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/**
* @file main.cpp
* The main file, where the magic begins.
*
* Copyright (C) 2019 Clyne Sullivan
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
#include <entityx/entityx.h>
#include <SDL2/SDL.h>
#include <atomic>
#include <chrono>
#include <iostream>
#include <memory>
#include <thread>
class Window {
private:
constexpr static const char *title = "gamedev2";
constexpr static int width = 640;
constexpr static int height = 480;
static std::unique_ptr<SDL_Window, void (*)(SDL_Window *)> window;
static SDL_GLContext context;
static void destroyWindow(SDL_Window *w) {
SDL_GL_DeleteContext(context);
SDL_DestroyWindow(w);
}
public:
static int init(void) {
if (SDL_InitSubSystem(SDL_INIT_VIDEO) != 0) {
std::cerr << "SDL video failed to initialize: "
<< SDL_GetError() << std::endl;
return -1;
}
window.reset(SDL_CreateWindow(title,
SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED,
width, height,
SDL_WINDOW_OPENGL));
if (window.get() == nullptr) {
std::cerr << "SDL window creation failed: "
<< SDL_GetError() << std::endl;
return -1;
}
context = SDL_GL_CreateContext(window.get());
return 0;
}
static void render(void) {
SDL_GL_SwapWindow(window.get());
}
};
std::unique_ptr<SDL_Window, void (*)(SDL_Window *)> Window::window (nullptr,
Window::destroyWindow);
SDL_GLContext Window::context;
std::atomic_bool shouldRun;
static void renderLoop(void);
static void logicLoop(void);
int main([[maybe_unused]] int argc, [[maybe_unused]] char *argv[])
{
// Initialize SDL
if (SDL_Init(0) != 0) {
std::cerr << "SDL failed to initialize: " << SDL_GetError()
<< std::endl;
return -1;
} else {
atexit(SDL_Quit);
}
// Create our window
Window::init();
// Start game
shouldRun.store(true);
std::thread logic (logicLoop);
renderLoop();
logic.join();
return 0;
}
void renderLoop(void)
{
while (shouldRun.load()) {
Window::render();
std::this_thread::yield();
}
}
void logicLoop(void)
{
using namespace std::chrono_literals;
std::cout << "Press escape to exit." << std::endl;
while (shouldRun.load()) {
for (SDL_Event event; SDL_PollEvent(&event);) {
switch (event.type) {
case SDL_KEYUP:
// Exit game on escape
if (event.key.keysym.sym == SDLK_ESCAPE)
shouldRun.store(false);
break;
default:
break;
}
}
std::this_thread::sleep_for(100ms);
}
}
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