| 1 | .TH "SDL_SetGammaRamp" "3" "Tue 11 Sep 2001, 23:01" "SDL" "SDL API Reference" |
| 2 | .SH "NAME" |
| 3 | SDL_SetGammaRamp \- Sets the color gamma lookup tables for the display |
| 4 | .SH "SYNOPSIS" |
| 5 | .PP |
| 6 | \fB#include "SDL\&.h" |
| 7 | .sp |
| 8 | \fBint \fBSDL_SetGammaRamp\fP\fR(\fBUint16 *redtable, Uint16 *greentable, Uint16 *bluetable\fR); |
| 9 | .SH "DESCRIPTION" |
| 10 | .PP |
| 11 | 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\&. |
| 12 | .PP |
| 13 | 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\&. |
| 14 | .PP |
| 15 | Not all display hardware is able to change gamma\&. |
| 16 | .SH "RETURN VALUE" |
| 17 | .PP |
| 18 | Returns -1 on error (or if gamma adjustment is not supported)\&. |
| 19 | .SH "SEE ALSO" |
| 20 | .PP |
| 21 | \fISDL_SetGamma\fR \fISDL_GetGammaRamp\fR |
| 22 | .\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:01 |