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Returns 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.
Returns a pixel value; see [[#Remarks|Remarks]] for details.
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*<<BR>>If the specified pixel format has no alpha component the alpha value will be ignored (as it will be in formats with a palette). <<BR>>* If the specified pixel format has no alpha component the alpha value will be ignored (as it will be in formats with a palette).
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If the specified pixel format has an alpha component it will be returned as all 1 bits (fully opaque).

DRAFT

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

Returns a pixel value; see Remarks for details.

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).

This function maps the RGB color value to the specified pixel format and returns the pixel value best approximating the given RGB color value for the given pixel format.

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

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

None: SDL_MapRGBA (last edited 2010-09-26 17:32:32 by SheenaSmith)

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