// 3. Create a renderer for accelerated 2D SDL_Renderer* renderer = SDL_CreateRenderer(window, NULL, SDL_RENDERER_ACCELERATED); if (!renderer) { SDL_Log("SDL_CreateRenderer Error: %s", SDL_GetError()); SDL_DestroyWindow(window); SDL_Quit(); return 1; }
// 6. Cleanup SDL_DestroyRenderer(renderer); SDL_DestroyWindow(window); SDL_Quit(); return 0; } 1. Initialization – SDL_Init(SDL_INIT_VIDEO) returns a boolean (true on success). Unlike SDL2’s integer return, SDL3 uses bool consistently. Error messages are retrieved via SDL_GetError() . We only initialize the video subsystem because we don’t need audio or game controllers.
– SDL_CreateWindow now takes width, height, and flags directly, omitting the separate x,y parameters (defaulting to centered). The SDL_WINDOW_RESIZABLE flag allows the user to resize the window. The window title is set to “SDL3 Bouncing Ball”. sdl3 example
– We store position and velocity as floats for smooth sub-pixel movement. The key addition in SDL3’s API is the use of SDL_GetTicks() returning Uint64 (milliseconds), which is far less prone to overflow than SDL2’s 32-bit value. Delta time calculation ensures the ball moves at a consistent speed regardless of frame rate.
// sdl3_bounce.c // Compile (Linux/macOS): gcc sdl3_bounce.c -o bounce `pkg-config --cflags --libs sdl3` // Compile (Windows with vcpkg): cl sdl3_bounce.c /Ipath\to\SDL3\include /link path\to\SDL3\lib\SDL3.lib #include <SDL3/SDL.h> #include <stdio.h> #include <stdbool.h> We only initialize the video subsystem because we
– SDL3 has renamed many event types. The quit event is now SDL_EVENT_QUIT (instead of SDL_QUIT ). Key events follow a similar pattern: SDL_EVENT_KEY_DOWN and the key code is accessed via event.key.key (where SDLK_ESCAPE is unchanged). The event loop is non-blocking thanks to SDL_PollEvent .
#define WINDOW_WIDTH 800 #define WINDOW_HEIGHT 600 #define BALL_RADIUS 20 creates a renderer
Introduction For decades, the Simple DirectMedia Layer (SDL) has been the silent workhorse of cross-platform game development and multimedia applications. From indie darlings like Celeste to AAA titles and emulators like RetroArch, SDL provides a unified interface to handle windows, input, graphics, and audio across Windows, macOS, Linux, iOS, and Android. In early 2024, the long-awaited SDL3 was released, bringing modernized APIs, better GPU integration, and a cleaner, more predictable programming model. This essay provides a complete, runnable example of an SDL3 application and dissects every component, demonstrating why SDL3 represents a significant evolution from its predecessors. The Big Picture: What SDL3 Changes Before diving into code, it is crucial to understand SDL3’s philosophical shift. SDL2 relied heavily on SDL_Surface for software rendering and SDL_Texture for hardware-accelerated 2D. Initialization was monolithic, and many functions returned -1 on error. SDL3 simplifies this: initialization is now explicit and fine-grained, many obsolete functions have been removed, and the new GPU API (not used in this basic example) offers low-overhead access to Vulkan, Metal, and Direct3D 12. Furthermore, SDL3 adopts a more consistent naming convention (e.g., SDL_CreateWindow remains, but many event and input functions have been renamed for clarity). Our example will focus on creating a window, handling basic events, and rendering a simple animated shape using the modernized 2D renderer. The Complete Example: An Animated Bouncing Ball Below is a complete, working SDL3 program written in C. It opens an 800x600 window, creates a renderer, and animates a blue ball bouncing off the window’s edges. The code assumes SDL3 development libraries are installed (e.g., via vcpkg, Homebrew, or source compilation).