Loading Animated GIFs with SDL_Image

1#include <SDL.h>
2#include <SDL_image.h>
3
4#include <iostream>
5
6int main() {
7  SDL_Init(SDL_INIT_VIDEO);
8  IMG_Init(IMG_INIT_GIF);
9
10  SDL_Window* window =
11    SDL_CreateWindow("Animated GIF Example",
12                     SDL_WINDOWPOS_UNDEFINED,
13                     SDL_WINDOWPOS_UNDEFINED,
14                     640, 480, 0);
15  SDL_Renderer* renderer = SDL_CreateRenderer(
16    window, -1, 0);
17
18  SDL_Surface* gifSurface = IMG_Load(
19    "animation.gif");
20  if (!gifSurface) {
21    std::cout << "Failed to load GIF: " <<
22      IMG_GetError() << '\n';
23    return 1;
24  }
25
26  SDL_Texture* gifTexture =
27    SDL_CreateTextureFromSurface(
28      renderer, gifSurface);
29  SDL_FreeSurface(gifSurface);
30
31  // ... (rest of the code)
32}

1int main() {
2  // ... (previous code)
3
4  int frameWidth = gifSurface->w;
5  int frameHeight = gifSurface->h;
6  // Assuming horizontal strip
7  int totalFrames = gifSurface->w / frameWidth;
8  int currentFrame = 0;
9
10  // Milliseconds between frames
11  int frameDelay = 100;
12
13  Uint32 frameStart = SDL_GetTicks();
14
15  bool quit = false;
16  SDL_Event event;
17
18  while (!quit) {
19    while (SDL_PollEvent(&event)) {
20      if (event.type == SDL_QUIT) {
21        quit = true;
22      }
23    }
24
25    Uint32 currentTime = SDL_GetTicks();
26    if (currentTime - frameStart >=
27      frameDelay) {
28      currentFrame = (currentFrame + 1) %
29        totalFrames;
30      frameStart = currentTime;
31    }
32
33    SDL_Rect srcRect = {
34      currentFrame * frameWidth, 0, frameWidth,
35      frameHeight};
36    // Adjust as needed
37    SDL_Rect dstRect = {0, 0, 640, 480};
38
39    SDL_RenderClear(renderer);
40    SDL_RenderCopy(renderer, gifTexture,
41                   &srcRect, &dstRect);
42    SDL_RenderPresent(renderer);
43  }
44
45  SDL_DestroyTexture(gifTexture);
46  SDL_DestroyRenderer(renderer);
47  SDL_DestroyWindow(window);
48  IMG_Quit();
49  SDL_Quit();
50
51  return 0;
52}