PerceptualColor Namespace Reference

Classes
class	AbstractDiagram
class	ChromaHueDiagram
class	ColorDialog
class	ColorPatch
class	ColorWheel
class	GradientSlider
class	MultiSpinBox
class	MultiSpinBoxSection
class	RgbColorSpaceFactory
class	WheelColorPicker

Typedefs
using	QColorFloatType = decltype(std::declval<QColor>().redF())
using	QListSizeType = decltype(std::declval<QList<int>>().count())
using	QStringLength = decltype(std::declval<QString>().length())
using	QStringSize = decltype(std::declval<QString>().size())
using	Quartet = QGenericMatrix<1, 4, double>
using	SquareMatrix3 = QGenericMatrix<3, 3, double>
using	Swatches = Array2D<QColor>
using	Trio = QGenericMatrix<1, 3, double>

Enumerations
enum class	ColorModel {   CielabD50 , CielchD50 , Hsl360_1_1 , Hwb360_1_1 ,   Invalid , OklabD65 , OklchD65 , Rgb1 ,   XyzD50 , XyzD65 }
enum class	ColorSchemeType { Light , Dark }

Functions
template<int N, int M, typename T, typename... Args>
constexpr QGenericMatrix< N, M, T >	createMatrix (Args... args)
SquareMatrix3	createSquareMatrix3 (double r0c0, double r0c1, double r0c2, double r1c0, double r1c1, double r1c2, double r2c0, double r2c1, double r2c2)
Trio	createTrio (double first, double second, double third)
int	decimalPlaces (const int rangeMax, const int significantFigures)
template<typename T = void>
void	delayedEventProcessing (unsigned long msecWaitInitially=50, unsigned long msecWaitBetweenEventLoopPasses=50, int numberEventLoopPasses=3)
void	doAntialias (QImage &image, const QList< QPoint > &antiAliasCoordinates, const std::function< QRgb(const double x, const double y)> &colorFunction)
void	drawQWidgetStyleSheetAware (QWidget *widget)
template<typename T>
QString	enumerationToFullString ()
template<typename T>
QString	enumeratorToFullString (const T &enumerator)
template<typename T>
QString	enumeratorToString (const T &enumerator)
QList< QPoint >	findBoundary (const QImage &image)
template<typename T>
constexpr quint8	fromFloatingToEightBit (const T &original)
QString	fromMnemonicToRichText (const QString &mnemonicText)
QPair< QString, QString >	getPrefixSuffix (const QString &formatString)
ColorSchemeType	guessColorSchemeTypeFromWidget (QWidget *widget)
void	initializeLibraryResources ()
void	initializeTranslation (QCoreApplication *instance, std::optional< QStringList > newUiLanguages)
std::optional< SquareMatrix3 >	inverseMatrix (const SquareMatrix3 &matrix)
template<typename First, typename... T>
bool	isIn (First &&first, T &&...t)
template<typename A, typename B>
constexpr bool	isNearlyEqual (A a, B b)
template<typename T>
constexpr bool	isNearlyEqual (T a, T b, T epsilon)
template<typename T>
constexpr bool	isOdd (const T &number)
QMap< cmsUInt32Number, QString >	lcmsIntentList ()
template<typename T>
T	normalizedAngle360 (T value)
template<typename T>
void	normalizePolar360 (T &radius, T &angleDegree)
QDebug	operator<< (QDebug dbg, const PerceptualColor::GenericColor &value)
QDebug	operator<< (QDebug dbg, const PerceptualColor::MultiSpinBoxSection &value)
QDebug	operator<< (QDebug dbg, const PerceptualColor::PolarPointF value)
QDebug	operator<< (QDebug dbg, const PerceptualColor::RgbColor &value)
QVersionNumber	perceptualColorRunTimeVersion ()
template<typename T>
QColor	qColorFromRgbDouble (T red, T green, T blue)
QIcon	qIconFromTheme (const QStringList &names, const QString &fallback, ColorSchemeType type)
template<typename T>
constexpr T	roundToDigits (T value, int precision)
void	setTranslation (QCoreApplication *instance, const QStringList &newUiLanguages)
qreal	standardWheelStepCount (QWheelEvent *event)
cmsCIELab	toCmsLab (const cmsCIELCh &value)
GenericColor	toGenericColorCielabD50 (const cmsCIELab &value)
QImage	transparencyBackground (qreal devicePixelRatioF)
Swatches	wcsBasicColors (const QSharedPointer< PerceptualColor::RgbColorSpace > &colorSpace)

