SDL (Simple DirectMedia Layer)/Graphics/Rendering other image formats

Rendering other image formats requires the use of another SDL library: SDL_image. However, the process of rendering different image formats is very much the same as rendering BMP images. In this section, we'll demonstrate how to render a PNG file onto a window. You can download the source code of this section in this GitLab repository. All source code is stored in this group. Importing the SDL_image library We'll import the SDL_image library, in wikibook.h, in the following fashion: #ifdef _WIN32 #include <SDL/SDL.h> /* Windows-specific SDL2 library */ #include <SDL_image.h> #else #include <SDL2/SDL.h> /* macOS- and GNU/Linux-specific */ #include <SDL2/SDL_image.h> #endif Initialising the image subsystem Right after initialising the SDL subsytems, we would need to initialise the image subsystem using IMG_Init. Given the parameter int flags, it returns flags on success. We'll want to render a PNG file so we would want to use the flag IMG_INIT_PNG. There are other flags like IMG_INIT_JPG (check IMG_Init for more information). To initialise multiple flags use the | OR operator, for example: const int FLAGS = IMG_INIT_PNG | IMG_INIT_JPG; You'll also have to use IMG_Quit to close the subsystem. /* Initialise SDL_image */ const int FLAGS = IMG_INIT_PNG; if (IMG_Init(FLAGS) != FLAGS) { fprintf(stderr, "SDL_image failed to initialise: %s\n", IMG_GetError()); return -1; } /* Automatically execute IMG_Quit at exit */ atexit(IMG_Quit); Since we're using SDL_image, we have to use IMG_GetError in place of SDL_GetError. Loading the image Loading the image is very simple, just use the IMG_Load function on a SDL_Surface. Like with IMG_Init, we must use IMG_GetError. wb->image = IMG_Load(WB_IMAGE_PATH); if (wb->image == NULL) { fprintf(stderr, "WikiBook failed to load image: %s\n", IMG_GetError()); return -1; } Remember, to make sure that the file path to the image is correct, i.e. WB_IMAGE_PATH! We're rendering a PNG image! . -