> ## Documentation Index
> Fetch the complete documentation index at: https://hyperframes.heygen.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Light Sweep Pass

> A traveling key light re-shades a slotted scene: a soft diagonal gradient band crosses the frame once while every per-element highlight and shadow shifts in lockstep (all driven by one --light-x property), then the light settles into a resting key. Quiet, expensive-feeling; the scene itself never moves. Callers fill the named scene slot; a token hero-and-cards default renders when it is left empty.

export const InstallCommand = ({command}) => {
  const [copied, setCopied] = React.useState(false);
  const copy = async () => {
    try {
      if (navigator.clipboard && window.isSecureContext) {
        await navigator.clipboard.writeText(command);
      } else {
        const previous = document.activeElement;
        const scratch = document.createElement("textarea");
        scratch.value = command;
        scratch.setAttribute("readonly", "");
        scratch.style.position = "fixed";
        scratch.style.opacity = "0";
        document.body.appendChild(scratch);
        scratch.select();
        document.execCommand("copy");
        document.body.removeChild(scratch);
        previous?.focus?.();
      }
      setCopied(true);
      setTimeout(() => setCopied(false), 2000);
    } catch {}
  };
  return <div className="hf-install-command not-prose my-4 flex items-stretch overflow-hidden rounded-xl border border-zinc-200 bg-zinc-50 dark:border-zinc-800 dark:bg-zinc-900">
      <code className="flex-1 overflow-x-auto whitespace-nowrap border-r border-zinc-200 px-4 py-3 font-mono text-sm text-zinc-800 dark:border-zinc-800 dark:text-zinc-100">
        {command}
      </code>
      <button type="button" onClick={copy} data-copied={copied ? "true" : "false"} aria-label={`Copy ${command} to the clipboard`} className="hf-install-copy">
        <svg className="hf-install-copy-clipboard" xmlns="http://www.w3.org/2000/svg" width="16" height="16" viewBox="0 0 18 18" fill="none" stroke="currentColor" strokeWidth="1.5" strokeLinecap="round" strokeLinejoin="round" aria-hidden="true">
          <path d="M14.25 5.25H7.25C6.14543 5.25 5.25 6.14543 5.25 7.25V14.25C5.25 15.3546 6.14543 16.25 7.25 16.25H14.25C15.3546 16.25 16.25 15.3546 16.25 14.25V7.25C16.25 6.14543 15.3546 5.25 14.25 5.25Z" />
          <path d="M2.80103 11.998L1.77203 5.07397C1.61003 3.98097 2.36403 2.96397 3.45603 2.80197L10.38 1.77297C11.313 1.63397 12.19 2.16297 12.528 3.00097" />
        </svg>
        <svg className="hf-install-copy-check" xmlns="http://www.w3.org/2000/svg" width="16" height="16" viewBox="0 0 18 18" fill="none" stroke="currentColor" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round" aria-hidden="true">
          <path d="M2.75 9.5L6.5 13.25L15.25 4.5" />
        </svg>
      </button>
      <span className="hf-install-copy-status" role="status" aria-live="polite">
        {copied ? "Copied" : ""}
      </span>
    </div>;
};

<iframe className="w-full aspect-video rounded-xl border-0 bg-zinc-100 dark:bg-zinc-800" title="light-sweep-pass preview" loading="lazy" srcDoc={`<!doctype html><html><head><meta charset="utf-8"><style>html,body{margin:0;height:100%;overflow:hidden;background:transparent}hyperframes-player{display:block;width:100%;height:100%}</style><script src="https://cdn.jsdelivr.net/npm/@hyperframes/player@0.7/dist/hyperframes-player.global.js"><\/script></head><body><script>fetch("/public/catalog/components/light-sweep-pass.json").then(function(r){return r.json()}).then(function(d){var p=document.createElement("hyperframes-player");p.setAttribute("srcdoc",d.html);p.setAttribute("controls","");p.setAttribute("autoplay","");p.setAttribute("loop","");p.setAttribute("muted","");p.setAttribute("poster","https://static.heygen.ai/hyperframes-oss/docs/images/catalog/components/light-sweep-pass.png");document.body.appendChild(p)});<\/script></body></html>`} />

## Install

<InstallCommand command="npx hyperframes add light-sweep-pass" />

That writes one file: `compositions/components/light-sweep-pass.html`.