Variables
constexpr qreal	gamutPrecisionCielab = 0.001
constexpr qreal	gamutPrecisionOklab = gamutPrecisionCielab / 100
constexpr int	overlap = 2
constexpr qreal	pageStepAlpha = 10 * singleStepAlpha
constexpr int	pageStepChroma = 10 * singleStepChroma
constexpr int	pageStepHue = 10 * singleStepHue
constexpr int	pageStepLightness = 10 * singleStepLightness
constexpr auto	pi = M_PI
const QString	richTextMarker = QStringLiteral(u"<a/>")
constexpr qreal	scaleFromMinumumSizeHintToSizeHint = 1.2
constexpr qreal	singleStepAlpha = 0.01
constexpr int	singleStepChroma = 1
constexpr int	singleStepHue = 360 / 100
constexpr int	singleStepLightness = 1
constexpr double	singleStepOklabc = 0.01
constexpr cmsCIEXYZ	whitePointD65TwoDegree {0.95047, 1.00000, 1.08883}

Detailed Description

The namespace of this library.

All symbols that are provided in this library are encapsulated within this namespace.

Typedef Documentation

QColorFloatType

using PerceptualColor::QColorFloatType = decltype(std::declval<QColor>().redF())

Definition at line 27 of file helperqttypes.h.

QListSizeType

using PerceptualColor::QListSizeType = decltype(std::declval<QList<int>>().count())

Definition at line 65 of file helperqttypes.h.

QStringLength

using PerceptualColor::QStringLength = decltype(std::declval<QString>().length())

Definition at line 82 of file helperqttypes.h.

QStringSize

using PerceptualColor::QStringSize = decltype(std::declval<QString>().size())

Definition at line 95 of file helperqttypes.h.

Quartet

using PerceptualColor::Quartet = QGenericMatrix<1, 4, double>

Definition at line 34 of file helpermath.h.

SquareMatrix3

using PerceptualColor::SquareMatrix3 = QGenericMatrix<3, 3, double>

Definition at line 45 of file helpermath.h.

Swatches

using PerceptualColor::Swatches = Array2D<QColor>

Swatches organized in a grid.

This type is declared as type to Qt’s type system via Q_DECLARE_METATYPE. Depending on your use case (for example if you want to use for queued signal-slot connections), you might consider calling qRegisterMetaType() for this type, once you have a QApplication object.

Definition at line 262 of file helper.h.

Trio

using PerceptualColor::Trio = QGenericMatrix<1, 3, double>

Definition at line 58 of file helpermath.h.

Enumeration Type Documentation

ColorModel

enum class PerceptualColor::ColorModel

strong

Identifiers for color models.

Enumerator
CielabD50	The absolute Cielab color space using a D50 illuminant. Lightness: [0, 100]. a: unbound. b: unbound.
CielchD50	The absolute Cielch color space using a D50 illuminant. Lightness: [0, 100]. Chroma: unbound. Hue: [0, 360[.
Hsl360_1_1	Any color space using the HSL color model, which is a transformation of the RGB color model. Color values only have a well-defined absolute meaning when associated with a corresponding RGB color profile. Hue: [0, 360[. Saturation: [0, 1]. Lightness: [0, 1].
Hwb360_1_1	Any color space using the HSL color model, which is a transformation of the HWB color model. Color values only have a well-defined absolute meaning when associated with a corresponding RGB color profile. Hue: [0, 360[. Whiteness: [0, 1]. Blackness: [0, 1].
Invalid	Represents invalid data.
OklabD65	The absolute Oklab color space, which by definition always and exclusively uses a D65 illuminant. Lightness: [0, 1]. a: unbound. b: unbound.
OklchD65	The absolute Oklch color space, which by definition always and exclusively uses a D65 illuminant. Lightness: [0, 1]. Chroma: unbound. Hue: [0, 360[.
Rgb1	Any color space using the RGB color model. Color values only have a well-defined absolute meaning when associated with a corresponding RGB color profile. R: [0, 1]. G: [0, 1]. B: [0, 1].
XyzD50	The absolute XYZ color space assuming chromatic adaption for the D50 illuminant. X: unbound. Y: [0, 1]. Diffuse white has a luminance (Y) of 1.0 Z: unbound.
XyzD65	The absolute XYZ color space assuming chromatic adaption for the D65 illuminant. X: unbound. Y: [0, 1]. Diffuse white has a luminance (Y) of 1.0 Z: unbound.

