Why destroy windows before exiting?

Failing to destroy windows before exiting a program can lead to several problems, including resource leaks and undefined behavior. When you create a window with SDL_CreateWindow(), the SDL library allocates resources like memory, GPU buffers, and operating system handles.

These resources must be explicitly released by calling SDL_DestroyWindow() before the program terminates.

If a program exits without destroying its windows, the operating system may clean up the resources eventually, but this is not guaranteed to happen in a timely or consistent manner.

On some systems, lingering resources can cause performance issues, graphical glitches, or even crashes in other applications.

Here is an example of correctly destroying a window:

1#include <SDL.h>
2
3int main() {
4  SDL_Init(SDL_INIT_VIDEO);
5  SDL_Window* Window{
6    SDL_CreateWindow("Example",
7      100, 100, 640, 480, 0)
8  };
9
10  // ... Program logic ...
11
12  SDL_DestroyWindow(Window); 
13  SDL_Quit();
14  return 0;
15}

By explicitly calling SDL_DestroyWindow(), you ensure that all resources allocated for the window are properly released.

For larger applications managing multiple windows, tools like a WindowManager class can help automate this cleanup process within its destructor. Always clean up resources to maintain stability and avoid hard-to-diagnose issues.