## Paste it into your composition

Open `compositions/components/light-sweep-pass.html` and copy what is inside into your own composition.

A component has no size or duration of its own. It takes both from the composition
you paste it into.

## Variables

Every one of these has a default, so the piece works untouched. Set the ones you
want to change on the element:

| Variable   | Default    | Accepts                    | What it does                                             |
| ---------- | ---------- | -------------------------- | -------------------------------------------------------- |
| `angle`    | `115`      | 60deg to 160deg, step 1deg | Band and highlight gradient angle in degrees.            |
| `sweep_at` | `0.9`      | 0s to 8s, step 0.05s       | Seconds after mount start when the band starts crossing. |
| `strength` | `standard` | `subtle`, `standard`       | Band opacity and highlight bloom multiplier.             |
| `accent`   | `green`    | `green`, `blue`, `violet`  | Tint inside the band and the highlight blooms.           |
| `exit`     | `none`     | `none`, `fade`, `up`       | Outgoing transition. None holds the settled key.         |

Set them with `data-variable-values` on the element that mounts it. These are the
defaults, so this behaves exactly like the preview above until you change one:

```html wrap theme={null}
<div
  data-composition-id="light-sweep-pass"
  data-composition-src="compositions/components/light-sweep-pass.html"
  data-variable-values='{"angle":115,"sweep_at":0.9,"strength":"standard","accent":"green","exit":"none"}'
></div>
```