Definition at line 38 of file helperconversion.h.

ColorSchemeType

enum class PerceptualColor::ColorSchemeType

strong

Represents the appearance of a theme.

Todo

Substitute this by enum class Qt::ColorScheme which is available since Qt 6.

Enumerator
Light	Light theme.
Dark	Dark theme.

Definition at line 41 of file helper.h.

Function Documentation

createMatrix()

template<int N, int M, typename T, typename... Args>

QGenericMatrix< N, M, T > PerceptualColor::createMatrix ( Args... args )

nodiscardconstexpr

Definition at line 72 of file helpermath.h.

createSquareMatrix3()

SquareMatrix3 PerceptualColor::createSquareMatrix3	(	double	r0c0,
		double	r0c1,
		double	r0c2,
		double	r1c0,
		double	r1c1,
		double	r1c2,
		double	r2c0,
		double	r2c1,
		double	r2c2 )

Definition at line 29 of file helpermath.cpp.

createTrio()

Trio PerceptualColor::createTrio	(	double	first,
		double	second,
		double	third )

Definition at line 48 of file helpermath.cpp.

decimalPlaces()

int PerceptualColor::decimalPlaces	(	const int	rangeMax,
		const int	significantFigures )

Calculates the required number of decimals to achieve the requested number of significant figures within the given range.

Parameters

rangeMax	The maximum value of the range [0, rangeMax].
significantFigures	The requested number of significant figures.

maxRange	decimalPlaces(maxRange, 2)	decimalPlaces(maxRange, 3)	decimalPlaces(maxRange, 4)
1	1	2	3
2	1	2	3
100	0	0	1
255	0	0	1
360	0	0	1

Returns

The number of decimal places after the decimal point (in addition to the whole number part) required to achieve the requested number of significant figures within the given range.

Definition at line 108 of file helpermath.cpp.

delayedEventProcessing()

template<typename T = void>

void PerceptualColor::delayedEventProcessing	(	unsigned long	msecWaitInitially = 50,
		unsigned long	msecWaitBetweenEventLoopPasses = 50,
		int	numberEventLoopPasses = 3 )

Definition at line 286 of file helper.h.

doAntialias()

void PerceptualColor::doAntialias	(	QImage &	image,
		const QList< QPoint > &	antiAliasCoordinates,
		const std::function< QRgb(const double x, const double y)> &	colorFunction )

Calculates anti-alias for gamut diagrams.

Gamut images generated by this library typically exhibit sharp boundaries, where a pixel is either within the gamut (opaque color) or outside it (transparent color). The determination is based on the coordinates at the center of the pixel's square surface.

This function is designed to perform anti-aliasing by smoothing the sharp gamut boundaries. To use this function, first obtain a list of candidate pixels for anti-aliasing. These are the pixels surrounding the sharp gamut border, which can be identified using findBoundary(). This function then calculates, within the 1 px × 1 px area of each candidate pixel, multiple data points at a significantly higher resolution than the single data point in the original image. By analyzing this detailed data, the function applies anti-aliasing to smooth the boundary.

Note

Since this operation is computationally intensive, it is recommended to apply it only to the pixels returned by findBoundary(), rather than the entire image.

Parameters

image	The image that should be modified.
antiAliasCoordinates	A list of pixels for which anti-aliasing should be done.
colorFunction	A pointer to a function that returns the opaque color for the given coordinates, or a transparent color if out-of-gamut.

Definition at line 127 of file helperimage.cpp.

drawQWidgetStyleSheetAware()

void PerceptualColor::drawQWidgetStyleSheetAware

(

QWidget *

widget

)

Definition at line 145 of file helper.cpp.

enumerationToFullString()

template<typename T>

QString PerceptualColor::enumerationToFullString ( )

nodiscard

The full-qualified C++ identifier as QString.

This can be useful for debugging purposes.

