TODO: GIF対応

Makefile

@@ -5,7 +5,7 @@ PREFIX=/usr/local
 CC=cc
 FILES=main.c
 CFLAGS=-Wall -Wextra -g
-LIBS=-lSDL2 -lSDL2_image -lcurl
+LIBS=-lSDL2 -lSDL2_image -lcurl -lgif
 LDFLAGS=-L${PREFIX}/lib
 CPPFLAGS=-I${PREFIX}/include
 

README.md

@@ -5,49 +5,49 @@
 
 ## OpenBSD
 ```sh
-doas pkg_add sdl2 sdl2_image curl
+doas pkg_add sdl2 sdl2_image curl giflib
 make
 doas make install
 ```
 
 ## FreeBSD
 ```sh
-doas pkg install sdl2 sdl2_image curl
+doas pkg install sdl2 sdl2_image curl giflib
 make
 doas make install
 ```
 
 ## NetBSD
 ```sh
-doas pkgin install SDL2-2.28.5 SDL2_image curl
+doas pkgin install SDL2-2.28.5 SDL2_image curl giflib
 make PREFIX=/usr/pkg
 doas make install PREFIX=/usr/pkg
 ```
 
 ## CRUX
 ```sh
-doas prt-get depinst libsdl2 sdl2_image curl
+doas prt-get depinst libsdl2 sdl2_image curl giflib
 make PREFIX=/usr
 doas make install PREFIX=/usr
 ```
 
 ## Void Linux
 ```sh
-doas xbps-install -S SDL2 SDL2_image curl
+doas xbps-install -S SDL2 SDL2_image curl giflib-devel
 make PREFIX=/usr
 doas make install PREFIX=/usr
 ```
 
 ## Artix Linux
 ```sh
-doas pacman -S sdl2 sdl2_image curl
+doas pacman -S sdl2 sdl2_image curl giflib
 make PREFIX=/usr
 doas make install PREFIX=/usr
 ```
 
 ## Devuan GNU/Linux
 ```sh
-doas apt install libsdl2-dev libsdl2-image-dev libcurl4
+doas apt install libsdl2-dev libsdl2-image-dev libcurl4 giflib-tools
 make PREFIX=/usr
 doas make install PREFIX=/usr
 ```

main.c

@@ -3,6 +3,7 @@
 #include <stdio.h>
 #include <stdbool.h>
 #include <curl/curl.h>
+#include <gif_lib.h>
 
 #define DELAY_MS 50
 
@@ -10,6 +11,7 @@ SDL_Window* window = NULL;
 SDL_Renderer* renderer = NULL;
 SDL_Texture* texture = NULL;
 bool quit = false;
+GifFileType* gif = NULL;
 
 bool dlfile(const char* url, const char* filename) {
   CURL* curl = curl_easy_init();
@@ -35,6 +37,58 @@ bool dlfile(const char* url, const char* filename) {
   return true;
 }
 
+const char* getmime(const char *filename) {
+  FILE* file = fopen(filename, "rb");
+  if (!file) {
+    fprintf(stderr, "ファイルを開くに失敗: %s\n", filename);
+    return NULL;
+  }
+
+  char header[4];
+  fread(header, sizeof(char), 4, file);
+  fclose(file);
+
+  if (header[0] == 'G' && header[1] == 'I' && header[2] == 'F' && header[3] == '8') {
+    return "image/gif";
+  }
+
+  return "image/png";
+}
+
+SDL_Surface* loadgif(const char* filename) {
+  int error;
+  gif = DGifOpenFileName(filename, &error);
+  if (!gif) {
+    fprintf(stderr, "GIFファイルを開くに失敗: %s\n", filename);
+    return NULL;
+  }
+
+  error = DGifSlurp(gif);
+  if (error != GIF_OK) {
+    fprintf(stderr, "GIFファイルの読込に失敗: %s\n", GifErrorString(error));
+    DGifCloseFile(gif, &error);
+    return NULL;
+  }
+
+  SavedImage* frame = &(gif->SavedImages[0]);
+  SDL_Surface* surface = SDL_CreateRGBSurface(
+      0,
+      frame->ImageDesc.Width,
+      frame->ImageDesc.Height,
+      24,
+      0, 0, 0, 0
+  );
+  /* SDL_Surface* surface = SDL_CreateRGBSurfaceFrom((void*)frame->RasterBits, */
+  /*     frame->ImageDesc.Width, */
+  /*     frame->ImageDesc.Height, */
+  /*     8 * sizeof(GifPixelType), */
+  /*     frame->ImageDesc.Width * sizeof(GifPixelType), */
+  /*     0xFF, 0xFF00, 0xFF0000, 0); */
+  DGifCloseFile(gif, &error);
+
+  return surface;
+}
+
 void windowevent(SDL_Event e) {
   if (e.type == SDL_QUIT) {
     quit = true;
@@ -58,7 +112,12 @@ void windowevent(SDL_Event e) {
     /* } */
 
