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Date: Tue, 9 May 2006 23:01:49 -0400 From: Mike Frysinger Subject: [SDL] [patch] fall back to using MAP_PRIVATE with mmap() in fbcon dri trying to use MAP_SHARED with mmap() on uClinux (aka non-mmu) hosts nowadays will simply fail since the kernel disallows it ... falling back to using MAP_PRIVATE on these hosts is acceptable ... as such, ive attached a patch for the fbcon driver that will fall back to using MAP_PRIVATE if mmap() with MAP_SHARED failed going by a grep of MAP_SHARED, the only other drivers that utilize this flag are video/wscons, video/ps2gs, and sound/dmaaudio ... i dont think these would appear on a non-mmu host so the patch i wrote is restricted to just SDL_fbvideo.c ... -mike
author Sam Lantinga <slouken@libsdl.org>
date Wed, 10 May 2006 04:05:46 +0000
parents 355632dca928
children
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<HTML
><HEAD
><TITLE
>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
CLASS="REFSYNOPSISDIV"
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><H2
>Synopsis</H2
><DIV
CLASS="FUNCSYNOPSIS"
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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
NAME="AEN1579"
></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
NAME="AEN1586"
></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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