comparison src/video/SDL_pixels.c @ 997:3bf4103b2b89

Date: Sat, 27 Nov 2004 13:35:43 +0100 From: "Martin Bickel" Subject: [SDL] Patch: fixing uninitilized palette while running Valgrind over my application I found the following problem in SDL: The function MapNto1 allocates SDL_Color colors[256] but does not initialize it. SDL_DitherColors is then called which initialized the r, g and b component, but not the 'unused' component of each color. When Map1to1 is called from MapNto1, it runs a memcmp on the colors, which also evaluates the unused component and therefor returns differences much more often than necessary. So the 'unused' component of SDL_Color should be initialized. This patch does this by calling memset for the whole array in MapNto1 .
author Sam Lantinga <slouken@libsdl.org>
date Tue, 30 Nov 2004 14:28:20 +0000
parents 333db1d87876
children c69697a85412
comparison
equal deleted inserted replaced
996:54bb19455081 997:3bf4103b2b89
492 static Uint8 *MapNto1(SDL_PixelFormat *src, SDL_Palette *dst, int *identical) 492 static Uint8 *MapNto1(SDL_PixelFormat *src, SDL_Palette *dst, int *identical)
493 { 493 {
494 /* Generate a 256 color dither palette */ 494 /* Generate a 256 color dither palette */
495 SDL_Palette dithered; 495 SDL_Palette dithered;
496 SDL_Color colors[256]; 496 SDL_Color colors[256];
497
498 /* SDL_DitherColors does not initialize the 'unused' component of colors,
499 but Map1to1 compares it against dst, so we should initialize it. */
500 memset(colors, 0, sizeof(colors));
497 501
498 dithered.ncolors = 256; 502 dithered.ncolors = 256;
499 SDL_DitherColors(colors, 8); 503 SDL_DitherColors(colors, 8);
500 dithered.colors = colors; 504 dithered.colors = colors;
501 return(Map1to1(&dithered, dst, identical)); 505 return(Map1to1(&dithered, dst, identical));