slide-inner"><img src="https://cdn.prod.website-files.com/67696d1cd4b1d776a63f0f94/690b581bae1e27262dcfe889_Runner%20at%20Golden%20Hour.avif" class="slide__img">
            <div class="slide__caption">
              <div class="slide__caption-dot"></div>
              <p class="slide__caption-label">Image nº003</p>
            </div>
          </div>
        </div>
        <div data-slider="slide" class="slider__slide">
          <div class="slider__slide-inner"><img src="https://cdn.prod.website-files.com/67696d1cd4b1d776a63f0f94/690b581b7c6e8ac0e1960406_Golden%20Hour%20Serenity.avif" class="slide__img">
            <div class="slide__caption">
              <div class="slide__caption-dot"></div>
              <p class="slide__caption-label">Layout nº004</p>
            </div>
          </div>
        </div>
      </div>
    </div>
  </div>
</div>

.slider__section{
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  display: flex;
  position: relative;  
  background-color: #20261b;
}

.slider__main {
  z-index: 0;
  width: 100%;
  height: 100%;
  position: absolute;
  inset: 0%;
  overflow: hidden;
}

.slider__wrap {
  justify-content: flex-start;
  align-items: center;
  width: 100%;
  height: 100%;
  display: flex;
}

.slider__list {
  flex-flow: row;
  justify-content: flex-start;
  align-items: stretch;
  display: flex;
  position: relative;
}

.slider__slide {
  aspect-ratio: 3 / 2;
  flex: none;
  width: 36vw;
  padding-left: 1.25em;
  padding-right: 1.25em;
  transition: opacity .4s;
  position: relative;
}

.slider__slide-inner {
  border-radius: .5em;
  width: 100%;
  height: 100%;
  position: relative;
  overflow: hidden;
}

.slide__img {
  object-fit: cover;
  width: 100%;
  height: 100%;
}

.slide__caption {
  z-index: 2;
  grid-column-gap: .4em;
  grid-row-gap: .4em;
  -webkit-backdrop-filter: blur(5px);
  backdrop-filter: blur(5px);
  color: #fff;
  white-space: nowrap;
  background-color: #efeeec26;
  border-radius: .25em;
  justify-content: flex-start;
  align-items: center;
  padding: .4em .75em .4em .5em;
  display: flex;
  position: absolute;
  top: 1.25em;
  left: 1.25em;
  overflow: hidden;
}

.slide__caption-dot {
  background-color: #a1ff62;
  border-radius: 10em;
  flex: none;
  width: .5em;
  height: .5em;
}

.slide__caption-label {
  margin-top: 0;
  margin-bottom: 0;
  font-size: .75em;
  line-height: 1.5;
}

.slider__overlay {
  z-index: 2;
  color: #fff;
  background-image: linear-gradient(90deg, #20261b 85%, #20261b00);
  justify-content: flex-start;
  align-items: center;
  width: 36vw;
  height: 100%;
  padding-left: 2em;
  display: flex;
  position: absolute;
  inset: 0% auto 0% 0%;
}

.slider__overlay-inner {
  flex-flow: column;
  justify-content: space-between;
  align-items: flex-start;
  height: 28.125em;
  display: flex;
}

.slider__overlay-count {
  grid-column-gap: .2em;
  grid-row-gap: .2em;
  flex-flow: row;
  justify-content: flex-start;
  align-items: center;
  font-size: 4.5em;
  font-weight: 700;
  display: flex;
}

.slider__count-col {
  height: 1em;
  overflow: hidden;
}

.slider__count-heading {
  width: 2ch;
  margin-top: 0;
  margin-bottom: 0;
  font-size: 1em;
  font-weight: 400;
  line-height: 1;
}

.slider__count-divider {
  background-color: #efeeec;
  width: 2px;
  height: .75em;
  transform: rotate(15deg);
}

.slider__overlay-nav {
  grid-column-gap: 2em;
  grid-row-gap: 2em;
  display: flex;
}

.slider__btn {
  color: #fff;
  background-color: #0000;
  border: 1px solid #fff3;
  border-radius: .4em;
  justify-content: center;
  align-items: center;
  width: 4em;
  height: 4em;
  padding: 0;
  display: flex;
  position: relative;
}

.slider__btn-arrow {
  flex: none;
  width: 1em;
  height: .75em;
}

.slider__btn-arrow.next {
  transform: rotate(180deg);
}

.slider__btn-overlay {
  z-index: 2;
  position: absolute;
  inset: -1px;
}

.slider__btn-overlay-corner {
  border-top: 1px solid #efeeec;
  border-left: 1px solid #efeeec;
  border-top-left-radius: .4em;
  width: 1em;
  height: 1em;
}

