view docs/html/sdlmaprgba.html @ 3261:72b542f34739

The new, cleaner, version of the atomic operations. The dummy code is what you should start working with to port atomic ops. The linux code appears to be complete and *should* be the base of all Unix and GCC based versions. The macosx and win32 versions are currently just copies of the dummy code. I will begin working on the windows version as soon as this check in is done. I need someone to work on the Mac OS X version. I'm afraid that this check in will break QNX (Sorry!)
author Bob Pendleton <bob@pendleton.com>
date Thu, 17 Sep 2009 20:35:12 +0000
parents 355632dca928
children
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>SDL_MapRGBA</H1
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><H2
>Name</H2
>SDL_MapRGBA&nbsp;--&nbsp;Map a RGBA color value to a pixel format.</DIV
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>Synopsis</H2
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><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>Uint32 <B
CLASS="FSFUNC"
>SDL_MapRGBA</B
></CODE
>(SDL_PixelFormat *fmt, Uint8 r, Uint8 g, Uint8 b, Uint8 a);</CODE
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><H2
>Description</H2
><P
>Maps the RGBA color value to the specified pixel format and returns the
pixel value as a 32-bit int.</P
><P
>If the format has a palette (8-bit) the index of the closest matching
color in the palette will be returned.</P
><P
>If the specified pixel format has no alpha component the alpha value
will be ignored (as it will be in formats with a palette).</P
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CLASS="REFSECT1"
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NAME="AEN1702"
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><H2
>Return Value</H2
><P
>A pixel value best approximating the given RGBA color value for a given
pixel format. 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
<SPAN
CLASS="TYPE"
>Uint16</SPAN
>, and similarly a <SPAN
CLASS="TYPE"
>Uint8</SPAN
> for an 8-bpp
format).</P
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>See Also</H2
><P
><A
HREF="sdlgetrgb.html"
>SDL_GetRGB</A
>,
<A
HREF="sdlgetrgba.html"
>SDL_GetRGBA</A
>,
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HREF="sdlmaprgb.html"
>SDL_MapRGB</A
>,
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>SDL_PixelFormat</A
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