view docs/man3/SDL_SetGammaRamp.3 @ 2226:0e70b4b8cf84

Date: Sat, 11 Aug 2007 02:03:16 +0200 (CEST) From: couriersud arcor.de To: slouken@libsdl.org Subject: Directfb driver for SDL1.3 Hi, the attachment contains a patch for a SDL1.3 directfb driver. It supports: - Renderer "directfb": Hardware acceleration as supported by the underlying directfb driver. With a radeon X850, testsprite2 runs at 50% to 70% of OpenGL (X11, dri) performance. Also supports hardware accelerated yuv overlays. This must be enabled by sett ing: export SDL_DIRECTFB_YUV_DIRECT=1 - Renderer "opengl" Supports software opengl using mesa opengl (make linux-directfb). Some more information may be found in README.DirectFB There will certainly still be some bugs, and there is some debug code around. When I find some time, I will compile against directfb-0.9.25 as distributed with ubuntu 7.04. The diff also contains a fix for SDL_LockYUVOverlay fixing a bug in *pixels and pitches initialization. Kind regards, couriersud
author Sam Lantinga <slouken@libsdl.org>
date Sat, 11 Aug 2007 21:51:19 +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