Creating the Main Loop with SDL2

Handling Window Resize Events in SDL2

How do I handle window resize events in SDL2 to adjust my rendering?

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When your SDL2 window is resized, you'll need to adjust your rendering to fit the new window size. This involves handling the SDL_WINDOWEVENT event and checking for the SDL_WINDOWEVENT_RESIZED event type. Here’s how to set it up:

1#include <SDL.h>
2#include <iostream>
3
4int main(int argc, char** argv) {
5  SDL_Init(SDL_INIT_VIDEO);
6  SDL_Window* window = SDL_CreateWindow(
7    "Resize Example", 100, 100, 640, 480,
8    SDL_WINDOW_RESIZABLE);
9  SDL_Renderer* renderer = SDL_CreateRenderer(
10    window, -1, SDL_RENDERER_ACCELERATED);
11
12  bool running = true;
13  SDL_Event event;
14  while (running) {
15    while (SDL_PollEvent(&event)) {
16      if (event.type == SDL_QUIT)
17        running = false;
18      if (event.type == SDL_WINDOWEVENT &&
19        event.window.event ==
20        SDL_WINDOWEVENT_RESIZED) {
21        std::cout << "Window resized to "
22          << event.window.data1 << "x"
23          << event.window.data2 << "\n";
24        SDL_RenderSetLogicalSize(renderer,
25          event.window.data1, event.window.data2);
26      }
27    }
28
29    SDL_SetRenderDrawColor(renderer, 0, 0, 0, 255);
30    SDL_RenderClear(renderer);
31    // Rendering code here
32    SDL_RenderPresent(renderer);
33  }
34
35  SDL_DestroyRenderer(renderer);
36  SDL_DestroyWindow(window);
37  SDL_Quit();
38  return 0;
39}

1Window resized to 694x541
2Window resized to 694x541

The above code updates the renderer to match the new window size whenever it is resized, ensuring that the rendering area remains consistent with the window dimensions.

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