void
cvtcolor( /* convert a CIE XYZ color to RGB */
COLOR radrgb,
register C_COLOR *ciec,
double intensity
)
{
static COLOR ciexyz;
c_ccvt(ciec, C_CSXY); /* get xy representation */
ciexyz[1] = intensity;
ciexyz[0] = ciec->cx/ciec->cy*ciexyz[1];
ciexyz[2] = ciexyz[1]*(1./ciec->cy - 1.) - ciexyz[0];
cie_rgb(radrgb, ciexyz);
}
void
ccy2rgb( /* convert MGF color to RGB */
C_COLOR *cin, /* input MGF chrominance */
double cieY, /* input luminance or reflectance */
COLOR cout /* output RGB color */
)
{
double d;
COLOR xyz;
/* get CIE XYZ representation */
c_ccvt(cin, C_CSXY);
d = cin->cx/cin->cy;
xyz[CIEX] = d * cieY;
xyz[CIEY] = cieY;
xyz[CIEZ] = (1./cin->cy - d - 1.) * cieY;
cie_rgb(cout, xyz);
}
