Install
That writes one file:compositions/components/svg-stroke-trace.html.
Paste it into your composition
Opencompositions/components/svg-stroke-trace.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 |
|---|---|---|---|
path | M 92 328 C 178 142 292 138 366 276 C 430 396 500 414 558 262 C 622 94 724 112 786 274 C 836 406 894 376 930 194 | string | SVG path data for the authored mark. |
stroke_width | 12 | 2 to 32, step 1 | Width of the traced stroke in SVG viewBox units. |
accent | green | green, blue, violet | Color used by the trace and optional fill. |
exit | none | none, fade, up | Optional departure. Default none: the finished mark holds until the frame cuts. |
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:
<div
data-composition-id="svg-stroke-trace"
data-composition-src="compositions/components/svg-stroke-trace.html"
data-variable-values='{"path":"M 92 328 C 178 142 292 138 366 276 C 430 396 500 414 558 262 C 622 94 724 112 786 274 C 836 406 894 376 930 194","stroke_width":12,"accent":"green","exit":"none"}'
></div>
Source
svg-stroke-trace.html
svg-stroke-trace.html
<!doctype html>
<!--
svg-stroke-trace: HyperFrames video primitive (intros and reveals)
An authored SVG path draws from start to finish using its measured length.
Closed paths receive a restrained fill after the stroke completes. Open
paths remain stroke-only, which keeps signatures and waves clean.
Variables:
- path (string): SVG path data for the traced mark.
- stroke_width (number, default 12): stroke width in viewBox units.
- accent (green | blue | violet, default green): trace and fill color.
- exit (none | fade | up, default "none"): optional departure.
Envelope, fixed IN and OUT with elastic HOLD only:
IN_BASE = 1.85s, stroke draw followed by optional closed-path fill
HOLD = max(0, D - IN - OUT), one subtle vertical drift cycle
OUT_BASE = 0.45s departure when exit is fade or up, 0s when exit is
none (the default: the finished mark holds until the cut)
If D is shorter than IN_BASE + OUT_BASE, IN and OUT compress together.
The timeline is never time-scaled.
Mount contract: the runtime clones only this template. #root fills the host
box, establishes the container query basis, has no data-width or data-height,
and registers one paused timeline under the literal svg-stroke-trace key.
-->
<html
lang="en"
data-composition-id="svg-stroke-trace"
data-composition-duration="3.5"
data-composition-variables='[
{ "id": "path", "type": "string", "role": "content", "label": "Path", "description": "SVG path data for the authored mark.", "default": "M 92 328 C 178 142 292 138 366 276 C 430 396 500 414 558 262 C 622 94 724 112 786 274 C 836 406 894 376 930 194" },
{ "id": "stroke_width", "type": "number", "role": "style", "label": "Stroke width", "description": "Width of the traced stroke in SVG viewBox units.", "default": 12, "min": 2, "max": 32, "step": 1 },
{ "id": "accent", "type": "enum", "role": "style", "label": "Accent", "description": "Color used by the trace and optional fill.", "default": "green", "options": [{ "value": "green", "label": "Green" }, { "value": "blue", "label": "Blue" }, { "value": "violet", "label": "Violet" }] },
{ "id": "exit", "type": "enum", "role": "timing", "label": "Exit", "description": "Optional departure. Default none: the finished mark holds until the frame cuts.", "default": "none", "options": [{ "value": "none", "label": "None" }, { "value": "fade", "label": "Fade" }, { "value": "up", "label": "Up" }] }
]'
>
<head>
<meta charset="UTF-8" />
<title>SVG Stroke Trace</title>
</head>
<body>
<template>
<div id="root" data-composition-id="svg-stroke-trace" data-duration="3.5" data-fps="30">
<style>
*,
*::before,
*::after {
box-sizing: border-box;
}
#root {
position: absolute;
inset: 0;
overflow: hidden;
container-type: size;
isolation: isolate;
pointer-events: none;
}
.sst-clip {
position: absolute;
inset: 0;
display: grid;
place-items: center;
overflow: hidden;
}
.sst-stage {
width: 88cqw;
height: 70cqh;
opacity: 0;
will-change: transform, opacity;
}
.sst-svg {
