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#include <private/qdrawhelper_p.h>

QT_BEGIN_NAMESPACE


QDrawHelperGammaTables::QDrawHelperGammaTables(qreal smoothing)
{
    const qreal gray_gamma = 2.31;
    for (int i=0; i<256; ++i)
        qt_pow_gamma[i] = uint(qRound(qPow(i / qreal(255.), gray_gamma) * 2047));
    for (int i=0; i<2048; ++i)
        qt_pow_invgamma[i] = uchar(qRound(qPow(i / qreal(2047.0), 1 / gray_gamma) * 255));

    refresh(smoothing);
}

void QDrawHelperGammaTables::refresh(qreal smoothing)
{
    for (int i=0; i<256; ++i) {
        qt_pow_rgb_gamma[i] = uchar(qRound(qPow(i / qreal(255.0), smoothing) * 255));
        qt_pow_rgb_invgamma[i] = uchar(qRound(qPow(i / qreal(255.), 1 / smoothing) * 255));
    }
}

QT_END_NAMESPACE