Zoom Lens

<figure class="kodza-zoom" data-zoom="2.5">
  <img src="https://kodza.dev/media/kz-steps-1400.webp" data-zoom-src="https://kodza.dev/media/kz-steps-2400.webp" alt="Concrete steps climbing towards the light" width="1400" height="933" />
</figure>

<figure class="kodza-zoom kodza-zoom--inside" data-zoom="2.2">
  <img src="https://kodza.dev/media/kz-float-1400.webp" data-zoom-src="https://kodza.dev/media/kz-float-2400.webp" alt="Concrete slabs floating one above the other" width="1400" height="933" />
</figure>

/* Kodza License: free to use, client work included. Not to resell or redistribute, ported or not: https://kodza.dev/docs/#print-license */
/* Kodza — Zoom Lens
   A closer look under the pointer: a round lens follows it with a little lag and shows the
   detail, taken from a sharper file if you give one (data-zoom-src). --inside zooms the
   picture itself towards the pointer, inside its frame. On a touch screen the lens shows
   while the finger is down, above the finger. data-zoom sets the strength (2.5 by default).
   Everything is tuned with the --kz-zoom-* variables. */
.kodza-zoom {
  --kz-zoom-lens: 180px;
  --kz-zoom-ring: #ffffff;
  --kz-zoom-radius: 14px;
  --kz-zoom-ease: cubic-bezier(0.22, 1, 0.36, 1);

  position: relative;
  align-self: start;
  margin: 0;
  overflow: hidden;
  border-radius: var(--kz-zoom-radius);
  cursor: zoom-in;
  touch-action: pan-y;
}

.kodza-zoom img {
  display: block;
  width: 100%;
  height: auto;
  user-select: none;
  -webkit-user-drag: none;
}

/* The lens: placed by the script, it grows from the pointer when it appears */
.kodza-zoom__lens {
  position: absolute;
  top: 0;
  left: 0;
  width: var(--kz-zoom-lens);
  height: var(--kz-zoom-lens);
  border-radius: 50%;
  background-repeat: no-repeat;
  box-shadow: 0 0 0 3px var(--kz-zoom-ring), 0 18px 40px -12px rgba(0, 0, 0, 0.5);
  pointer-events: none;
  opacity: 0;
  transform: translate(var(--kz-zoom-x, 0px), var(--kz-zoom-y, 0px)) scale(0.4);
  transition: opacity 0.25s ease, transform 0.45s var(--kz-zoom-ease);
}

.kodza-zoom.is-zooming .kodza-zoom__lens {
  opacity: 1;
  transform: translate(var(--kz-zoom-x, 0px), var(--kz-zoom-y, 0px));
  transition: opacity 0.2s ease, transform 0.5s var(--kz-zoom-ease);
}

.kodza-zoom.is-moving .kodza-zoom__lens {
  transition: opacity 0.2s ease;
}

.kodza-zoom:has(.kodza-zoom__lens) {
  cursor: none;
}

/* Inside: the picture zooms towards the pointer */
.kodza-zoom--inside img {
  transform-origin: var(--kz-zoom-ox, 50%) var(--kz-zoom-oy, 50%);
  transition: transform 0.7s var(--kz-zoom-ease);
}

.kodza-zoom--inside.is-zooming img {
  transform: scale(var(--kz-zoom-scale, 2));
}

.kodza-zoom--inside:has(img) {
  cursor: zoom-in;
}

@media (prefers-reduced-motion: reduce) {
  .kodza-zoom__lens,
  .kodza-zoom--inside img {
    transition-duration: 0.01ms !important;
  }
}

/* kodza-guard 668d57fc2286 — generated by Kodza, do not edit.
   Theme guard: keeps a site's own CSS (WordPress themes, Bootstrap, CSS resets…) off this
   component. :not(#_) is always true and weighs as much as an id, so these lines win over
   theme rules made of classes and tags. Customise the component through its --kz-* variables. */

/* What the browser gives, where the component sets it only in some states: at the lowest weight, so its own rules below put it back */

:where(.kodza-zoom img:where(:not([class*="kodza-"]))):not(#_) {
  transition: revert;
}

/* What the browser gives, on everything the component leaves to it */

.kodza-zoom:not(#_) {
  border: revert;
  padding: revert;
  outline: revert;
  text-decoration: revert;
  transition: revert;
  list-style: revert;
  box-sizing: revert;
  background-color: revert;
  background-image: revert;
  box-shadow: revert;
  outline-offset: revert;
  appearance: revert;
  max-height: revert;
  color: revert;
  font-family: revert;
  font-size: revert;
  font-weight: revert;
  font-style: revert;
  line-height: revert;
  letter-spacing: revert;
  text-transform: revert;
  text-underline-offset: revert;
  text-align: revert;
  text-indent: revert;
  text-shadow: revert;
  vertical-align: revert;
}

