Open CASCADE Technology  7.2.0
Public Member Functions | Static Public Member Functions

Quantity_Color Class Reference

This class allows the definition of a colour. The names of the colours are from the X11 specification. color object may be used for numerous applicative purposes. A color is defined by: More...

#include <Quantity_Color.hxx>

Public Member Functions

 Quantity_Color ()
 Creates a colour with the default value of Colour name : YELLOW. More...
 
 Quantity_Color (const Quantity_NameOfColor AName)
 Creates the colour <AName>. More...
 
 Quantity_Color (const Standard_Real theR1, const Standard_Real theR2, const Standard_Real theR3, const Quantity_TypeOfColor theType)
 Creates a color according to the definition system theType. Quantity_TOC_RGB: More...
 
 Quantity_Color (const NCollection_Vec3< float > &theRgb)
 Define color from RGB values. More...
 
void ChangeContrast (const Standard_Real ADelta)
 Increases or decreases the contrast by <ADelta>. <ADelta> is a percentage. Any value greater than zero will increase the contrast. The variation is expressed as a percentage of the current value. It is a variation of the saturation. More...
 
void ChangeIntensity (const Standard_Real ADelta)
 Increases or decreases the intensity by <ADelta>. <ADelta> is a percentage. Any value greater than zero will increase the intensity. The variation is expressed as a percentage of the current value. It is a variation of the lightness. More...
 
void SetValues (const Quantity_NameOfColor AName)
 Updates the colour <me> from the definition of the colour <AName>. More...
 
void SetValues (const Standard_Real theR1, const Standard_Real theR2, const Standard_Real theR3, const Quantity_TypeOfColor theType)
 Updates a color according to the mode specified by theType. TOC_RGB: More...
 
void Delta (const Quantity_Color &AColor, Standard_Real &DC, Standard_Real &DI) const
 Returns the percentage change of contrast and intensity between <me> and <AColor>. <DC> and <DI> are percentages, either positive or negative. The calculation is with respect to the current value of <me> If <DC> is positive then <me> is more contrasty. If <DI> is positive then <me> is more intense. More...
 
Standard_Real Distance (const Quantity_Color &AColor) const
 Returns the distance between two colours. It's a value between 0 and the square root of 3 (the black/white distance) More...
 
Standard_Real SquareDistance (const Quantity_Color &AColor) const
 Returns the square of distance between two colours. More...
 
Standard_Real Blue () const
 Returns the Blue component (quantity of blue) of the color within range [0.0; 1.0]. More...
 
Standard_Real Green () const
 Returns the Green component (quantity of green) of the color within range [0.0; 1.0]. More...
 
Standard_Real Hue () const
 Returns the Hue component (hue angle) of the color in degrees within range [0.0; 360.0], 0.0 being Red. -1.0 is a special value reserved for grayscale color (S should be 0.0) More...
 
Standard_Boolean IsDifferent (const Quantity_Color &Other) const
 Returns Standard_True if the distance between <me> and <Other> is greater than Epsilon (). More...
 
Standard_Boolean operator!= (const Quantity_Color &Other) const
 
Standard_Boolean IsEqual (const Quantity_Color &Other) const
 Returns true if the Other color is. More...
 
Standard_Boolean operator== (const Quantity_Color &Other) const
 
Standard_Real Light () const
 Returns the Light component (value of the lightness) of the color within range [0.0; 1.0]. More...
 
Quantity_NameOfColor Name () const
 Returns the name of the color defined by its quantities of red R, green G and blue B; more precisely this is the nearest color from the Quantity_NameOfColor enumeration. Exceptions Standard_OutOfRange if R, G or B is less than 0. or greater than 1. More...
 
Standard_Real Red () const
 Returns the Red component (quantity of red) of the color within range [0.0; 1.0]. More...
 
