The QColor class provides colors based on RGB, HSV or CMYK values. More...

Public Types
enum	Spec

Public Methods
	QColor ()

	QColor (const char *name)

	QColor (const QColor &other)

	QColor (const QString &name)

	QColor (int r, int g, int b, int a=255)

	QColor (QColor &&other)

	QColor (QRgb rgb)

	QColor (QRgba64 rgba64)

	QColor (Qt::GlobalColor color)

	QColor (Spec spec)

int	alpha () const

qreal	alphaF () const

int	black () const

qreal	blackF () const

int	blue () const

qreal	blueF () const

QColor	convertTo (Spec colorSpec) const

int	cyan () const

qreal	cyanF () const

QColor	dark (int factor=200) const

QColor	darker (int factor=200) const

void	getCmyk (int c, int m, int y, int k, int *a=nullptr)

void	getCmykF (qreal c, qreal m, qreal y, qreal k, qreal *a=nullptr)

void	getHsl (int h, int s, int l, int a=nullptr) const

void	getHslF (qreal h, qreal s, qreal l, qreal a=nullptr) const

void	getHsv (int h, int s, int v, int a=nullptr) const

void	getHsvF (qreal h, qreal s, qreal v, qreal a=nullptr) const

void	getRgb (int r, int g, int b, int a=nullptr) const

void	getRgbF (qreal r, qreal g, qreal b, qreal a=nullptr) const

int	green () const

qreal	greenF () const

int	hslHue () const

qreal	hslHueF () const

int	hslSaturation () const

qreal	hslSaturationF () const

int	hsvHue () const

qreal	hsvHueF () const

int	hsvSaturation () const

qreal	hsvSaturationF () const

int	hue () const

qreal	hueF () const

bool	isValid () const

QColor	light (int factor=150) const

QColor	lighter (int factor=150) const

int	lightness () const

qreal	lightnessF () const

int	magenta () const

qreal	magentaF () const

QString	name (NameFormat format=HexRgb) const

	operator QVariant () const

bool	operator!= (const QColor &color) const

QColor &	operator= (Qt::GlobalColor color)

bool	operator== (const QColor &color) const

int	red () const

qreal	redF () const

QRgb	rgb () const

QRgb	rgba () const

QRgba64	rgba64 () const

int	saturation () const

qreal	saturationF () const

void	setAlpha (int alpha)

void	setAlphaF (qreal alpha)

void	setBlue (int blue)

void	setBlueF (qreal blue)

void	setCmyk (int c, int m, int y, int k, int a=255)

void	setCmykF (qreal c, qreal m, qreal y, qreal k, qreal a=1.0)

void	setGreen (int green)

void	setGreenF (qreal green)

void	setHsl (int h, int s, int l, int a=255)

void	setHslF (qreal h, qreal s, qreal l, qreal a=1.0)

void	setHsv (int h, int s, int v, int a=255)

void	setHsvF (qreal h, qreal s, qreal v, qreal a=1.0)

void	setNamedColor (const QString &name)

void	setRed (int red)

void	setRedF (qreal red)

void	setRgb (int r, int g, int b, int a=255)

void	setRgb (QRgb rgb)

void	setRgba (QRgb rgba)

void	setRgba64 (QRgba64 rgba)

void	setRgbF (qreal r, qreal g, qreal b, qreal a=1.0)

Spec	spec () const

QColor	toCmyk () const

QColor	toHsl () const

QColor	toHsv () const

QColor	toRgb () const

int	value () const

qreal	valueF () const

int	yellow () const

qreal	yellowF () const

Static Public Methods
static QStringList	colorNames ()

static QColor	fromCmyk (int c, int m, int y, int k, int a=255)

static QColor	fromCmykF (qreal c, qreal m, qreal y, qreal k, qreal a=1.0)

static QColor	fromHsl (int h, int s, int l, int a=255)

static QColor	fromHslF (qreal h, qreal s, qreal l, qreal a=1.0)

static QColor	fromHsv (int h, int s, int v, int a=255)

static QColor	fromHsvF (qreal h, qreal s, qreal v, qreal a=1.0)

static QColor	fromRgb (int r, int g, int b, int a=255)

static QColor	fromRgb (QRgb rgb)

static QColor	fromRgba (QRgb rgba)

static QColor	fromRgba64 (QRgba64 rgba)

static QColor	fromRgba64 (ushort r, ushort g, ushort b, ushort a=USHRT_MAX)

static QColor	fromRgbF (qreal r, qreal g, qreal b, qreal a=1.0)

static bool	isValidColor (const QString &name)

Friends
QDataStream &	operator<< (QDataStream &stream, const QColor &color)

QDataStream &	operator>> (QDataStream &stream, QColor &color)

class	QColormap

Related Functions
These are not member functions
int	qAlpha (QRgb rgba)

int	qBlue (QRgb rgb)

int	qGray (int r, int g, int b)

int	qGray (QRgb rgb)

int	qGreen (QRgb rgb)

int	qRed (QRgb rgb)

typedef	QRgb

QRgb	qRgb (int r, int g, int b)

QRgb	qRgba (int r, int g, int b, int a)

Detailed Description

The QColor class provides colors based on RGB, HSV or CMYK values.