.slider__btn-overlay-corner.top-right {
  position: absolute;
  inset: 0% 0% auto auto;
  transform: rotate(90deg);
}

.slider__btn-overlay-corner.bottom-right {
  position: absolute;
  inset: auto 0% 0% auto;
  transform: rotate(180deg);
}

.slider__btn-overlay-corner.bottom-left {
  position: absolute;
  inset: auto auto 0% 0%;
  transform: rotate(-90deg);
}

/* Previous and next Button*/ 
.slider__btn,
.slider__btn-overlay { 
  transition: transform 0.475s cubic-bezier(0.625, 0.05, 0, 1), opacity 0.475s cubic-bezier(0.625, 0.05, 0, 1)
}

.slider__btn:hover .slider__btn-overlay { 
  transform: scale(1.4);
}

.slider__overlay-nav:hover:has(.slider__btn:hover) .slider__btn { 
  opacity: 0.4;
}

.slider__btn:hover { 
  transform: scale(0.85);
  opacity: 1 !important;
}

/* Styling of active slide's caption */
.slide__caption {
  transition: transform 0.525s cubic-bezier(0.625, 0.05, 0, 1), opacity 0.525s cubic-bezier(0.625, 0.05, 0, 1);
  transition-delay: 0s;
}

.slide__caption {
  opacity: 0;
  transform:translate(-25%, 0px);
}

[data-slider="slide"].active .slide__caption {
  opacity: 1;
  transform:translate(0%, 0px);
}

/* Styling of active slide */
[data-slider="slide"]{ opacity: 0.2; }
[data-slider="slide"].active { opacity: 1; } 
[data-slider="slide"].active .slide__caption{ transition-delay: 0.3s; } 

@media screen and (max-width: 991px) {

  .slider__main {
    position: relative;
  }

  .slider__slide {
    width: 75vw;
  }

  .slider__overlay {
    width: 100%;
    position: relative;
    inset: auto;
    padding-bottom: 2em;
  }

  .slider__overlay-inner {
    grid-column-gap: 2em;
    grid-row-gap: 2em;
    height: auto;
  }

}

@media screen and (max-width: 479px) {
  .slider__overlay {
    padding-left: 1.25em;
  }

  .slider__slide {
    width: 90vw;
    padding-left: .5em;
    padding-right: .5em;
  }

  .slide__caption {
    top: .5em;
    left: .5em;
  }
}

gsap.registerPlugin(Draggable, InertiaPlugin)

function initDraggableInfiniteGSAPSlider(){

  const wrapper = document.querySelector('[data-slider="list"]');
  if (!wrapper) return;

  const slides = gsap.utils.toArray('[data-slider="slide"]');
  const nextButton = document.querySelector('[data-slider-button="next"]');
  const prevButton = document.querySelector('[data-slider-button="prev"]');

  const totalElement = document.querySelector('[data-slide-count="total"]');
  const stepElement = document.querySelector('[data-slide-count="step"]');
  const stepsParent = stepElement?.parentElement;

  let activeElement;
  const totalSlides = slides.length;

  // Total
  if (totalElement) totalElement.textContent = totalSlides < 10 ? `0${totalSlides}` : totalSlides;

  // Steps (clone)
  if (stepsParent && stepElement) {
    stepsParent.innerHTML = '';
    slides.forEach((_, index) => {
      const stepClone = stepElement.cloneNode(true);
      stepClone.textContent = index + 1 < 10 ? `0${index + 1}` : (index + 1);
      stepsParent.appendChild(stepClone);
    });
  }
  const allSteps = stepsParent ? stepsParent.querySelectorAll('[data-slide-count="step"]') : [];

  // Responsive
  const mq = window.matchMedia('(min-width: 992px)');
  let useNextForActive = mq.matches;
  mq.addEventListener('change', (e) => {
    useNextForActive = e.matches;
    // Re-apply active to the correct element for this breakpoint
    if (currentEl) {
      applyActive(currentEl, currentIndex, /*animateNumbers=*/false);
    }
  });

  // Keep track of the current element & index from onChange
  let currentEl = null;
  let currentIndex = 0;

  function resolveActive(el) {
    return useNextForActive ? (el.nextElementSibling || slides[0]) : el;
  }

  function applyActive(el, index, animateNumbers = true) {
    // Swap active class
    if (activeElement) activeElement.classList.remove('active');
    const target = resolveActive(el);
    target.classList.add('active');
    activeElement = target;

    // Update numbers (animate or snap)
    if (allSteps.length) {
      if (animateNumbers) {
        gsap.to(allSteps, { y: `${-100 * index}%`, ease: "power3", duration: 0.45 });
      } else {
        gsap.set(allSteps, { y: `${-100 * index}%` });
      }
    }
  }

  const loop = horizontalLoop(slides, {
    paused: true,
    draggable: true,
    center: false,
    onChange: (element, index) => {
      // remember latest
      currentEl = element;
      currentIndex = index;
      // apply for current breakpoint
      applyActive(element, index, true);
    }
  });

