#include <wx/colour.h>
A colour is an object representing a combination of Red, Green, and Blue (RGB) intensity values and an Alpha value, and is used to determine drawing colours.
See the entry for wxColourDatabase for how a pointer to a predefined, named colour may be returned instead of creating a new colour.
Valid RGB values are in the range 0 to 255.
You can retrieve the current system colour settings with wxSystemSettings.
Note that this class provides pairs of functions for each of the colour channels, i.e. red, green, blue and alpha values. The one word functions Red(), Green(), Blue() and Alpha() return the values of type unsigned
char
, while GetRed(), GetGreen(), GetBlue() and GetAlpha() returns the same value as unsigned
int
. According to the C++ integer promotion rules, the result of any arithmetic expression involving the former will be (signed) int
, while that of the latter will be unsigned
, which is what would be commonly expected, so the latter family of functions should be typically preferred (but they are only available since wxWidgets 3.1.6).
Predefined objects/pointers:
Public Member Functions | |
wxColour () | |
Default constructor. More... | |
wxColour (unsigned char red, unsigned char green, unsigned char blue, unsigned char alpha=wxALPHA_OPAQUE) | |
wxColour (const wxString &colourName) | |
wxColour (unsigned long colRGB) | |
wxColour (const wxColour &colour) | |
Copy constructor. More... | |
virtual unsigned char | Alpha () const |
Returns the alpha value, on platforms where alpha is not yet supported, this always returns wxALPHA_OPAQUE. More... | |
virtual unsigned char | Blue () const |
Returns the blue intensity. More... | |
unsigned int | GetAlpha () const |
Returns the alpha value, on platforms where alpha is not yet supported, this always returns wxALPHA_OPAQUE. More... | |
unsigned int | GetBlue () const |
Returns the blue intensity as unsigned int. More... | |
unsigned int | GetGreen () const |
Returns the green intensity as unsigned int. More... | |
unsigned int | GetRed () const |
Returns the red intensity as unsigned int. More... | |
virtual wxString | GetAsString (long flags=wxC2S_NAME|wxC2S_CSS_SYNTAX) const |
Converts this colour to a wxString using the given flags. More... | |
double | GetLuminance () const |
Return the perceived brightness of the colour. More... | |
wxIntPtr | GetPixel () const |
Returns a pixel value which is platform-dependent. More... | |
virtual unsigned char | Green () const |
Returns the green intensity. More... | |
virtual bool | IsOk () const |
Returns true if the colour object is valid (the colour has been initialised with RGB values). More... | |
virtual unsigned char | Red () const |
Returns the red intensity. More... | |
virtual bool | IsSolid () const |
Returns true if the color can be described using RGB values, i.e. More... | |
bool | operator!= (const wxColour &colour) const |
Tests the inequality of two colours by comparing individual red, green, blue intensities and alpha values. More... | |
wxColour & | operator= (const wxColour &colour) |
Assignment operator. More... | |
bool | operator== (const wxColour &colour) const |
Tests the equality of two colours by comparing individual red, green, blue intensities and alpha values. More... | |
wxColour & | MakeDisabled (unsigned char brightness=255) |
Make a disabled version of this colour. More... | |
wxColour | ChangeLightness (int ialpha) const |
wxColour wrapper for ChangeLightness(r,g,b,ialpha). More... | |
void | SetRGB (wxUint32 colRGB) |
Sets the RGB or RGBA colour values from a single 32 bit value. More... | |
void | SetRGBA (wxUint32 colRGBA) |
Sets the RGB or RGBA colour values from a single 32 bit value. More... | |
wxUint32 | GetRGB () const |
Gets the RGB or RGBA colour values as a single 32 bit value. More... | |
wxUint32 | GetRGBA () const |
Gets the RGB or RGBA colour values as a single 32 bit value. More... | |
void | Set (unsigned char red, unsigned char green, unsigned char blue, unsigned char alpha=wxALPHA_OPAQUE) |
