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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_SetGamma</TITLE
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><H1
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>SDL_SetGamma</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN1569"
></A
><H2
>Name</H2
>SDL_SetGamma&nbsp;--&nbsp;Sets the color gamma function for the display</DIV
><DIV
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><H2
>Synopsis</H2
><DIV
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><P
></P
><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>int <B
CLASS="FSFUNC"
>SDL_SetGamma</B
></CODE
>(float redgamma, float greengamma, float bluegamma);</CODE
></P
><P
></P
></DIV
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><DIV
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><A
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></A
><H2
>Description</H2
><P
>Sets the "gamma function" for the display of each color component.  Gamma
controls the brightness/contrast of colors displayed on the screen.
A gamma value of <TT
CLASS="CONSTANT"
>1.0</TT
> is identity (i.e., no adjustment
is made).</P
><P
>This function adjusts the gamma based on the "gamma function" parameter,
you can directly specify lookup tables for gamma adjustment with
<A
HREF="sdlsetgammaramp.html"
>SDL_SetGammaRamp</A
>.</P
><P
>Not all display hardware is able to change gamma.</P
></DIV
><DIV
CLASS="REFSECT1"
><A
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></A
><H2
>Return Value</H2
><P
>Returns -1 on error (or if gamma adjustment is not supported).</P
></DIV
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></A
><H2
>See Also</H2
><P
><A
HREF="sdlgetgammaramp.html"
>SDL_GetGammaRamp</A
>
<A
HREF="sdlsetgammaramp.html"
>SDL_SetGammaRamp</A
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