## Source

<Accordion title={`light-sweep-pass.html`}>
  ```html theme={null}
  <!doctype html>
  <!--
    light-sweep-pass: HyperFrames video primitive (overlays / light)

    Concept: a traveling key light re-shades a slotted scene. A soft diagonal
    gradient band crosses the frame once while every per-element highlight and
    shadow shifts in lockstep, then the light settles into a resting key from
    the upper third. Quiet, expensive-feeling; the scene itself never moves.

    Wave L, unit L3. Reference: motion-reference/ordinaryfolkco
    2001090228958752945 (the traveling light band re-shading the frame).

    ONE PROPERTY OWNS THE PASS: --light-x (a unitless 0-100-ish scalar on
    #root) is the only animated value. The band's translate, every element's
    highlight bloom, every shadow offset, and the ambient lift all read it
    through calc()/clamp()/max() in static CSS. The timeline tweens a plain
    JS number proxy and writes --light-x in onUpdate (never a var() string),
    so seeks in any order resolve the same computed styles.

    Slot (see README.md for a worked example):
      - [data-slot="scene"]: the full-bleed scene being lit. Replace the
        children of this element in your installed copy. Default: a token
        hero card and three feature cards. Elements opt into the light with
        the data-lit attribute plus an inline --lsp-x (their center along
        the sweep axis, percent of frame width).

    Variables (declared in data-composition-variables below):
      - angle (number, degrees, default 115, 60 to 160): band and highlight
        gradient angle. 115 reads as upper-left key light.
      - sweep_at (number, seconds, default 0.9): when the band starts
        crossing, relative to mount start.
      - strength (subtle | standard, default standard): band opacity and
        highlight bloom multiplier. subtle is the barely-there pass.
      - accent (green | blue | violet, default green): warm tint inside the
        band and the highlight blooms. green maps to --brand, blue to
        --accent, violet to --accent-2.
      - exit (none | fade | up, default none): outgoing transition. none
        holds the settled key (frame roots own transitions).

    Envelope (fixed IN/OUT, elastic HOLD only, never gsap.timeScale()):
      IN       = sweep_at + 1.60s crossing + 0.55s settle to the resting key
      HOLD     = elastic = max(0, D - (IN + OUT)); the settled key is still
      OUT      = 0.50s when exit is fade or up, 0 when exit is none
      If D < IN + OUT, IN and OUT scale down together so IN + OUT == D.

    Sync point: sweep-land when the light reaches its resting key (3.05s at
    defaults). Dispatches a bubbling hf:sfx CustomEvent with id
    "light-settle-soft" there. This primitive never plays audio.

    Mount contract: MOUNTABLE SUB-COMPOSITION. The runtime clones only
    <template> contents; #root fills the host box (inset:0, container-type:
    size), has no data-width/data-height, and registers one paused timeline
    under the literal "light-sweep-pass" key. Variables come from
    window.__hyperframes.getVariables().
  -->
  <html
    lang="en"
    data-composition-id="light-sweep-pass"
    data-composition-duration="4"
    data-composition-variables='[
      { "id": "angle", "type": "number", "role": "style", "label": "Angle", "description": "Band and highlight gradient angle in degrees.", "default": 115, "min": 60, "max": 160, "step": 1, "unit": "deg" },
      { "id": "sweep_at", "type": "number", "role": "timing", "label": "Sweep start", "description": "Seconds after mount start when the band starts crossing.", "default": 0.9, "min": 0, "max": 8, "step": 0.05, "unit": "s" },
      { "id": "strength", "type": "enum", "role": "style", "label": "Strength", "description": "Band opacity and highlight bloom multiplier.", "default": "standard", "options": [{ "value": "subtle", "label": "Subtle" }, { "value": "standard", "label": "Standard" }] },
      { "id": "accent", "type": "enum", "role": "style", "label": "Accent", "description": "Tint inside the band and the highlight blooms.", "default": "green", "options": [{ "value": "green", "label": "Green" }, { "value": "blue", "label": "Blue" }, { "value": "violet", "label": "Violet" }] },
      { "id": "exit", "type": "enum", "role": "timing", "label": "Exit", "description": "Outgoing transition. None holds the settled key.", "default": "none", "options": [{ "value": "none", "label": "None" }, { "value": "fade", "label": "Fade" }, { "value": "up", "label": "Up" }] }
    ]'
  >
    <head>
      <meta charset="UTF-8" />
      <title>Light Sweep Pass</title>
    </head>
    <body>
      <template>
        <div id="root" data-composition-id="light-sweep-pass" data-duration="4" data-fps="30">
          <style>
            *,
            *::before,
            *::after {
              box-sizing: border-box;
            }

            /* --light-x starts off-frame left; the timeline is its only
               writer. --lsp-angle and --lsp-strength are set once at mount. */
            #root {
              --light-x: -35;
              --lsp-angle: 115;
              --lsp-strength: 1;
              position: absolute;
              inset: 0;
