view docs/man3/SDL_SetGammaRamp.3 @ 1754:c67921b517c3

Date: Sun, 30 Apr 2006 14:20:05 +1000 From: Rob Subject: [SDL] SDL pre-release OpenGL fails on the zipped pre-release source accessible from http://www.libsdl.org/svn.php. Appears to be following lines in sdl_wing.c (lines 341-345): wglext = (const char *)this->glGetString(GL_EXTENSIONS); if ( !SDL_strstr(wglext, "WGL_EXT_swap_control") ) { this->gl_data->wglSwapIntervalEXT = NULL; this->gl_data->wglGetSwapIntervalEXT = NULL; } glGetString is a null pointer, as are other gl function pointers, so call fails. Never looked at sdl source before, so no further than that as yet.
author Sam Lantinga <slouken@libsdl.org>
date Mon, 01 May 2006 07:15:35 +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