@blinn-motion/core is time-based (seconds) and DOM-free. The whole engine hangs off a single deterministic function; every adapter is a thin painter on top of it.

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sample(doc, t)

sample walks the document, samples every track at time t, composes stacked tracks per property over the base value, and returns a resolved render tree — every transform, RGBA color and shape vertex is a final number. 
import { sample } from "@blinn-motion/core";

const tree = sample(doc, 0.8); // resolve the whole doc at t = 0.8s
// tree is a backend-agnostic RenderNode[] — no DOM, no canvas, just numbers
Because it’s pure, the same t always yields the same tree. That determinism is what makes an animation time identically on the DOM, on a canvas, and on native views.
1

Walk

Recurse the layer tree. Children resolve relative to their parent’s animated box.
2

Sample

For each track, find the active keyframe segment at t, ease the local progress, and interpolate the value.
3

Compose

Combine each track’s value with the base via its op (set / offset / scale). Stacked tracks apply in order.
4

Resolve

Emit a RenderNode with final transforms, colors, vertices and effects.

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Composition

A property can be driven by several tracks. They fold over the base value left to right: 
// base = 0, then two tracks on translateY:
// track A (offset): +80 → 0   (spring entrance)
// track B (offset): hover nudge -6
// resolved = base + A + B
  • set replaces the running value.
  • offset adds to it.
  • scale multiplies it.
This is why springs, curves and interaction offsets layer without fighting each other.

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The shared clock: Ticker

Adapters don’t run their own timers. They build a Ticker — the shared playback clock — and call sample on each frame. The Ticker owns time, loop, rate (speed) and the onframe callback, so play / pause / seek / seekFraction behave the same everywhere. 
import { Ticker, sample } from "@blinn-motion/core";

const ticker = new Ticker({
  duration: doc.duration,
  loop: true,
  onframe: (t, fraction) => paint(sample(doc, t)),
});

ticker.play();

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What the core exports

sample is the headline, but the core is a toolkit of pure helpers — easing solvers, color interpolation, shape vertex math, paint resolution. See the core API reference for the full surface.

Core API reference

sample, computeLayer, Ticker, and the easing / color / shape / paint helpers.