              container-type: size;
              isolation: isolate;
              overflow: hidden;
              background: var(--bg, #0b0c0e);
              color: var(--fg, #f8fafc);
              font-family: var(--font-body, Inter, system-ui, sans-serif);
            }

            .lsp-clip,
            .lsp-stage,
            .lsp-scene,
            .lsp-ambient,
            .lsp-band {
              position: absolute;
              inset: 0;
            }

            .lsp-clip {
              overflow: hidden;
            }

            .lsp-stage {
              opacity: 0;
            }

            .lsp-scene {
              overflow: hidden;
            }

            /* Every lit element derives its whole treatment from the ONE
               --light-x scalar: distance d to the band, |d| via max(d, -d),
               a 0..1 proximity bloom, a shadow that slides away from the
               light and deepens as the band passes. Elements opt in with
               data-lit and an inline --lsp-x (center along the sweep axis,
               percent of frame width). */
            [data-lit] {
              --lsp-d: calc(var(--light-x) - var(--lsp-x, 50));
              --lsp-abs: max(var(--lsp-d), calc(-1 * var(--lsp-d)));
              --lsp-glow: clamp(0, calc(1 - var(--lsp-abs) / 26), 1);
              position: relative;
              box-shadow: calc(clamp(-30, var(--lsp-d), 30) * -0.05cqw)
                calc(0.8cqh + var(--lsp-glow) * 0.7cqh) calc(2.2cqh + var(--lsp-glow) * 2.4cqh)
                color-mix(in srgb, #000000 26%, transparent);
            }

            /* The highlight bloom: a static angle-matched gradient whose
               opacity is the proximity term. No transitions, no tweens. */
            [data-lit]::after {
              content: "";
              position: absolute;
              inset: 0;
              border-radius: inherit;
              pointer-events: none;
              background: linear-gradient(
                calc(var(--lsp-angle) * 1deg),
                color-mix(in srgb, #ffffff 86%, var(--lsp-accent, #22c55e)) 0%,
                transparent 62%
              );
              opacity: calc(var(--lsp-glow) * 0.32 * var(--lsp-strength));
            }

            /* Ambient lift: the scene starts a touch dim and brightens for
               good once the band has entered the frame. Monotonic in
               --light-x, so the settle never re-dims it. */
            .lsp-ambient {
              pointer-events: none;
              background: #000000;
              opacity: calc(clamp(0, (26 - var(--light-x)) / 130, 0.16) * var(--lsp-strength));
            }

            /* The band: an oversized angle-matched gradient sheet that only
               ever translates along X, driven by the same scalar. Screen
               blend keeps it a light, never a paint. */
            .lsp-band {
              inset: -55%;
              pointer-events: none;
              mix-blend-mode: screen;
              background: linear-gradient(
                calc(var(--lsp-angle) * 1deg),
                transparent 36%,
                color-mix(in srgb, #ffffff 24%, transparent) 46%,
                color-mix(in srgb, #ffffff 78%, var(--lsp-accent, #22c55e)) 50%,
                color-mix(in srgb, #ffffff 24%, transparent) 54%,
                transparent 64%
              );
              opacity: 0;
              transform: translateX(calc((var(--light-x) - 50) * 1.4cqw));
              will-change: transform, opacity;
            }

            #root[data-strength="subtle"] {
              --lsp-strength: 0.55;
            }

            /* ---------- default slot scene: token hero + three cards ---------- */

            .lsp-default {
              position: absolute;
              inset: 0;
              display: grid;
              grid-template-rows: auto auto;
              align-content: center;
              justify-items: center;
              row-gap: var(--space-3, 5cqh);
              padding: var(--space-3, 6cqh) 10cqw;
              background: linear-gradient(
                calc(var(--lsp-angle) * 1deg),
                color-mix(in srgb, var(--fg, #f8fafc) 3%, var(--bg, #0b0c0e)) 0%,
                var(--bg, #0b0c0e) 55%,
                color-mix(in srgb, #000000 6%, var(--bg, #0b0c0e)) 100%
              );
            }

            .lsp-hero {
              display: grid;
              align-content: center;
              row-gap: var(--space-2, 2.4cqh);
              width: 58cqw;
              height: 30cqh;
              padding: var(--space-3, 4cqh) var(--space-3, 3cqw);
              border: 0.16cqw solid var(--border, #343a46);
              border-radius: var(--radius, 2.4cqmin);
              background: var(--surface, #14171c);
            }

            .lsp-hero-bar {
              width: 46%;
              height: 4.6cqh;
              border-radius: 1.4cqh;
              background: color-mix(in srgb, var(--fg, #f8fafc) 82%, var(--surface, #14171c));
            }

            .lsp-hero-line {
              height: 2.2cqh;
              border-radius: 1.1cqh;
              background: var(--muted, #94a3b8);
              opacity: 0.55;
            }

