Colour Class Reference

Represents a colour, also including a transparency value. More...

#include <juce_Colour.h>

Public Member Functions
	Colour ()=default
	Creates a transparent black colour.
	Colour (const Colour &)=default
	Creates a copy of another Colour object.
	Colour (uint32 argb) noexcept
	Creates a colour from a 32-bit ARGB value.
	Colour (uint8 red, uint8 green, uint8 blue) noexcept
	Creates an opaque colour using 8-bit red, green and blue values.
	Colour (uint8 red, uint8 green, uint8 blue, uint8 alpha) noexcept
	Creates a colour using 8-bit red, green, blue and alpha values.
	Colour (uint8 red, uint8 green, uint8 blue, float alpha) noexcept
	Creates a colour from 8-bit red, green, and blue values, and a floating-point alpha.
	Colour (float hue, float saturation, float brightness, uint8 alpha) noexcept
	Creates a colour using floating point hue, saturation and brightness values, and an 8-bit alpha.
	Colour (float hue, float saturation, float brightness, float alpha) noexcept
	Creates a colour using floating point hue, saturation, brightness and alpha values.
	Colour (PixelARGB argb) noexcept
	Creates a colour using a PixelARGB object.
	Colour (PixelRGB rgb) noexcept
	Creates a colour using a PixelRGB object.
	Colour (PixelAlpha alpha) noexcept
	Creates a colour using a PixelAlpha object.
	~Colour ()=default
	Destructor.
Colour &	operator= (const Colour &)=default
	Copies another Colour object.
bool	operator== (const Colour &other) const noexcept
	Compares two colours.
bool	operator!= (const Colour &other) const noexcept
	Compares two colours.
uint8	getRed () const noexcept
	Returns the red component of this colour.
uint8	getGreen () const noexcept
	Returns the green component of this colour.
uint8	getBlue () const noexcept
	Returns the blue component of this colour.
float	getFloatRed () const noexcept
	Returns the red component of this colour as a floating point value.
float	getFloatGreen () const noexcept
	Returns the green component of this colour as a floating point value.
float	getFloatBlue () const noexcept
	Returns the blue component of this colour as a floating point value.
PixelARGB	getPixelARGB () const noexcept
	Returns a premultiplied ARGB pixel object that represents this colour.
PixelARGB	getNonPremultipliedPixelARGB () const noexcept
	Returns an ARGB pixel object that represents this colour.
uint32	getARGB () const noexcept
	Returns a 32-bit integer that represents this colour.
uint8	getAlpha () const noexcept
	Returns the colour's alpha (opacity).
float	getFloatAlpha () const noexcept
	Returns the colour's alpha (opacity) as a floating point value.
bool	isOpaque () const noexcept
	Returns true if this colour is completely opaque.
bool	isTransparent () const noexcept
	Returns true if this colour is completely transparent.
Colour	withAlpha (uint8 newAlpha) const noexcept
	Returns a colour that's the same colour as this one, but with a new alpha value.
Colour	withAlpha (float newAlpha) const noexcept
	Returns a colour that's the same colour as this one, but with a new alpha value.
Colour	withMultipliedAlpha (float alphaMultiplier) const noexcept
	Returns a colour that's the same colour as this one, but with a modified alpha value.
Colour	overlaidWith (Colour foregroundColour) const noexcept
	Returns a colour that is the result of alpha-compositing a new colour over this one.
Colour	interpolatedWith (Colour other, float proportionOfOther) const noexcept
	Returns a colour that lies somewhere between this one and another.
float	getHue () const noexcept
	Returns the colour's hue component.
float	getSaturation () const noexcept
	Returns the colour's saturation component.
float	getSaturationHSL () const noexcept
	Returns the colour's saturation component as represented in the HSL colour space.
float	getBrightness () const noexcept
	Returns the colour's brightness component.
float	getLightness () const noexcept
	Returns the colour's lightness component.
float	getPerceivedBrightness () const noexcept
	Returns a skewed brightness value, adjusted to better reflect the way the human eye responds to different colour channels.
void	getHSB (float &hue, float &saturation, float &brightness) const noexcept
	Returns the colour's hue, saturation and brightness components all at once.
void	getHSL (float &hue, float &saturation, float &lightness) const noexcept
	Returns the colour's hue, saturation and lightness components all at once.
Colour	withHue (float newHue) const noexcept
	Returns a copy of this colour with a different hue.
Colour	withSaturation (float newSaturation) const noexcept
	Returns a copy of this colour with a different saturation.
Colour	withSaturationHSL (float newSaturation) const noexcept
	Returns a copy of this colour with a different saturation in the HSL colour space.
Colour	withBrightness (float newBrightness) const noexcept
	Returns a copy of this colour with a different brightness.
Colour	withLightness (float newLightness) const noexcept
	Returns a copy of this colour with a different lightness.
Colour	withRotatedHue (float amountToRotate) const noexcept
	Returns a copy of this colour with its hue rotated.
Colour	withMultipliedSaturation (float multiplier) const noexcept
	Returns a copy of this colour with its saturation multiplied by the given value.
Colour	withMultipliedSaturationHSL (float multiplier) const noexcept
	Returns a copy of this colour with its saturation multiplied by the given value.
Colour	withMultipliedBrightness (float amount) const noexcept
	Returns a copy of this colour with its brightness multiplied by the given value.
Colour	withMultipliedLightness (float amount) const noexcept
	Returns a copy of this colour with its lightness multiplied by the given value.
Colour	brighter (float amountBrighter=0.4f) const noexcept
	Returns a brighter version of this colour.
Colour	darker (float amountDarker=0.4f) const noexcept
	Returns a darker version of this colour.
Colour	contrasting (float amount=1.0f) const noexcept
	Returns a colour that will be clearly visible against this colour.
Colour	contrasting (Colour targetColour, float minLuminosityDiff) const noexcept
	Returns a colour that is as close as possible to a target colour whilst still being in contrast to this one.
String	toString () const
	Returns a stringified version of this colour.
String	toDisplayString (bool includeAlphaValue) const
	Returns the colour as a hex string in the form RRGGBB or AARRGGBB.