.kodza-zoom__lens:not(#_) {
  box-sizing: revert;
}

.kodza-zoom img:where(:not([class*="kodza-"])):not(#_) {
  border: revert;
  margin: revert;
  padding: revert;
  border-radius: revert;
  outline: revert;
  text-decoration: revert;
  list-style: revert;
  box-sizing: revert;
  float: revert;
  position: revert;
  background-color: revert;
  background-image: revert;
  box-shadow: revert;
  outline-offset: revert;
  appearance: revert;
  max-width: revert;
  max-height: revert;
  color: revert;
  font-family: revert;
  font-size: revert;
  font-weight: revert;
  font-style: revert;
  line-height: revert;
  letter-spacing: revert;
  text-transform: revert;
  text-underline-offset: revert;
  text-align: revert;
  text-indent: revert;
  text-shadow: revert;
  vertical-align: revert;
}

.kodza-zoom:not(#_):where(:not([hidden])) {
  display: revert;
}

.kodza-zoom:not(#_):where([hidden]) {
  display: none;
}

/* The component's own rules, one step stronger: real buttons and fields, what it sets on tags themes style (links, lists, headings, images…), and the root width (a theme may narrow it, never widen it) */

.kodza-zoom:not(#_) {
  position: relative;
  border-radius: var(--kz-zoom-radius);
}

.kodza-zoom img:not(#_) {
  display: block;
}

.kodza-zoom--inside img:not(#_) {
  transition: transform 0.7s var(--kz-zoom-ease);
}

@media (prefers-reduced-motion: reduce) {
  .kodza-zoom--inside img:not(#_) {
    transition-duration: 0.01ms !important;
  }
}

// Kodza License: free to use, client work included. Not to resell or redistribute, ported or not: https://kodza.dev/docs/#print-license
// Kodza — Zoom Lens
// Follows the pointer with a little lag (or the finger while it is down, above it) and
// shows the detail at data-zoom, from data-zoom-src when given (loaded on first use).
// --inside moves the picture's zoom origin instead. Measured in the frame's own pixels.
(() => {
  const SELECTOR = '.kodza-zoom';
  const reduceMotion = window.matchMedia('(prefers-reduced-motion: reduce)').matches;

  // One instance. Everything it starts is tied to `signal`, so kodza:destroy stops it all
  function mount(root, signal) {
    const img = root.querySelector('img');
    if (!img) return;
    const zoom = parseFloat(root.dataset.zoom) || 2.5;
    const inside = root.classList.contains('kodza-zoom--inside');
    let lens = null;
    let x = 0;
    let y = 0;
    let tx = 0;
    let ty = 0;
    let frame = 0;
    let lift = 0;

    const sharp = () => {
      const src = img.dataset.zoomSrc;
      if (!src || img.dataset.zoomLoaded) return;
      img.dataset.zoomLoaded = 'true';
      if (inside) {
        const hi = new Image();
        hi.onload = () => (img.src = src);
        hi.src = src;
      } else lens.style.backgroundImage = `url("${src}")`;
    };

    if (inside) root.style.setProperty('--kz-zoom-scale', zoom);
    else {
      lens = Object.assign(document.createElement('span'), { className: 'kodza-zoom__lens' });
      lens.setAttribute('aria-hidden', 'true');
      lens.style.backgroundImage = `url("${img.currentSrc || img.src}")`;
      root.append(lens);
    }

    const paint = () => {
      // The picture, not the frame around it, sets the scale of the detail
      const w = img.clientWidth;
      const h = img.clientHeight;
      if (inside) {
        root.style.setProperty('--kz-zoom-ox', `${(x / w) * 100}%`);
        root.style.setProperty('--kz-zoom-oy', `${(y / h) * 100}%`);
        return;
      }
      const size = lens.offsetWidth;
      // The lens shows what is under its centre, magnified
      lens.style.backgroundSize = `${w * zoom}px ${h * zoom}px`;
      lens.style.backgroundPosition = `${-(x * zoom - size / 2)}px ${-(y * zoom - size / 2)}px`;
      root.style.setProperty('--kz-zoom-x', `${x - size / 2}px`);
      root.style.setProperty('--kz-zoom-y', `${y - size / 2 - lift}px`);
    };
    const glide = () => {
      if (signal.aborted) return;
      const k = reduceMotion ? 1 : 0.22;
      x += (tx - x) * k;
      y += (ty - y) * k;
      paint();
      frame = Math.abs(tx - x) + Math.abs(ty - y) > 0.3 ? requestAnimationFrame(glide) : 0;
    };
    const aim = (event, first) => {
      const box = root.getBoundingClientRect();
      const k = box.width / root.offsetWidth || 1;
      tx = Math.min(img.clientWidth, Math.max(0, (event.clientX - box.left) / k));
      ty = Math.min(img.clientHeight, Math.max(0, (event.clientY - box.top) / k));
      if (first) {
        x = tx;
        y = ty;
        paint();
      }
      if (!frame) frame = requestAnimationFrame(glide);
    };

    root.addEventListener('pointerenter', (event) => {
      if (event.pointerType !== 'mouse') return;
      lift = 0;
      sharp();
      aim(event, true);
      root.classList.add('is-zooming');
    }, { signal });
    root.addEventListener('pointerdown', (event) => {
      if (event.pointerType === 'mouse') return;
      // A finger would hide the lens: it shows a little above it
      lift = inside ? 0 : 90;
      sharp();
      aim(event, true);
      root.classList.add('is-zooming');
    }, { signal });
    root.addEventListener('pointermove', (event) => {
      if (!root.classList.contains('is-zooming')) return;
      root.classList.add('is-moving');
      aim(event);
    }, { signal });
    const leave = () => root.classList.remove('is-zooming', 'is-moving');
    root.addEventListener('pointerleave', leave, { signal });
    root.addEventListener('pointerup', (event) => event.pointerType !== 'mouse' && leave(), { signal });
    root.addEventListener('pointercancel', leave, { signal });
  }

