Function hslToRGB

src/utils/color.ts:59–78

({h, s, l, a = 1}: HSLA)

// https://en.wikipedia.org/wiki/HSL_and_HSV
export function hslToRGB({h, s, l, a = 1}: HSLA): RGBA {
    if (s === 0) {
        const [r, b, g] = [l, l, l].map((x) => Math.round(x * 255));
        return {r, g, b, a};
    }

    const c = (1 - Math.abs(2 * l - 1)) * s;
    const x = c * (1 - Math.abs((h / 60) % 2 - 1));
    const m = l - c / 2;
    const [r, g, b] = (
        h < 60 ? [c, x, 0] :
            h < 120 ? [x, c, 0] :
                h < 180 ? [0, c, x] :
                    h < 240 ? [0, x, c] :
                        h < 300 ? [x, 0, c] :
                            [c, 0, x]
    ).map((n) => Math.round((n + m) * 255));

    return {r, g, b, a};
}

// https://en.wikipedia.org/wiki/HSL_and_HSV
export function rgbToHSL({r: r255, g: g255, b: b255, a = 1}: RGBA): HSLA {