thi-ng/umbrella

import type { NumericArray } from "@thi.ng/api";
import type { IRandom } from "@thi.ng/random";
import type { Color, ColorFactory, ReadonlyColor, TypedColor } from "../api.js";
import { defColor } from "../defcolor.js";
import { lchLab } from "../lab/lab-lch.js";
import { labXyz, labXyzD65 } from "../lab/lab-xyz.js";
import { rgbOklab } from "../rgb/rgb-oklab.js";
import { xyzOklab } from "../xyz/xyz-oklab.js";
import { xyzXyzD50_65 } from "../xyz/xyz-xyz.js";
import { oklabRgb } from "./oklab-rgb.js";

export declare class Oklab implements TypedColor<Oklab> {
    buf: NumericArray;
    offset: number;
    stride: number;
    l: number;
    a: number;
    b: number;
    alpha: number;
    [id: number]: number;
    readonly mode: "oklab";
    readonly length: 4;
    readonly range: [ReadonlyColor, ReadonlyColor];
    readonly xyz: [number, number, number];
    [Symbol.iterator](): Iterator<number, any, undefined>;
    clamp(): this;
    copy(): Oklab;
    copyView(): Oklab;
    deref(): Color;
    empty(): Oklab;
    eqDelta(o: Oklab, eps?: number): boolean;
    randomize(rnd?: IRandom): this;
    set(src: ReadonlyColor): this;
    toJSON(): number[];
}

/**
 * Oklab color type. Conversions assume {@link D65} white point).
 *
 * @remarks
 * Reference: https://bottosson.github.io/posts/oklab/
 */
export const oklab = <ColorFactory<Oklab>>defColor({
    mode: "oklab",
    channels: {
        a: { range: [-0.2339, 0.2762] },
        b: { range: [-0.3115, 0.1986] },
    },
    order: <const>["l", "a", "b", "alpha"],
    from: {
        lab50: [labXyz, xyzXyzD50_65, xyzOklab],
        lab65: [labXyzD65, xyzOklab],
        lch: [lchLab, labXyzD65, xyzOklab],
        rgb: rgbOklab,
        xyz50: [xyzXyzD50_65, xyzOklab],
        xyz65: xyzOklab,
    },
    toRgb: oklabRgb,
});