Template Parameters

T	The enumeration.

Precondition

The enumeration type is declared with Q_ENUM or Q_ENUM_NS.

Returns

The full-qualified C++ identifier as QString.

Definition at line 322 of file helper.h.

enumeratorToFullString()

template<typename T>

QString PerceptualColor::enumeratorToFullString ( const T & enumerator )

nodiscard

The full-qualified C++ identifier as QString.

This can be useful for debugging purposes.

Template Parameters

T	The enumeration type. Can usually be omitted.

Parameters

enumerator

An enumerator.

Precondition

The enumeration type of the enumerator is declared with Q_ENUM or Q_ENUM_NS.

Returns

The full-qualified C++ identifier as QString, followed by the underlying integer value in parenthesis. If the enumerator does not exist (for example because you have done a static_cast of an invalid integer to the enum class), an empty String is returned instead. If the enumerator has synonyms (that means, there exist other enumerators that share the same integer with the current enumerator), all synonym enumerators are returned.

See also

enumeratorToString()

Definition at line 351 of file helper.h.

enumeratorToString()

template<typename T>

QString PerceptualColor::enumeratorToString ( const T & enumerator )

nodiscard

The C++ identifier as QString.

This can be useful for debugging purposes.

Template Parameters

T	The enumeration type. Can usually be omitted.

Parameters

enumerator

An enumerator.

Precondition

The enumeration type of the enumerator is declared with Q_ENUM or Q_ENUM_NS.

Returns

The C++ identifier as QString, followed by the underlying integer value in parenthesis. If the enumerator does not exist (for example because you have done a static_cast of an invalid integer to the enum class), an empty String is returned instead. If the enumerator has synonyms (that means, there exist other enumerators that share the same integer with the current enumerator), all synonym enumerators are returned.

See also

enumeratorToFullString()

Definition at line 393 of file helper.h.

findBoundary()

QList< QPoint > PerceptualColor::findBoundary ( const QImage & image )

nodiscard

Find boundaries between fully opaque and fully transparent pixels.

Parameters

image

The image to be searched.

Note

There is no API guarantee regarding the handling of partially transparent pixels — they may be treated as fully opaque or fully transparent.

Returns

A list of all coordinate points on both sides of the boundary.

Note

This function is thread-save as long as there is no more than one thread of this function operating on the same data on the same time.

Definition at line 42 of file helperimage.cpp.

fromFloatingToEightBit()

template<typename T>

quint8 PerceptualColor::fromFloatingToEightBit ( const T & original )

nodiscardconstexpr

Definition at line 111 of file helperconversion.h.

fromMnemonicToRichText()

QString PerceptualColor::fromMnemonicToRichText

(

const QString &

mnemonicText

)

Definition at line 256 of file helper.cpp.

getPrefixSuffix()

QPair< QString, QString > PerceptualColor::getPrefixSuffix ( const QString & formatString )

nodiscard

Definition at line 179 of file helper.cpp.

guessColorSchemeTypeFromWidget()

ColorSchemeType PerceptualColor::guessColorSchemeTypeFromWidget

(

QWidget *

widget

)

Definition at line 329 of file helper.cpp.

initializeLibraryResources()

void PerceptualColor::initializeLibraryResources

(

)

Definition at line 47 of file initializelibraryresources.cpp.

initializeTranslation()

void PerceptualColor::initializeTranslation	(	QCoreApplication *	instance,
		std::optional< QStringList >	newUiLanguages )

Definition at line 73 of file initializetranslation.cpp.

inverseMatrix()

std::optional< SquareMatrix3 > PerceptualColor::inverseMatrix

(

const SquareMatrix3 &

matrix

)

Definition at line 62 of file helpermath.cpp.

isIn()

template<typename First, typename... T>

bool PerceptualColor::isIn	(	First &&	first,
		T &&...	t )

Definition at line 66 of file helper.h.

isNearlyEqual() [1/2]

template<typename A, typename B>

bool PerceptualColor::isNearlyEqual ( A a, B b )

nodiscardconstexpr

Definition at line 188 of file helpermath.h.

isNearlyEqual() [2/2]

template<typename T>

bool PerceptualColor::isNearlyEqual ( T a, T b, T epsilon )

nodiscardconstexpr

Definition at line 151 of file helpermath.h.

isOdd()

template<typename T>

bool PerceptualColor::isOdd ( const T & number )

nodiscardconstexpr

Definition at line 119 of file helpermath.h.

lcmsIntentList()

QMap< cmsUInt32Number, QString > PerceptualColor::lcmsIntentList

(

)

The rendering intents supported by the LittleCMS library.

