Method tint

libraries/rainbow/src/rainbow.cpp:291–326

}

QColor Rainbow::tint(const QColor &base, const QColor &color, qreal amount)
{
    if (amount <= 0.0)
    {
        return base;
    }
    if (amount >= 1.0)
    {
        return color;
    }
    if (qIsNaN(amount))
    {
        return base;
    }

    qreal baseLuma = luma(base); // cache value because luma call is expensive
    double ri = contrastRatioForLuma(baseLuma, luma(color));
    double rg = 1.0 + ((ri + 1.0) * amount * amount * amount);
    double u = 1.0, l = 0.0;
    QColor result;
    for (int i = 12; i; --i)
    {
        double a = 0.5 * (l + u);
        result = tintHelper(base, baseLuma, color, a);
        double ra = contrastRatioForLuma(baseLuma, luma(result));
        if (ra > rg)
        {
            u = a;
        }
        else
        {
            l = a;
        }
    }
    return result;
}

QColor Rainbow::mix(const QColor &c1, const QColor &c2, qreal bias)
{