public static C3f FromXYZToYxy(this C3f XYZ)
{
double Y = XYZ.G;
double x = XYZ.R / (XYZ.R + XYZ.G + XYZ.B);
double y = XYZ.G / (XYZ.R + XYZ.G + XYZ.B);
return(new C3f(Y, x, y));
}
public static C3f FromYuvToYxy(this C3f Yuv)
{
var Y = Yuv.R;
var u = Yuv.G;
var v = Yuv.B;
return(new C3f(Y,
3 * u / (2 * u - 8 * v + 4),
2 * v / (2 * u - 8 * v + 4)));
}
public static C4f GetLodColor(int level, int maxLevel)
{
if (maxLevel == 0)
{
return(C4f.Red);
}
float hue = ((float)level / (float)maxLevel) * 2 / (float)3;
return(C3f.FromHSV(hue, 1.0f, 1.0f).ToC4f());
}
/// <summary>
/// converts Lab-color to XYZ-color
/// </summary>
/// <param name="lab">L=[0,100], a=[-150,150], b=[-150,150]</param>
/// <returns></returns>
public static C3f LabToXYZ(this C3f lab)
{
var L = lab.R;
var a = lab.G;
var b = lab.B;
var d = (1.0f / 116.0f) * (L + 16);
var Y = YREF * fInv(d);
var X = XREF * fInv(d + a / 500.0f);
var Z = ZREF * fInv(d - b / 200.0f);
return(new C3f(X, Y, Z));
}
public static C3f FromYxyToXYZ(this C3f Yxy)
{
double Y = Yxy.R;
double x = Yxy.G;
double y = Yxy.B;
//AZ: check for y == 0 needed - szabo: DONE
if (y == 0)
{
y = double.Epsilon;
}
return(new C3f((x * (Y / y)), Y, ((1 - x - y) * (Y / y))));
}
/// <summary>
/// Converts XYZ-color to Lab-color
/// </summary>
/// <param name="xyz"></param>
/// <returns></returns>
public static C3f XYZToLab(this C3f xyz)
{
var X = xyz.R / XREF;
var Y = xyz.G / YREF;
var Z = xyz.B / ZREF;
var fx = f(X);
var fy = f(Y);
var fz = f(Z);
var L = (116 * fy) - 16;
var a = 500 * (fx - fy);
var b = 200 * (fy - fz);
return(new C3f(L, a, b));
}
/// <summary>
/// Returns the int representation of the supplied C3f color.
/// </summary>
public static int FromRgbToInt(this C3f self)
{
return(Col.ByteFromDouble(self.R) << 16 |
Col.ByteFromDouble(self.G) << 8 |
Col.ByteFromDouble(self.B));
}
/// <summary>
/// Returns the GamutMap represantion of the supplied C3f.
/// </summary>
public static C3f ToGamutMap(this C3f self)
{
return(self.Clamped(0.0f, 1.0f));
}
public void Write(C3f c)
{
Write(c.R); Write(c.G); Write(c.B);
}
public void Write(C3f value)
{
base.Write(Conversion.HostToNetworkOrder(value.R));
base.Write(Conversion.HostToNetworkOrder(value.G));
base.Write(Conversion.HostToNetworkOrder(value.B));
}
/// <summary>Computes MD5 hash of given data.</summary>
public static Guid ComputeMd5Hash(this C3f x)
=> ComputeMd5Hash(bw => { bw.Write(x.R); bw.Write(x.G); bw.Write(x.B); });
/// <summary>
/// C3f to System.Drawing.Color.
/// </summary>
public static Color ToColor(this C3f color) => Color.FromArgb(
Col.ByteFromFloatClamped(color.R),
Col.ByteFromFloatClamped(color.G),
Col.ByteFromFloatClamped(color.B));