Static Public Member Functions
static Colour	fromRGB (uint8 red, uint8 green, uint8 blue) noexcept
	Creates an opaque colour using 8-bit red, green and blue values.
static Colour	fromRGBA (uint8 red, uint8 green, uint8 blue, uint8 alpha) noexcept
	Creates a colour using 8-bit red, green, blue and alpha values.
static Colour	fromFloatRGBA (float red, float green, float blue, float alpha) noexcept
	Creates a colour using floating point red, green, blue and alpha values.
static Colour	fromHSV (float hue, float saturation, float brightness, float alpha) noexcept
	Creates a colour using floating point hue, saturation, brightness and alpha values.
static Colour	fromHSL (float hue, float saturation, float lightness, float alpha) noexcept
	Creates a colour using floating point hue, saturation, lightness and alpha values.
static Colour	contrasting (Colour colour1, Colour colour2) noexcept
	Returns a colour that contrasts against two colours.
static Colour	greyLevel (float brightness) noexcept
	Returns an opaque shade of grey.
static Colour	fromString (StringRef encodedColourString)
	Reads the colour from a string that was created with toString().

Detailed Description

Represents a colour, also including a transparency value.

The colour is stored internally as unsigned 8-bit red, green, blue and alpha values.

Constructor & Destructor Documentation

Colour() [1/11]

Colour::Colour ( )

default

Creates a transparent black colour.

Colour() [2/11]

Colour::Colour ( const Colour & )

default

Creates a copy of another Colour object.

Colour() [3/11]

Colour::Colour ( uint32 argb )

explicitnoexcept

Creates a colour from a 32-bit ARGB value.

The format of this number is: ((alpha << 24) | (red << 16) | (green << 8) | blue).

All components in the range 0x00 to 0xff. An alpha of 0x00 is completely transparent, alpha of 0xff is opaque.

See also

getPixelARGB

Colour() [4/11]

Colour::Colour ( uint8 red, uint8 green, uint8 blue )

noexcept

Creates an opaque colour using 8-bit red, green and blue values.

Colour() [5/11]

Colour::Colour ( uint8 red, uint8 green, uint8 blue, uint8 alpha )

noexcept

Creates a colour using 8-bit red, green, blue and alpha values.

