relativeLuminance function
Returns WCAG-style relative luminance for a color.
The result is normalized between 0.0 (black) and 1.0 (white).
Implementation
double relativeLuminance(Color color, {bool hasDarkBackground = true}) {
final rgb = _toRgb(color, hasDarkBackground: hasDarkBackground);
if (rgb == null) {
throw ArgumentError('Unable to resolve color to RGB for contrast math');
}
return _relativeLuminanceFromRgb(rgb.r, rgb.g, rgb.b);
}