Contains all rendering intents supported by the LittleCMS library against which this we are currently linking (or by one of the LittleCMS library plugigs). Each entry contains the code and the description (english-language, might be empty) just as provided by LittleCMS’ cmsGetSupportedIntents().

Note that LittleCMS supports as built-in intents the four official ICC intents and also some other, non-ICC intents. Furthermore, LittleCMS plugins can provide even more intents. As of LittleCMS 2.13 the following built-in intents are available:

Type	Macro name	Code
ICC	INTENT_PERCEPTUAL	0
ICC	INTENT_RELATIVE_COLORIMETRIC	1
ICC	INTENT_SATURATION	2
ICC	INTENT_ABSOLUTE_COLORIMETRIC	3
Non-ICC	INTENT_PRESERVE_K_ONLY_PERCEPTUAL	10
Non-ICC	INTENT_PRESERVE_K_ONLY_RELATIVE_COLORIMETRIC	11
Non-ICC	INTENT_PRESERVE_K_ONLY_SATURATION	12
Non-ICC	INTENT_PRESERVE_K_PLANE_PERCEPTUAL	13
Non-ICC	INTENT_PRESERVE_K_PLANE_RELATIVE_COLORIMETRIC	14
Non-ICC	INTENT_PRESERVE_K_PLANE_SATURATION	15

Returns

A QMap of key-value pairs. The key is the code representing the rendering intent. The value is a QString with the description.

Definition at line 578 of file helper.cpp.

normalizedAngle360()

template<typename T>

T PerceptualColor::normalizedAngle360

(

T

value

)

Definition at line 252 of file helpermath.h.

normalizePolar360()

template<typename T>

void PerceptualColor::normalizePolar360	(	T &	radius,
		T &	angleDegree )

Definition at line 280 of file helpermath.h.

operator<<() [1/4]

QDebug PerceptualColor::operator<<	(	QDebug	dbg,
		const PerceptualColor::GenericColor &	value )

Definition at line 104 of file genericcolor.cpp.

operator<<() [2/4]

PERCEPTUALCOLOR_IMPORTEXPORT QDebug PerceptualColor::operator<<	(	QDebug	dbg,
		const PerceptualColor::MultiSpinBoxSection &	value )

Adds QDebug() support for data type PerceptualColor::MultiSpinBoxSection.

Parameters

dbg	Existing debug object
value	Value to stream into the debug object

Returns

Debug object with value streamed in

Definition at line 245 of file multispinboxsection.cpp.

operator<<() [3/4]

QDebug PerceptualColor::operator<<	(	QDebug	dbg,
		const PerceptualColor::PolarPointF	value )

Definition at line 116 of file polarpointf.cpp.

operator<<() [4/4]

QDebug PerceptualColor::operator<<	(	QDebug	dbg,
		const PerceptualColor::RgbColor &	value )

Definition at line 251 of file rgbcolor.cpp.

perceptualColorRunTimeVersion()

PERCEPTUALCOLOR_IMPORTEXPORT QVersionNumber PerceptualColor::perceptualColorRunTimeVersion ( )

nodiscard

Against which version of this library you are running.

Returns

The library version with major, minor and patch version. Note that there is no pre-release identifier included. For example, if your application is running against version 1.2.3-alpha of this library, this function will return QVersionNumber(1, 2, 3).

To use this function, include version.h

See also

Version information at compiletime and runtime

Definition at line 33 of file version.cpp.

qColorFromRgbDouble()

template<typename T>

QColor PerceptualColor::qColorFromRgbDouble ( T red, T green, T blue )

nodiscard

Definition at line 130 of file helperconversion.h.

qIconFromTheme()

QIcon PerceptualColor::qIconFromTheme ( const QStringList & names, const QString & fallback, ColorSchemeType type )

nodiscard

Definition at line 204 of file helper.cpp.

roundToDigits()

template<typename T>

T PerceptualColor::roundToDigits ( T value, int precision )

nodiscardconstexpr

Definition at line 299 of file helpermath.h.

setTranslation()

void PERCEPTUALCOLOR_IMPORTEXPORT PerceptualColor::setTranslation	(	QCoreApplication *	instance,
		const QStringList &	newUiLanguages )

Set the translation for the whole library.

