SDL_MapRGBA

Use this function to map an RGBA quadruple to a pixel value for a given pixel format.

Syntax

Uint32 SDL_MapRGBA(const SDL_PixelFormat* format,
                   Uint8                  r, 
                   Uint8                  g, 
                   Uint8                  b,
                   Uint8                  a)

Function Parameters

format

an SDL_PixelFormat structure describing the format of the pixel

r

the red component of the pixel in the range 0-255

g

the green component of the pixel in the range 0-255

b

the blue component of the pixel in the range 0-255

a

the alpha component of the pixel in the range 0-255

Return Value

A *32-bit* pixel value.

If the format has a palette (8-bit) the index of the closest matching color in the palette will be returned.

Code Examples

You can add your code example here

Remarks

*
If the specified pixel format has no alpha component the alpha value will be ignored (as it will be in formats with a palette).

If the pixel format bpp (color depth) is less than 32-bpp then the unused upper bits of the return value can safely be ignored (e.g., with a 16-bpp format the return value can be assigned to a Uint16, and similarly a Uint8 for an 8-bpp format).
*


CategoryAPI, CategoryPixels

SDL_MapRGBA (last edited 2010-08-08 05:24:18 by SheenaSmith)