view docs/html/sdlsetgammaramp.html @ 1078:e2ef6b7001fd

Patch from Antonio SJ Musumeci: " This code with SDL-1.2.8 and CVS: #include <stdio.h> #include <stdlib.h> #include <SDL.h> int main(int argc, char** argv) { char alphabet[26] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"; char buffer_file[27] = {0}; char buffer_mem[27] = {0}; int rv_file; int rv_mem; FILE* file_ptr; SDL_RWops* rwop_file; SDL_RWops* rwop_mem; file_ptr = fopen("./blah", "w"); fwrite(alphabet, 1, sizeof(alphabet), file_ptr); fclose(file_ptr); rwop_mem = SDL_RWFromMem(alphabet, sizeof(alphabet)); rwop_file = SDL_RWFromFile("./blah", "r"); rv_mem = SDL_RWread(rwop_mem , buffer_mem, 5, 6); rv_file = SDL_RWread(rwop_file, buffer_file, 5, 6); printf("From File: %d %s\n" "From Mem: %d %s\n", rv_file, buffer_file, rv_mem, buffer_mem); printf("Seek end of File: %d\n" "Seek end of Mem: %d\n", SDL_RWseek(rwop_file, 0, SEEK_END), SDL_RWseek(rwop_mem , 0, SEEK_END)); SDL_RWclose(rwop_file); SDL_RWclose(rwop_mem); return 0; } Produces this output: From File: 5 ABCDEFGHIJKLMNOPQRSTUVWXYZ From Mem: 5 ABCDEFGHIJKLMNOPQRSTUVWXY Seek end of File: 26 Seek end of Mem: 26 " --ryan.
author Ryan C. Gordon <icculus@icculus.org>
date Fri, 24 Jun 2005 12:48:38 +0000
parents 355632dca928
children
line wrap: on
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><H1
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>SDL_SetGammaRamp</H1
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><A
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><H2
>Name</H2
>SDL_SetGammaRamp&nbsp;--&nbsp;Sets the color gamma lookup tables for the display</DIV
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><PRE
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>#include "SDL.h"</PRE
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><CODE
><CODE
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>int <B
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>SDL_SetGammaRamp</B
></CODE
>(Uint16 *redtable, Uint16 *greentable, Uint16 *bluetable);</CODE
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>Description</H2
><P
>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.</P
><P
>This function adjusts the gamma based on lookup tables, you can also
have the gamma calculated based on a "gamma function" parameter with
<A
HREF="sdlsetgamma.html"
>SDL_SetGamma</A
>.</P
><P
>Not all display hardware is able to change gamma.</P
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>Return Value</H2
><P
>Returns -1 on error (or if gamma adjustment is not supported).</P
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>See Also</H2
><P
><A
HREF="sdlsetgamma.html"
>SDL_SetGamma</A
>
<A
HREF="sdlgetgammaramp.html"
>SDL_GetGammaRamp</A
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