Colour() [6/11]

Colour::Colour ( uint8 red, uint8 green, uint8 blue, float alpha )

noexcept

Creates a colour from 8-bit red, green, and blue values, and a floating-point alpha.

Alpha of 0.0 is transparent, alpha of 1.0f is opaque. Values outside the valid range will be clipped.

Colour() [7/11]

Colour::Colour ( float hue, float saturation, float brightness, uint8 alpha )

noexcept

Creates a colour using floating point hue, saturation and brightness values, and an 8-bit alpha.

The floating point values must be between 0.0 and 1.0. An alpha of 0x00 is completely transparent, alpha of 0xff is opaque. Values outside the valid range will be clipped.

Colour() [8/11]

Colour::Colour ( float hue, float saturation, float brightness, float alpha )

noexcept

Creates a colour using floating point hue, saturation, brightness and alpha values.

All values must be between 0.0 and 1.0. Numbers outside the valid range will be clipped.

Colour() [9/11]

Colour::Colour ( PixelARGB argb )

noexcept

Creates a colour using a PixelARGB object.

This function assumes that the argb pixel is not premultiplied.

Colour() [10/11]

Colour::Colour ( PixelRGB rgb )

noexcept

Creates a colour using a PixelRGB object.

Colour() [11/11]

Colour::Colour ( PixelAlpha alpha )

noexcept

Creates a colour using a PixelAlpha object.

~Colour()

Colour::~Colour ( )

default

Destructor.

Member Function Documentation

fromRGB()

static Colour Colour::fromRGB ( uint8 red, uint8 green, uint8 blue )

staticnoexcept

Creates an opaque colour using 8-bit red, green and blue values.

fromRGBA()

static Colour Colour::fromRGBA ( uint8 red, uint8 green, uint8 blue, uint8 alpha )

staticnoexcept

Creates a colour using 8-bit red, green, blue and alpha values.

fromFloatRGBA()

static Colour Colour::fromFloatRGBA ( float red, float green, float blue, float alpha )

staticnoexcept

Creates a colour using floating point red, green, blue and alpha values.

Numbers outside the range 0..1 will be clipped.

fromHSV()

static Colour Colour::fromHSV ( float hue, float saturation, float brightness, float alpha )

staticnoexcept

Creates a colour using floating point hue, saturation, brightness and alpha values.

All values must be between 0.0 and 1.0. Numbers outside the valid range will be clipped.

fromHSL()

static Colour Colour::fromHSL ( float hue, float saturation, float lightness, float alpha )

staticnoexcept

Creates a colour using floating point hue, saturation, lightness and alpha values.

All values must be between 0.0 and 1.0. Numbers outside the valid range will be clipped.

operator=()

Colour & Colour::operator= ( const Colour & )

default

Copies another Colour object.

operator==()

bool Colour::operator== ( const Colour & other ) const

noexcept

Compares two colours.

operator!=()

bool Colour::operator!= ( const Colour & other ) const

noexcept

Compares two colours.

getRed()

uint8 Colour::getRed ( ) const

noexcept

Returns the red component of this colour.

Returns

a value between 0x00 and 0xff.

getGreen()

uint8 Colour::getGreen ( ) const

noexcept

Returns the green component of this colour.

Returns

a value between 0x00 and 0xff.

getBlue()

uint8 Colour::getBlue ( ) const

noexcept

Returns the blue component of this colour.

Returns

a value between 0x00 and 0xff.

getFloatRed()

float Colour::getFloatRed ( ) const

noexcept

Returns the red component of this colour as a floating point value.

Returns

a value between 0.0 and 1.0

getFloatGreen()

float Colour::getFloatGreen ( ) const

noexcept

Returns the green component of this colour as a floating point value.

Returns

a value between 0.0 and 1.0

getFloatBlue()

float Colour::getFloatBlue ( ) const

noexcept

Returns the blue component of this colour as a floating point value.

Returns

a value between 0.0 and 1.0

getPixelARGB()

PixelARGB Colour::getPixelARGB ( ) const

noexcept

Returns a premultiplied ARGB pixel object that represents this colour.

getNonPremultipliedPixelARGB()

PixelARGB Colour::getNonPremultipliedPixelARGB ( ) const

noexcept

Returns an ARGB pixel object that represents this colour.

getARGB()

uint32 Colour::getARGB ( ) const

noexcept

Returns a 32-bit integer that represents this colour.

