public static HslColor FromColor(Color color)
{
double r = color.R / 255.0;
double g = color.G / 255.0;
double b = color.B / 255.0;
var hsl = new HslColor {A = color.A / 255.0};
double v = Math.Max(r, g);
v = Math.Max(v, b);
double m = Math.Min(r, g);
m = Math.Min(m,b);
hsl.L = (m + v) / 2.0;
if (hsl.L <= 0.0)
return hsl;
double vm = v - m;
hsl.S = vm;
if (hsl.S > 0.0)
hsl.S /= (hsl.L <= 0.5) ? (v + m ) : (2.0 - v - m);
else
return hsl;
double r2 = (v - r) / vm;
double g2 = (v - g) / vm;
double b2 = (v - b) / vm;
if (Math.Abs(r - v) < double.Epsilon)
{
hsl.H = (Math.Abs(g - m) < double.Epsilon ? 5.0 + b2 : 1.0 - g2);
}
else if (Math.Abs(g - v) < double.Epsilon)
{
hsl.H = (Math.Abs(b - m) < double.Epsilon ? 1.0 + r2 : 3.0 - b2);
}
else
{
hsl.H = (Math.Abs(r - m) < double.Epsilon ? 3.0 + g2 : 5.0 - r2);
}
hsl.H /= 6.0;
return hsl;
}
