wxPalette Class Reference
[Graphics Device Interface (GDI)]

#include <wx/palette.h>

Inheritance diagram for wxPalette:

List of all members.

---

Detailed Description

A palette is a table that maps pixel values to RGB colours. It allows the colours of a low-depth bitmap, for example, to be mapped to the available colours in a display. The notion of palettes is becoming more and more obsolete nowadays and only the MSW port is still using a native palette. All other ports use generic code which is basically just an array of colours.

It is likely that in the future the only use for palettes within wxWidgets will be for representing colour indeces from images (such as GIF or PNG). The image handlers for these formats have been modified to create a palette if there is such information in the original image file (usually 256 or less colour images). See wxImage for more information.

Library:  wxCore

Category:  Graphics Device Interface (GDI)

Predefined objects/pointers: wxNullPalette

See also:

wxDC::SetPalette(), wxBitmap

Public Member Functions
	wxPalette ()
	wxPalette (const wxPalette &palette)
	wxPalette (int n, const unsigned char *red, const unsigned char *green, const unsigned char *blue)
virtual	~wxPalette ()
bool	Create (int n, const unsigned char *red, const unsigned char *green, const unsigned char *blue)
virtual int	GetColoursCount () const
int	GetPixel (unsigned char red, unsigned char green, unsigned char blue) const
bool	GetRGB (int pixel, unsigned char *red, unsigned char *green, unsigned char *blue) const
virtual bool	IsOk () const
wxPalette &	operator= (const wxPalette &palette)

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Constructor & Destructor Documentation

wxPalette::wxPalette

(

)

Default constructor.

wxPalette::wxPalette

(

const wxPalette &

palette

)

Copy constructor, uses Reference Counting.

Parameters:

palette

A reference to the palette to copy.

wxPalette::wxPalette	(	int	n,
		const unsigned char *	red,
		const unsigned char *	green,
		const unsigned char *	blue
	)

Creates a palette from arrays of size n, one for each red, blue or green component.

Parameters:

	n	The number of indices in the palette.
	red	An array of red values.
	green	An array of green values.
	blue	An array of blue values.

See also:

Create()

virtual wxPalette::~wxPalette

(

)

[virtual]

Destructor.

See also:

reference-counted object destruction

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Member Function Documentation

bool wxPalette::Create	(	int	n,
		const unsigned char *	red,
		const unsigned char *	green,
		const unsigned char *	blue
	)

Creates a palette from arrays of size n, one for each red, blue or green component.

Parameters:

	n	The number of indices in the palette.
	red	An array of red values.
	green	An array of green values.
	blue	An array of blue values.

Returns:

true if the creation was successful, false otherwise.

See also:

wxPalette()

virtual int wxPalette::GetColoursCount

(

)

const [virtual]

Returns number of entries in palette.

int wxPalette::GetPixel	(	unsigned char	red,
		unsigned char	green,
		unsigned char	blue
	)			const

Returns a pixel value (index into the palette) for the given RGB values.

Parameters:

	red	Red value.
	green	Green value.
	blue	Blue value.

Returns:

The nearest palette index or wxNOT_FOUND for unexpected errors.

See also:

GetRGB()

bool wxPalette::GetRGB	(	int	pixel,
		unsigned char *	red,
		unsigned char *	green,
		unsigned char *	blue
	)			const

Returns RGB values for a given palette index.

Parameters:

	pixel	The palette index.
	red	Receives the red value.
	green	Receives the green value.
	blue	Receives the blue value.

Returns:

true if the operation was successful.

See also:

GetPixel()

virtual bool wxPalette::IsOk

(

)

const [virtual]

Returns true if palette data is present.

wxPalette& wxPalette::operator=

(

const wxPalette &

palette

)

Assignment operator, using Reference Counting.