            .lsp-hero-line:nth-of-type(3) {
              width: 72%;
            }

            .lsp-row {
              display: grid;
              grid-template-columns: repeat(3, 1fr);
              column-gap: var(--space-2, 2cqw);
              width: 58cqw;
            }

            .lsp-card {
              display: grid;
              align-content: start;
              row-gap: var(--space-1, 1.6cqh);
              height: 24cqh;
              padding: var(--space-2, 2.6cqh) var(--space-2, 1.6cqw);
              border: 0.16cqw solid var(--border, #343a46);
              border-radius: var(--radius, 2.4cqmin);
              background: var(--surface, #14171c);
            }

            .lsp-dot {
              width: 3.4cqh;
              height: 3.4cqh;
              border-radius: 50%;
              background: color-mix(in srgb, var(--lsp-accent, #22c55e) 72%, var(--surface, #14171c));
            }

            .lsp-line {
              height: 1.9cqh;
              border-radius: 1cqh;
              background: var(--muted, #94a3b8);
              opacity: 0.5;
            }

            .lsp-line:nth-of-type(3) {
              width: 64%;
            }
          </style>

          <div
            id="light-sweep-pass-clip"
            class="lsp-clip clip"
            data-start="0"
            data-duration="4"
            data-track-index="0"
          >
            <div class="lsp-stage">
              <div class="lsp-scene" data-slot="scene">
                <!-- SLOT "scene": replace the children of this element with
                     your own full-bleed content. Mark elements that should
                     catch the light with data-lit and give each an inline
                     style="--lsp-x: NN" (center along the sweep, percent). -->
                <div class="lsp-default" aria-hidden="true">
                  <div class="lsp-hero" data-lit style="--lsp-x: 50">
                    <div class="lsp-hero-bar"></div>
                    <div class="lsp-hero-line"></div>
                    <div class="lsp-hero-line"></div>
                  </div>
                  <div class="lsp-row">
                    <div class="lsp-card" data-lit style="--lsp-x: 31">
                      <div class="lsp-dot"></div>
                      <div class="lsp-line"></div>
                      <div class="lsp-line"></div>
                    </div>
                    <div class="lsp-card" data-lit style="--lsp-x: 50">
                      <div class="lsp-dot"></div>
                      <div class="lsp-line"></div>
                      <div class="lsp-line"></div>
                    </div>
                    <div class="lsp-card" data-lit style="--lsp-x: 69">
                      <div class="lsp-dot"></div>
                      <div class="lsp-line"></div>
                      <div class="lsp-line"></div>
                    </div>
                  </div>
                </div>
              </div>
              <div class="lsp-ambient" aria-hidden="true"></div>
              <div class="lsp-band" aria-hidden="true"></div>
            </div>
          </div>

          <script src="https://cdn.jsdelivr.net/npm/gsap@3.14.2/dist/gsap.min.js"></script>
          <script>
            (function () {
              "use strict";

              var root = document.getElementById("root");
              // Literal id: mount flattening strips data-composition-id from the
              // live root before this timeline registers.
              var compositionId = "light-sweep-pass";
              var stage = root.querySelector(".lsp-stage");
              var band = root.querySelector(".lsp-band");

              var vars =
                window.__hyperframes && window.__hyperframes.getVariables
                  ? window.__hyperframes.getVariables()
                  : {};

              function clampNumber(raw, fallback, min, max) {
                var value = raw == null ? fallback : Number(raw);
                if (!Number.isFinite(value)) return fallback;
                return Math.max(min, Math.min(max, value));
              }

              var angle = clampNumber(vars.angle, 115, 60, 160);
              var sweepAt = clampNumber(vars.sweep_at, 0.9, 0, 8);
              var strength = vars.strength === "subtle" ? "subtle" : "standard";
              var accentTokens = {
                green: "var(--brand, #22c55e)",
                blue: "var(--accent, #38bdf8)",
                violet: "var(--accent-2, #c5a3ff)",
              };
              var accent = Object.prototype.hasOwnProperty.call(accentTokens, vars.accent)
                ? vars.accent
                : "green";
              // The bundler mirrors composition variables as scoped CSS custom
              // props, so this unit's own accent variable can shadow the contract
              // --accent token ("blue" is a valid CSS color). When the shadow is
              // present, fall back to the literal contract value.
              var shadowedAccent = getComputedStyle(root).getPropertyValue("--accent").trim();
              if (
                shadowedAccent === "green" ||
                shadowedAccent === "blue" ||
                shadowedAccent === "violet"
