diff options
Diffstat (limited to 'src/gui/painting/qcolorspace.cpp')
| -rw-r--r-- | src/gui/painting/qcolorspace.cpp | 159 |
1 files changed, 135 insertions, 24 deletions
diff --git a/src/gui/painting/qcolorspace.cpp b/src/gui/painting/qcolorspace.cpp index 24785f7b61..8d3bbbe412 100644 --- a/src/gui/painting/qcolorspace.cpp +++ b/src/gui/painting/qcolorspace.cpp @@ -53,6 +53,104 @@ QT_BEGIN_NAMESPACE +QBasicMutex QColorSpacePrivate::s_lutWriteLock; + +QColorSpacePrimaries::QColorSpacePrimaries(QColorSpace::Gamut gamut) +{ + switch (gamut) { + case QColorSpace::Gamut::SRgb: + redPoint = QPointF(0.640, 0.330); + greenPoint = QPointF(0.300, 0.600); + bluePoint = QPointF(0.150, 0.060); + whitePoint = QColorVector::D65Chromaticity(); + break; + case QColorSpace::Gamut::DciP3D65: + redPoint = QPointF(0.680, 0.320); + greenPoint = QPointF(0.265, 0.690); + bluePoint = QPointF(0.150, 0.060); + whitePoint = QColorVector::D65Chromaticity(); + break; + case QColorSpace::Gamut::Bt2020: + redPoint = QPointF(0.708, 0.292); + greenPoint = QPointF(0.190, 0.797); + bluePoint = QPointF(0.131, 0.046); + whitePoint = QColorVector::D65Chromaticity(); + break; + case QColorSpace::Gamut::AdobeRgb: + redPoint = QPointF(0.640, 0.330); + greenPoint = QPointF(0.210, 0.710); + bluePoint = QPointF(0.150, 0.060); + whitePoint = QColorVector::D65Chromaticity(); + break; + case QColorSpace::Gamut::ProPhotoRgb: + redPoint = QPointF(0.7347, 0.2653); + greenPoint = QPointF(0.1596, 0.8404); + bluePoint = QPointF(0.0366, 0.0001); + whitePoint = QColorVector::D50Chromaticity(); + break; + default: + Q_UNREACHABLE(); + } +} + +bool QColorSpacePrimaries::areValid() const +{ + if (!QColorVector::isValidChromaticity(redPoint)) + return false; + if (!QColorVector::isValidChromaticity(greenPoint)) + return false; + if (!QColorVector::isValidChromaticity(bluePoint)) + return false; + if (!QColorVector::isValidChromaticity(whitePoint)) + return false; + return true; +} + +QColorMatrix QColorSpacePrimaries::toXyzMatrix() const +{ + // This converts to XYZ in some undefined scale. + QColorMatrix toXyz = { QColorVector(redPoint), + QColorVector(greenPoint), + QColorVector(bluePoint) }; + + // Since the white point should be (1.0, 1.0, 1.0) in the + // input, we can figure out the scale by using the + // inverse conversion on the white point. + QColorVector wXyz(whitePoint); + QColorVector whiteScale = toXyz.inverted().map(wXyz); + + // Now we have scaled conversion to XYZ relative to the given whitepoint + toXyz = toXyz * QColorMatrix::fromScale(whiteScale); + + // But we want a conversion to XYZ relative to D50 + QColorVector wXyzD50 = QColorVector::D50(); + + if (wXyz != wXyzD50) { + // Do chromatic adaptation to map our white point to XYZ D50. + + // The Bradford method chromatic adaptation matrix: + QColorMatrix abrad = { { 0.8951f, -0.7502f, 0.0389f }, + { 0.2664f, 1.7135f, -0.0685f }, + { -0.1614f, 0.0367f, 1.0296f } }; + QColorMatrix abradinv = { { 0.9869929f, 0.4323053f, -0.0085287f }, + { -0.1470543f, 0.5183603f, 0.0400428f }, + { 0.1599627f, 0.0492912f, 0.9684867f } }; + + QColorVector srcCone = abrad.map(wXyz); + QColorVector dstCone = abrad.map(wXyzD50); + + QColorMatrix wToD50 = { { dstCone.x / srcCone.x, 0, 0 }, + { 0, dstCone.y / srcCone.y, 0 }, + { 0, 0, dstCone.z / srcCone.z } }; + + + QColorMatrix chromaticAdaptation = abradinv * (wToD50 * abrad); + toXyz = chromaticAdaptation * toXyz; + } + + return toXyz; +} + QColorSpacePrivate::QColorSpacePrivate() : id(QColorSpace::Unknown) , gamut(QColorSpace::Gamut::Custom) @@ -128,6 +226,21 @@ QColorSpacePrivate::QColorSpacePrivate(QColorSpace::Gamut gamut, QColorSpace::Tr initialize(); } +QColorSpacePrivate::QColorSpacePrivate(const QColorSpacePrimaries &primaries, + QColorSpace::TransferFunction fun, + float gamma) + : gamut(QColorSpace::Gamut::Custom) + , transferFunction(fun) + , gamma(gamma) +{ + Q_ASSERT(primaries.areValid()); + toXyz = primaries.toXyzMatrix(); + whitePoint = QColorVector(primaries.whitePoint); + if (!identifyColorSpace()) + id = QColorSpace::Unknown; + setTransferFunction(); +} + bool QColorSpacePrivate::identifyColorSpace() { switch (gamut) { @@ -195,33 +308,14 @@ void QColorSpacePrivate::initialize() void QColorSpacePrivate::setToXyzMatrix() { - switch (gamut) { - case QColorSpace::Gamut::SRgb: - toXyz = QColorMatrix::toXyzFromSRgb(); - whitePoint = QColorVector::D65(); - return; - case QColorSpace::Gamut::AdobeRgb: - toXyz = QColorMatrix::toXyzFromAdobeRgb(); - whitePoint = QColorVector::D65(); - return; - case QColorSpace::Gamut::DciP3D65: - toXyz = QColorMatrix::toXyzFromDciP3D65(); - whitePoint = QColorVector::D65(); - return; - case QColorSpace::Gamut::ProPhotoRgb: - toXyz = QColorMatrix::toXyzFromProPhotoRgb(); - whitePoint = QColorVector::D50(); - return; - case QColorSpace::Gamut::Bt2020: - toXyz = QColorMatrix::toXyzFromBt2020(); - whitePoint = QColorVector::D65(); - return; - case QColorSpace::Gamut::Custom: + if (gamut == QColorSpace::Gamut::Custom) { toXyz = QColorMatrix::null(); whitePoint = QColorVector::D50(); return; } - Q_UNREACHABLE(); + QColorSpacePrimaries primaries(gamut); + toXyz = primaries.toXyzMatrix(); + whitePoint = QColorVector(primaries.whitePoint); } void QColorSpacePrivate::setTransferFunction() @@ -386,6 +480,23 @@ QColorSpace::QColorSpace(QColorSpace::Gamut gamut, float gamma) { } +/*! + Creates a custom colorspace with a gamut based on the chromaticities of the primary colors \a whitePoint, + \a redPoint, \a greenPoint and \a bluePoint, and using the transfer function \a fun and optionally \a gamma. + */ +QColorSpace::QColorSpace(const QPointF &whitePoint, const QPointF &redPoint, + const QPointF &greenPoint, const QPointF &bluePoint, + QColorSpace::TransferFunction fun, float gamma) +{ + QColorSpacePrimaries primaries(whitePoint, redPoint, greenPoint, bluePoint); + if (!primaries.areValid()) { + qWarning() << "QColorSpace attempted constructed from invalid primaries:" << whitePoint << redPoint << greenPoint << bluePoint; + d_ptr = QColorSpace(QColorSpace::Undefined).d_ptr; + return; + } + d_ptr = new QColorSpacePrivate(primaries, fun, gamma); +} + QColorSpace::~QColorSpace() { } @@ -549,7 +660,7 @@ bool operator==(const QColorSpace &colorSpace1, const QColorSpace &colorSpace2) \fn bool operator!=(const QColorSpace &colorSpace1, const QColorSpace &colorSpace2) \relates QColorSpace - Returns \c true if colorspace \a colorspace1 is not equal to colorspace \a colorspace2; + Returns \c true if colorspace \a colorSpace1 is not equal to colorspace \a colorSpace2; otherwise returns \c false */ |