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

# Soft Blob Touch

> A granular soft blob idles with slow internal drift; a scripted touch dot decel-arrives, the blob deforms toward it with an attraction bulge, then recovers with a velocity-preserving spring. No hard edges anywhere.

# Soft Blob Touch

A granular soft blob idles with slow internal drift; a scripted touch dot decel-arrives, the blob deforms toward it with an attraction bulge, then recovers with a velocity-preserving spring. No hard edges anywhere.

**Soft Blob Touch**

```html soft-blob-touch.html theme={null}
<!doctype html>
<!--
  soft-blob-touch: HyperFrames video primitive (product demo / material)

  A granular soft blob idles with slow internal drift; a scripted touch dot
  decel-arrives at a caller-positioned point; the blob deforms toward it
  (an attraction bulge with mass), then recovers with an interruptible
  spring once the dot retreats. The AI-orb material beat. Softness is the
  whole point: the body is layered radial gradients plus a seeded grain
  field, and nothing in the frame has a hard edge.

  Reference: alexwidua 1702356241186476225 sheet-02 (granular blob leaning
  toward a finger; fuzzy boundary, mass, recovery wobble).

  Variables (declared in data-composition-variables below):
    - touch_x, touch_y (numbers, percent of host box): where the dot lands.
    - touch_at (seconds): when the dot makes contact. Clamped so the whole
      deform and recover tail stays inside the clip.
    - grain ("fine" | "coarse"): speck count and size for the body.
    - accent ("green" | "blue" | "violet"): green rides --brand, blue rides
      --accent, violet rides --accent-2.
    - exit ("none" | "fade" | "up"): default none, the settled blob holds.

  Envelope, fixed IN and OUT with elastic HOLD only (never timeScale):
    IN ends when the recovery spring settles (touch_at + 1.57s); HOLD is
    dead still (drift completes integer sine cycles and ends at exactly
    zero by then); OUT = 0.45s only when exit is not none.

  Deformation model (law L1, interruptible spring):
    Two plain-object params (bulge, lean) feed ONE onUpdate painter. The
    attack tween is the first 75 percent of a power2.out lean-in, cut
    mid-flight when the dot lifts (analytic cut: the junction value AND
    velocity are computed in closed form). The recovery tween's ease is a
    closed-form underdamped spring whose initial velocity equals the cut
    velocity, so the redirect preserves momentum exactly. Both tweens have
    explicit endpoints; any seek order lands identical values.

  Determinism (canvas 2D law, per particle-image-reveal):
    One grain table is computed exactly once at build from fixed LCG seed
    0x50f7b10b. Every painted frame is a pure function of (table, params,
    timeline time). onUpdate clears and redraws from scratch; no
    Math.random, no wall clock, no incremental state. Eventful seeks
    (suppressEvents false) repaint identically in any order.
-->
<html
  lang="en"
  data-composition-id="soft-blob-touch"
  data-composition-duration="4"
  data-composition-variables='[
    { "id": "touch_x", "type": "number", "role": "layout", "label": "Touch X", "description": "Touch point, percent of host width.", "default": 66, "min": 8, "max": 92, "step": 1, "unit": "%" },
    { "id": "touch_y", "type": "number", "role": "layout", "label": "Touch Y", "description": "Touch point, percent of host height.", "default": 38, "min": 8, "max": 92, "step": 1, "unit": "%" },
    { "id": "touch_at", "type": "number", "role": "timing", "label": "Touch at", "description": "Seconds from mount start when the dot makes contact.", "default": 1.6, "min": 0.9, "max": 10, "step": 0.1, "unit": "s" },
    { "id": "grain", "type": "enum", "role": "style", "label": "Grain", "description": "Speck register for the granular body.", "default": "fine", "options": [{ "value": "fine", "label": "Fine" }, { "value": "coarse", "label": "Coarse" }] },
    { "id": "accent", "type": "enum", "role": "style", "label": "Accent", "description": "Body tint: green rides --brand, blue rides --accent, violet rides --accent-2.", "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 settled blob 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>Soft Blob Touch</title>
  </head>
  <body>
    <template>
      <div id="root" data-composition-id="soft-blob-touch" data-duration="4" data-fps="30">
        <style>
          *,
          *::before,
          *::after {
            box-sizing: border-box;
          }

          #root {
            position: absolute;
            inset: 0;
            overflow: hidden;
            container-type: size;
            isolation: isolate;
            color: var(--fg, #f8fafc);
            font-family: var(--font-body, "Inter", system-ui, sans-serif);
            pointer-events: none;
          }

          .sbt-clip {
            position: absolute;
            inset: 0;
            overflow: hidden;
          }

          .sbt-stage {
            position: absolute;
            inset: 0;
            will-change: transform, opacity;
          }

          .sbt-canvas {
            position: absolute;
            inset: 0;
            width: 100%;
            height: 100%;
          }

          /* The touch dot: a soft disc with a gradient falloff, no hard rim.
             Motion rides transforms only (px), never left or top. */
          .sbt-touch {
            position: absolute;
            left: 0;
            top: 0;
            width: 4.6cqmin;