A color is normally specified in terms of RGB (red, green, and blue) components, but it is also possible to specify it in terms of HSV (hue, saturation, and value) and CMYK (cyan, magenta, yellow and black) components. In addition a color can be specified using a color name. The color name can be any of the SVG 1.0 color names.

RGB	HSV	CMYK

The QColor constructor creates the color based on RGB values. To create a QColor based on either HSV or CMYK values, use the toHsv() and toCmyk() methods respectively. These functions return a copy of the color using the desired format. In addition the static fromRgb(), fromHsv() and fromCmyk() functions create colors from the specified values. Alternatively, a color can be converted to any of the three formats using the convertTo() function (returning a copy of the color in the desired format), or any of the setRgb(), setHsv() and setCmyk() functions altering this color's format. The spec() function tells how the color was specified.

A color can be set by passing an RGB string (such as "#112233"), or a color name (such as "blue"), to the setNamedColor() function. The color names are taken from the SVG 1.0 color names. The name() function returns the name of the color in the format "#RRGGBB". Colors can also be set using setRgb(), setHsv() and setCmyk(). To get a lighter or darker color use the lighter() and darker() functions respectively.

The isValid() function indicates whether a QColor is legal at all. For example, a RGB color with RGB values out of range is illegal. For performance reasons, QColor mostly disregards illegal colors, and for that reason, the result of using an invalid color is undefined.

The color components can be retrieved individually, e.g with red(), hue() and cyan(). The values of the color components can also be retrieved in one go using the getRgb(), getHsv() and getCmyk() functions. Using the RGB color model, the color components can in addition be accessed with rgb().

QRgb is a typedef for an unsigned int representing the RGB value triplet (r, g, b). It can hold a value for the alpha channel. For more information refer to the Alpha-Blended Drawing section.

The qRed(), qBlue() and qGreen() functions return the respective component of the given QRgb value, while the qRgb() and qRgba() functions create and return the QRgb triplet based on the given component values. Finally, the qAlpha() function returns the alpha component of the provided QRgb, and the qGray() function calculates and return a gray value based on the given value.

QColor is platform and device independent. The QColormap class maps the color to the hardware.

For more information about painting refer to the Paint System documentation.

Integer versus Floating Point Precision

QColor supports floating point precision and provides floating point versions of color methods like, getRgbF(), hueF(), and fromCmykF(). Since the components are stored using 16-bit integers there might be minor deviations between the values set using setRgbF() and the values returned by the getRgbF() due to rounding.

While the integer based methods take values in the range 0-255 (except hue() which must have values within the range 0-359), the floating point functions accept values in the range 0.0 - 1.0.

Alpha-Blended Drawing

QColor also support alpha-blended outlining and filling. The alpha channel of a color specifies the transparency effect. The value of 0 represents a fully transparent color while 255 represents a fully opaque color.

// Specify semi-transparent red
painter.setBrush(QColor(255, 0, 0, 127));
painter.drawRect(0, 0, width()/2, height());
 
// Specify semi-transparent blue
painter.setBrush(QColor(0, 0, 255, 127));
painter.drawRect(0, 0, width(), height()/2);

The code above produces the following output:

Alpha-blended drawing is supported on Windows, Mac OS X, and on X11 systems that have the X Render extension installed.

The alpha channel of a color can be retrieved and set using the alpha() and setAlpha() methods if its value is an integer, and alphaF() and setAlphaF() if its value is qreal (double). By default, the alpha-channel is set to 255 (opaque). To retrieve and set all the RGB color components (including the alpha-channel) in one go, use the rgba() and setRgba() methods.

Predefined Colors

There are 20 predefined QColors described by the Qt::GlobalColor enum, including black, white, primary and secondary colors, darker versions of these colors and three shades of gray. QColor also recognizes a variety of color names; the static colorNames() method returns a QStringList color names that QColor knows about.

Additionally, the Qt::color0, Qt::color1 and Qt::transparent colors are used for special purposes.