The format of this number is: ((alpha << 24) | (red << 16) | (green << 8) | blue).

getAlpha()

uint8 Colour::getAlpha ( ) const

noexcept

Returns the colour's alpha (opacity).

Alpha of 0x00 is completely transparent, 0xff is completely opaque.

References PixelARGB::getAlpha().

getFloatAlpha()

float Colour::getFloatAlpha ( ) const

noexcept

Returns the colour's alpha (opacity) as a floating point value.

Alpha of 0.0 is completely transparent, 1.0 is completely opaque.

isOpaque()

bool Colour::isOpaque ( ) const

noexcept

Returns true if this colour is completely opaque.

Equivalent to (getAlpha() == 0xff).

Referenced by WebBrowserComponent::Options::WinWebView2::withBackgroundColour().

isTransparent()

bool Colour::isTransparent ( ) const

noexcept

Returns true if this colour is completely transparent.

Equivalent to (getAlpha() == 0x00).

Referenced by WebBrowserComponent::Options::WinWebView2::withBackgroundColour().

withAlpha() [1/2]

Colour Colour::withAlpha ( uint8 newAlpha ) const

noexcept

Returns a colour that's the same colour as this one, but with a new alpha value.

withAlpha() [2/2]

Colour Colour::withAlpha ( float newAlpha ) const

noexcept

Returns a colour that's the same colour as this one, but with a new alpha value.

withMultipliedAlpha()

Colour Colour::withMultipliedAlpha ( float alphaMultiplier ) const

noexcept

Returns a colour that's the same colour as this one, but with a modified alpha value.

The new colour's alpha will be this object's alpha multiplied by the value passed-in.

overlaidWith()

Colour Colour::overlaidWith ( Colour foregroundColour ) const

noexcept

Returns a colour that is the result of alpha-compositing a new colour over this one.

If the foreground colour is semi-transparent, it is blended onto this colour accordingly.

interpolatedWith()

Colour Colour::interpolatedWith ( Colour other, float proportionOfOther ) const

noexcept

Returns a colour that lies somewhere between this one and another.

If amountOfOther is zero, the result is 100% this colour, if amountOfOther is 1.0, the result is 100% of the other colour.

getHue()

float Colour::getHue ( ) const

noexcept

Returns the colour's hue component.

The value returned is in the range 0.0 to 1.0

getSaturation()

float Colour::getSaturation ( ) const

noexcept

Returns the colour's saturation component.

The value returned is in the range 0.0 to 1.0

getSaturationHSL()

float Colour::getSaturationHSL ( ) const

noexcept

Returns the colour's saturation component as represented in the HSL colour space.

The value returned is in the range 0.0 to 1.0

getBrightness()

float Colour::getBrightness ( ) const

noexcept

Returns the colour's brightness component.

The value returned is in the range 0.0 to 1.0

getLightness()

float Colour::getLightness ( ) const

noexcept

Returns the colour's lightness component.

The value returned is in the range 0.0 to 1.0

getPerceivedBrightness()

float Colour::getPerceivedBrightness ( ) const

noexcept

Returns a skewed brightness value, adjusted to better reflect the way the human eye responds to different colour channels.

This makes it better than getBrightness() for comparing differences in brightness.

getHSB()

void Colour::getHSB ( float & hue, float & saturation, float & brightness ) const

noexcept

Returns the colour's hue, saturation and brightness components all at once.

The values returned are in the range 0.0 to 1.0

getHSL()

void Colour::getHSL ( float & hue, float & saturation, float & lightness ) const

noexcept

Returns the colour's hue, saturation and lightness components all at once.

The values returned are in the range 0.0 to 1.0

withHue()

Colour Colour::withHue ( float newHue ) const

nodiscardnoexcept

Returns a copy of this colour with a different hue.

withSaturation()

Colour Colour::withSaturation ( float newSaturation ) const

nodiscardnoexcept

Returns a copy of this colour with a different saturation.

withSaturationHSL()

Colour Colour::withSaturationHSL ( float newSaturation ) const

nodiscardnoexcept

Returns a copy of this colour with a different saturation in the HSL colour space.

withBrightness()

Colour Colour::withBrightness ( float newBrightness ) const

nodiscardnoexcept

Returns a copy of this colour with a different brightness.