            height: 4.6cqmin;
            margin-left: -2.3cqmin;
            margin-top: -2.3cqmin;
            border-radius: 50%;
            background: radial-gradient(
              circle at 42% 38%,
              color-mix(in srgb, var(--fg, #f8fafc) 96%, transparent) 0%,
              color-mix(in srgb, var(--fg, #f8fafc) 78%, transparent) 34%,
              color-mix(in srgb, var(--fg, #f8fafc) 26%, transparent) 62%,
              transparent 78%
            );
            will-change: transform, opacity;
          }
        </style>

        <div
          id="soft-blob-touch-clip"
          class="sbt-clip clip"
          data-start="0"
          data-duration="4"
          data-track-index="0"
        >
          <div class="sbt-stage">
            <canvas class="sbt-canvas" aria-hidden="true"></canvas>
            <div class="sbt-touch" 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");
            var stage = root.querySelector(".sbt-stage");
            var canvas = root.querySelector(".sbt-canvas");
            var touchDot = root.querySelector(".sbt-touch");
            var vars =
              window.__hyperframes && window.__hyperframes.getVariables
                ? window.__hyperframes.getVariables()
                : {};

            function num(value, fallback, min, max) {
              var n = Number(value);
              if (!isFinite(n)) n = fallback;
              return Math.max(min, Math.min(max, n));
            }

            var grain = vars.grain === "coarse" ? "coarse" : "fine";
            var exit = vars.exit === "fade" || vars.exit === "up" ? vars.exit : "none";
            // Each enum choice routes to a DIFFERENT contract token so the
            // variable stays meaningful under a theme.
            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";
            // The bundler mirrors composition variables as scoped CSS custom
            // props, so this unit's own accent variable shadows the contract
            // --accent token inside the subtree ("blue" is a valid CSS color
            // and would render pure blue). When the shadow is present, fall
            // back to the literal contract value instead of var(--accent).
            var computedAccent = getComputedStyle(root).getPropertyValue("--accent").trim();
            if (
              computedAccent === "green" ||
              computedAccent === "blue" ||
              computedAccent === "violet"
            ) {
              accentColors.blue = "#61a8ff";
            }

            // Envelope. The deform tail is ATTACK + RECOVER after contact;
            // clamp touch_at so the spring settles inside the clip.
            var ATTACK_NAT = 0.55; // natural length of the uncut lean-in
            var CUT_FRAC = 0.75; // the dot lifts at 75 percent of it
            var ATTACK = ATTACK_NAT * CUT_FRAC;
            var RECOVER = 1.15;
            var duration = Math.max(0.001, parseFloat(root.dataset.duration || "4"));
            var OUT = exit === "none" ? 0 : 0.45;
            var maxTouch = Math.max(0.9, duration - (ATTACK + RECOVER) - OUT - 0.05);
            var touchAt = num(vars.touch_at, 1.6, 0.9, maxTouch);
            var cutAt = touchAt + ATTACK;
            var IN_END = cutAt + RECOVER;
            var OUT_START = IN_END + Math.max(0, duration - IN_END - OUT);

            // Canvas raster basis is fixed once at mount (elastic root: the
            // host box decides the resolution; same host, same raster).
            var dpr = Math.min(2, Math.max(1, Number(window.devicePixelRatio) || 1));
            var box = root.getBoundingClientRect();
            var cssW = Math.max(1, Math.round(box.width) || 640);
            var cssH = Math.max(1, Math.round(box.height) || 360);
            canvas.width = Math.round(cssW * dpr);
            canvas.height = Math.round(cssH * dpr);
            var ctx = canvas.getContext("2d");
            var W = canvas.width;
            var H = canvas.height;
            var minDim = Math.min(W, H);

            var touchX = (num(vars.touch_x, 66, 8, 92) / 100) * W;
            var touchY = (num(vars.touch_y, 38, 8, 92) / 100) * H;
            var centerX = W * 0.5;
            var centerY = H * 0.5;
            var R = minDim * 0.26;

            // Direction of attraction, guarded for a touch at dead center.
            var dxT = touchX - centerX;
            var dyT = touchY - centerY;
            var distT = Math.hypot(dxT, dyT);
            var dirX = distT > 1 ? dxT / distT : 0.7071;
            var dirY = distT > 1 ? dyT / distT : -0.7071;

            // Resolve accent and fg to concrete rgb once at mount so canvas
            // fills never depend on style recalc during seeks. Mixing happens
            // numerically here (computed color-mix strings are not parseable
            // across engines).
            function probeColor(cssColor, fallback) {
              var probe = root.ownerDocument.createElement("span");
              probe.style.color = cssColor;
              root.appendChild(probe);
              var out = getComputedStyle(probe).color || fallback;
              probe.remove();
              var m = out.match(/rgba?\(\s*([\d.]+)[,\s]+([\d.]+)[,\s]+([\d.]+)/);
              if (!m) {
                m = fallback.match(/rgba?\(\s*([\d.]+)[,\s]+([\d.]+)[,\s]+([\d.]+)/);
              }
              return m ? [Number(m[1]), Number(m[2]), Number(m[3])] : [113, 245, 167];
            }
            var accentRgb = probeColor(accentColors[accent], "rgb(113, 245, 167)");