Sets the RGB intensity values using the given values (first overload), extracting them from the packed long (second overload), using the given string (third overload). More... | |
void | Set (unsigned long RGB) |
Sets the RGB intensity values using the given values (first overload), extracting them from the packed long (second overload), using the given string (third overload). More... | |
bool | Set (const wxString &str) |
Sets the RGB intensity values using the given values (first overload), extracting them from the packed long (second overload), using the given string (third overload). More... | |
Public Member Functions inherited from wxObject | |
wxObject () | |
Default ctor; initializes to NULL the internal reference data. More... | |
wxObject (const wxObject &other) | |
Copy ctor. More... | |
virtual | ~wxObject () |
Destructor. More... | |
virtual wxClassInfo * | GetClassInfo () const |
This virtual function is redefined for every class that requires run-time type information, when using the wxDECLARE_CLASS macro (or similar). More... | |
wxObjectRefData * | GetRefData () const |
Returns the wxObject::m_refData pointer, i.e. the data referenced by this object. More... | |
bool | IsKindOf (const wxClassInfo *info) const |
Determines whether this class is a subclass of (or the same class as) the given class. More... | |
bool | IsSameAs (const wxObject &obj) const |
Returns true if this object has the same data pointer as obj. More... | |
void | Ref (const wxObject &clone) |
Makes this object refer to the data in clone. More... | |
void | SetRefData (wxObjectRefData *data) |
Sets the wxObject::m_refData pointer. More... | |
void | UnRef () |
Decrements the reference count in the associated data, and if it is zero, deletes the data. More... | |
void | UnShare () |
This is the same of AllocExclusive() but this method is public. More... | |
void | operator delete (void *buf) |
The delete operator is defined for debugging versions of the library only, when the identifier __WXDEBUG__ is defined. More... | |
void * | operator new (size_t size, const wxString &filename=NULL, int lineNum=0) |
The new operator is defined for debugging versions of the library only, when the identifier __WXDEBUG__ is defined. More... | |
Static Public Member Functions | |
static void | MakeMono (unsigned char *r, unsigned char *g, unsigned char *b, bool on) |
Assigns the same value to r, g, b: 0 if on is false , 255 otherwise. More... | |
static void | MakeDisabled (unsigned char *r, unsigned char *g, unsigned char *b, unsigned char brightness=255) |
Create a disabled (dimmed) colour from (in/out) rgb parameters. More... | |
static void | MakeGrey (unsigned char *r, unsigned char *g, unsigned char *b) |
Create a grey colour from (in/out) rgb parameters using integer arithmetic. More... | |
static void | MakeGrey (unsigned char *r, unsigned char *g, unsigned char *b, double weight_r, double weight_g, double weight_b) |
Create a grey colour from (in/out) rgb parameters using floating point arithmetic. More... | |
static unsigned char | AlphaBlend (unsigned char fg, unsigned char bg, double alpha) |
Blend colour, taking alpha into account. More... | |
static void | ChangeLightness (unsigned char *r, unsigned char *g, unsigned char *b, int ialpha) |
Utility function that simply darkens or lightens a color, based on the specified percentage ialpha. More... | |
Additional Inherited Members | |
Protected Member Functions inherited from wxObject | |
void | AllocExclusive () |
Ensure that this object's data is not shared with any other object. More... | |
virtual wxObjectRefData * | CreateRefData () const |
Creates a new instance of the wxObjectRefData-derived class specific to this object and returns it. More... | |
virtual wxObjectRefData * | CloneRefData (const wxObjectRefData *data) const |
Creates a new instance of the wxObjectRefData-derived class specific to this object and initializes it copying data. More... | |
Protected Attributes inherited from wxObject | |
wxObjectRefData * | m_refData |
Pointer to an object which is the object's reference-counted data. More... | |
wxColour::wxColour | ( | ) |
Default constructor.