Qt::color0 (zero pixel value) and Qt::color1 (non-zero pixel value) are special colors for drawing in QBitmaps. Painting with Qt::color0 sets the bitmap bits to 0 (transparent; i.e., background), and painting with Qt::color1 sets the bits to 1 (opaque; i.e., foreground).

Qt::transparent is used to indicate a transparent pixel. When painting with this value, a pixel value will be used that is appropriate for the underlying pixel format in use.

HSV Color Model

The RGB model is hardware-oriented. Its representation is close to what most monitors show. In contrast, HSV represents color in a way more suited to the human perception of color. For example, the relationships "stronger than", "darker than", and "the opposite of" are easily expressed in HSV but are much harder to express in RGB.

HSV, like RGB, has three components:

H, for hue, is in the range 0 to 359 if the color is chromatic (not gray), or meaningless if it is gray. It represents degrees on the color wheel familiar to most people. Red is 0 (degrees), green is 120, and blue is 240.
S, for saturation, is in the range 0 to 255, and the bigger it is, the stronger the color is. Grayish colors have saturation near 0; very strong colors have saturation near 255.
V, for value, is in the range 0 to 255 and represents lightness or brightness of the color. 0 is black; 255 is as far from black as possible.

Here are some examples: pure red is H=0, S=255, V=255. A dark red, moving slightly towards the magenta, could be H=350 (equivalent to -10), S=255, V=180 where as a grayish light red could have H about 0 (say 350-359 or 0-10), S about 50-100, and S=255.

For achromatic color the hue value returned is -1. If you pass a hue value that is too large, it will reset into range. Hue 360 or 720 is treated as 0, hue 540 is treated as 180.

In addition to the standard HSV model there is also an alpha-channel feature Alpha-Blended Drawing.

HSL Color Model

HSL is similar to HSV. Instead of value parameter from HSV, HSL has the lightness parameter. The lightness parameter goes from black to color and from color to white. If you go outside at the night its black or dark gray. At day its colorful but if you look in a really strong light a things they are going to white and wash out.

CMYK Color Model

While the RGB and HSV color models are used for display on computer monitors, the CMYK model is used in the four-color printing process of printing presses and some hard-copy devices.

CMYK has four components, all in the range 0-255: cyan (C), magenta (M), yellow (Y) and black (K). Cyan, magenta and yellow are called subtractive colors; the CMYK color model creates color by starting with a white surface and then subtracting color by applying the appropriate components. While combining cyan, magenta and yellow gives the color black, subtracting one or more will yield any other color. When combined in various percentages, these three colors can create the entire spectrum of colors.

Mixing 100 percent of cyan, magenta and yellow does produce black, but the result is unsatisfactory since it wastes ink, increases drying time, and gives a muddy color when printing. For that reason, black is added in professional printing to provide a solid black tone; hence the term 'four color process'.

In addition to the standard CMYK model there is also an alpha-channel to feature Alpha-Blended Drawing.

See also: QPalette, QBrush, QApplication::setColorSpec()

Member Enumeration Documentation

enum QColor::Spec

The type of color specified, either RGB, HSV, CMYK or HSL.

Constant	Value
`QColor::Rgb`	`1`
`QColor::Hsv`	`2`
`QColor::Cmyk`	`3`
`QColor::Hsl`	`4`
`QColor::Invalid`	`0`

See also: spec(), convertTo()

Constructor & Destructor Documentation

QColor::QColor ( const QColor & other )

Copy constructs a new QColor from other.

See also: isValid()

QColor::QColor ( QColor && other )

Move constructs a new QColor other.

See also: isValid()

QColor::QColor ( )

inline

Constructs an invalid color with the RGB value (0, 0, 0). An invalid color is a color that is not properly set up for the underlying window system.

The alpha value of an invalid color is unspecified.

See also: isValid()

QColor::QColor ( Qt::GlobalColor color )

Constructs a new QColor with a color value of color.

See also: isValid(), Predefined Colors

QColor::QColor	(	int	r,
		int	g,
		int	b,
		int	a = `255`
	)

inline

Constructs a color with the RGB value r, g, b, and the alpha channel value of a. The color is invalid if any of the arguments are invalid.

See also: setRgba(), isValid()

QColor::QColor ( QRgb rgb )

Constructs a color with the value rgb. The alpha component is ignored and set to solid.

See also: fromRgb(), isValid()

QColor::QColor ( QRgba64 rgba64 )

Constructs a color with the given rgba64 value.

QColor::QColor ( const QString & name )

inline

Constructs a named color in the same way as setNamedColor() using the given name. The color is invalid if the name can not be parsed.