            var fgRgb = probeColor("var(--fg, #f8fafc)", "rgb(248, 250, 252)");
            function mix(a, b, t) {
              return [
                Math.round(a[0] + (b[0] - a[0]) * t),
                Math.round(a[1] + (b[1] - a[1]) * t),
                Math.round(a[2] + (b[2] - a[2]) * t),
              ];
            }
            function rgba(c, a) {
              return "rgba(" + c[0] + "," + c[1] + "," + c[2] + "," + a + ")";
            }
            var bodyRgb = mix(accentRgb, fgRgb, 0.18);
            var softRgb = mix(accentRgb, fgRgb, 0.55);

            // The grain table: computed exactly once, then only read.
            var counts = { fine: 1500, coarse: 760 };
            var sizes = { fine: 0.0055, coarse: 0.0102 };
            var COUNT = counts[grain];
            var SPECK = sizes[grain] * minDim;
            var grains = (function () {
              var state = 0x50f7b10b;
              function next() {
                state = (Math.imul(1664525, state) + 1013904223) >>> 0;
                return state / 4294967296;
              }
              var rows = [];
              for (var i = 0; i < COUNT; i += 1) {
                // Radial distribution with a fuzzy tail past R: density thins
                // toward the boundary and alpha fades it out, so the edge is
                // granular vapor, never a line.
                var rr = Math.pow(next(), 0.55) * R * 1.16;
                var th = next() * Math.PI * 2;
                var edge = Math.max(0, Math.min(1, (1.16 - rr / R) / 0.42));
                rows.push({
                  x: Math.cos(th) * rr,
                  y: Math.sin(th) * rr * 0.94,
                  size: SPECK * (0.5 + 0.9 * next()),
                  dim: (0.3 + 0.7 * next()) * edge,
                  tone: next(),
                  driftAmp: (0.008 + 0.014 * next()) * minDim,
                  driftCycles: next() < 0.5 ? 1 : 2,
                  phaseX: next() * Math.PI * 2,
                  phaseY: next() * Math.PI * 2,
                });
              }
              return rows;
            })();

            function clamp01(v) {
              return v < 0 ? 0 : v > 1 ? 1 : v;
            }

            // Deformation params. Attack lifts both toward CUT value; the
            // recovery springs them home. The painter owns all amplitudes.
            var P = { bulge: 0, lean: 0 };
            var bCut = 1 - Math.pow(1 - CUT_FRAC, 2); // power2.out at the cut
            var vCut = (2 * (1 - CUT_FRAC)) / ATTACK_NAT; // slope there, per s
            var attackEase = function (p) {
              return (1 - Math.pow(1 - p * CUT_FRAC, 2)) / bCut;
            };
            // Closed-form underdamped spring x(s), x(0) = 1, x'(0) = vCut/bCut
            // (velocity preserved across the cut), corrected by a linear ramp
            // so x(RECOVER) is exactly zero. Higher frequency for the local
            // bulge, lower for the whole-mass lean: the surface snaps back
            // faster than the body.
            function springEase(lambda, omega) {
              var v0 = vCut / bCut;
              var c2 = (v0 + lambda) / omega;
              function x(s) {
                return Math.exp(-lambda * s) * (Math.cos(omega * s) + c2 * Math.sin(omega * s));
              }
              var xEnd = x(RECOVER);
              return function (p) {
                var s = p * RECOVER;
                return 1 - (x(s) - (s / RECOVER) * xEnd);
              };
            }
            var bulgeSpring = springEase(4.2, Math.PI * 2 * 2.2);
            var leanSpring = springEase(3.6, Math.PI * 2 * 1.5);

            // Pure repaint: clear, then rebuild the whole frame from
            // (grain table, P, t). Drift phase u completes integer sine
            // cycles over [0, IN_END] and is exactly zero from IN_END on,
            // so the HOLD frame is dead still.
            var sigma = R * 0.85;
            var bulgeAmp = R * 0.62;
            var leanAmp = minDim * 0.045;
            function paint(t) {
              ctx.clearRect(0, 0, W, H);
              var u = clamp01(t / IN_END);
              var lx = leanAmp * P.lean * dirX;
              var ly = leanAmp * P.lean * dirY;
              var cx = centerX + lx;
              var cy = centerY + ly;

              // Layered radial gradients: wide aura, mid glow, dense core,
              // and a bulge lobe that swells toward the touch point.
              var aura = ctx.createRadialGradient(cx, cy, 0, cx, cy, R * 1.9);
              aura.addColorStop(0, rgba(accentRgb, 0.16));
              aura.addColorStop(0.55, rgba(accentRgb, 0.06));
              aura.addColorStop(1, rgba(accentRgb, 0));
              ctx.fillStyle = aura;
              ctx.fillRect(0, 0, W, H);

              var mid = ctx.createRadialGradient(cx, cy, 0, cx, cy, R * 1.12);
              mid.addColorStop(0, rgba(bodyRgb, 0.34));
              mid.addColorStop(0.62, rgba(bodyRgb, 0.16));
              mid.addColorStop(1, rgba(bodyRgb, 0));
              ctx.fillStyle = mid;
              ctx.fillRect(0, 0, W, H);

              var core = ctx.createRadialGradient(
                cx - R * 0.12,
                cy - R * 0.14,
                0,
                cx,
                cy,
                R * 0.62,
              );
              core.addColorStop(0, rgba(softRgb, 0.4));
              core.addColorStop(1, rgba(softRgb, 0));
              ctx.fillStyle = core;
              ctx.fillRect(0, 0, W, H);

              if (P.bulge > 0.001) {
