view docs/man3/SDL_SetGammaRamp.3 @ 720:f90d80d68071

N Sep 17 8791 Sam Lantinga Re: tks source released Date: Sun, 07 Sep 2003 02:51:58 +0200 From: Stephane Marchesin Subject: [SDL] Two little patches Compiling SDL with a recent gcc (gcc 3.3.1, 3.3 doesn't have this behaviour) gives some nasty warnings : SDL_blit_A.c: In function `BlitRGBtoRGBSurfaceAlpha128MMX': SDL_blit_A.c:223: warning: integer constant is too large for "long" type SDL_blit_A.c:225: warning: integer constant is too large for "long" type SDL_blit_A.c:227: warning: integer constant is too large for "long" type [...] The first attached patch (longlongfix.patch) tells gcc to really treat those constants as unsigned long long and not long. The second patch (nasinclude.patch) fixes an include problem I had while compiling nas audio : when the <audio/audiolib.h> file lies in /usr/X11R6/include, a -I/usr/X11R6/include option is needed or the file isn't found.
author Sam Lantinga <slouken@libsdl.org>
date Sun, 21 Sep 2003 18:32:04 +0000
parents e5bc29de3f0a
children 546f7c1eb755
line wrap: on
line source

.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