public static Color ShiftLightness(this Color color, int amount = 1)
{
var lab = color.ToLab();
var shifted = new Lab(lab.L - LabConstants.Kn * amount, lab.A, lab.B);
return(shifted.ToColor());
}
public static Xyz ToXyz(this Lab lab)
{
double LabXyz(double d)
{
if (d > LabConstants.ECubedRoot)
{
return(d * d * d);
}
return((116 * d - 16) / LabConstants.K);
}
var y = (lab.L + 16.0) / 116.0;
var x = double.IsNaN(lab.A) ? y : y + lab.A / 500.0;
var z = double.IsNaN(lab.B) ? y : y - lab.B / 200.0;
y = LabConstants.WhitePointY * LabXyz(y);
x = LabConstants.WhitePointX * LabXyz(x);
z = LabConstants.WhitePointZ * LabXyz(z);
return(new Xyz(x, y, z));
}
public static Color ToColor(this Lab lab)
{
var xyz = lab.ToXyz();
return(xyz.ToColor());
}
