view docs/man3/SDL_SetGammaRamp.3 @ 604:31d3af76488b

Date: Mon, 24 Feb 2003 16:31:25 -0500 From: Ragnvald "Despair" Maartmann-Moe IV Subject: SDL x11 video mode selection bug Hi, I've found an oddity with video mode selection. I recently added a bunch of oddball video modes to my XF86Config, to support weird resolutions xine & mplayer need if I don't want to beat my cpu up with video scaling. Since adding them, SDL started picking the biggest video mode it could find that matched the height constraint. Getting a narrow vertical strip of QuakeForge (I code for the project, so needless to say it's my favorite test) in the middle of an 800x480 screen, instead of the 640x480 I asked for annoys me tremendously. So here's a patch that tries a bit harder to get an exact match. I didn't touch the XiG section, since I can't test that, but I'd bet a similar patch would prevent similar problems there. --Ragnvald "Despair" Maartmann-Moe IV
author Sam Lantinga <slouken@libsdl.org>
date Thu, 06 Mar 2003 06:02:16 +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