Standard_Real Saturation () const
 Returns the Saturation component (value of the saturation) of the color within range [0.0; 1.0]. More...
 
 operator const NCollection_Vec3< float > & () const
 Return the color as vector of 3 float elements. More...
 
void Values (Standard_Real &theR1, Standard_Real &theR2, Standard_Real &theR3, const Quantity_TypeOfColor theType) const
 Returns in theR1, theR2 and theR3 the components of this color according to the color system definition theType. If theType is Quantity_TOC_RGB: More...
 

Static Public Member Functions

static void SetEpsilon (const Standard_Real AnEpsilon)
 Sets the specified value used to compare <me> and an other color in IsDifferent and in IsEqual methods. Warning: The default value is 0.0001. More...
 
static Standard_Real Epsilon ()
 Returns the specified value used to compare <me> and an other color in IsDifferent and in IsEqual methods. More...
 
static Quantity_NameOfColor Name (const Standard_Real R, const Standard_Real G, const Standard_Real B)
 Returns the name of the colour for which the RGB components are nearest to <R>, <G> and . More...
 
static Standard_CString StringName (const Quantity_NameOfColor AColor)
 Returns the name of the color identified by AName in the Quantity_NameOfColor enumeration. For example, the name of the color which corresponds to Quantity_NOC_BLACK is "BLACK". Exceptions Standard_OutOfRange if AName in not known in the Quantity_NameOfColor enumeration. More...
 
static Standard_Boolean ColorFromName (const Standard_CString theName, Quantity_NameOfColor &theColor)
 Finds color from predefined names. For example, the name of the color which corresponds to "BLACK" is Quantity_NOC_BLACK. Returns false if name is unknown. More...
 
static void HlsRgb (const Standard_Real H, const Standard_Real L, const Standard_Real S, Standard_Real &R, Standard_Real &G, Standard_Real &B)
 Converts HLS components into RGB ones. More...
 
static void RgbHls (const Standard_Real R, const Standard_Real G, const Standard_Real B, Standard_Real &H, Standard_Real &L, Standard_Real &S)
 Converts RGB components into HLS ones. More...
 
static void Color2argb (const Quantity_Color &theColor, Standard_Integer &theARGB)
 Convert the Color value to ARGB integer value. theARGB has Alpha equal to zero, so the output is formatted as 0x00RRGGBB. More...
 
static void Argb2color (const Standard_Integer theARGB, Quantity_Color &theColor)
 Convert integer ARGB value to Color. Alpha bits are ignored. More...
 
static void Test ()
 Internal test. More...
 

Detailed Description

This class allows the definition of a colour. The names of the colours are from the X11 specification. color object may be used for numerous applicative purposes. A color is defined by:

Constructor & Destructor Documentation

◆ Quantity_Color() [1/4]

Quantity_Color::Quantity_Color ( )

Creates a colour with the default value of Colour name : YELLOW.

◆ Quantity_Color() [2/4]

Quantity_Color::Quantity_Color ( const Quantity_NameOfColor  AName)

Creates the colour <AName>.

◆ Quantity_Color() [3/4]

Quantity_Color::Quantity_Color ( const Standard_Real  theR1,
const Standard_Real  theR2,
const Standard_Real  theR3,
const Quantity_TypeOfColor  theType 
)

Creates a color according to the definition system theType. Quantity_TOC_RGB:

  • theR1 the value of Red within range [0.0; 1.0]
  • theR2 the value of Green within range [0.0; 1.0]
  • theR3 the value of Blue within range [0.0; 1.0]

Quantity_TOC_HLS:

  • theR1 is the Hue (H) angle in degrees within range [0.0; 360.0], 0.0 being Red. Value -1.0 is a special value reserved for grayscale color (S should be 0.0).
  • theR2 is the Lightness (L) within range [0.0; 1.0]
  • theR3 is the Saturation (S) within range [0.0; 1.0]

◆ Quantity_Color() [4/4]

Quantity_Color::Quantity_Color ( const NCollection_Vec3< float > &  theRgb)
explicit

Define color from RGB values.