See also

brighter, darker, withMultipliedBrightness

withLightness()

Colour Colour::withLightness ( float newLightness ) const

nodiscardnoexcept

Returns a copy of this colour with a different lightness.

See also

lighter, darker, withMultipliedLightness

withRotatedHue()

Colour Colour::withRotatedHue ( float amountToRotate ) const

nodiscardnoexcept

Returns a copy of this colour with its hue rotated.

The new colour's hue is ((this->getHue() + amountToRotate) % 1.0)

See also

brighter, darker, withMultipliedBrightness

withMultipliedSaturation()

Colour Colour::withMultipliedSaturation ( float multiplier ) const

nodiscardnoexcept

Returns a copy of this colour with its saturation multiplied by the given value.

The new colour's saturation is (this->getSaturation() * multiplier) (the result is clipped to legal limits).

withMultipliedSaturationHSL()

Colour Colour::withMultipliedSaturationHSL ( float multiplier ) const

nodiscardnoexcept

Returns a copy of this colour with its saturation multiplied by the given value.

The new colour's saturation is (this->getSaturation() * multiplier) (the result is clipped to legal limits).

This will be in the HSL colour space.

withMultipliedBrightness()

Colour Colour::withMultipliedBrightness ( float amount ) const

nodiscardnoexcept

Returns a copy of this colour with its brightness multiplied by the given value.

The new colour's brightness is (this->getBrightness() * multiplier) (the result is clipped to legal limits).

withMultipliedLightness()

Colour Colour::withMultipliedLightness ( float amount ) const

nodiscardnoexcept

Returns a copy of this colour with its lightness multiplied by the given value.

The new colour's lightness is (this->lightness() * multiplier) (the result is clipped to legal limits).

brighter()

Colour Colour::brighter ( float amountBrighter = 0.4f ) const

nodiscardnoexcept

Returns a brighter version of this colour.

Parameters

amountBrighter

how much brighter to make it - a value greater than or equal to 0, where 0 is unchanged, and higher values make it brighter

See also

withMultipliedBrightness

darker()

Colour Colour::darker ( float amountDarker = 0.4f ) const

nodiscardnoexcept

Returns a darker version of this colour.

Parameters

amountDarker

how much darker to make it - a value greater than or equal to 0, where 0 is unchanged, and higher values make it darker

See also

withMultipliedBrightness

contrasting() [1/3]

Colour Colour::contrasting ( float amount = 1.0f ) const

nodiscardnoexcept

Returns a colour that will be clearly visible against this colour.

The amount parameter indicates how contrasting the new colour should be, so e.g. Colours::black.contrasting (0.1f) will return a colour that's just a little bit lighter; Colours::black.contrasting (1.0f) will return white; Colours::white.contrasting (1.0f) will return black, etc.

contrasting() [2/3]

Colour Colour::contrasting ( Colour targetColour, float minLuminosityDiff ) const

nodiscardnoexcept

Returns a colour that is as close as possible to a target colour whilst still being in contrast to this one.

The colour that is returned will be the targetColour, but with its luminosity nudged up or down so that it differs from the luminosity of this colour by at least the amount specified by minLuminosityDiff.

contrasting() [3/3]

static Colour Colour::contrasting ( Colour colour1, Colour colour2 )

staticnodiscardnoexcept

Returns a colour that contrasts against two colours.

Looks for a colour that contrasts with both of the colours passed-in. Handy for things like choosing a highlight colour in text editors, etc.

greyLevel()

static Colour Colour::greyLevel ( float brightness )

staticnodiscardnoexcept

Returns an opaque shade of grey.

Parameters

brightness

the level of grey to return - 0 is black, 1.0 is white

toString()

String Colour::toString

(

)

const

Returns a stringified version of this colour.

The string can be turned back into a colour using the fromString() method.

fromString()

static Colour Colour::fromString ( StringRef encodedColourString )

staticnodiscard

Reads the colour from a string that was created with toString().

toDisplayString()

String Colour::toDisplayString

(

bool

includeAlphaValue

)

const

Returns the colour as a hex string in the form RRGGBB or AARRGGBB.

---

The documentation for this class was generated from the following file:

• juce_Colour.h