  // Kodza lifecycle, the same in every component: `kodza:init` starts the instances inside
  // event.detail.root (the whole page by default), `kodza:destroy` stops them and puts their
  // markup back. For themes and apps that swap content without a page load.
  const instances = new WeakMap();
  const find = (scope = document) => [scope, ...scope.querySelectorAll(SELECTOR)].filter((el) => el.matches?.(SELECTOR));
  const init = (scope) => find(scope).forEach((root) => {
    if (root.classList.contains('is-ready')) return; // already running, maybe from another copy of this script
    const controller = new AbortController();
    instances.set(root, { controller, html: root.innerHTML, attrs: [...root.attributes].map((a) => [a.name, a.value]) });
    mount(root, controller.signal);
    root.classList.add('is-ready');
  });
  const destroy = (scope) => find(scope).forEach((root) => {
    const instance = instances.get(root);
    if (!instance) return;
    instances.delete(root);
    instance.controller.abort();
    [...root.attributes].forEach((a) => root.removeAttribute(a.name));
    instance.attrs.forEach(([name, value]) => root.setAttribute(name, value));
    root.innerHTML = instance.html;
  });
  document.addEventListener('kodza:init', (event) => init(event.detail?.root));
  document.addEventListener('kodza:destroy', (event) => destroy(event.detail?.root));
  init();
  // Loaded in <head>, the script runs before the markup exists: once more when it is parsed
  if (document.readyState === 'loading') document.addEventListener('DOMContentLoaded', () => init(), { once: true });
})();

'use client';
// Kodza — Zoom Lens, for React. From https://kodza.dev/components/zoom-lens/
// Kodza License: free to use, client work included. Not to resell or redistribute, ported or not: https://kodza.dev/docs/#print-license
// Next to this file: zoom-lens.css and zoom-lens.js, the component's CSS and JS from Kodza, as they are.
// Yours to edit: the markup is plain JSX below.
// The script changes this markup once React has rendered it (it adds layers, splits text, moves
// nodes), so React must not patch it afterwards. When a prop changes, the key gives React a fresh
// element: kodza:destroy stops the script on the old one, kodza:init starts it on the new one.
import { useRef, useEffect, type ComponentPropsWithoutRef, type ComponentRef, type CSSProperties } from 'react';
import './zoom-lens.css';

type Variant = "inside";

export type ZoomLensProps = Omit<ComponentPropsWithoutRef<'figure'>, "children" | "variant" | "vars" | "zoom"> & {
  /** Modifier class(es): .kodza-zoom--inside */
  variant?: Variant | Variant[];
  /** data-zoom on the root (default: 2.5) */
  zoom?: "2.5" | "2.2";
  /** Settings, as CSS variables on the root */
  vars?: {
    /** default: 180px */
    "--kz-zoom-lens"?: string | number;
    /** default: #ffffff */
    "--kz-zoom-ring"?: string | number;
    /** default: 14px */
    "--kz-zoom-radius"?: string | number;
    /** default: cubic-bezier(0.22, 1, 0.36, 1) */
    "--kz-zoom-ease"?: string | number;
  };
  className?: string;
};

export function ZoomLens({ variant, zoom = "2.5", vars, className, style, ...rest }: ZoomLensProps) {
  const ref = useRef<ComponentRef<'figure'>>(null);
  const classes = ["kodza-zoom", ...([] as string[]).concat(variant ?? []).map((v) => `kodza-zoom--${v}`), className].filter(Boolean).join(' ');
  // Everything the markup is made of: when it changes, React gets a fresh element (see the top)
  const key = JSON.stringify([classes, zoom, vars, style, rest]);

  // Starts the script on this element once React has rendered it, stops it when it goes
  useEffect(() => {
    const root = ref.current;
    let live = true;
    // @ts-ignore: a plain script, no types to find
    import('./zoom-lens.js').then(() => {
      if (live) document.dispatchEvent(new CustomEvent('kodza:init', { detail: { root } }));
    });
    return () => {
      live = false;
      document.dispatchEvent(new CustomEvent('kodza:destroy', { detail: { root } }));
    };
  }, [key]);

  return (
    <figure key={key} {...rest} className={classes} data-zoom={zoom} style={{ ...vars, ...style } as CSSProperties} ref={ref}>
      <img src="https://kodza.dev/media/kz-steps-1400.webp" data-zoom-src="https://kodza.dev/media/kz-steps-2400.webp" alt="Concrete steps climbing towards the light" width="1400" height="933" />
    </figure>
  );
}