view docs/man3/SDL_SetGammaRamp.3 @ 672:5955fa16d4b8

Date: Mon, 28 Jul 2003 18:30:50 +0300 From: "Mike Gorchak" Subject: New test for overlays While writting QNX Photon Overlay code I've found that the existent overlay test application is not enough, it performs too artificial tests - it always moves/resizes the overlay's viewport, but in the real life that happens very rare. So I decided to write new test (commonly base on testoverlay.c code) and called it testoverlay2 :) moose.dat - raw 8 bit paletted data of the small movie. (It was a moose.gif, also included in the attachment as reference, but not needed for this test, it is just for information). I cannot find, who created this .gif, so no credits this time :) But over inet I saw this gif zillion times, so I think we do not infringing somebody rights :)
author Sam Lantinga <slouken@libsdl.org>
date Fri, 08 Aug 2003 21:31:18 +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