CMakeLists.txt for SDL3 projects

CMakeLists.txt

# CMakeLists.txt project file for SDL3 projects
# 
# NB: SDL_image, SDL_ttf and SDL_mixer are not yet tagged properly
# in github to be included via this fetch mechanism.
# As they are updated, I will endevour to keep this gist updated
cmake_minimum_required(VERSION 3.30)
project(hello_sdl3_with_cmake C)

set(CMAKE_C_STANDARD 23)

# Include the command that downloads libraries
include(FetchContent)

# define a function for adding git dependencies
function(include_dependency libName gitURL gitTag)
    # setup the declare
    FetchContent_Declare(${libName}
            GIT_REPOSITORY ${gitURL}
            GIT_TAG        ${gitTag}
            GIT_SHALLOW    TRUE
            GIT_PROGRESS   TRUE
    )

    FetchContent_MakeAvailable(${libName})
endfunction()

# add SDL3 support
find_package(SDL3 QUIET)
if (NOT SDL3_FOUND)
    message(STATUS "Getting SDL3 from Github")
    include_dependency(SDL3 https://github.com/libsdl-org/SDL.git release-3.2.0)
else()
    message(STATUS "Using local SDL3")
endif()

add_executable(hello_sdl3_with_cmake WIN32 main.c)

# set the include directory
target_include_directories(hello_sdl3_with_cmake PUBLIC ${SDL3_INCLUDE_DIRS})

target_compile_definitions(hello_sdl3_with_cmake PRIVATE SDL_MAIN_USE_CALLBACKS)

# link all libraries to the project
target_link_libraries(hello_sdl3_with_cmake PRIVATE SDL3::SDL3)

if (WIN32)
    add_custom_command(
            TARGET hello_sdl3_with_cmake POST_BUILD
            COMMAND "${CMAKE_COMMAND}" -E copy_if_different "$<TARGET_FILE:SDL3::SDL3>" "$<TARGET_FILE_DIR:hello_sdl3_with_cmake>"
            VERBATIM
    )
endif()

main.c

#include <stdio.h>

#include <SDL3/SDL.h>
#include <SDL3/SDL_main.h>

static SDL_Window *window = NULL;
static SDL_Renderer *renderer = NULL;

SDL_AppResult SDL_AppInit(void **appstate, int argc, char* argv[])
{
    if (SDL_Init(SDL_INIT_VIDEO) == false)
    {
        SDL_ShowSimpleMessageBox(SDL_MESSAGEBOX_ERROR, "Couldn't initialize SDL!", SDL_GetError(), NULL);
        return SDL_APP_FAILURE;
    }

    // 800x450 is 16:9
    if (SDL_CreateWindowAndRenderer("hello SDL3 with cmake", 800, 450, 0, &window, &renderer) == false)
    {
        SDL_ShowSimpleMessageBox(SDL_MESSAGEBOX_ERROR, "Couldn't create window/renderer!", SDL_GetError(), NULL);
        return SDL_APP_FAILURE;
    }

    // return success!
    return SDL_APP_CONTINUE;
}

// This function runs when a new event occurs
SDL_AppResult SDL_AppEvent(void *appstate, SDL_Event *event)
{
    switch (event->type)
    {
        case SDL_EVENT_QUIT:
            // end the program, reporting success to the OS
            return SDL_APP_SUCCESS;
        case SDL_EVENT_KEY_DOWN:
            if (event->key.key == SDLK_ESCAPE)
            {
                // end the program on ESC key,
                // returning success to the OS
                return SDL_APP_SUCCESS;
            }
        default:
            break;
    }

    // return continue to continue
    return SDL_APP_CONTINUE;
}

// This function runs once per frame, and is the heart of the program
SDL_AppResult SDL_AppIterate(void *appstate)
{
    SDL_SetRenderDrawColor(renderer, 135, 206, 235, 255);
    SDL_RenderClear(renderer);
    SDL_RenderPresent(renderer);

    // return continue to continue
    return SDL_APP_CONTINUE;
}

// This function runs once at shutdown
void SDL_AppQuit(void *appstate, SDL_AppResult result)
{
   // SDL will clean up the window/renderer for us.
}