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copied!<p>If all you want to do is display the data (ie no need for a GUI), you might want to take a look at <a href="http://www.libsdl.org" rel="nofollow noreferrer">SDL</a>: It's straight-forward to <a href="http://www.libsdl.org/cgi/docwiki.fcg/SDL_CreateRGBSurfaceFrom" rel="nofollow noreferrer">create a surface from your pixel data</a> and then <a href="http://www.libsdl.org/cgi/docwiki.fcg/SDL_BlitSurface" rel="nofollow noreferrer">display it on screen</a>.</p> <p>Inspired by <a href="https://stackoverflow.com/questions/1391314/easy-way-to-display-a-continuously-updating-image-in-c-linux/1391406#1391406">Artelius' answer</a>, I also hacked up an example program:</p> <pre><code>#include <SDL/SDL.h> #include <assert.h> #include <stdint.h> #include <stdlib.h> #define WIDTH 256 #define HEIGHT 256 static _Bool init_app(const char * name, SDL_Surface * icon, uint32_t flags) { atexit(SDL_Quit); if(SDL_Init(flags) < 0) return 0; SDL_WM_SetCaption(name, name); SDL_WM_SetIcon(icon, NULL); return 1; } static uint8_t * init_data(uint8_t * data) { for(size_t i = WIDTH * HEIGHT * 3; i--; ) data[i] = (i % 3 == 0) ? (i / 3) % WIDTH : (i % 3 == 1) ? (i / 3) / WIDTH : 0; return data; } static _Bool process(uint8_t * data) { for(SDL_Event event; SDL_PollEvent(&event);) if(event.type == SDL_QUIT) return 0; for(size_t i = 0; i < WIDTH * HEIGHT * 3; i += 1 + rand() % 3) data[i] -= rand() % 8; return 1; } static void render(SDL_Surface * sf) { SDL_Surface * screen = SDL_GetVideoSurface(); if(SDL_BlitSurface(sf, NULL, screen, NULL) == 0) SDL_UpdateRect(screen, 0, 0, 0, 0); } static int filter(const SDL_Event * event) { return event->type == SDL_QUIT; } #define mask32(BYTE) (*(uint32_t *)(uint8_t [4]){ [BYTE] = 0xff }) int main(int argc, char * argv[]) { (void)argc, (void)argv; static uint8_t buffer[WIDTH * HEIGHT * 3]; _Bool ok = init_app("SDL example", NULL, SDL_INIT_VIDEO) && SDL_SetVideoMode(WIDTH, HEIGHT, 24, SDL_HWSURFACE); assert(ok); SDL_Surface * data_sf = SDL_CreateRGBSurfaceFrom( init_data(buffer), WIDTH, HEIGHT, 24, WIDTH * 3, mask32(0), mask32(1), mask32(2), 0); SDL_SetEventFilter(filter); for(; process(buffer); SDL_Delay(10)) render(data_sf); return 0; } </code></pre>

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