main.cpp

#include "sdl_wrapper.hh"

#include <SDL2/SDL.h>

int main(int argc, char *argv[])
{
    SDL::init();
    
    SDL_Event e;
    bool quit{};
    while (!quit) {
        while (SDL_PollEvent(&e))
            if (e.type == SDL_QUIT)
                quit = true;
        SDL::render_clear();
        SDL::render_present();
    }

    SDL::quit();
}

sdl_wrapper.cpp

#include <cstdio>
#include <string>

#include <SDL2/SDL.h>
#include <SDL2/SDL_image.h>


#include "sdl_wrapper.hh"

/* Global SDL State */
static SDL_Window *window;
static SDL_Renderer *renderer;
static SDL_Texture *current_texture;

static constexpr char WINDOW_TITLE[] = "Motherload";
static constexpr int WINDOW_HEIGHT = 480;
static constexpr int WINDOW_WIDTH  = 640;
static constexpr int FPS           = 60;


/* static helper functions */
static SDL_Texture* load_texture(const std::string& path)
{
    SDL_Texture *new_texture = nullptr;

    SDL_Surface *loaded_surface = IMG_Load(path.c_str());
    if (!loaded_surface) {
        fprintf(stderr, "Unable to load image %s:\n%s\n", path.c_str(), IMG_GetError());
    } else {
        new_texture = SDL_CreateTextureFromSurface(renderer, loaded_surface);
        if (!new_texture) {
            fprintf(stderr, "Unable to create texture from %s:\n%s\n", path.c_str(), SDL_GetError());
        }
        SDL_FreeSurface(loaded_surface);
    }
    return new_texture;
}


bool SDL::init()
{
    if (SDL_Init(SDL_INIT_VIDEO) < 0) {
        fprintf(stderr, "SDL could not initialize: %s\n", SDL_GetError());
        return false;
    }

    window = SDL_CreateWindow(WINDOW_TITLE, SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED,
                              WINDOW_WIDTH, WINDOW_HEIGHT, SDL_WINDOW_SHOWN);
    if (!window) {
        fprintf(stderr, "Failed to create window: %s\n", SDL_GetError());
        return false;
    }

    renderer = SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC);
    if (!renderer) {
        fprintf(stderr, "Could not create renderer: %s\n", SDL_GetError());
        return false;
    }

    SDL_SetRenderDrawColor(renderer, 0xFF, 0xFF, 0xFF, 0xFF);

    if (!(IMG_Init(IMG_INIT_PNG) & IMG_INIT_PNG)) {
        fprintf(stderr, "SDL_image could not initialize: %s\n", IMG_GetError());
        return false;
    }

    return true;
}

void SDL::quit()
{
    SDL_DestroyTexture(current_texture);
    SDL_DestroyRenderer(renderer);
    SDL_DestroyWindow(window);
    IMG_Quit();
    SDL_Quit();
}

void SDL::render_clear()
{
    SDL_RenderClear(renderer);
}

void SDL::render_present()
{
    SDL_RenderPresent(renderer);
}

sdl_wrapper.hh

#pragma once

/* public functions */
namespace SDL {
    bool init();
    void quit();
    void render_clear();
    void render_present();
}