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Diffstat (limited to 'src/gui/painting/qcolorspace.cpp')
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diff --git a/src/gui/painting/qcolorspace.cpp b/src/gui/painting/qcolorspace.cpp new file mode 100644 index 0000000000..24785f7b61 --- /dev/null +++ b/src/gui/painting/qcolorspace.cpp @@ -0,0 +1,633 @@ +/**************************************************************************** +** +** Copyright (C) 2018 The Qt Company Ltd. +** Contact: https://www.qt.io/licensing/ +** +** This file is part of the QtGui module of the Qt Toolkit. +** +** $QT_BEGIN_LICENSE:LGPL$ +** Commercial License Usage +** Licensees holding valid commercial Qt licenses may use this file in +** accordance with the commercial license agreement provided with the +** Software or, alternatively, in accordance with the terms contained in +** a written agreement between you and The Qt Company. For licensing terms +** and conditions see https://www.qt.io/terms-conditions. For further +** information use the contact form at https://www.qt.io/contact-us. +** +** GNU Lesser General Public License Usage +** Alternatively, this file may be used under the terms of the GNU Lesser +** General Public License version 3 as published by the Free Software +** Foundation and appearing in the file LICENSE.LGPL3 included in the +** packaging of this file. Please review the following information to +** ensure the GNU Lesser General Public License version 3 requirements +** will be met: https://www.gnu.org/licenses/lgpl-3.0.html. +** +** GNU General Public License Usage +** Alternatively, this file may be used under the terms of the GNU +** General Public License version 2.0 or (at your option) the GNU General +** Public license version 3 or any later version approved by the KDE Free +** Qt Foundation. The licenses are as published by the Free Software +** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3 +** included in the packaging of this file. Please review the following +** information to ensure the GNU General Public License requirements will +** be met: https://www.gnu.org/licenses/gpl-2.0.html and +** https://www.gnu.org/licenses/gpl-3.0.html. +** +** $QT_END_LICENSE$ +** +****************************************************************************/ + +#include "qcolorspace.h" +#include "qcolorspace_p.h" + +#include "qcolortransform.h" +#include "qcolormatrix_p.h" +#include "qcolortransferfunction_p.h" +#include "qcolortransform_p.h" +#include "qicc_p.h" + +#include <qmath.h> +#include <qtransform.h> + +#include <qdebug.h> + +QT_BEGIN_NAMESPACE + +QColorSpacePrivate::QColorSpacePrivate() + : id(QColorSpace::Unknown) + , gamut(QColorSpace::Gamut::Custom) + , transferFunction(QColorSpace::TransferFunction::Custom) + , gamma(0.0f) + , whitePoint(QColorVector::null()) + , toXyz(QColorMatrix::null()) +{ +} + +QColorSpacePrivate::QColorSpacePrivate(QColorSpace::ColorSpaceId colorSpaceId) + : id(colorSpaceId) +{ + switch (colorSpaceId) { + case QColorSpace::Undefined: + gamut = QColorSpace::Gamut::Custom; + transferFunction = QColorSpace::TransferFunction::Custom; + gamma = 0.0f; + description = QStringLiteral("Undefined"); + break; + case QColorSpace::SRgb: + gamut = QColorSpace::Gamut::SRgb; + transferFunction = QColorSpace::TransferFunction::SRgb; + gamma = 2.31f; // ? + description = QStringLiteral("sRGB"); + break; + case QColorSpace::SRgbLinear: + gamut = QColorSpace::Gamut::SRgb; + transferFunction = QColorSpace::TransferFunction::Linear; + gamma = 1.0f; + description = QStringLiteral("Linear sRGB"); + break; + case QColorSpace::AdobeRgb: + gamut = QColorSpace::Gamut::AdobeRgb; + transferFunction = QColorSpace::TransferFunction::Gamma; + gamma = 2.19921875f; // Not quite 2.2, see https://www.adobe.com/digitalimag/pdfs/AdobeRGB1998.pdf + description = QStringLiteral("Adobe RGB"); + break; + case QColorSpace::DisplayP3: + gamut = QColorSpace::Gamut::DciP3D65; + transferFunction = QColorSpace::TransferFunction::SRgb; + gamma = 2.31f; // ? + description = QStringLiteral("Display P3"); + break; + case QColorSpace::ProPhotoRgb: + gamut = QColorSpace::Gamut::ProPhotoRgb; + transferFunction = QColorSpace::TransferFunction::ProPhotoRgb; + gamma = 1.8f; + description = QStringLiteral("ProPhoto RGB"); + break; + case QColorSpace::Bt2020: + gamut = QColorSpace::Gamut::Bt2020; + transferFunction = QColorSpace::TransferFunction::Bt2020; + gamma = 2.1f; // ? + description = QStringLiteral("BT.2020"); + break; + case QColorSpace::Unknown: + qWarning("Can not create an unknown color space"); + Q_FALLTHROUGH(); + default: + Q_UNREACHABLE(); + } + initialize(); +} + +QColorSpacePrivate::QColorSpacePrivate(QColorSpace::Gamut gamut, QColorSpace::TransferFunction fun, float gamma) + : gamut(gamut) + , transferFunction(fun) + , gamma(gamma) +{ + if (!identifyColorSpace()) + id = QColorSpace::Unknown; + initialize(); +} + +bool QColorSpacePrivate::identifyColorSpace() +{ + switch (gamut) { + case QColorSpace::Gamut::SRgb: + if (transferFunction == QColorSpace::TransferFunction::SRgb) { + id = QColorSpace::SRgb; + description = QStringLiteral("sRGB"); + return true; + } + if (transferFunction == QColorSpace::TransferFunction::Linear) { + id = QColorSpace::SRgbLinear; + description = QStringLiteral("Linear sRGB"); + return true; + } + break; + case QColorSpace::Gamut::AdobeRgb: + if (transferFunction == QColorSpace::TransferFunction::Gamma) { + if (qAbs(gamma - 2.19921875f) < (1/1024.0f)) { + id = QColorSpace::AdobeRgb; + description = QStringLiteral("Adobe RGB"); + return true; + } + } + break; + case QColorSpace::Gamut::DciP3D65: + if (transferFunction == QColorSpace::TransferFunction::SRgb) { + id = QColorSpace::DisplayP3; + description = QStringLiteral("Display P3"); + return true; + } + break; + case QColorSpace::Gamut::ProPhotoRgb: + if (transferFunction == QColorSpace::TransferFunction::ProPhotoRgb) { + id = QColorSpace::ProPhotoRgb; + description = QStringLiteral("ProPhoto RGB"); + return true; + } + if (transferFunction == QColorSpace::TransferFunction::Gamma) { + // ProPhoto RGB's curve is effectively gamma 1.8 for 8bit precision. + if (qAbs(gamma - 1.8f) < (1/1024.0f)) { + id = QColorSpace::ProPhotoRgb; + description = QStringLiteral("ProPhoto RGB"); + return true; + } + } + break; + case QColorSpace::Gamut::Bt2020: + if (transferFunction == QColorSpace::TransferFunction::Bt2020) { + id = QColorSpace::Bt2020; + description = QStringLiteral("BT.2020"); + return true; + } + break; + default: + break; + } + return false; +} + +void QColorSpacePrivate::initialize() +{ + setToXyzMatrix(); + setTransferFunction(); +} + +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: + toXyz = QColorMatrix::null(); + whitePoint = QColorVector::D50(); + return; + } + Q_UNREACHABLE(); +} + +void QColorSpacePrivate::setTransferFunction() +{ + switch (transferFunction) { + case QColorSpace::TransferFunction::Linear: + trc[0].m_type = QColorTrc::Type::Function; + trc[0].m_fun = QColorTransferFunction(); + break; + case QColorSpace::TransferFunction::Gamma: + trc[0].m_type = QColorTrc::Type::Function; + trc[0].m_fun = QColorTransferFunction::fromGamma(gamma); + break; + case QColorSpace::TransferFunction::SRgb: + trc[0].m_type = QColorTrc::Type::Function; + trc[0].m_fun = QColorTransferFunction::fromSRgb(); + break; + case QColorSpace::TransferFunction::ProPhotoRgb: + trc[0].m_type = QColorTrc::Type::Function; + trc[0].m_fun = QColorTransferFunction::fromProPhotoRgb(); + break; + case QColorSpace::TransferFunction::Bt2020: + trc[0].m_type = QColorTrc::Type::Function; + trc[0].m_fun = QColorTransferFunction::fromBt2020(); + break; + case QColorSpace::TransferFunction::Custom: + break; + default: + Q_UNREACHABLE(); + break; + } + trc[1] = trc[0]; + trc[2] = trc[0]; +} + +QColorTransform QColorSpacePrivate::transformationToColorSpace(const QColorSpacePrivate *out) const +{ + Q_ASSERT(out); + QColorTransform