@thi.ng/ramp/easing.js

Extensible keyframe interpolation/tweening of arbitrary, nested types

import { easeInOut5 } from "@thi.ng/math/easing";
import { norm } from "@thi.ng/math/fit";
import { mix } from "@thi.ng/math/mix";
import { Ramp } from "./ramp.js";
const easing = (stops, opts) => new Ramp(EASING_N(opts?.easing), stops, opts);
const EASING_N = (easing2 = easeInOut5) => {
  return {
    min: (acc, x) => Math.min(acc ?? Infinity, x),
    max: (acc, x) => Math.max(acc ?? -Infinity, x),
    at: (stops, i, t) => {
      const a = stops[i];
      const b = stops[i + 1];
      return mix(a[1], b[1], easing2(norm(t, a[0], b[0])));
    }
  };
};
const EASING_V = (vec, easing2 = easeInOut5) => ({
  min: (acc, x) => vec.min(acc, acc || vec.vecOf(Infinity), x),
  max: (acc, x) => vec.max(acc, acc || vec.vecOf(-Infinity), x),
  at: (stops, i, t) => {
    const a = stops[i];
    const b = stops[i + 1];
    return vec.mixN([], a[1], b[1], easing2(norm(t, a[0], b[0])));
  }
});
export {
  EASING_N,
  EASING_V,
  easing
};