                var lobeX = cx + dirX * R * 0.72;
                var lobeY = cy + dirY * R * 0.72;
                var lobeR = R * (0.22 + 0.5 * P.bulge);
                var lobe = ctx.createRadialGradient(lobeX, lobeY, 0, lobeX, lobeY, lobeR);
                lobe.addColorStop(0, rgba(softRgb, 0.34 * P.bulge));
                lobe.addColorStop(1, rgba(softRgb, 0));
                ctx.fillStyle = lobe;
                ctx.fillRect(0, 0, W, H);
              }

              // Grain field. Each speck drifts on its own integer-cycle sine
              // (zero at u = 0 and u = 1) and is attracted toward the touch
              // point with an exponential falloff: the material near the dot
              // reaches for it, the far side barely stirs.
              var TAU = Math.PI * 2;
              for (var i = 0; i < grains.length; i += 1) {
                var g = grains[i];
                var driftX =
                  g.driftAmp * (Math.sin(TAU * g.driftCycles * u + g.phaseX) - Math.sin(g.phaseX));
                var driftY =
                  g.driftAmp * (Math.sin(TAU * g.driftCycles * u + g.phaseY) - Math.sin(g.phaseY));
                var gx = cx + g.x + driftX;
                var gy = cy + g.y + driftY;
                if (P.bulge > 0.001) {
                  var tx = touchX - gx;
                  var ty = touchY - gy;
                  var td = Math.hypot(tx, ty);
                  if (td > 0.5) {
                    var w = Math.exp(-td / sigma);
                    var pull = (bulgeAmp * P.bulge * w) / td;
                    gx += tx * pull;
                    gy += ty * pull;
                  }
                }
                var c = g.tone < 0.62 ? softRgb : fgRgb;
                ctx.globalAlpha = g.dim * 0.85;
                ctx.fillStyle = rgba(c, 1);
                ctx.beginPath();
                ctx.arc(gx, gy, g.size, 0, TAU);
                ctx.fill();
              }
              ctx.globalAlpha = 1;
            }

            // Touch dot choreography, transforms only, px space of the host
            // box (canvas coordinates divided by dpr).
            var stageW = cssW;
            var stageH = cssH;
            var dotX = touchX / dpr;
            var dotY = touchY / dpr;
            // Enter and leave along the attraction axis, from off stage.
            var away = Math.hypot(stageW, stageH) * 0.7;
            var offX = dotX + dirX * away;
            var offY = dotY + dirY * away;

            gsap.set(stage, { opacity: 1, y: "0cqh" });
            gsap.set(touchDot, { x: offX, y: offY, opacity: 0 });

            var tl = gsap.timeline({
              paused: true,
              onUpdate: function () {
                paint(tl.time());
              },
            });

            // Anchor tween: spans the full authored duration so seeks into
            // the hold keep tl.time() honest and onUpdate (the canvas
            // repaint) fires for every eventful seek anywhere in [0, D].
            tl.to({ p: 0 }, { p: 1, duration: duration, ease: "none" }, 0);

            // The dot decel-arrives (power3.out: it arrives, it never
            // passes through), dwells for the press, then accelerates away.
            var arriveStart = Math.max(0, touchAt - 0.85);
            tl.fromTo(
              touchDot,
              { x: offX, y: offY, opacity: 0 },
              {
                x: dotX,
                y: dotY,
                opacity: 1,
                duration: touchAt - arriveStart,
                ease: "power3.out",
              },
              arriveStart,
            );
            tl.fromTo(
              touchDot,
              { x: dotX, y: dotY, opacity: 1 },
              {
                x: offX,
                y: offY,
                opacity: 0,
                duration: 0.55,
                ease: "power2.in",
                immediateRender: false,
              },
              cutAt,
            );

            // Attack: the truncated lean-in, cut mid-flight at the dot lift.
            tl.fromTo(
              P,
              { bulge: 0, lean: 0 },
              { bulge: bCut, lean: bCut, duration: ATTACK, ease: attackEase },
              touchAt,
            );
            // Recovery: velocity-matched closed-form springs back to rest.
            tl.fromTo(
              P,
              { bulge: bCut },
              {
                bulge: 0,
                duration: RECOVER,
                ease: bulgeSpring,
                immediateRender: false,
              },
              cutAt,
            );
            tl.fromTo(
              P,
              { lean: bCut },
              {
                lean: 0,
                duration: RECOVER,
                ease: leanSpring,
                immediateRender: false,
              },
              cutAt,
            );

            // HOLD: truly still. Drift is zero past IN_END by construction
            // and both params are home, so every hold frame is identical.

            // OUT: optional departure; exit none holds until the frame cuts.
            if (exit === "up") {
              tl.to(stage, { y: "-4cqh", duration: OUT, ease: "power2.in" }, OUT_START);
              tl.to(stage, { opacity: 0, 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);
            paint(0);
            window.__timelines = window.__timelines || {};
            window.__timelines["soft-blob-touch"] = tl;
          })();
        </script>
      </div>
    </template>
  </body>
</html>
```

