view docs/html/sdlmaprgb.html @ 998:0e6627072f7a

Date: Wed, 24 Nov 2004 01:25:48 +0100 From: Stephane Marchesin Subject: Re: [SDL] Problem compiling SDL 1.2.7 - there is a bug that was introduced in the kernel headers for 2.6.9 which is fixed in 2.6.10. This bug *will* byte when compiling the cdrom subsystem. A patch that works around this bug is attached. Note that users affected are not those running 2.6.9, but those using the 2.6.9 kernel headers for their system (i.e. whose libc is built against 2.6.9 headers).
author Sam Lantinga <slouken@libsdl.org>
date Tue, 30 Nov 2004 14:45:08 +0000
parents 355632dca928
children
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>SDL_MapRGB</TITLE
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><H1
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>SDL_MapRGB</H1
><DIV
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><A
NAME="AEN1652"
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><H2
>Name</H2
>SDL_MapRGB&nbsp;--&nbsp;Map a RGB color value to a pixel format.</DIV
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><H2
>Synopsis</H2
><DIV
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><P
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><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>Uint32 <B
CLASS="FSFUNC"
>SDL_MapRGB</B
></CODE
>(SDL_PixelFormat *fmt, Uint8 r, Uint8 g, Uint8 b);</CODE
></P
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><A
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><H2
>Description</H2
><P
>Maps the RGB 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 an alpha component it will be returned
as all 1 bits (fully opaque).</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN1667"
></A
><H2
>Return Value</H2
><P
>A pixel value best approximating the given RGB 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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><H2
>See Also</H2
><P
><A
HREF="sdlgetrgb.html"
><TT
CLASS="FUNCTION"
>SDL_GetRGB</TT
></A
>,
<A
HREF="sdlgetrgba.html"
><TT
CLASS="FUNCTION"
>SDL_GetRGBA</TT
></A
>,
<A
HREF="sdlmaprgba.html"
><TT
CLASS="FUNCTION"
>SDL_MapRGBA</TT
></A
>,
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HREF="sdlpixelformat.html"
><SPAN
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>SDL_PixelFormat</SPAN
></A
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