See also: setNamedColor(), name(), isValid()

QColor::QColor ( const char * name )

inline

Constructs a named color in the same way as setNamedColor() using the given name. The color is invalid if name can not be parsed.

See also: setNamedColor(), name(), isValid()

QColor::QColor ( Spec spec )

Constructs a color with the given spec enum value.

Method Documentation

int QColor::alpha ( ) const

Returns the alpha color component of this color.

See also: setAlpha(), alphaF(), Alpha-Blended Drawing

qreal QColor::alphaF ( ) const

Returns the alpha color component of this color.

See also: setAlphaF(), alpha(), Alpha-Blended Drawing

int QColor::black ( ) const

Returns the black color component of this color.

See also: blackF(), getCmyk(), CMYK Color Model

qreal QColor::blackF ( ) const

Returns the black color component of this color.

See also: black(), getCmykF(), CMYK Color Model

int QColor::blue ( ) const

Returns the blue color component of this color.

See also: setBlue(), blueF(), getRgb()

qreal QColor::blueF ( ) const

Returns the blue color component of this color.

See also: setBlueF(), blue(), getRgbF()

QStringList QColor::colorNames ( )

static

Returns a QStringList containing the color names CopperSpice knows about.

See also: Predefined Colors

QColor QColor::convertTo ( Spec colorSpec ) const

Creates a copy of this color in the format specified by colorSpec.

See also: spec(), toCmyk(), toHsv(), toRgb(), isValid()

int QColor::cyan ( ) const

Returns the cyan color component of this color.

See also: cyanF(), getCmyk(), CMYK Color Model

qreal QColor::cyanF ( ) const

Returns the cyan color component of this color.

See also: cyan(), getCmykF(), CMYK Color Model

QColor QColor::dark ( int factor = 200 ) const

deprecated

Deprecated:: Use darker(factor) instead.

QColor QColor::darker ( int factor = 200 ) const

inline

Returns a darker (or lighter) color, but does not change this object.

If the factor is greater than 100, this methods returns a darker color. Setting factor to 300 returns a color that has one-third the brightness. If the factor is less than 100, the return color is lighter, but we recommend using the lighter() method for this purpose. If the factor is 0 or negative, the return value is unspecified.

The method converts the current RGB color to HSV, divides the value (V) component by factor and converts the color back to RGB.

See also: lighter(), isValid()

QColor QColor::fromCmyk	(	int	c,
		int	m,
		int	y,
		int	k,
		int	a = `255`
	)

static

Returns a QColor constructed from the given CMYK color values: c (cyan), m (magenta), y (yellow), k (black), and a (alpha channel). All the values must be in the range 0-255.

See also: toCmyk(), fromCmykF(), isValid(), CMYK Color Model

QColor QColor::fromCmykF	(	qreal	c,
		qreal	m,
		qreal	y,
		qreal	k,
		qreal	a = `1.0`
	)

static

Returns a QColor constructed from the given CMYK color values: c (cyan), m (magenta), y (yellow), k (black), and a (alpha channel).

All the values must be in the range 0.0 to 1.0.

See also: toCmyk(), fromCmyk(), isValid(), CMYK Color Model

QColor QColor::fromHsl	(	int	h,
		int	s,
		int	l,
		int	a = `255`
	)

static

Returns a QColor constructed from the HSV color values, h (hue), s (saturation), l (lightness), and a (alpha channel).

The value of s, l, and a must all be in the range 0-255; the value of h must be in the range 0-359.

See also: toHsl(), fromHslF(), isValid()

QColor QColor::fromHslF	(	qreal	h,
		qreal	s,
		qreal	l,
		qreal	a = `1.0`
	)

static

Returns a QColor constructed from the HSV color values, h (hue), s (saturation), l (lightness), and a (alpha channel). All values must be in the range 0.0 to 1.0.

See also: toHsl(), fromHsl(), isValid()

QColor QColor::fromHsv	(	int	h,
		int	s,
		int	v,
		int	a = `255`
	)

static

Returns a QColor constructed from the HSV color values, h (hue), s (saturation), v (value), and a (alpha channel).

The values of s, v, and a must all be in the range 0-255; the value of h must be in the range 0-359.

See also: toHsv(), fromHsvF(), isValid(), HSV Color Model

QColor QColor::fromHsvF	(	qreal	h,
		qreal	s,
		qreal	v,
		qreal	a = `1.0`
	)

static

Returns a QColor constructed from the HSV color values, h (hue), s (saturation), v (value), and a (alpha channel). All the values must be in the range 0.0 to 1.0.

