Install
That writescompositions/weight-wave.html, plus 2 supporting files under compositions/assets/fonts/.
Add it to your video
It runs for 6 seconds at 1920×1080. Paste this into your composition:index.html
<div
data-composition-id="weight-wave"
data-composition-src="compositions/weight-wave.html"
data-start="0"
data-duration="6"
data-track-index="1"
data-width="1920"
data-height="1080"
></div>
data-start. Put it on a different timeline row with
data-track-index. See data attributes for the rest.
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 |
|---|---|---|---|
text | PRESSURE MOVES THROUGH TYPE | string | |
color | #f5f5f7 | color | |
background | #0b0b0d | color | |
weightFrom | 400 | 300 to 1000, step 10 | |
weightTo | 1000 | 300 to 1000, step 10 | |
crestWidth | 4 | 1chars to 24chars, step 0.5chars | |
sweepSpeed | 0.5 | 0.05passes/s to 3passes/s, step 0.05passes/s | |
slant | -12 | -15deg to 0deg, step 0.5deg | |
direction | ltr | ltr, rtl |
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="weight-wave"
data-composition-src="compositions/weight-wave.html"
data-variable-values='{"text":"PRESSURE MOVES THROUGH TYPE","color":"#f5f5f7","background":"#0b0b0d","weightFrom":400,"weightTo":1000,"crestWidth":4,"sweepSpeed":0.5,"slant":-12,"direction":"ltr"}'
></div>
Source
weight-wave.html
weight-wave.html
<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8" />
<meta name="viewport" content="width=1920, height=1080" />
<title>Weight Wave</title>
<style>
/*
Real variable font, bundled locally — a CDN fetch would be a render-time
network dependency, and a STATIC font would silently render every
character at one weight (the whole effect vanishes while nothing errors).
Subset of Recursive (SIL OFL 1.1) with every axis pinned except the two
this block drives. Ranges below are the font's REAL fvar records, read
out of the binary: wght 300..1000 (not 100..900) and slnt -15..0. The
pinned three are MONO 0 (proportional sans, not the monospace face),
CASL 0 (linear/neutral, not casual) and CRSV 0 (roman letterforms —
Recursive's 0.5 default swaps in cursive singlestorey forms as soon as
slnt goes negative, which would pop mid-wave instead of interpolating).
*/
@font-face {
font-family: "Recursive Wave";
font-style: normal;
font-weight: 300 1000;
font-display: block;
src: url("assets/fonts/Recursive-wght-slnt-latin.woff2") format("woff2");
}
</style>
<script src="https://cdn.jsdelivr.net/npm/gsap@3.14.2/dist/gsap.min.js"></script>
<style>
*,
*::before,
*::after {
margin: 0;
padding: 0;
box-sizing: border-box;
}
html,
body {
background: transparent;
overflow: hidden;
}
body {
width: 1920px;
height: 1080px;
}
#ww-root {
position: relative;
width: 1920px;
height: 1080px;
overflow: hidden;
}
/* Full-bleed fill lives on a CHILD: the producer can drop a background
painted on the composition root itself (frame renders black). */
#ww-bg {
position: absolute;
inset: 0;
background: var(--background, #0b0b0d);
}
#ww-stage {
position: absolute;
inset: 0;
display: flex;
align-items: center;
justify-content: center;
}
#ww-line {
display: block;
width: 1760px;
text-align: center;
white-space: pre;
font-family: "Recursive Wave", sans-serif;
font-size: 132px;
line-height: 1.15;
letter-spacing: 0.005em;
color: var(--color, #f5f5f7);
/* Default instance: the resting end of the wave. If the variable font
fails to load, every glyph stays here and the probe below shouts. */
font-variation-settings:
"wght" 400,
"slnt" 0;
}
/* Per-character axis stamping target: no transform, no opacity — the
letterforms themselves change. */
.ww-ch {
display: inline-block;
}
</style>
</head>
<body>
<div
id="ww-root"
