view docs/man3/SDL_SetGammaRamp.3 @ 2866:e532417a6977

Fixed SDL 1.2 compatibility problem. The API specifies that SDL_OpenAudio() will fill out the 'desired' audio spec with the correct samples and size set by the driver. This value is important since it may be used by applications that size audio buffers, etc. However, we want to allow advanced applications to call SDL_OpenAudioDevice() which gets passed a const 'desired' parameter, and have the correct data filled into the 'obtained' parameter, possibly allowing or not allowing format changes. So... 'obtained' becomes the audio format the user callback is expected to use, and we add flags to allow the application to specify which format changes are allowed. Note: We really need to add a way to query the 'obtained' audio spec.
author Sam Lantinga <slouken@libsdl.org>
date Sat, 13 Dec 2008 06:36:47 +0000
parents 546f7c1eb755
children 1238da4a7112
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