darker method

Color darker(
  1. int percents
)

Make color darker by so many percents

Implementation

Color darker(int percents) {
  assert(percents >= 1 && percents <= 100);
  final int rgbPercent = (percents / 100 * 255).round();
  int red = this.red - rgbPercent,
      green = this.green - rgbPercent,
      blue = this.blue - rgbPercent;
  if (red < 0) {
    red = 0;
  }
  if (green < 0) {
    green = 0;
  }
  if (blue < 0) {
    blue = 0;
  }
  return Color.fromARGB(alpha, red, green, blue);
}