See also: toHsv(), fromHsv(), isValid(), HSV Color Model

QColor QColor::fromRgb	(	int	r,
		int	g,
		int	b,
		int	a = `255`
	)

static

Static method that returns a QColor constructed from the RGB color values, r (red), g (green), b (blue), and a (alpha channel). All values must be in the range 0-255.

See also: toRgb(), fromRgbF(), isValid()

QColor QColor::fromRgb ( QRgb rgb )

static

Static method that returns a QColor constructed from the given QRgb value rgb.

The alpha component of rgb is ignored (i.e. it is automatically set to 255), use the fromRgba() method to include the alpha channel specified by the given QRgb value.

See also: fromRgba(), fromRgbF(), toRgb(), isValid()

QColor QColor::fromRgba ( QRgb rgba )

static

Returns a QColor constructed from the given QRgb value rgba. Unlike the fromRgb() method, the alpha channel specified by the given QRgb value is included.

See also: fromRgb(), isValid()

QColor QColor::fromRgba64 ( QRgba64 rgba )

static

Static method that returns a QColor constructed from the given QRgba64 value rgba64.

See also: fromRgb(), fromRgbF(), toRgb(), isValid()

QColor QColor::fromRgba64	(	ushort	r,
		ushort	g,
		ushort	b,
		ushort	a = `USHRT_MAX`
	)

static

Returns a QColor constructed from the RGBA64 color values, r (red), g (green), b (blue), and a (alpha channel).

See also: fromRgb(), fromRgbF(), toRgb(), isValid()

QColor QColor::fromRgbF	(	qreal	r,
		qreal	g,
		qreal	b,
		qreal	a = `1.0`
	)

static

Static method that returns a QColor constructed from the RGB color values, r (red), g (green), b (blue), and a (alpha channel). All values must be in the range 0.0 to 1.0.

See also: fromRgb(), toRgb(), isValid()

void QColor::getCmyk	(	int *	c,
		int *	m,
		int *	y,
		int *	k,
		int *	a = `nullptr`
	)

Sets the contents pointed to by c, m, y, k, and a, to the cyan, magenta, yellow, black, and alpha channel components of the color's CMYK value.

These components can be retrieved individually using the cyan(), magenta(), yellow(), black() and alpha() methods.

See also: setCmyk(), CMYK Color Model

void QColor::getCmykF	(	qreal *	c,
		qreal *	m,
		qreal *	y,
		qreal *	k,
		qreal *	a = `nullptr`
	)

Sets the contents pointed to by c, m, y, k, and a, to the cyan, magenta, yellow, black, and alpha channel components of the color's CMYK value.

These components can be retrieved individually using the cyanF(), magentaF(), yellowF(), blackF() and alphaF() methods.

See also: setCmykF(), CMYK Color Model

void QColor::getHsl	(	int *	h,
		int *	s,
		int *	l,
		int *	a = `nullptr`
	)		const

Sets the contents pointed to by h, s, l, and a, to the hue, saturation, lightness, and alpha channel components of the color's HSL value.

These components can be retrieved individually using the hslHue(), hslSaturation(), lightness() and alpha() methods.

See also: setHsl()

void QColor::getHslF	(	qreal *	h,
		qreal *	s,
		qreal *	l,
		qreal *	a = `nullptr`
	)		const

Sets the contents pointed to by h, s, l, and a, to the hue, saturation, lightness, and alpha channel components of the color's HSL value. These components can be retrieved individually using the hslHueF(), hslSaturationF(), lightnessF() and alphaF() methods.

See also: setHsl()

void QColor::getHsv	(	int *	h,
		int *	s,
		int *	v,
		int *	a = `nullptr`
	)		const

Sets the contents pointed to by h, s, v, and a, to the hue, saturation, value, and alpha channel components of the color's HSV value. These components can be retrieved individually using the hue(), saturation(), value() and alpha() methods.

See also: setHsv(), HSV Color Model

void QColor::getHsvF	(	qreal *	h,
		qreal *	s,
		qreal *	v,
		qreal *	a = `nullptr`
	)		const

Sets the contents pointed to by h, s, v, and a, to the hue, saturation, value, and alpha channel (transparency) components of the color's HSV value. These components can be retrieved individually using the hueF(), saturationF(), valueF() and alphaF() methods.

See also: setHsv(), HSV Color Model

void QColor::getRgb	(	int *	r,
		int *	g,
		int *	b,
		int *	a = `nullptr`
	)		const

Sets the contents pointed to by r, g, b, and a, to the red, green, blue, and alpha channel components of the color's RGB value. These components can be retrieved individually using the red(), green(), blue() and alpha() methods.