wxColour::wxColour | ( | unsigned char | red, |
unsigned char | green, | ||
unsigned char | blue, | ||
unsigned char | alpha = wxALPHA_OPAQUE |
||
) |
red | The red value. |
green | The green value. |
blue | The blue value. |
alpha | The alpha value. Alpha values range from 0 (wxALPHA_TRANSPARENT) to 255 (wxALPHA_OPAQUE). |
wxColour::wxColour | ( | const wxString & | colourName | ) |
colourName | The colour name. |
wxColour::wxColour | ( | unsigned long | colRGB | ) |
colRGB | A packed RGB value. |
wxColour::wxColour | ( | const wxColour & | colour | ) |
Copy constructor.
|
virtual |
Returns the alpha value, on platforms where alpha is not yet supported, this always returns wxALPHA_OPAQUE.
|
static |
Blend colour, taking alpha into account.
|
virtual |
Returns the blue intensity.
wxColour wxColour::ChangeLightness | ( | int | ialpha | ) | const |
wxColour wrapper for ChangeLightness(r,g,b,ialpha).
|
static |
Utility function that simply darkens or lightens a color, based on the specified percentage ialpha.
ialpha of 0 would be make the color completely black, 200 completely white and 100 would not change the color.
unsigned int wxColour::GetAlpha | ( | ) | const |
Returns the alpha value, on platforms where alpha is not yet supported, this always returns wxALPHA_OPAQUE.
|
virtual |
Converts this colour to a wxString using the given flags.
The supported flags are wxC2S_NAME
, to obtain the colour name (e.g. wxColour(255,0,0) == "red"), wxC2S_CSS_SYNTAX
, to obtain the colour in the "rgb(r,g,b)" or "rgba(r,g,b,a)" syntax (e.g. wxColour(255,0,0,85) == "rgba(255,0,0,0.333)"), and wxC2S_HTML_SYNTAX
, to obtain the colour as "#" followed by 6 hexadecimal digits (e.g. wxColour(255,0,0) == "#FF0000").
This function returns empty string if the colour is not initialized (see IsOk()). Otherwise, the returned string is always non-empty, but the function asserts if the colour has alpha channel (i.e. is non opaque) but wxC2S_CSS_SYNTAX
(which is the only one supporting alpha) is not specified in flags.
unsigned int wxColour::GetBlue | ( | ) | const |
Returns the blue intensity as unsigned int.
unsigned int wxColour::GetGreen | ( | ) | const |
Returns the green intensity as unsigned int.
double wxColour::GetLuminance | ( | ) | const |
Return the perceived brightness of the colour.
This value is computed using the simple
formula with the coefficients taken from the RGB to YIQ conversion formula and R
, G
and B
being the values of the corresponding colour channels normalized to 0..1 range, so that the return value is 0 for black and 1 for white.
wxIntPtr wxColour::GetPixel | ( | ) | const |
Returns a pixel value which is platform-dependent.
On Windows, a COLORREF is returned. On X, an allocated pixel value is returned. If the pixel is invalid (on X, unallocated), -1
is returned.
unsigned int wxColour::GetRed | ( | ) | const |
Returns the red intensity as unsigned int.
wxUint32 wxColour::GetRGB | ( | ) | const |
Gets the RGB or RGBA colour values as a single 32 bit value.
The returned value is of the same form as expected by SetRGB() and SetRGBA().
Notice that GetRGB() returns the value with 0 as its highest byte independently of the value actually returned by Alpha(). So for a fully opaque colour, the return value of GetRGBA() is 0xFFBBGGRR
while that of GetRGB() is 0x00BBGGRR
.
wxUint32 wxColour::GetRGBA | ( | ) | const |
Gets the RGB or RGBA colour values as a single 32 bit value.
The returned value is of the same form as expected by SetRGB() and SetRGBA().