After calling this function, all objects of this library that are created from now on are translated according to translation that was set.

Objects that were yet existing when calling are not always automatically updated: When calling this function, Qt sends a QEvent::LanguageChange event only to top-level widgets, and these will get updated then. You can send the event yourself to non-top-level widgets to update those widgets also. Note that also RgbColorSpaceFactory generates objects that might have localized properties; these objects do not support translation updates.

If you create objects that use translations before a translation has been set explicitly, than automatically an environment-dependant translation is loaded.

You might call this function again after a change of QLocale() to change the translation. Also, call this function again after destroying the QCoreApplication object and creating a new one.

It is safe to call this function multiple times.

Precondition

There exists exactly one instance of QCoreApplication to which the parameter points. This function is called from the same thread in which the QCoreApplication instance lives.

Parameters

instance	A pointer to the QCoreApplication instance for which the initialization will be done.
newUiLanguages	List of translations, ordered by priority, most important ones first, like in QLocale::uiLanguages().

Definition at line 55 of file settranslation.cpp.

standardWheelStepCount()

qreal PerceptualColor::standardWheelStepCount ( QWheelEvent * event )

nodiscard

Definition at line 62 of file helper.cpp.

toCmsLab()

cmsCIELab PerceptualColor::toCmsLab ( const cmsCIELCh & value )

nodiscard

Definition at line 33 of file helperconversion.cpp.

toGenericColorCielabD50()

GenericColor PerceptualColor::toGenericColorCielabD50 ( const cmsCIELab & value )

nodiscard

Definition at line 21 of file helperconversion.cpp.

transparencyBackground()

QImage PerceptualColor::transparencyBackground ( qreal devicePixelRatioF )

nodiscard

Definition at line 104 of file helper.cpp.

wcsBasicColors()

Swatches PerceptualColor::wcsBasicColors ( const QSharedPointer< PerceptualColor::RgbColorSpace > & colorSpace )

nodiscard

Swatch grid derived from the basic colors as by WCS (World color survey).

The swatch grid contains various tints and shades of the basic colors. The choice of the basic colors is based on the study by Brent Berlin and Paul Kay, who suggest that the basic color terms in almost all languages on earth follow a universal pattern. They propose that there are eleven basic color terms that appear in this order during the evolution of a language:

1. black, white
2. red
3. green, yellow
4. blue
5. brown
6. purple, pink, orange, gray

Additionally, people worldwide seem to agree quite well on the typical values of each of these color terms. This theory is a fascinating one and forms a good basis for choosing basic colors for this swatch grid.

This widget's colors have been arranged largely according to the color wheel of the perceptually uniform color space. We start with the saturated basic colors: red, orange, yellow, green, blue, and purple in order of their hue angles. Next, we have pink and brown, which have roughly the same hue as red or orange but are less saturated. These are simply the less chromatic parts of this hue but are nevertheless perceived by humans as independent colors. For each of these basic colors, there are five variants in the order of tint, pure color, and shade. Following the saturated colors and eventually the less saturated ones, the gray axis comes in last place.

What exact colors are used? What exactly is a typical “red” or a “green”? Doesn’t every human have a slightly different feeling what a “typical” red or a “typical” blue is? We need a focal color, which is, according to Oxford Reference:

“A colour that is a prototypical instance of a particular colour name, such as a shade of red that a majority of viewers consider to be the best example of a red colour.”

The World Color Survey (WCS) is a significant study about focal colors of speakers of different languages across the world. The data from this survey is available online, and while it does not provide direct values for focal colors, various studies have used this data to determine focal colors for some basic color terms and a naming centroid for others.

The table below shows the WCS grid coordinates for the basic color terms along with the corresponding Cielab values for the focal color (where available) or the naming centroid (where focal color data is unavailable).