              ) {
                accentTokens.blue = "#38bdf8";
              }
              // INVARIANT: only none | fade | up reaches the timeline.
              var exit = vars.exit === "fade" || vars.exit === "up" ? vars.exit : "none";

              root.dataset.strength = strength;
              root.style.setProperty("--lsp-angle", String(angle));
              root.style.setProperty("--lsp-accent", accentTokens[accent]);

              // RETIME RANGE: fixed IN and OUT scale together only when D is
              // too short. HOLD is the sole elastic phase. Never timeScale().
              var SWEEP_BASE = 1.6;
              var SETTLE_BASE = 0.55;
              var STAGE_IN_BASE = 0.5;
              var IN_BASE = sweepAt + SWEEP_BASE + SETTLE_BASE;
              var OUT_BASE = exit === "none" ? 0 : 0.5;

              var duration = Math.max(0.001, parseFloat(root.dataset.duration || "4"));
              var totalBase = IN_BASE + OUT_BASE;
              var scale = duration < totalBase ? duration / totalBase : 1;
              var SWEEP = SWEEP_BASE * scale;
              var SETTLE = SETTLE_BASE * scale;
              var STAGE_IN = Math.min(STAGE_IN_BASE * scale, IN_BASE * scale);
              var SWEEP_AT = sweepAt * scale;
              var SWEEP_END = SWEEP_AT + SWEEP;
              var IN = IN_BASE * scale;
              var OUT = OUT_BASE * scale;
              var HOLD = Math.max(0, duration - (IN + OUT));
              var OUT_START = IN + HOLD;

              // The light's authored waypoints: parked off-frame left, fully
              // crossed off-frame right, then the resting key in the upper
              // third of the travel. All in --light-x units (frame percent).
              var LIGHT_START = -35;
              var LIGHT_CROSSED = 118;
              var LIGHT_REST = 62;

              function fireSfx(id, t) {
                root.dispatchEvent(
                  new CustomEvent("hf:sfx", { detail: { id: id, t: t }, bubbles: true }),
                );
              }

              // ONE proxy owns --light-x; every highlight, shadow, ambient
              // lift, and the band transform read it via calc in static CSS.
              var light = { x: LIGHT_START };
              function writeLight() {
                root.style.setProperty("--light-x", light.x.toFixed(3));
              }
              writeLight();

              gsap.set(stage, { opacity: 0, y: "1.5cqh" });
              gsap.set(band, { autoAlpha: 0 });

              var tl = gsap.timeline({ paused: true });

              // IN: the scene settles first, then one confident crossing.
              tl.to(stage, { opacity: 1, y: "0cqh", duration: STAGE_IN, ease: "power2.out" }, 0);
              tl.fromTo(
                light,
                { x: LIGHT_START },
                {
                  x: LIGHT_CROSSED,
                  duration: SWEEP,
                  ease: "sine.inOut",
                  onUpdate: writeLight,
                },
                SWEEP_AT,
              );
              tl.fromTo(
                band,
                { autoAlpha: 0 },
                {
                  autoAlpha: 1,
                  duration: Math.min(0.3 * scale, SWEEP),
                  ease: "power1.out",
                  immediateRender: false,
                },
                SWEEP_AT,
              );
              tl.to(
                band,
                { autoAlpha: 0, duration: 0.35 * scale, ease: "power1.in" },
                Math.max(SWEEP_AT, SWEEP_END - 0.35 * scale),
              );

              // The settle: the band is gone; the key light glides back to its
              // resting position and the per-element shading follows it there.
              tl.to(
                light,
                { x: LIGHT_REST, duration: SETTLE, ease: "power2.out", onUpdate: writeLight },
                SWEEP_END,
              );
              tl.call(
                function () {
                  fireSfx("light-settle-soft", IN);
                },
                [],
                IN,
              );

              // HOLD: deliberately still under the settled key.

              // OUT: only when the exit variable asks for one.
              if (exit !== "none") {
                tl.to(stage, { opacity: 0, duration: OUT, ease: "power2.in" }, OUT_START);
                if (exit === "up") {
                  tl.to(stage, { y: "-6cqh", duration: OUT, ease: "power2.in" }, OUT_START);
                }
              }

              tl.seek(0);

              window.__timelines = window.__timelines || {};
              window.__timelines[compositionId] = tl;
            })();
          </script>
        </div>
      </template>
    </body>
  </html>
  ```
</Accordion>

Tagged `motion-primitive` `overlay` `light` `sweep` `slots` `deterministic`.

## Related topics

* [Browse the complete Catalog](/catalog)
* [Add assets and Catalog items in Studio](/studio/assets-and-blocks)
* [Build a richer composition](/go-further)


## Related topics

- [Shimmer Sweep](/catalog/components/shimmer-sweep.md)
- [VFX and liquid glass](/prompting/vfx-and-liquid-glass.md)
- [Word-Sweep Highlight](/catalog/blocks/mk-callout-highlight.md)
