static void XYZ_to_sRGB_WhitePoint(FX_FLOAT X,
FX_FLOAT Y,
FX_FLOAT Z,
FX_FLOAT& R,
FX_FLOAT& G,
FX_FLOAT& B,
FX_FLOAT Xw,
FX_FLOAT Yw,
FX_FLOAT Zw) {
// The following RGB_xyz is based on
// sRGB value {Rx,Ry}={0.64, 0.33}, {Gx,Gy}={0.30, 0.60}, {Bx,By}={0.15, 0.06}
FX_FLOAT Rx = 0.64f, Ry = 0.33f;
FX_FLOAT Gx = 0.30f, Gy = 0.60f;
FX_FLOAT Bx = 0.15f, By = 0.06f;
CFX_Matrix_3by3 RGB_xyz(Rx, Gx, Bx, Ry, Gy, By, 1 - Rx - Ry, 1 - Gx - Gy,
1 - Bx - By);
CFX_Vector_3by1 whitePoint(Xw, Yw, Zw);
CFX_Vector_3by1 XYZ(X, Y, Z);
CFX_Vector_3by1 RGB_Sum_XYZ = RGB_xyz.Inverse().TransformVector(whitePoint);
CFX_Matrix_3by3 RGB_SUM_XYZ_DIAG(RGB_Sum_XYZ.a, 0, 0, 0, RGB_Sum_XYZ.b, 0, 0,
0, RGB_Sum_XYZ.c);
CFX_Matrix_3by3 M = RGB_xyz.Multiply(RGB_SUM_XYZ_DIAG);
CFX_Vector_3by1 RGB = M.Inverse().TransformVector(XYZ);
R = RGB_Conversion(RGB.a);
G = RGB_Conversion(RGB.b);
B = RGB_Conversion(RGB.c);
}
static void XYZ_to_sRGB(FX_FLOAT X, FX_FLOAT Y, FX_FLOAT Z, FX_FLOAT& R, FX_FLOAT& G, FX_FLOAT& B)
{
FX_FLOAT R1 = 3.2410f * X - 1.5374f * Y - 0.4986f * Z;
FX_FLOAT G1 = -0.9692f * X + 1.8760f * Y + 0.0416f * Z;
FX_FLOAT B1 = 0.0556f * X - 0.2040f * Y + 1.0570f * Z;
R = RGB_Conversion(R1);
G = RGB_Conversion(G1);
B = RGB_Conversion(B1);
}
