float-hsl2rgb/index.js

converts [H,S,L] to [R,G,B]

module.exports = hsl2rgb
function hsl2rgb (hsl) {
  var h = hsl[0],
    s = hsl[1],
    l = hsl[2],
    t1, t2, t3, rgb, val

  if (s === 0) {
    val = l
    return [val, val, val]
  }

  if (l < 0.5) {
    t2 = l * (1 + s)
  } else {
    t2 = l + s - l * s
  }
  t1 = 2 * l - t2

  rgb = [0, 0, 0]
  for (var i = 0; i < 3; i++) {
    t3 = h + 1 / 3 * -(i - 1)
    if (t3 < 0) {
      t3++
    }
    if (t3 > 1) {
      t3--
    }

    if (6 * t3 < 1) {
      val = t1 + (t2 - t1) * 6 * t3
    } else if (2 * t3 < 1) {
      val = t2
    } else if (3 * t3 < 2) {
      val = t1 + (t2 - t1) * (2 / 3 - t3) * 6
    } else {
      val = t1
    }

    rgb[i] = val
  }

  return rgb
}