Fathopert, 10 June 2022
(upd. 21 June 2022)
SDL2 is a popular ะก game develoment library. In this article, we will build a basic SDL2 project. I hope it will be helpful for beginners.
I work in Windows 11 and use these versions of programs and libraries:
Download this development library from the official website:
Unzip the archive, navigate into the SDL2-<version> folder and install the library with the following commands:
> ./configure > make > sudo make install
Note: you can delete this folder after the installation is completed.
Now let's activate autocompletion for SDL2 in VS Code. Launch VS Code, open Command Palette with Ctrl+Shift+P. Find Preferences: Open Settings (JSON) and press Enter. Add this line to the opened settings.json:
C_Cpp.default.includePath: ["/usr/local/include/SDL2"]or update the existing list in
C_Cpp.default.includePath if you used this parameter before.
In my case, the added line looked like this:
Now we are ready to code!
Download this development library from the official website:
Unzip the archive and remember the location of the SDL2-<version> folder.
I extracted the library to C:/_my_files and renamed the directory to just SDL2.
After this, go to the <path-to-sdl2>/x86_64-w64-mingw32/include/SDL2/ and
change the value of the prefix variable in sdl2-config.cmake to
"${CMAKE_CURRENT_LIST_DIR}/../../../"
Let's turn on autocompletion for SDL2 in VS Code. Launch VS Code, open Command Palette with Ctrl+Shift+P. Find Preferences: Open Settings (JSON) and press Enter. Add this line to the opened settings.json:
C_Cpp.default.includePath: [<path-to-sdl2>/x86_64-w64-mingw32/include/SDL2]or update the existing list in
C_Cpp.default.includePath if you used this parameter before.
In my case, the added line looked like this:
Note:
Similarly (with the same commands) you can install
the SDL_image library.
Download the source code
here.
Now we are ready to code!
- project folder | |--- src (a folder) | | | |--- main.c | |--- include (a folder) | |--- CMakeLists.txt
The main.c file contains the following code:
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#define SDL_MAIN_HANDLED
#include "SDL2/SDL.h"
/* macros */
#define SCREEN_WIDTH 800
#define SCREEN_HEIGHT 600
#define WINDOW_TITLE "Hello from SDL2"
/* variables */
static SDL_Window* window;
static SDL_Renderer* renderer;
static SDL_Event event;
static bool running;
/* function implementations */
int
main(int argc, char** argv)
{
/* Initializing SDL2 */
if (SDL_Init(SDL_INIT_VIDEO)) {
printf("Unable to initialize SDL: %s\n", SDL_GetError());
return -1;
}
/* Creating a SDL window */
window = SDL_CreateWindow(WINDOW_TITLE,
SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED,
SCREEN_WIDTH, SCREEN_HEIGHT, SDL_WINDOW_SHOWN);
if (!window) {
printf("Could not create a window: %s\n", SDL_GetError());
return -1;
}
/* Creating a renderer */
renderer = SDL_CreateRenderer(window, -1,
SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC);
if (!renderer) {
printf("Could not create a renderer: %s\n", SDL_GetError());
return -1;
}
/* Background color r g b a */
SDL_SetRenderDrawColor(renderer, 110, 177, 255, 255);
running = true;
while (running) {
/* Processing events */
while (SDL_PollEvent(&event)) {
if (event.type == SDL_QUIT) {
running = false;
}
}
/* Clearing the screen */
SDL_RenderClear(renderer);
/* Showing what was drawn */
SDL_RenderPresent(renderer);
}
/* Releasing resources */
SDL_DestroyRenderer(renderer);
SDL_DestroyWindow(window);
SDL_Quit();
return 0;
}
Write this code in the CMakeLists.txt file. This script works on both Linux and Windows. Do not forget replace <path-to-sdl2> with your path.
cmake_minimum_required(VERSION 3.2)
project(hello_sdl LANGUAGES C VERSION 1.0)
set(CMAKE_C_STANDARD 99)
# Set the folder where the executable will be saved
set(CMAKE_RUNTIME_OUTPUT_DIRECTORY "result")
# Tell CMake create an EXE file from the specified C files
file(GLOB C_SRC ${PROJECT_SOURCE_DIR}/src/*.c)
add_executable(hello_sdl ${C_SRC})
# Tell CMake where to find SDL2 on Windows
if(WIN32)
list(APPEND CMAKE_PREFIX_PATH
"<path-to-sdl2>/x86_64-w64-mingw32/lib/cmake/SDL2")
endif()
# Looking for SDL2
find_package(SDL2 REQUIRED)
if(SDL2_FOUND)
message(STATUS "SDL2 was found!")
else()
message(STATUS "SDL2 was not found!")
endif()
# find_package(SDL2_image REQUIRED)
# if(SDL2_image_FOUND)
# message(STATUS "SDL_image was found!")
# else()
# message(STATUS "SDL_image was not found!")
# endif()
# Copy SDL2.dll to the folder with the executable on Windows
if(WIN32)
add_custom_command(TARGET hello_sdl POST_BUILD COMMAND
${CMAKE_COMMAND} -E copy_if_different
"${SDL2_PREFIX}/bin/SDL2.dll" "${CMAKE_RUNTIME_OUTPUT_DIRECTORY}")
endif()
# Tell CMake where to look for header files.
# PRIVATE means 'using only for this target (i.e. for hello_sdl)'
target_include_directories(hello_sdl
PRIVATE ${SDL2_INCLUDE_DIRS}
PRIVATE ${PROJECT_SOURCE_DIR}/include)
# Link required libraries
target_link_libraries(hello_sdl
PRIVATE SDL2::SDL2
PRIVATE SDL2::SDL2main)
# PRIVATE SDL2_image)
# Without this flag, CMake compiles "shared library" on Linux
if(UNIX)
target_link_options(hello_sdl PRIVATE "-no-pie")
endif()
With this file, CMake will understand how to build the executable for our program.
Open a terminal or cmd in the project folder, create a build directory, and navigate into it:
> mkdir build > cd build
Then generate a Makefile for make and build the executable file.
On Linux, use the following comands:
> cmake -G"Unix Makefiles" -DCMAKE_C_FLAGS_RELEASE=-O3 -DCMAKE_BUILD_TYPE=RELEASE .. > cmake --build .
On Windows:
> cmake -G"MinGW Makefiles" -DCMAKE_C_FLAGS_RELEASE=-O3 -DCMAKE_BUILD_TYPE=RELEASE .. > cmake --build .
If there are no errors, the executable file hello_sdl will appear in the build/result folder.
Now let's launch our program!
On Linux, use the following comands:
> cd result > ./hello_sdl
On Windows:
> cd result > hello_sdl.exe
The window will appear with the previously specified size and title:
Thus, we have made a basic SDL2 project using C. For additional information, I suggest you check out the References section.