combined; + combined.d_ptr.reset(new QColorTransformPrivate); + combined.d_ptr->colorSpaceIn = this; + combined.d_ptr->colorSpaceOut = out; + combined.d_ptr->colorMatrix = out->toXyz.inverted() * toXyz; + return combined; +} + +/*! + \class QColorSpace + \brief The QColorSpace class provides a color space abstraction. + \since 5.14 + + \ingroup painting + \ingroup appearance + \inmodule QtGui + + Color values can be interpreted in different ways, and based on the interpretation + can live in different spaces. We call this \e {color spaces}. + + QColorSpace provides access to creating several predefined color spaces and + can generate QColorTransforms for converting colors from one color space to + another. + + QColorSpace can also represent color spaces defined by ICC profiles or embedded + in images, that do not otherwise fit the predefined color spaces. + + A color space can generally speaking be conceived as a combination of a transfer + function and a gamut. The gamut defines which colors the color space can represent. + A color space that can represent a wider range of colors is also known as a + wide-gamut color space. The gamut is defined by three primary colors that represent + exactly how red, green, and blue look in this particular color space, and a white + color that represents where and how bright pure white is. + + The transfer function or gamma curve determines how each component in the + color space is encoded. These are used because human perception does not operate + linearly, and the transfer functions try to ensure that colors will seem evenly + spaced to human eyes. +*/ + + +/*! + \enum QColorSpace::ColorSpaceId + + Predefined color spaces. + + \value Undefined An empty, invalid or unsupported color space. + \value Unknown A valid color space that doesn't match any of the predefined color spaces. + \value SRgb The sRGB color space, which Qt operates in by default. It is a close approximation + of how most classic monitors operate, and a mode most software and hardware support. + \l{http://www.color.org/chardata/rgb/srgb.xalter}{ICC registration of sRGB}. + \value SRgbLinear The sRGB color space with linear gamma. Useful for gamma-corrected blending. + \value AdobeRgb The Adobe RGB color space is a classic wide-gamut color space, using a gamma of 2.2. + \l{http://www.color.org/chardata/rgb/adobergb.xalter}{ICC registration of Adobe RGB (1998)} + \value DisplayP3 A color-space using the primaries of DCI-P3, but with the whitepoint and transfer + function of sRGB. Common in modern wide-gamut screens. + \l{http://www.color.org/chardata/rgb/DCIP3.xalter}{ICC registration of DCI-P3} + \value ProPhotoRgb The Pro Photo RGB color space, also known as ROMM RGB is a very wide gamut color space. + \l{http://www.color.org/chardata/rgb/rommrgb.xalter}{ICC registration of ROMM RGB} + \value Bt2020 BT.2020 also known as Rec.2020 is the color space of HDR TVs. + \l{http://www.color.org/chardata/rgb/BT2020.xalter}{ICC registration of BT.2020} +*/ + +/*! + \enum QColorSpace::Gamut + + Predefined gamuts, or sets of primary colors. + + \value Custom The gamut is undefined or does not match any predefined sets. + \value SRgb The sRGB gamut + \value AdobeRgb The Adobe RGB gamut + \value DciP3D65 The DCI-P3 gamut with the D65 whitepoint + \value ProPhotoRgb The ProPhoto RGB gamut with the D50 whitepoint + \value Bt2020 The BT.2020 gamut +*/ + +/*! + \enum QColorSpace::TransferFunction + + Predefined transfer functions or gamma curves. + + \value Custom The custom or null transfer function + \value Linear The linear transfer functions + \value Gamma A transfer function that is a real gamma curve based on the value of gamma() + \value SRgb The sRGB transfer function, composed of linear and gamma parts + \value ProPhotoRgb The ProPhoto RGB transfer function, composed of linear and gamma parts + \value Bt2020 The BT.2020 transfer function, composed of linear and gamma parts +*/ + +/*! + Creates a new colorspace object