Copy npx hyperframes add soft-blob-touch to the clipboard

That writes one file: `compositions/components/soft-blob-touch.html`.

## Paste it into your composition

Open `compositions/components/soft-blob-touch.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 |
| - | - | - | - |
| `touch_x` | `66` | 8% to 92%, step 1% | Touch point, percent of host width. |
| `touch_y` | `38` | 8% to 92%, step 1% | Touch point, percent of host height. |
| `touch_at` | `1.6` | 0.9s to 10s, step 0.1s | Seconds from mount start when the dot makes contact. |
| `grain` | `fine` | `fine`, `coarse` | Speck register for the granular body. |
| `accent` | `green` | `green`, `blue`, `violet` | Body tint: green rides --brand, blue rides --accent, violet rides --accent-2. |
| `exit` | `none` | `none`, `fade`, `up` | Optional departure. Default none: the settled blob holds until the frame cuts. |

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="soft-blob-touch"
  data-composition-src="compositions/components/soft-blob-touch.html"
  data-variable-values='{"touch_x":66,"touch_y":38,"touch_at":1.6,"grain":"fine","accent":"green","exit":"none"}'
></div>
```

Tagged `motion-primitive` `product-demo` `material` `blob` `touch` `grain`.

## Related topics

* [Browse the complete Catalog](/catalog.md)
* [Add assets and Catalog items in the browser editor](/studio/assets-and-blocks.md)
* [Put blocks together into one video](/concepts/compositions.md)


## Related topics

- [Blob](/catalog/blocks/blob.md)
- [Minimal Gradient Background](/catalog/blocks/mk-background.md)
- [Soft Blur In](/catalog/components/soft-blur-in.md)


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