Notice that GetRGB() returns the value with 0 as its highest byte independently of the value actually returned by Alpha(). So for a fully opaque colour, the return value of GetRGBA() is 0xFFBBGGRR
while that of GetRGB() is 0x00BBGGRR
.
|
virtual |
Returns the green intensity.
|
virtual |
Returns true if the colour object is valid (the colour has been initialised with RGB values).
|
virtual |
Returns true if the color can be described using RGB values, i.e.
is solid, false if it is a pattern (currently only possible on macOS)
|
static |
Create a disabled (dimmed) colour from (in/out) rgb parameters.
wxColour& wxColour::MakeDisabled | ( | unsigned char | brightness = 255 | ) |
Make a disabled version of this colour.
This method modifies the object in place and returns the object itself.
|
static |
Create a grey colour from (in/out) rgb parameters using integer arithmetic.
|
static |
Create a grey colour from (in/out) rgb parameters using floating point arithmetic.
Defaults to using the standard ITU-T BT.601 when converting to YUV, where every pixel equals (R * weight_r) + (G * weight_g) + (B * weight_b).
|
static |
Assigns the same value to r, g, b: 0 if on is false
, 255 otherwise.
bool wxColour::operator!= | ( | const wxColour & | colour | ) | const |
Tests the inequality of two colours by comparing individual red, green, blue intensities and alpha values.
Assignment operator.
bool wxColour::operator== | ( | const wxColour & | colour | ) | const |
Tests the equality of two colours by comparing individual red, green, blue intensities and alpha values.
|
virtual |
Returns the red intensity.
bool wxColour::Set | ( | const wxString & | str | ) |
Sets the RGB intensity values using the given values (first overload), extracting them from the packed long (second overload), using the given string (third overload).
When using third form, Set() accepts: colour names (those listed in wxColourDatabase), the CSS-like "rgb(r,g,b)"
or "rgba(r,g,b,a)"
syntax (case insensitive) and the HTML-like syntax: "#"
followed by 6 hexadecimal digits for red, green, blue components.
Returns true if the conversion was successful, false otherwise.
void wxColour::Set | ( | unsigned char | red, |
unsigned char | green, | ||
unsigned char | blue, | ||
unsigned char | alpha = wxALPHA_OPAQUE |
||
) |
Sets the RGB intensity values using the given values (first overload), extracting them from the packed long (second overload), using the given string (third overload).
When using third form, Set() accepts: colour names (those listed in wxColourDatabase), the CSS-like "rgb(r,g,b)"
or "rgba(r,g,b,a)"
syntax (case insensitive) and the HTML-like syntax: "#"
followed by 6 hexadecimal digits for red, green, blue components.
Returns true if the conversion was successful, false otherwise.
void wxColour::Set | ( | unsigned long | RGB | ) |
Sets the RGB intensity values using the given values (first overload), extracting them from the packed long (second overload), using the given string (third overload).
When using third form, Set() accepts: colour names (those listed in wxColourDatabase), the CSS-like "rgb(r,g,b)"
or "rgba(r,g,b,a)"
syntax (case insensitive) and the HTML-like syntax: "#"
followed by 6 hexadecimal digits for red, green, blue components.
Returns true if the conversion was successful, false otherwise.
void wxColour::SetRGB | ( | wxUint32 | colRGB | ) |
Sets the RGB or RGBA colour values from a single 32 bit value.
The arguments colRGB and colRGBA should be of the form 0x00BBGGRR and 0xAABBGGRR respectively where 0xRR
, 0xGG
, 0xBB
and 0xAA
are the values of the red, green, blue and alpha components.
Notice the right-to-left order of components!
void wxColour::SetRGBA | ( | wxUint32 | colRGBA | ) |
Sets the RGB or RGBA colour values from a single 32 bit value.
The arguments colRGB and colRGBA should be of the form 0x00BBGGRR and 0xAABBGGRR respectively where 0xRR
, 0xGG
, 0xBB
and 0xAA
are the values of the red, green, blue and alpha components.
Notice the right-to-left order of components!