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Date: Sun, 29 Feb 2004 15:14:22 +0200 From: Martin_Storsj Subject: Dynamic loading of ALSA I recently discovered that SDL can dynamically load ESD and aRts, and made a patch which adds this same functionality to ALSA. The update for configure.in isn't too good (it should e.g. look for libasound.so in other directories than /usr/lib), because I'm not too good at shellscripting and autoconf. The reason for using dlfcn.h and dlopen instead of SDL_LoadLibrary and SDL_LoadFunction is that libasound uses versioned symbols, and it is necessary to load the correct version using dlvsym. This isn't probably any real portability issue, because ALSA is linux-only.
author Sam Lantinga <slouken@libsdl.org>
date Tue, 02 Mar 2004 12:49:16 +0000
parents e5bc29de3f0a
children 546f7c1eb755
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.TH "SDL_SetGammaRamp" "3" "Tue 11 Sep 2001, 23:01" "SDL" "SDL API Reference" 
.SH "NAME"
SDL_SetGammaRamp\- Sets the color gamma lookup tables for the display
.SH "SYNOPSIS"
.PP
\fB#include "SDL\&.h"
.sp
\fBint \fBSDL_SetGammaRamp\fP\fR(\fBUint16 *redtable, Uint16 *greentable, Uint16 *bluetable\fR);
.SH "DESCRIPTION"
.PP
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\&.
.PP
This function adjusts the gamma based on lookup tables, you can also have the gamma calculated based on a "gamma function" parameter with \fISDL_SetGamma\fR\&.
.PP
Not all display hardware is able to change gamma\&.
.SH "RETURN VALUE"
.PP
Returns -1 on error (or if gamma adjustment is not supported)\&.
.SH "SEE ALSO"
.PP
\fISDL_SetGamma\fR \fISDL_GetGammaRamp\fR
...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:01