vahidk/colorTransform.js

type HslType = { h: number; s: number; l: number }
const hslToRgb = (hsl: HslType): RgbType => {
  let { h, s, l } = hsl
  // IMPORTANT if s and l between 0,1 remove the next two lines:
  s /= 100
  l /= 100
  const k = (n: number) => (n + h / 30) % 12
  const a = s * Math.min(l, 1 - l)
  const f = (n: number) =>
    l - a * Math.max(-1, Math.min(k(n) - 3, Math.min(9 - k(n), 1)))
  return {
    r: Math.round(255 * f(0)),
    g: Math.round(255 * f(8)),
    b: Math.round(255 * f(4)),
  }
}