  // Click -> go to index (offset only on desktop offset design)
  function mapClickIndex(i) { return useNextForActive ? (i - 1) : i; }
  slides.forEach((slide, i) => {
    slide.addEventListener("click", () => {
      if (slide.classList.contains("active")) return;
      loop.toIndex(mapClickIndex(i), { ease: "power3", duration: 0.725 });
    });
  });

  nextButton?.addEventListener("click", () => loop.next({ ease:"power3", duration: 0.725 }));
  prevButton?.addEventListener("click", () => loop.previous({ ease:"power3", duration: 0.725 }));

  if (!currentEl && slides[0]) {
    currentEl = slides[0];
    currentIndex = 0;
    applyActive(currentEl, currentIndex, false);
  }
}

function horizontalLoop(items, config) {
  let timeline;
  items = gsap.utils.toArray(items);
  config = config || {};
  gsap.context(() => { 
    let onChange = config.onChange,
      lastIndex = 0,
      tl = gsap.timeline({repeat: config.repeat, onUpdate: onChange && function() {
          let i = tl.closestIndex();
          if (lastIndex !== i) {
            lastIndex = i;
            onChange(items[i], i);
          }
        }, paused: config.paused, defaults: {ease: "none"}, onReverseComplete: () => tl.totalTime(tl.rawTime() + tl.duration() * 100)}),
      length = items.length,
      startX = items[0].offsetLeft,
      times = [],
      widths = [],
      spaceBefore = [],
      xPercents = [],
      curIndex = 0,
      indexIsDirty = false,
      center = config.center,
      pixelsPerSecond = (config.speed || 1) * 100,
      snap = config.snap === false ? v => v : gsap.utils.snap(config.snap || 1), // some browsers shift by a pixel to accommodate flex layouts, so for example if width is 20% the first element's width might be 242px, and the next 243px, alternating back and forth. So we snap to 5 percentage points to make things look more natural
      timeOffset = 0,
      container = center === true ? items[0].parentNode : gsap.utils.toArray(center)[0] || items[0].parentNode,
      totalWidth,
      getTotalWidth = () => items[length-1].offsetLeft + xPercents[length-1] / 100 * widths[length-1] - startX + spaceBefore[0] + items[length-1].offsetWidth * gsap.getProperty(items[length-1], "scaleX") + (parseFloat(config.paddingRight) || 0),
      populateWidths = () => {
        let b1 = container.getBoundingClientRect(), b2;
        items.forEach((el, i) => {
          widths[i] = parseFloat(gsap.getProperty(el, "width", "px"));
          xPercents[i] = snap(parseFloat(gsap.getProperty(el, "x", "px")) / widths[i] * 100 + gsap.getProperty(el, "xPercent"));
          b2 = el.getBoundingClientRect();
          spaceBefore[i] = b2.left - (i ? b1.right : b1.left);
          b1 = b2;
        });
        gsap.set(items, { // convert "x" to "xPercent" to make things responsive, and populate the widths/xPercents Arrays to make lookups faster.
          xPercent: i => xPercents[i]
        });
        totalWidth = getTotalWidth();
      },
      timeWrap,
      populateOffsets = () => {
        timeOffset = center ? tl.duration() * (container.offsetWidth / 2) / totalWidth : 0;
        center && times.forEach((t, i) => {
          times[i] = timeWrap(tl.labels["label" + i] + tl.duration() * widths[i] / 2 / totalWidth - timeOffset);
        });
      },
      getClosest = (values, value, wrap) => {
        let i = values.length,
          closest = 1e10,
          index = 0, d;
        while (i--) {
          d = Math.abs(values[i] - value);
          if (d > wrap / 2) {
            d = wrap - d;
          }
          if (d < closest) {
            closest = d;
            index = i;
          }
        }
        return index;
      },
      populateTimeline = () => {
        let i, item, curX, distanceToStart, distanceToLoop;
        tl.clear();
        for (i = 0; i < length; i++) {
          item = items[i];
          curX = xPercents[i] / 100 * widths[i];
          distanceToStart = item.offsetLeft + curX - startX + spaceBefore[0];
          distanceToLoop = distanceToStart + widths[i] * gsap.getProperty(item, "scaleX");
          tl.to(item, {xPercent: snap((curX - distanceToLoop) / widths[i] * 100), duration: distanceToLoop / pixelsPerSecond}, 0)
            .fromTo(item, {xPercent: snap((curX - distanceToLoop + totalWidth) / widths[i] * 100)}, {xPercent: xPercents[i], duration: (curX - distanceToLoop + totalWidth - curX) / pixelsPerSecond, immediateRender: false}, distanceToLoop / pixelsPerSecond)