data-composition-id="weight-wave"
data-start="0"
data-duration="6"
data-width="1920"
data-height="1080"
data-composition-variables='[
{"id":"text","type":"string","label":"Headline","default":"PRESSURE MOVES THROUGH TYPE","maxLength":64},
{"id":"color","type":"color","label":"Text color","default":"#f5f5f7"},
{"id":"background","type":"color","label":"Background","default":"#0b0b0d"},
{"id":"weightFrom","type":"number","label":"Weight (rest)","default":400,"min":300,"max":1000,"step":10},
{"id":"weightTo","type":"number","label":"Weight (crest)","default":1000,"min":300,"max":1000,"step":10},
{"id":"crestWidth","type":"number","label":"Crest width","default":4,"min":1,"max":24,"step":0.5,"unit":"chars"},
{"id":"sweepSpeed","type":"number","label":"Sweep speed","default":0.5,"min":0.05,"max":3,"step":0.05,"unit":"passes/s"},
{"id":"slant","type":"number","label":"Slant at crest","default":-12,"min":-15,"max":0,"step":0.5,"unit":"deg"},
{"id":"direction","type":"enum","label":"Direction","default":"ltr","options":[{"value":"ltr","label":"Left to right"},{"value":"rtl","label":"Right to left"}]}
]'
>
<div id="ww-bg"></div>
<div id="ww-stage" class="clip" data-start="0" data-duration="6" data-track-index="0">
<div id="ww-line"></div>
</div>
<script>
(function () {
window.__timelines = window.__timelines || {};
var FONT_FAMILY = '"Recursive Wave", sans-serif';
/* The bundled font's real fvar bounds — declared once here, and
mirrored in the variable min/max above. A slider must not offer a
weight the font cannot render. */
var WGHT_MIN = 300;
var WGHT_MAX = 1000;
var SLNT_MIN = -15;
var LINE_MAX_WIDTH = 1760;
var BASE_FONT_SIZE = 132;
var MIN_FONT_SIZE = 40;
var root = document.getElementById("ww-root");
var line = document.getElementById("ww-line");
var duration = Number(root.getAttribute("data-duration")) || 6;
var vars =
window.__hyperframes && window.__hyperframes.getVariables
? window.__hyperframes.getVariables()
: {};
function num(value, fallback, min, max) {
var n = Number(value);
if (!Number.isFinite(n)) n = fallback;
return Math.min(max, Math.max(min, n));
}
var TEXT =
typeof vars.text === "string" && vars.text.length
? vars.text
: "PRESSURE MOVES THROUGH TYPE";
var W_FROM = num(vars.weightFrom, 400, WGHT_MIN, WGHT_MAX);
var W_TO = num(vars.weightTo, 1000, WGHT_MIN, WGHT_MAX);
var CREST = num(vars.crestWidth, 4, 1, 24);
var SPEED = num(vars.sweepSpeed, 0.5, 0.05, 3);
var SLANT = num(vars.slant, -12, SLNT_MIN, 0);
var RTL = vars.direction === "rtl";
/* ── Build one span per character ─────────────────────────────────
Spaces get a span too, so the crest travels at a constant rate in
index space and the visual gap between words is honoured. */
var chars = Array.prototype.slice.call(TEXT);
var spans = chars.map(function (ch) {
var el = document.createElement("span");
el.className = "ww-ch";
el.textContent = ch;
line.appendChild(el);
return el;
});
var N = spans.length;
/* Fit at the HEAVIEST instance so the line never overflows mid-sweep;
the crest widens glyphs as it passes. */
var fitCanvas = document.createElement("canvas").getContext("2d");
var heaviest = Math.max(W_FROM, W_TO);
var fontSize = BASE_FONT_SIZE;
while (fontSize > MIN_FONT_SIZE) {
fitCanvas.font = heaviest + " " + fontSize + "px " + FONT_FAMILY;
if (fitCanvas.measureText(TEXT).width <= LINE_MAX_WIDTH) break;
fontSize -= 2;
}
line.style.fontSize = fontSize + "px";
/* ── The wave ─────────────────────────────────────────────────────
Closed form, no accumulators: every frame's state is a pure
function of the timeline position p, so a direct seek to frame N
and playing through to frame N produce identical pixels.
