code/wander-ball/wander.c

#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>

#include <SDL2/SDL.h>

typedef struct {
        SDL_Window *win;
        SDL_Renderer *ren;
        SDL_Event *ev;
        bool is_initialized;
        int flags;
        bool running;
} env;

typedef struct {
        int x;
        int y;
} vec2d;

bool init_env(
  env *env,
  int sdl_flags,
  char* win_name,
  vec2d win_size,
  int renderer_flags)
{
        if (env->is_initialized)
                return false;
        SDL_Init(sdl_flags);
        env->flags = sdl_flags;
        env->win = SDL_CreateWindow(win_name,
                                    SDL_WINDOWPOS_UNDEFINED,
                                    SDL_WINDOWPOS_UNDEFINED,
                                    win_size.x,
                                    win_size.y,
                                    SDL_WINDOW_OPENGL);
        if (!env->win) {
                fprintf(stderr, "could not create window: %s\n", SDL_GetError());
                return false;
        }

        env->ren = SDL_CreateRenderer(env->win,
                                      -1,
                                      renderer_flags);
        
        if (!env->win) {
                fprintf(stderr, "could not create renderer: %s\n", SDL_GetError());                                                                                                                     
                return false;
        }
        env->running = false;

        return true;
}

void process_event(env *env){
        switch(env->ev->type)
        {
                case SDL_QUIT:
                        env->running = false;
                        break;
        }

}

void run(env *env) 
{
        if (!env->is_initialized) {
                fprintf(stderr, "event not initialized.");
                return;
        }
        env->running = true;
        while (env->running) {
                while(SDL_PollEvent(env->ev))
                        process_event(env);
        }
}

void destroy_env(env *env)
{
        env->is_initialized = false;
        SDL_DestroyRenderer(env->ren);
        SDL_DestroyWindow(env->win);
        env->flags = 0;
}

int main(int argc, char** argv)
{
        env e;
        e.is_initialized = false;
        vec2d win_size = { .x = 800, .y = 600 };
        if (init_env(&e, 
                     SDL_INIT_VIDEO,
                     "Wander",
                     win_size,
                     SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC)){
                fprintf(stdout, "cannot initialize, exiting\n");
                return 1;
        }
        


        run(&e);
        destroy_env(&e);
}