view docs/man3/SDL_SetGammaRamp.3 @ 370:ba72f259bc88

Date: Sat, 18 May 2002 17:40:53 +0300 From: Mike Gorchak <mike@malva.ua> Subject: New QNX patches - Added more error check to avoid SEGFAULTS; - Fixed bug in update function for SDL_HWSURFACE. BTW: update is much faster than before. - Added checks for SDL_HWSURFACE flag, chosen bpp must be equal to desktop bpp for SDL_HWSURFACE. - Fixed overlay bug, no more SEGFAULTS.
author Sam Lantinga <slouken@libsdl.org>
date Sun, 19 May 2002 19:54:01 +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