crest(p) = -CREST + wrap(p * duration * SPEED) * (N - 1 + 2*CREST)
f_i = clamp(0, 1, 1 - |i - crest| / CREST)
wght_i = round(lerp(W_FROM, W_TO, f_i))
slnt_i = lerp(0, SLANT, f_i)
Per-character stagger is not a separate mechanism — it falls out of
the crest's distance to each index. */
var state = { p: 0 };
var travel = N - 1 + 2 * CREST;
function paint() {
var pass = state.p * duration * SPEED;
var phase = pass - Math.floor(pass); // wraps cleanly: f_i == 0 at both ends
var crest = -CREST + phase * travel;
if (RTL) crest = N - 1 - crest;
for (var i = 0; i < N; i++) {
var f = 1 - Math.abs(i - crest) / CREST;
if (f < 0) f = 0;
else if (f > 1) f = 1;
var wght = Math.round(W_FROM + (W_TO - W_FROM) * f);
var slnt = SLANT * f;
spans[i].style.fontVariationSettings =
'"wght" ' + wght + ', "slnt" ' + slnt.toFixed(2);
}
}
var tl = gsap.timeline({ paused: true });
tl.to(state, { p: 1, duration: duration, ease: "none", onUpdate: paint }, 0);
paint();
window.__timelines["weight-wave"] = tl;
/* ── The trap, made loud ──────────────────────────────────────────
A static font (or a failed load) renders every character at one
weight: the effect is invisible and nothing throws.
Measuring advance width does NOT detect that here. Recursive is
DUPLEXED — "HAMBURGEFONSTIV" measures exactly 925px at wght 300 and
at wght 1000, and identically at slnt 0 and -15. (Nice for layout:
the headline never reflows as the crest passes. Fatal for a
width-delta probe, which reads every weight as identical and cries
wolf on a perfectly healthy font.)
So rasterize and count ink, which cannot be duplexed away, AND ask
the font-loading API whether the family is actually there. Both are
needed: ink alone gives a false PASS when the family is missing,
because the fallback varies its ink with weight too. */
function probeAxes() {
var family = "Recursive Wave";
var loaded = !!(document.fonts && document.fonts.check('100px "' + family + '"'));
var c = document.createElement("canvas");
c.width = 1000;
c.height = 160;
var ctx = c.getContext("2d", { willReadFrequently: true });
function ink(weight) {
ctx.clearRect(0, 0, c.width, c.height);
ctx.font = weight + ' 100px "' + family + '"';
ctx.fillStyle = "#fff";
ctx.fillText("HAMBURGEFONSTIV", 10, 120);
var data = ctx.getImageData(0, 0, c.width, c.height).data;
var n = 0;
for (var i = 3; i < data.length; i += 4) if (data[i] > 8) n++;
return n;
}
var light = ink(WGHT_MIN);
var black = ink(WGHT_MAX);
// Only wght is probed: it is the axis whose absence is measurable
// from JS, and both axes ship in the same file — if wght is live,
// the variable font loaded. slnt is verified visually.
return {
fontLoaded: loaded,
wghtLive: black > light * 1.2,
inkAtMinWeight: light,
inkAtMaxWeight: black,
};
}
function publishProbe() {
var status = probeAxes();
status.ok = status.fontLoaded && status.wghtLive;
window.__WW_FONT_STATUS = status;
root.setAttribute("data-ww-font", status.ok ? "ok" : "missing-axes");
if (!status.ok) {
console.error(
"weight-wave: the variable font is not usable (loaded=" +
status.fontLoaded +
", ink at wght " +
WGHT_MIN +
"=" +
status.inkAtMinWeight +
" vs " +
WGHT_MAX +
"=" +
status.inkAtMaxWeight +
"). assets/fonts/Recursive-wght-slnt-latin.woff2 did not load, or was " +
"replaced with a static font — every character will render at one weight.",
);
}
}
if (document.fonts && document.fonts.ready) {
document.fonts.ready.then(publishProbe);
} else {
publishProbe();
}
})();
</script>
</div>
</body>
</html>
typography kinetic-type title variable-font text.