view docs/html/sdlsetgammaramp.html @ 4347:38f22ed3a433 SDL-1.2

Option to fix bug #851 For some people setting the period size works better (and is what SDL 1.2.13 did), but for most people it's the same or worse. You can use an environment variable to pick which one you want.
author Sam Lantinga <slouken@libsdl.org>
date Sat, 17 Oct 2009 06:55:17 +0000
parents 355632dca928
children
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><H1
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>SDL_SetGammaRamp</H1
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><H2
>Name</H2
>SDL_SetGammaRamp&nbsp;--&nbsp;Sets the color gamma lookup tables for the display</DIV
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>Synopsis</H2
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><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>int <B
CLASS="FSFUNC"
>SDL_SetGammaRamp</B
></CODE
>(Uint16 *redtable, Uint16 *greentable, Uint16 *bluetable);</CODE
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>Description</H2
><P
>Sets the gamma lookup tables for the display for each color component.
Each table is an array of 256 Uint16 values, representing a mapping
between the input and output for that channel. The input is the index
into the array, and the output is the 16-bit gamma value at that index,
scaled to the output color precision. You may pass NULL to any of the
channels to leave them unchanged.</P
><P
>This function adjusts the gamma based on lookup tables, you can also
have the gamma calculated based on a "gamma function" parameter with
<A
HREF="sdlsetgamma.html"
>SDL_SetGamma</A
>.</P
><P
>Not all display hardware is able to change gamma.</P
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>Return Value</H2
><P
>Returns -1 on error (or if gamma adjustment is not supported).</P
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>See Also</H2
><P
><A
HREF="sdlsetgamma.html"
>SDL_SetGamma</A
>
<A
HREF="sdlgetgammaramp.html"
>SDL_GetGammaRamp</A
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