brightness property
double
get
brightness
Gets the brightness of this color (0.0 to 1.0)
Implementation
double get brightness {
return (((r * 255.0).round() & 0xff) * 0.299 +
((g * 255.0).round() & 0xff) * 0.587 +
((b * 255.0).round() & 0xff) * 0.114) /
255.0;
}