display: block;
width: 100%;
height: 100%;
overflow: visible;
}
.sst-fill,
.sst-stroke {
stroke-linecap: round;
stroke-linejoin: round;
}
.sst-fill {
fill: var(--sst-accent);
stroke: none;
opacity: 0;
}
.sst-stroke {
fill: none;
stroke: var(--sst-accent);
filter: drop-shadow(
0 0 1.8cqmin color-mix(in srgb, var(--sst-accent) 34%, transparent)
);
}
</style>
<div
id="svg-stroke-trace-clip"
class="sst-clip clip"
data-start="0"
data-duration="3.5"
data-track-index="0"
>
<div class="sst-stage" role="img">
<svg
class="sst-svg"
viewBox="0 0 1024 520"
preserveAspectRatio="xMidYMid meet"
aria-hidden="true"
>
<path class="sst-fill"></path>
<path class="sst-stroke"></path>
</svg>
</div>
</div>
<script src="https://cdn.jsdelivr.net/npm/gsap@3.14.2/dist/gsap.min.js"></script>
<script>
(function () {
"use strict";
var DEFAULT_PATH =
"M 92 328 C 178 142 292 138 366 276 C 430 396 500 414 558 262 C 622 94 724 112 786 274 C 836 406 894 376 930 194";
var root = document.getElementById("root");
var stage = root.querySelector(".sst-stage");
var fillPath = root.querySelector(".sst-fill");
var strokePath = root.querySelector(".sst-stroke");
var vars =
window.__hyperframes && window.__hyperframes.getVariables
? window.__hyperframes.getVariables()
: {};
var suppliedPath = vars.path == null ? DEFAULT_PATH : String(vars.path).trim();
var pathData = suppliedPath || DEFAULT_PATH;
var widthValue = vars.stroke_width;
var strokeWidth = Number.isFinite(widthValue)
? Math.max(2, Math.min(32, widthValue))
: 12;
var accentColors = {
green: "var(--brand, #71f5a7)",
blue: "var(--accent, #61a8ff)",
violet: "var(--accent-2, #c5a3ff)",
};
var accent = Object.prototype.hasOwnProperty.call(accentColors, vars.accent)
? vars.accent
: "green";
var exit = vars.exit === "fade" || vars.exit === "up" ? vars.exit : "none";
root.style.setProperty("--sst-accent", accentColors[accent]);
fillPath.setAttribute("d", pathData);
strokePath.setAttribute("d", pathData);
strokePath.setAttribute("stroke-width", String(strokeWidth));
stage.setAttribute("aria-label", "Authored SVG path tracing from start to finish");
var pathLength = strokePath.getTotalLength();
strokePath.style.strokeDasharray = pathLength + " " + pathLength;
strokePath.style.strokeDashoffset = String(pathLength);
// A trailing close command is the single owner of fill behavior.
// Open signatures and waves never receive an implied closing fill.
var fillEnabled = /[zZ]\s*$/.test(pathData);
var IN_BASE = 1.85;
var OUT_BASE = exit === "none" ? 0 : 0.45;
var DRAW_SHARE = 0.84;
var duration = Math.max(0.001, parseFloat(root.dataset.duration || "3.5"));
var fixedTotal = Math.max(0.001, IN_BASE + OUT_BASE);
var phaseScale = duration < fixedTotal ? duration / fixedTotal : 1;
var IN = IN_BASE * phaseScale;
var OUT = OUT_BASE * phaseScale;
var DRAW = IN * DRAW_SHARE;
var FILL = IN - DRAW;
var HOLD = Math.max(0, duration - IN - OUT);
var HOLD_START = IN;
var OUT_START = IN + HOLD;
var tl = gsap.timeline({ paused: true });
// IN: the path measurement owns both dash values, so every authored
// path draws exactly once regardless of its geometry.
tl.to(stage, { opacity: 1, duration: Math.min(0.28, DRAW), ease: "power2.out" }, 0);
tl.to(strokePath, { strokeDashoffset: 0, duration: DRAW, ease: "sine.inOut" }, 0);
if (fillEnabled) {
tl.to(fillPath, { opacity: 0.16, duration: FILL, ease: "power2.out" }, DRAW);
}
// HOLD: one finite drift cycle keeps longer mounts alive.
if (HOLD > 0) {
tl.to(
stage,
{
y: "-0.7cqh",
duration: HOLD / 2,
ease: "sine.inOut",
yoyo: true,
repeat: 1,
},
HOLD_START,
);
}
// OUT: optional departure; exit none holds until the frame cuts.
if (exit === "up") {
tl.to(
stage,
{ opacity: 0, y: "-2.4cqh", duration: OUT, ease: "power2.in" },
OUT_START,
);
} else if (exit === "fade") {
tl.to(stage, { opacity: 0, duration: OUT, ease: "power2.in" }, OUT_START);
}
tl.seek(0);
window.__timelines = window.__timelines || {};
window.__timelines["svg-stroke-trace"] = tl;
})();
</script>
</div>
</template>
</body>
</html>
motion-primitive intro reveal svg stroke line-draw.