     // テキスチャーのれんダーリングサイズの設定
-    SDL_Rect renderQuad = { (newWidth - scaledWidth) / 2, (newHeight - scaledHeight) / 2, scaledWidth, scaledHeight };
+    SDL_Rect renderQuad = {
+      (newWidth - scaledWidth) / 2,
+      (newHeight - scaledHeight) / 2,
+      scaledWidth,
+      scaledHeight
+    };
     SDL_RenderCopy(renderer, texture, NULL, &renderQuad);
   } else if (e.type == SDL_WINDOWEVENT && e.window.event == SDL_WINDOWEVENT_EXPOSED) {
     // 再描画が必要な場合
@@ -86,8 +145,11 @@ int main(int argc, char* argv[]) {
     return 1;
   }
 
-  if (!(IMG_Init(IMG_INIT_PNG) & IMG_INIT_PNG)) {
+  int imgflag = IMG_INIT_PNG;
+  if (!(IMG_Init(imgflag) & imgflag)) {
     printf("SDL_imageを初期設定出来なかった：%s\n", SDL_GetError());
+    SDL_DestroyRenderer(renderer);
+    SDL_DestroyWindow(window);
     SDL_Quit();
     return 1;
   }
@@ -109,19 +171,41 @@ int main(int argc, char* argv[]) {
     imgfile = tmpname;
   }
 
+  const char* mimetype = getmime(imgfile);
+  SDL_Surface* imgsurface = NULL;
+  IMG_Animation* imganimate = NULL;
+
   // 画像の読込
-  SDL_Surface* imgsurface = IMG_Load(imgfile);
-  if (imgsurface == NULL) {
-    printf("画像の読込に失敗：%s\n", IMG_GetError());
-    SDL_DestroyRenderer(renderer);
-    SDL_DestroyWindow(window);
-    SDL_Quit();
-    return 1;
+  if (strcmp(mimetype, "image/gif") == 0) {
+    imganimate = IMG_LoadAnimation(imgfile);
+    if (imganimate == NULL) {
+      printf("画像の読込に失敗：%s\n", IMG_GetError());
+      SDL_DestroyRenderer(renderer);
+      SDL_DestroyWindow(window);
+      SDL_Quit();
+      return 1;
+    }
+  } else {
+    imgsurface = IMG_Load(imgfile);
+    if (imgsurface == NULL) {
+      printf("画像の読込に失敗：%s\n", IMG_GetError());
+      SDL_DestroyRenderer(renderer);
+      SDL_DestroyWindow(window);
+      SDL_Quit();
+      return 1;
+    }
   }
 
   // 画像の大きさの受取
-  int imgWidth = imgsurface->w;
-  int imgHeight = imgsurface->h;
+  int imgWidth = 0;
+  int imgHeight = 0;
+  if (strcmp(mimetype, "image/gif") == 0) {
+    imgWidth = imganimate->w;
+    imgHeight = imganimate->h;
+  } else {
+    imgWidth = imgsurface->w;
+    imgHeight = imgsurface->h;
+  }
   /* float aspectRatio = (float)imgWidth / imgHeight; */
 
   // 画面の大きさの受取
@@ -165,14 +249,18 @@ int main(int argc, char* argv[]) {
     return 1;
   }
 
-  texture = SDL_CreateTextureFromSurface(renderer, imgsurface);
-  SDL_FreeSurface(imgsurface);
+  if (strcmp(mimetype, "image/gif") == 0) {
+    texture = IMG_LoadTexture(renderer, imgfile);
+  } else {
+    texture = SDL_CreateTextureFromSurface(renderer, imgsurface);
+    SDL_FreeSurface(imgsurface);
   if (texture == NULL) {
     SDL_DestroyRenderer(renderer);
     SDL_DestroyWindow(window);
     SDL_Quit();
     return 1;
   }
+  }
 
   // メインループ
   SDL_Event e;
@@ -182,6 +270,10 @@ int main(int argc, char* argv[]) {
       windowevent(e);
     }
 
+    SDL_RenderClear(renderer);
+    SDL_RenderCopy(renderer, texture, NULL, NULL);
+    SDL_RenderPresent(renderer);
+
     // 休ませる
     SDL_Delay(DELAY_MS);
   }
@@ -190,6 +282,7 @@ int main(int argc, char* argv[]) {
   if (isurl) {
     remove(tmpname);
   }
+  if (strcmp(mimetype, "image/gif") == 0) IMG_FreeAnimation(imganimate);
   SDL_DestroyTexture(texture);
   SDL_DestroyRenderer(renderer);
   SDL_DestroyWindow(window);