that represents \a colorSpaceId. + */ +QColorSpace::QColorSpace(QColorSpace::ColorSpaceId colorSpaceId) +{ + static QExplicitlySharedDataPointer<QColorSpacePrivate> predefinedColorspacePrivates[QColorSpace::Bt2020]; + if (colorSpaceId <= QColorSpace::Unknown) { + if (!predefinedColorspacePrivates[0]) + predefinedColorspacePrivates[0] = new QColorSpacePrivate(QColorSpace::Undefined); + d_ptr = predefinedColorspacePrivates[0]; // unknown and undefined both returns the static undefined colorspace. + } else { + if (!predefinedColorspacePrivates[colorSpaceId - 1]) + predefinedColorspacePrivates[colorSpaceId - 1] = new QColorSpacePrivate(colorSpaceId); + d_ptr = predefinedColorspacePrivates[colorSpaceId - 1]; + } + + Q_ASSERT(colorSpaceId == QColorSpace::Undefined || isValid()); +} + +/*! + Creates a custom color space with the gamut \a gamut, using the transfer function \a fun and + optionally \a gamma. + */ +QColorSpace::QColorSpace(QColorSpace::Gamut gamut, QColorSpace::TransferFunction fun, float gamma) + : d_ptr(new QColorSpacePrivate(gamut, fun, gamma)) +{ +} + +/*! + Creates a custom color space with the gamut \a gamut, using a gamma transfer function of + \a gamma. + */ +QColorSpace::QColorSpace(QColorSpace::Gamut gamut, float gamma) + : d_ptr(new QColorSpacePrivate(gamut, TransferFunction::Gamma, gamma)) +{ +} + +QColorSpace::~QColorSpace() +{ +} + +QColorSpace::QColorSpace(QColorSpace &&colorSpace) + : d_ptr(std::move(colorSpace.d_ptr)) +{ +} + +QColorSpace::QColorSpace(const QColorSpace &colorSpace) + : d_ptr(colorSpace.d_ptr) +{ +} + +QColorSpace &QColorSpace::operator=(QColorSpace &&colorSpace) +{ + d_ptr = std::move(colorSpace.d_ptr); + return *this; +} + +QColorSpace &QColorSpace::operator=(const QColorSpace &colorSpace) +{ + d_ptr = colorSpace.d_ptr; + return *this; +} + +/*! + Returns the id of the predefined color space this object + represents or \c Unknown if it doesn't match any of them. +*/ +QColorSpace::ColorSpaceId QColorSpace::colorSpaceId() const noexcept +{ + return d_ptr->id; +} + +/*! + Returns the predefined gamut of the color space + or \c Gamut::Custom if it doesn't match any of them. +*/ +QColorSpace::Gamut QColorSpace::gamut() const noexcept +{ + return d_ptr->gamut; +} + +/*! + Returns the predefined transfer function of the color space + or \c TransferFunction::Custom if it doesn't match any of them. + + \sa gamma() +*/ +QColorSpace::TransferFunction QColorSpace::transferFunction() const noexcept +{ + return d_ptr->transferFunction; +} + +/*! + Returns the gamma value of color spaces with \c TransferFunction::Gamma, + an approximate gamma value for other predefined color spaces, or + 0.0 if no approximate gamma is known. + + \sa transferFunction() +*/ +float QColorSpace::gamma() const noexcept +{ + return d_ptr->gamma; +} + +/*! + Returns an ICC profile representing the color space. + + If the color space was generated from an ICC profile, that profile + is returned, otherwise one is generated. + + \note Even invalid color spaces may return the ICC profile if they + were generated from one, to allow applications to implement wider + support themselves. + + \sa fromIccProfile() +*/ +QByteArray QColorSpace::iccProfile() const +{ + if (!d_ptr->iccProfile.isEmpty()) + return d_ptr->iccProfile; + if (!isValid()) + return QByteArray(); + return QIcc::toIccProfile(*this); +} + +/*! + Creates a QColorSpace from ICC profile \a iccProfile. + + \note Not all ICC profiles are supported. QColorSpace only supports + RGB-XYZ ICC profiles that are three-component matrix-based. + + If the ICC profile is not supported an invalid QColorSpace is returned + where you can still read the original ICC profile using iccProfile(). + + \sa iccProfile() +*/ +QColorSpace QColorSpace::fromIccProfile(const QByteArray &iccProfile) +{ + QColorSpace colorSpace; + if (QIcc::fromIccProfile(iccProfile, &colorSpace)) + return colorSpace; + colorSpace.d_ptr->id = QColorSpace::Undefined; + colorSpace.d_ptr->iccProfile = iccProfile; + return colorSpace; +} + +/*! + Returns \c true if the color space is valid. +*/ +bool QColorSpace::isValid() const noexcept +{ + return d_ptr->id != QColorSpace::Undefined && d_ptr->toXyz.isValid() + && d_ptr->trc[0].isValid() && d_ptr->trc[1].isValid() && d_ptr->trc[2].isValid(); +} + +/*! + \relates QColorSpace + Returns \c true if colorspace \a colorSpace1 is equal to colorspace \a colorSpace2; + otherwise returns \c false +*/ +bool operator==(const QColorSpace &colorSpace1, const QColorSpace &colorSpace2) +{ + if (colorSpace1.d_ptr == colorSpace2.d_ptr) + return true; + + if (colorSpace1.colorSpaceId() == QColorSpace::Undefined && colorSpace2.colorSpaceId() == QColorSpace::Undefined) + return colorSpace1.d_ptr->iccProfile == colorSpace2.d_ptr->iccProfile; + + if (colorSpace1.colorSpaceId() != QColorSpace::Unknown && colorSpace2.colorSpaceId() != QColorSpace::Unknown) + return colorSpace1.colorSpaceId() == colorSpace2.colorSpaceId(); + + if (colorSpace1.gamut() != QColorSpace::Gamut::Custom && colorSpace2.gamut() != QColorSpace::Gamut::Custom) { + if (colorSpace1.gamut() != colorSpace2.gamut()) + return false; + } else { + if (colorSpace1.d_ptr->toXyz != colorSpace2.d_ptr->toXyz) + return false; + } + + if (colorSpace1.transferFunction() != QColorSpace::TransferFunction::Custom && + colorSpace2.transferFunction() != QColorSpace::TransferFunction::Custom) { + if (colorSpace1.transferFunction() != colorSpace2.transferFunction()) + return false; + if (colorSpace1.transferFunction() == QColorSpace::TransferFunction::Gamma) + return colorSpace1.gamma() == colorSpace2.gamma(); + return true; + } + + if (colorSpace1.d_ptr->trc[0] != colorSpace2.d_ptr->trc[0] || + colorSpace1.d_ptr->trc[1] != colorSpace2.d_ptr->trc[1] || + colorSpace1.d_ptr->trc[2] != colorSpace2.d_ptr->trc[2]) + return false; + + return true; +} + +/*! + \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; + otherwise returns \c false +*/ + +/*! + Generates and returns a color space transformation from this color space to + \a colorspace. +*/ +QColorTransform QColorSpace::transformationToColorSpace(const QColorSpace &colorspace) const +{ + if (!isValid() || !colorspace.isValid()) + return QColorTransform(); + + return d_ptr->transformationToColorSpace(colorspace.d_ptr.constData()); +} + +/*! + \internal +*/ +QColorSpacePrivate *QColorSpace::d_func() +{ + d_ptr.detach(); + return d_ptr.data(); +} + +/*! + \fn const QColorSpacePrivate* QColorSpacePrivate::d_func() const + \internal +*/ + +/***************************************************************************** + QColorSpace stream functions + *****************************************************************************/ +#if !defined(QT_NO_DATASTREAM) +/*! + \fn QDataStream &operator<<(QDataStream &stream, const QColorSpace &colorSpace) + \relates QColorSpace + + Writes the given \a colorSpace to the given \a stream as an ICC profile. + + \sa QColorSpace::iccProfile(), {Serializing Qt Data Types} +*/ + +QDataStream &operator<<(QDataStream &s, const QColorSpace &image) +{ + s << image.iccProfile(); + return s; +} + +/*! + \fn QDataStream &operator>>(QDataStream &stream, QColorSpace &colorSpace) + \relates QColorSpace + + Reads a color space from the given \a stream and stores it in the given + \a colorSpace. + + \sa QColorSpace::fromIccProfile(), {Serializing Qt Data Types} +*/ + +QDataStream &operator>>(QDataStream &s, QColorSpace &colorSpace) +{ + QByteArray iccProfile; + s >> iccProfile; + colorSpace = QColorSpace::fromIccProfile(iccProfile); + return s; +} +#endif // QT_NO_DATASTREAM + +#ifndef QT_NO_DEBUG_STREAM +QDebug operator<<(QDebug dbg, const QColorSpace &colorSpace) +{ + QDebugStateSaver saver(dbg); + dbg.nospace(); + dbg << "QColorSpace("; + dbg << colorSpace.colorSpaceId() << ", " << colorSpace.gamut() << ", " << colorSpace.transferFunction(); + dbg << ", gamma=" << colorSpace.gamma(); + dbg << ')'; + return dbg; +} +#endif + +QT_END_NAMESPACE |