Member Function Documentation

◆ Argb2color()

static void Quantity_Color::Argb2color ( const Standard_Integer  theARGB,
Quantity_Color theColor 
)
static

Convert integer ARGB value to Color. Alpha bits are ignored.

◆ Blue()

Standard_Real Quantity_Color::Blue ( ) const

Returns the Blue component (quantity of blue) of the color within range [0.0; 1.0].

◆ ChangeContrast()

void Quantity_Color::ChangeContrast ( const Standard_Real  ADelta)

Increases or decreases the contrast by <ADelta>. <ADelta> is a percentage. Any value greater than zero will increase the contrast. The variation is expressed as a percentage of the current value. It is a variation of the saturation.

◆ ChangeIntensity()

void Quantity_Color::ChangeIntensity ( const Standard_Real  ADelta)

Increases or decreases the intensity by <ADelta>. <ADelta> is a percentage. Any value greater than zero will increase the intensity. The variation is expressed as a percentage of the current value. It is a variation of the lightness.

◆ Color2argb()

static void Quantity_Color::Color2argb ( const Quantity_Color theColor,
Standard_Integer theARGB 
)
static

Convert the Color value to ARGB integer value. theARGB has Alpha equal to zero, so the output is formatted as 0x00RRGGBB.

◆ ColorFromName()

static Standard_Boolean Quantity_Color::ColorFromName ( const Standard_CString  theName,
Quantity_NameOfColor theColor 
)
static

Finds color from predefined names. For example, the name of the color which corresponds to "BLACK" is Quantity_NOC_BLACK. Returns false if name is unknown.

◆ Delta()

void Quantity_Color::Delta ( const Quantity_Color AColor,
Standard_Real DC,
Standard_Real DI 
) const

Returns the percentage change of contrast and intensity between <me> and <AColor>. <DC> and <DI> are percentages, either positive or negative. The calculation is with respect to the current value of <me> If <DC> is positive then <me> is more contrasty. If <DI> is positive then <me> is more intense.

◆ Distance()

Standard_Real Quantity_Color::Distance ( const Quantity_Color AColor) const

Returns the distance between two colours. It's a value between 0 and the square root of 3 (the black/white distance)

◆ Epsilon()

static Standard_Real Quantity_Color::Epsilon ( )
static

Returns the specified value used to compare <me> and an other color in IsDifferent and in IsEqual methods.

◆ Green()

Standard_Real Quantity_Color::Green ( ) const

Returns the Green component (quantity of green) of the color within range [0.0; 1.0].

◆ HlsRgb()

static void Quantity_Color::HlsRgb ( const Standard_Real  H,
const Standard_Real  L,
const Standard_Real  S,
Standard_Real R,
Standard_Real G,
Standard_Real B 
)
static

Converts HLS components into RGB ones.

◆ Hue()

Standard_Real Quantity_Color::Hue ( ) const

Returns the Hue component (hue angle) of the color in degrees within range [0.0; 360.0], 0.0 being Red. -1.0 is a special value reserved for grayscale color (S should be 0.0)

◆ IsDifferent()

Standard_Boolean Quantity_Color::IsDifferent ( const Quantity_Color Other) const

Returns Standard_True if the distance between <me> and <Other> is greater than Epsilon ().

◆ IsEqual()

Standard_Boolean Quantity_Color::IsEqual ( const Quantity_Color Other) const

Returns true if the Other color is.

  • different from, or
  • equal to this color. Two colors are considered to be equal if their distance is no greater than Epsilon(). These methods are aliases of operator != and operator ==.

◆ Light()

Standard_Real Quantity_Color::Light ( ) const

Returns the Light component (value of the lightness) of the color within range [0.0; 1.0].

◆ Name() [1/2]

Quantity_NameOfColor Quantity_Color::Name ( ) const

Returns the name of the color defined by its quantities of red R, green G and blue B; more precisely this is the nearest color from the Quantity_NameOfColor enumeration. Exceptions Standard_OutOfRange if R, G or B is less than 0. or greater than 1.