            .add("label" + i, distanceToStart / pixelsPerSecond);
          times[i] = distanceToStart / pixelsPerSecond;
        }
        timeWrap = gsap.utils.wrap(0, tl.duration());
      },
      refresh = (deep) => {
        let progress = tl.progress();
        tl.progress(0, true);
        populateWidths();
        deep && populateTimeline();
        populateOffsets();
        deep && tl.draggable ? tl.time(times[curIndex], true) : tl.progress(progress, true);
      },
      onResize = () => refresh(true),
      proxy;
    gsap.set(items, {x: 0});
    populateWidths();
    populateTimeline();
    populateOffsets();
    window.addEventListener("resize", onResize);
    function toIndex(index, vars) {
      vars = vars || {};
      (Math.abs(index - curIndex) > length / 2) && (index += index > curIndex ? -length : length); // always go in the shortest direction
      let newIndex = gsap.utils.wrap(0, length, index),
        time = times[newIndex];
      if (time > tl.time() !== index > curIndex && index !== curIndex) { // if we're wrapping the timeline's playhead, make the proper adjustments
        time += tl.duration() * (index > curIndex ? 1 : -1);
      }
      if (time < 0 || time > tl.duration()) {
        vars.modifiers = {time: timeWrap};
      }
      curIndex = newIndex;
      vars.overwrite = true;
      gsap.killTweensOf(proxy);    
      return vars.duration === 0 ? tl.time(timeWrap(time)) : tl.tweenTo(time, vars);
    }
    tl.toIndex = (index, vars) => toIndex(index, vars);
    tl.closestIndex = setCurrent => {
      let index = getClosest(times, tl.time(), tl.duration());
      if (setCurrent) {
        curIndex = index;
        indexIsDirty = false;
      }
      return index;
    };
    tl.current = () => indexIsDirty ? tl.closestIndex(true) : curIndex;
    tl.next = vars => toIndex(tl.current()+1, vars);
    tl.previous = vars => toIndex(tl.current()-1, vars);
    tl.times = times;
    tl.progress(1, true).progress(0, true); // pre-render for performance
    if (config.reversed) {
      tl.vars.onReverseComplete();
      tl.reverse();
    }
    if (config.draggable && typeof(Draggable) === "function") {
      proxy = document.createElement("div")
      let wrap = gsap.utils.wrap(0, 1),
        ratio, startProgress, draggable, dragSnap, lastSnap, initChangeX, wasPlaying,
        align = () => tl.progress(wrap(startProgress + (draggable.startX - draggable.x) * ratio)),
        syncIndex = () => tl.closestIndex(true);
      typeof(InertiaPlugin) === "undefined" && console.warn("InertiaPlugin required for momentum-based scrolling and snapping. https://greensock.com/club");
      draggable = Draggable.create(proxy, {
        trigger: items[0].parentNode,
        type: "x",
        onPressInit() {
          let x = this.x;
          gsap.killTweensOf(tl);
          wasPlaying = !tl.paused();
          tl.pause();
          startProgress = tl.progress();
          refresh();
          ratio = 1 / totalWidth;
          initChangeX = (startProgress / -ratio) - x;
          gsap.set(proxy, {x: startProgress / -ratio});
        },
        onDrag: align,
        onThrowUpdate: align,
        overshootTolerance: 0,
        inertia: true,
        snap(value) {
          if (Math.abs(startProgress / -ratio - this.x) < 10) {
            return lastSnap + initChangeX
          }
          let time = -(value * ratio) * tl.duration(),
            wrappedTime = timeWrap(time),
            snapTime = times[getClosest(times, wrappedTime, tl.duration())],
            dif = snapTime - wrappedTime;
          Math.abs(dif) > tl.duration() / 2 && (dif += dif < 0 ? tl.duration() : -tl.duration());
          lastSnap = (time + dif) / tl.duration() / -ratio;
          return lastSnap;
        },
        onRelease() {
          syncIndex();
          draggable.isThrowing && (indexIsDirty = true);
        },
        onThrowComplete: () => {
          syncIndex();
          wasPlaying && tl.play();
        }
      })[0];
      tl.draggable = draggable;
    }
    tl.closestIndex(true);
    lastIndex = curIndex;
    onChange && onChange(items[curIndex], curIndex);
    timeline = tl;
    return () => window.removeEventListener("resize", onResize); 
  });
  return timeline;
}

// Initialize Draggable Infinite GSAP Slider
document.addEventListener('DOMContentLoaded', function() {
  initDraggableInfiniteGSAPSlider();
});