See also: rgb(), setRgb()

void QColor::getRgbF	(	qreal *	r,
		qreal *	g,
		qreal *	b,
		qreal *	a = `nullptr`
	)		const

Sets the contents pointed to by r, g, b, and a, to the red, green, blue, and alpha channel components of the color's RGB value. These components can be retrieved individually using the redF(), greenF(), blueF() and alphaF() methods.

See also: rgb(), setRgb()

int QColor::green ( ) const

Returns the green color component of this color.

See also: setGreen(), greenF(), getRgb()

qreal QColor::greenF ( ) const

Returns the green color component of this color.

See also: setGreenF(), green(), getRgbF()

int QColor::hslHue ( ) const

Returns the hue color component of this color.

See also: getHslF(), getHsl()

qreal QColor::hslHueF ( ) const

Returns the hue color component of this color.

See also: hue(), getHslF()

int QColor::hslSaturation ( ) const

Returns the saturation color component of this color.

See also: saturationF(), getHsv(), HSV Color Model

qreal QColor::hslSaturationF ( ) const

Returns the saturation color component of this color.

See also: saturationF(), getHslF()

int QColor::hsvHue ( ) const

Returns the hue color component of this color.

See also: hueF(), getHsv(), HSV Color Model

qreal QColor::hsvHueF ( ) const

Returns the hue color component of this color.

See also: hue(), getHsvF(), HSV Color Model

int QColor::hsvSaturation ( ) const

Returns the saturation color component of this color.

See also: saturationF(), getHsv(), HSV Color Model

qreal QColor::hsvSaturationF ( ) const

Returns the saturation color component of this color.

See also: saturation(), getHsvF(), HSV Color Model

int QColor::hue ( ) const

Returns the hue color component of this color.

The color is implicitly converted to HSV.

See also: hsvHue(), hueF(), getHsv(), HSV Color Model

qreal QColor::hueF ( ) const

Returns the hue color component of this color.

The color is implicitly converted to HSV.

See also: hsvHueF(), hue(), getHsvF(), HSV Color Model

bool QColor::isValid ( ) const

inline

Returns true if the color is valid, otherwise returns false.

bool QColor::isValidColor ( const QString & name )

static

Returns true if the name is a valid color name and can be used to construct a valid QColor object, otherwise returns false.

It uses the same algorithm used in setNamedColor().

See also: setNamedColor()

QColor QColor::light ( int factor = 150 ) const

deprecated

Deprecated:: Use lighter(factor) instead.

QColor QColor::lighter ( int factor = 150 ) const

inline

Returns a lighter (or darker) color, but does not change this object.

If the factor is greater than 100, this methods returns a lighter color. Setting factor to 150 returns a color that is 50% brighter. If the factor is less than 100, the return color is darker, but we recommend using the darker() method for this purpose. If the factor is 0 or negative, the return value is unspecified.

The method converts the current RGB color to HSV, multiplies the value (V) component by factor and converts the color back to RGB.

See also: darker(), isValid()

int QColor::lightness ( ) const

Returns the lightness color component of this color.

See also: lightnessF(), getHsl()

qreal QColor::lightnessF ( ) const

Returns the lightness color component of this color.

See also: value(), getHslF()

int QColor::magenta ( ) const

Returns the magenta color component of this color.

See also: magentaF(), getCmyk(), CMYK Color Model

qreal QColor::magentaF ( ) const

Returns the magenta color component of this color.

See also: magenta(), getCmykF(), CMYK Color Model

QString QColor::name ( NameFormat format = HexRgb ) const

Returns the name of the color in the specified format. The default format is "\#RRGGBB". For example, a "\#" character followed by three two-digit hexadecimal numbers.

See also: setNamedColor()

QColor::operator QVariant ( ) const

Returns the color as a QVariant

bool QColor::operator!= ( const QColor & color ) const

Returns true if this color has a different RGB and alpha values from color, otherwise returns false.

QColor & QColor::operator= ( Qt::GlobalColor color )

Assigns the given color to this QColor and returns a reference to this object.

bool QColor::operator== ( const QColor & color ) const

Returns true if this QColor has the same RGB and alpha values as the given color, otherwise returns false.

int QColor::red ( ) const

Returns the red color component of this color.

See also: setRed(), redF(), getRgb()

qreal QColor::redF ( ) const

Returns the red color component of this color.

See also: setRedF(), red(), getRgbF()

QRgb QColor::rgb ( ) const

Returns the RGB value of the color. The alpha value is opaque.