◆ Name() [2/2]

static Quantity_NameOfColor Quantity_Color::Name ( const Standard_Real  R,
const Standard_Real  G,
const Standard_Real  B 
)
static

Returns the name of the colour for which the RGB components are nearest to <R>, <G> and .

◆ operator const NCollection_Vec3< float > &()

Quantity_Color::operator const NCollection_Vec3< float > & ( ) const
inline

Return the color as vector of 3 float elements.

◆ operator!=()

Standard_Boolean Quantity_Color::operator!= ( const Quantity_Color Other) const
inline

◆ operator==()

Standard_Boolean Quantity_Color::operator== ( const Quantity_Color Other) const
inline

◆ Red()

Standard_Real Quantity_Color::Red ( ) const

Returns the Red component (quantity of red) of the color within range [0.0; 1.0].

◆ RgbHls()

static void Quantity_Color::RgbHls ( const Standard_Real  R,
const Standard_Real  G,
const Standard_Real  B,
Standard_Real H,
Standard_Real L,
Standard_Real S 
)
static

Converts RGB components into HLS ones.

◆ Saturation()

Standard_Real Quantity_Color::Saturation ( ) const

Returns the Saturation component (value of the saturation) of the color within range [0.0; 1.0].

◆ SetEpsilon()

static void Quantity_Color::SetEpsilon ( const Standard_Real  AnEpsilon)
static

Sets the specified value used to compare <me> and an other color in IsDifferent and in IsEqual methods. Warning: The default value is 0.0001.

◆ SetValues() [1/2]

void Quantity_Color::SetValues ( const Quantity_NameOfColor  AName)

Updates the colour <me> from the definition of the colour <AName>.

◆ SetValues() [2/2]

void Quantity_Color::SetValues ( const Standard_Real  theR1,
const Standard_Real  theR2,
const Standard_Real  theR3,
const Quantity_TypeOfColor  theType 
)

Updates a color according to the mode specified by theType. TOC_RGB:

  • theR1 the value of Red within range [0.0; 1.0]
  • theR2 the value of Green within range [0.0; 1.0]
  • theR3 the value of Blue within range [0.0; 1.0]

TOC_HLS:

  • theR1 is the Hue (H) angle in degrees within range [0.0; 360.0], 0.0 being Red. -1.0 is a special value reserved for grayscale color (S should be 0.0).
  • theR2 is the Lightness (L) within range [0.0; 1.0]
  • theR3 is the Saturation (S) within range [0.0; 1.0]

◆ SquareDistance()

Standard_Real Quantity_Color::SquareDistance ( const Quantity_Color AColor) const

Returns the square of distance between two colours.

◆ StringName()

static Standard_CString Quantity_Color::StringName ( const Quantity_NameOfColor  AColor)
static

Returns the name of the color identified by AName in the Quantity_NameOfColor enumeration. For example, the name of the color which corresponds to Quantity_NOC_BLACK is "BLACK". Exceptions Standard_OutOfRange if AName in not known in the Quantity_NameOfColor enumeration.

◆ Test()

static void Quantity_Color::Test ( )
static

Internal test.

◆ Values()

void Quantity_Color::Values ( Standard_Real theR1,
Standard_Real theR2,
Standard_Real theR3,
const Quantity_TypeOfColor  theType 
) const

Returns in theR1, theR2 and theR3 the components of this color according to the color system definition theType. If theType is Quantity_TOC_RGB:

  • theR1 the value of Red between 0.0 and 1.0
  • theR2 the value of Green between 0.0 and 1.0
  • theR3 the value of Blue between 0.0 and 1.0 If theType is Quantity_TOC_HLS:
  • theR1 is the Hue (H) angle in degrees within range [0.0; 360.0], 0.0 being Red. -1.0 is a special value reserved for grayscale color (S should be 0.0).
  • theR2 is the Lightness (L) within range [0.0; 1.0]
  • theR3 is the Saturation (S) within range [0.0; 1.0]

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