hslToHex function

String hslToHex(HSL color)

Implementation

String hslToHex(HSL color) {
  final h = color.h / 360;
  final s = color.s / 100;
  final l = color.l / 100;
  var r, g, b;
  if (s == 0) {
    r = g = b = l; // achromatic
  } else {
    Function hue2rgb = (double p, double q, double t) {
      if (t < 0) t += 1;
      if (t > 1) t -= 1;
      if (t < 1 / 6) return p + (q - p) * 6 * t;
      if (t < 1 / 2) return q;
      if (t < 2 / 3) return p + (q - p) * (2 / 3 - t) * 6;
      return p;
    };
    var q = l < 0.5 ? l * (1 + s) : l + s - l * s;
    var p = 2 * l - q;
    r = hue2rgb(p, q, h + 1 / 3);
    g = hue2rgb(p, q, h);
    b = hue2rgb(p, q, h - 1 / 3);
  }
  Function toHex = (double x) {
    var hex = (x * 255).round().toRadixString(16);
    return hex.length == 1 ? '0' + hex : hex;
  };
  return "#" + toHex(r) + toHex(g) + toHex(b);
}