Basic color term	WCS grid coordinates	Cielab³ L	Cielab³ a	Cielab³ b
white¹	A0	96.00	-0.06	0.06
black¹	J0	15.60	-0.02	0.02
red¹	G1	41.22	61.40	17.92
yellow¹	C9	81.35	7.28	109.12
green¹	F17	51.57	-63.28	28.95
blue¹	F29	51.57	-3.41	-48.08
brown³	G7	41.22	17.04	45.95
purple³	G34	41.22	33.08	-30.50
pink³	E1	61.70	49.42	18.23
orange³	E6	61.70	29.38	64.40
gray	not available

¹ Focal color as proposed by Focal colors are universal after all.

² Raw estimation of the naming centroid based on Fig. 4 of this document. (Fig. 5 would be the better choice, as it gives the focal color instead of the naming centroid, but unfortunately contains only red, yellow, green and blue, for which we have yet direct data.)

³ Lookup table providing Lab values for WCS grid coordinates and the corresponding explanation.

From this data, the colors in our swatch grid have been derived as follows:

• The gray axis has been defined manually, ignoring the WCS data. Chroma is 0. The lightness is 100% for white, 0% for black, and 75%, 50%, and 25% for the intermediate grays.
• The other columns for chromatic colors use the WCS data for the swatch in the middle. Tints and shades are calculated by adding or reducing chroma and lightness within the Oklab color space. If the resulting color falls outside the color space, a nearby in-gamut color is chosen instead.

Parameters

colorSpace

The color space in which the return value is calculated.

Returns

Swatch grid derived from the basic colors. Provides as a list of basic colors (in this order: red, orange, yellow, green, blue, purple, pink, brown, gray axis). Each basic color is a list of 5 swatches (starting with the lightest and finishing with the darkest: 2 tints, the tone itself, 2 shades).

Note

The RGB value is rounded to full integers in the range [0, 255].

Definition at line 465 of file helper.cpp.

Variable Documentation

gamutPrecisionCielab

qreal PerceptualColor::gamutPrecisionCielab = 0.001

constexpr

Definition at line 26 of file helperconstants.h.

gamutPrecisionOklab

qreal PerceptualColor::gamutPrecisionOklab = gamutPrecisionCielab / 100

constexpr

Definition at line 35 of file helperconstants.h.

overlap

int PerceptualColor::overlap = 2

constexpr

Definition at line 48 of file helperconstants.h.

pageStepAlpha

qreal PerceptualColor::pageStepAlpha = 10 * singleStepAlpha

constexpr

Definition at line 153 of file helperconstants.h.

pageStepChroma

int PerceptualColor::pageStepChroma = 10 * singleStepChroma

constexpr

Definition at line 169 of file helperconstants.h.

pageStepHue

int PerceptualColor::pageStepHue = 10 * singleStepHue

constexpr

Definition at line 185 of file helperconstants.h.

pageStepLightness

int PerceptualColor::pageStepLightness = 10 * singleStepLightness

constexpr

Definition at line 201 of file helperconstants.h.

pi

auto PerceptualColor::pi = M_PI

constexpr

Definition at line 31 of file helperposixmath.h.

richTextMarker

const QString PerceptualColor::richTextMarker = QStringLiteral(u"<a/>")

inline

Definition at line 221 of file helperconstants.h.

scaleFromMinumumSizeHintToSizeHint

qreal PerceptualColor::scaleFromMinumumSizeHintToSizeHint = 1.2

constexpr

Definition at line 59 of file helperconstants.h.

singleStepAlpha

qreal PerceptualColor::singleStepAlpha = 0.01

constexpr

Definition at line 73 of file helperconstants.h.

singleStepChroma

int PerceptualColor::singleStepChroma = 1

constexpr

Definition at line 87 of file helperconstants.h.

singleStepHue

int PerceptualColor::singleStepHue = 360 / 100

constexpr

Definition at line 110 of file helperconstants.h.

singleStepLightness

int PerceptualColor::singleStepLightness = 1

constexpr

Definition at line 124 of file helperconstants.h.

singleStepOklabc

double PerceptualColor::singleStepOklabc = 0.01

constexpr

Definition at line 137 of file helperconstants.h.

whitePointD65TwoDegree

cmsCIEXYZ PerceptualColor::whitePointD65TwoDegree {0.95047, 1.00000, 1.08883}

constexpr

Definition at line 161 of file helperconversion.h.