See also: setRgb(), getRgb(), rgba()

QRgb QColor::rgba ( ) const

Returns the RGB value of the color, including its alpha. For an invalid color, the alpha value of the returned color is unspecified.

See also: setRgba(), rgb()

QRgba64 QColor::rgba64 ( ) const

Returns the RGB64 value of the color, including its alpha. For an invalid color, the alpha value of the returned color is unspecified.

See also: setRgba64(), rgba(), rgb()

int QColor::saturation ( ) const

Returns the saturation color component of this color.

The color is implicitly converted to HSV.

See also: hsvSaturation(), saturationF(), getHsv(), HSV Color Model

qreal QColor::saturationF ( ) const

Returns the saturation color component of this color.

The color is implicitly converted to HSV.

See also: hsvSaturationF(), saturation(), getHsvF(), HSV Color Model

void QColor::setAlpha ( int alpha )

Sets the alpha of this color to alpha. Integer alpha is specified in the range 0-255.

See also: alpha(), alphaF(), Alpha-Blended Drawing

void QColor::setAlphaF ( qreal alpha )

Sets the alpha of this color to alpha. qreal alpha is specified in the range 0.0 to 1.0.

See also: alphaF(), alpha(), Alpha-Blended Drawing

void QColor::setBlue ( int blue )

Sets the blue color component of this color to blue. Integer components are specified in the range 0-255.

See also: blue(), blueF(), setRgb()

void QColor::setBlueF ( qreal blue )

Sets the blue color component of this color to blue. Float components are specified in the range 0.0 to 1.0.

See also: blueF(), blue(), setRgbF()

void QColor::setCmyk	(	int	c,
		int	m,
		int	y,
		int	k,
		int	a = `255`
	)

Sets the color to CMYK values, c (cyan), m (magenta), y (yellow), k (black), and a (alpha channel). All the values must be in the range 0-255.

See also: getCmyk(), setCmykF(), CMYK Color Model

void QColor::setCmykF	(	qreal	c,
		qreal	m,
		qreal	y,
		qreal	k,
		qreal	a = `1.0`
	)

Sets the color to CMYK values, c (cyan), m (magenta), y (yellow), k (black), and a (alpha channel). All values must be in the range 0.0 to 1.0.

See also: getCmykF(), setCmyk(), CMYK Color Model

void QColor::setGreen ( int green )

Sets the green color component of this color to green. Integer components are specified in the range 0-255.

See also: green(), greenF(), setRgb()

void QColor::setGreenF ( qreal green )

Sets the green color component of this color to green. Float components are specified in the range 0.0 to 1.0.

See also: greenF(), green(), setRgbF()

void QColor::setHsl	(	int	h,
		int	s,
		int	l,
		int	a = `255`
	)

Sets a HSL color value. The values for h, s, l, and a are the hue, saturation, lightness, and alpha component of the HSL color. The saturation, value, and alpha channel values must be in the range 0-255, and the hue value must be greater than -1.

See also: getHsl(), setHslF()

void QColor::setHslF	(	qreal	h,
		qreal	s,
		qreal	l,
		qreal	a = `1.0`
	)

Sets a HSL color lightness. The values for h, s, l, and a are the hue, saturation, lightness, and alpha component of the HSL color. All the values must be in the range 0.0 to 1.0.

See also: getHslF(), setHsl()

void QColor::setHsv	(	int	h,
		int	s,
		int	v,
		int	a = `255`
	)

Sets a HSV color value. The values for h, s, v, and a are the hue, saturation, value, and alpha component of the HSL color. The saturation, value, and alpha channel values must be in the range 0-255, and the hue value must be greater than -1.

See also: getHsv(), setHsvF(), HSV Color Model

void QColor::setHsvF	(	qreal	h,
		qreal	s,
		qreal	v,
		qreal	a = `1.0`
	)

Sets a HSV color value. The values for h, s, v, and a are the hue, saturation, value, and alpha component of the HSL color. All the values must be in the range 0.0 to 1.0.

See also: getHsvF(), setHsv(), HSV Color Model.

void QColor::setNamedColor ( const QString & name )

Sets the RGB value of this QColor to name, which may be in one of the following formats. The color is invalid if name can not be parsed.

#RGB (each of R, G, and B is a single hex digit)
#RRGGBB
#RRRGGGBBB
#RRRRGGGGBBBB

A name from the list of colors defined in the list of SVG color keyword names provided by the World Wide Web Consortium. For example, "steelblue" or "gainsboro". These color names work on all platforms.
Color names are not the same as those defined by the Qt::GlobalColor enums. For example, "green" and Qt::green does not refer to the same color.
"transparent" which represents the absence of a color.

