wxErlang

Reference Manual

Version 2.0

Table of Contents

wxPalette

Module

wxPalette

Module Summary

Functions for wxPalette class

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 indices 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.

Predefined objects/pointers: ?wxNullPalette

See: wxDC:setPalette/2, wxBitmap

wxWidgets docs: wxPalette

new() -> wxPalette()

Default constructor.

new(Palette) -> wxPalette()

Types

Palette = wxPalette()

Copy constructor, uses overview_refcount.

new(Red, Green, Blue) -> wxPalette()

Types

Red = Green = Blue = binary()

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

See: create/4

destroy(This :: wxPalette()) -> ok

Destructor.

See: reference-counted object destruction

create(This, Red, Green, Blue) -> boolean()

Types

Red = Green = Blue = binary()

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

Return: true if the creation was successful, false otherwise.

See: new/3

getColoursCount(This) -> integer()

Types

Returns number of entries in palette.

getPixel(This, Red, Green, Blue) -> integer()

Types

Red = Green = Blue = integer()

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

Return: The nearest palette index or wxNOT_FOUND for unexpected errors.

See: getRGB/2

getRGB(This, Pixel) -> Result

Types

Result =
    {Res :: boolean(),
     Red :: integer(),
     Green :: integer(),
     Blue :: integer()}
Pixel = integer()

Returns RGB values for a given palette index.

Return: true if the operation was successful.

See: getPixel/4

ok(This) -> boolean()

Types

See: isOk/1.

isOk(This) -> boolean()

Types

Returns true if palette data is present.