@thi.ng/color/cosine-gradients.js

Array-based color types, CSS parsing, conversions, transformations, declarative theme generation, gradients, presets

import { partial } from "@thi.ng/compose/partial";
import { TAU } from "@thi.ng/math/api";
import { clamp01 } from "@thi.ng/math/interval";
import { comp } from "@thi.ng/transducers/comp";
import { map } from "@thi.ng/transducers/map";
import { noop } from "@thi.ng/transducers/noop";
import { normRange } from "@thi.ng/transducers/norm-range";
import { push } from "@thi.ng/transducers/push";
import { transduce } from "@thi.ng/transducers/transduce";
import { tween } from "@thi.ng/transducers/tween";
import { zip } from "@thi.ng/transducers/zip";
import { setS4 } from "@thi.ng/vectors/sets";
import { clamp } from "./clamp.js";
const COSINE_GRADIENTS = {
  "blue-cyan": [
    [0, 0.5, 0.5, 1],
    [0, 0.5, 0.5, 0],
    [0, 0.5, 0.3333, 0],
    [0, 0.5, 0.6666, 0]
  ],
  "blue-magenta-orange": [
    [0.938, 0.328, 0.718, 1],
    [0.659, 0.438, 0.328, 0],
    [0.388, 0.388, 0.296, 0],
    [2.538, 2.478, 0.168, 0]
  ],
  "blue-white-red": [
    [0.66, 0.56, 0.68, 1],
    [0.718, 0.438, 0.72, 0],
    [0.52, 0.8, 0.52, 0],
    [-0.43, -0.397, -0.083, 0]
  ],
  "cyan-magenta": [
    [0.61, 0.498, 0.65, 1],
    [0.388, 0.498, 0.35, 0],
    [0.53, 0.498, 0.62, 0],
    [3.438, 3.012, 4.025, 0]
  ],
  "green-blue-orange": [
    [0.892, 0.725, 0, 1],
    [0.878, 0.278, 0.725, 0],
    [0.332, 0.518, 0.545, 0],
    [2.44, 5.043, 0.732, 0]
  ],
  "green-cyan": [
    [0, 0.5, 0.5, 1],
    [0, 0.5, 0.5, 0],
    [0, 0.3333, 0.5, 0],
    [0, 0.6666, 0.5, 0]
  ],
  "green-magenta": [
    [0.6666, 0.5, 0.5, 1],
    [0.5, 0.6666, 0.5, 0],
    [0.6666, 0.666, 0.5, 0],
    [0.2, 0, 0.5, 0]
  ],
  "green-red": [
    [0.5, 0.5, 0, 1],
    [0.5, 0.5, 0, 0],
    [0.5, 0.5, 0, 0],
    [0.5, 0, 0, 0]
  ],
  heat1: [
    [0.5, 0.4, 0.25, 1],
    [0.5, 0.5, 0.666, 0],
    [0.5, 0.666, 0.8, 0],
    [0.5, 0.666, 0.8, 0]
  ],
  "magenta-green": [
    [0.59, 0.811, 0.12, 1],
    [0.41, 0.392, 0.59, 0],
    [0.94, 0.548, 0.278, 0],
    [-4.242, -6.611, -4.045, 0]
  ],
  "orange-blue": [
    [0.5, 0.5, 0.5, 1],
    [0.5, 0.5, 0.5, 0],
    [0.8, 0.8, 0.5, 0],
    [0, 0.2, 0.5, 0]
  ],
  "orange-magenta-blue": [
    [0.821, 0.328, 0.242, 1],
    [0.659, 0.481, 0.896, 0],
    [0.612, 0.34, 0.296, 0],
    [2.82, 3.026, -0.273, 0]
  ],
  "purple-orange-cyan": [
    [0.5, 0.5, 0.5, 1],
    [0.5, 0.5, 0.5, 0],
    [0.5, 0.5, 1, 0],
    [-0.25, 0.5, 1, 0]
  ],
  rainbow1: [
    [0.5, 0.5, 0.5, 1],
    [0.5, 0.5, 0.5, 0],
    [1, 1, 1, 0],
    [0, 0.3333, 0.6666, 0]
  ],
  rainbow2: [
    [0.5, 0.5, 0.5, 1],
    [0.666, 0.666, 0.666, 0],
    [1, 1, 1, 0],
    [0, 0.3333, 0.6666, 0]
  ],
  rainbow3: [
    [0.5, 0.5, 0.5, 1],
    [0.75, 0.75, 0.75, 0],
    [1, 1, 1, 0],
    [0, 0.3333, 0.6666, 0]
  ],
  rainbow4: [
    [0.5, 0.5, 0.5, 1],
    [1, 1, 1, 0],
    [1, 1, 1, 0],
    [0, 0.3333, 0.6666, 0]
  ],
  "red-blue": [
    [0.5, 0, 0.5, 1],
    [0.5, 0, 0.5, 0],
    [0.5, 0, 0.5, 0],
    [0, 0, 0.5, 0]
  ],
  "yellow-green-blue": [
    [0.65, 0.5, 0.31, 1],
    [-0.65, 0.5, 0.6, 0],
    [0.333, 0.278, 0.278, 0],
    [0.66, 0, 0.667, 0]
  ],
  "yellow-magenta-cyan": [
    [1, 0.5, 0.5, 1],
    [0.5, 0.5, 0.5, 0],
    [0.75, 1, 0.6666, 0],
    [0.8, 1, 0.3333, 0]
  ],
  "yellow-purple-magenta": [
    [0.731, 1.098, 0.192, 1],
    [0.358, 1.09, 0.657, 0],
    [1.077, 0.36, 0.328, 0],
    [0.965, 2.265, 0.837, 0]
  ],
  "yellow-red": [
    [0.5, 0.5, 0, 1],
    [0.5, 0.5, 0, 0],
    [0.1, 0.5, 0, 0],
    [0, 0, 0, 0]
  ]
};
const cosineColor = (spec, t) => transduce(
  map(
    ([a, b, c, d]) => clamp01(a + b * Math.cos(TAU * (c * t + d)))
  ),
  push(),
  // @ts-ignore
  zip(...spec)
);
const cosineGradient = (n, spec, tx) => transduce(
  comp(map(partial(cosineColor, spec)), tx ? map(tx) : noop()),
  push(),
  normRange(n - 1)
);
const cosineGradientBuffer = (n, spec, buffer = [], offset = 0, cstride = 1, estride = 4) => {
  for (const t of normRange(n - 1)) {
    setS4(buffer, cosineColor(spec, t), offset, 0, cstride);
    offset += estride;
  }
  return buffer;
};
const cosineCoeffs = (from, to) => {
  from = clamp([], from);
  to = clamp([], to);
  const amp = [...map(([a, b]) => 0.5 * (a - b), zip(from, to))];
  return [
    [...map(([s, a]) => s - a, zip(from, amp))],
    amp,
    [-0.5, -0.5, -0.5, -0.5],
    [0, 0, 0, 0]
  ];
};
const multiCosineGradient = (opts) => transduce(
  opts.tx ? map(opts.tx) : noop(),
  push(),
  tween({
    num: opts.num,
    stops: opts.stops,
    easing: opts.easing,
    min: 0,
    max: 1,
    init: cosineCoeffs,
    mix: cosineColor
  })
);
export {
  COSINE_GRADIENTS,
  cosineCoeffs,
  cosineColor,
  cosineGradient,
  cosineGradientBuffer,
  multiCosineGradient
};