See also: QColor(), name(), isValid()

void QColor::setRed ( int red )

Sets the red color component of this color to red. Integer components are specified in the range 0-255.

See also: red(), redF(), setRgb()

void QColor::setRedF ( qreal red )

Sets the red color component of this color to red. Float components are specified in the range 0.0 to 1.0.

See also: redF(), red(), setRgbF()

void QColor::setRgb	(	int	r,
		int	g,
		int	b,
		int	a = `255`
	)

Sets the RGB value to r, g, b and the alpha value to a. All the values must be in the range 0-255.

See also: rgb(), getRgb(), setRgbF()

void QColor::setRgb ( QRgb rgb )

Sets the RGB value to rgb. The alpha value is set to opaque.

void QColor::setRgba ( QRgb rgba )

Sets the RGB value to rgba, including its alpha.

See also: rgba(), rgb()

void QColor::setRgba64 ( QRgba64 rgba )

Sets the RGB value to rgba, including its alpha.

See also: rgba(), rgb(), setRgba64()

void QColor::setRgbF	(	qreal	r,
		qreal	g,
		qreal	b,
		qreal	a = `1.0`
	)

Sets the color channels of this color to r (red), g (green), b (blue) and a (alpha, transparency).

All values must be in the range 0.0 to 1.0.

See also: rgb(), getRgbF(), setRgb()

Spec QColor::spec ( ) const

inline

Returns how the color was specified.

See also: Spec, convertTo()

QColor QColor::toCmyk ( ) const

Creates and returns a CMYK QColor based on this color.

See also: fromCmyk(), convertTo(), isValid(), CMYK Color Model

QColor QColor::toHsl ( ) const

Creates and returns an HSL QColor based on this color.

See also: fromHsl(), convertTo(), isValid()

QColor QColor::toHsv ( ) const

Creates and returns an HSV QColor based on this color.

See also: fromHsv(), convertTo(), isValid(), HSV Color Model

QColor QColor::toRgb ( ) const

Create and returns an RGB QColor based on this color.

See also: fromRgb(), convertTo(), isValid()

int QColor::value ( ) const

Returns the value color component of this color.

See also: valueF(), getHsv(), HSV Color Model

qreal QColor::valueF ( ) const

Returns the value color component of this color.

See also: value(), getHsvF(), HSV Color Model

int QColor::yellow ( ) const

Returns the yellow color component of this color.

See also: yellowF(), getCmyk(), CMYK Color Model

qreal QColor::yellowF ( ) const

Returns the yellow color component of this color.

See also: yellow(), getCmykF(), CMYK Color Model

Friends And Related Function Documentation

QDataStream & operator<<	(	QDataStream &	stream,
		const QColor &	color
	)

friend

Writes the color to the stream and returns a reference to the stream.

Refer to Serializing Data Types for additional information.

QDataStream & operator>>	(	QDataStream &	stream,
		QColor &	color
	)

friend

Reads the color from the stream and returns a reference to the stream.

Refer to Serializing Data Types for additional information.

int qAlpha ( QRgb rgba )

See also: qRgb(), QColor::alpha()

int qBlue ( QRgb rgb )

See also: qRgb(), QColor::blue()

int qGray	(	int	r,
		int	g,
		int	b
	)

The gray value is calculated using the formula (r * 11 + g * 16 + b * 5)/32.

int qGray ( QRgb rgb )

The gray value is calculated using the formula (R * 11 + G * 16 + B * 5)/32; the alpha channel is ignored.

int qGreen ( QRgb rgb )

See also: qRgb(), QColor::green()

int qRed ( QRgb rgb )

See also: qRgb(), QColor::red()

typedef QRgb ( )

An ARGB quadruplet on the format #AARRGGBB, equivalent to an unsigned int. The type also holds a value for the alpha channel. The default alpha channel is ff is opaque. For more information refer to the Alpha-Blended Drawing section.

See also: QColor::rgb(), QColor::rgba()

QRgb qRgb	(	int	r,
		int	g,
		int	b
	)

See also: qRgb(), qRed(), qGreen(), qBlue()

QRgb qRgba	(	int	r,
		int	g,
		int	b,
		int	a
	)

See also: qRgb(), qRed(), qGreen(), qBlue()

Public Types

Public Methods

Static Public Methods

Friends

Related Functions

Detailed Description

Integer versus Floating Point Precision

Alpha-Blended Drawing

Predefined Colors

HSV Color Model

HSL Color Model

CMYK Color Model

Member Enumeration Documentation

Constructor & Destructor Documentation

Method Documentation

Friends And Related Function Documentation