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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 <lua.hpp>
#include <entityx/entityx.h>
#include <Script/entityx/entity_lua.hpp>
#include <LuaBridge/LuaBridge.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);
static void LuaTest(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);
}
LuaTest();
// 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);
}
}
struct Position : entityx::Component<Position>
{
Position(float _x, float _y): x(_x), y(_y) {}
Position(void){x = y = 0.0;}
float x,y;
};
using namespace entityx;
using namespace entityx::lua;
namespace lb = luabridge;
EventManager events;
EntityManager entities(events);
lua_State* L;
lb::LuaRef spawn(lb::LuaRef ref)
{
lb::LuaRef entity(L);
entity = lb::newTable(L);
if (ref.isTable()) {
Entity e = entities.create();
for (auto &&comp : lb::pairs(ref)) {
if (comp.first.cast<std::string>() == "Position") {
float x = comp.second["x"];
float y = comp.second["y"];
entity["Position"] = e.assign<Position>(x, y).get();
} else if (comp.first.cast<std::string>() == "init") {
entity["init"] = comp.second;
}
}
} else {
std::cerr << "Parameter to spawn() must be a table!" << std::endl;
}
return entity;
}
void LuaTest(void)
{
L = luaL_newstate();
luaL_openlibs(L);
lb::getGlobalNamespace(L).
beginNamespace("comp")
.beginClass<Position>("Position")
.addConstructor<void(*)(float, float)>()
.addProperty("x", &Position::x)
.addProperty("y", &Position::y)
.endClass()
.endNamespace();
lb::getGlobalNamespace(L)
.beginNamespace("game")
.addFunction("spawn", spawn)
.endNamespace();
if (luaL_dofile(L, "Scripts/init.lua"))
{
std::cout << "Lua error: " << lua_tostring(L, -1) << std::endl;
}
entities.each<Position>([&](Entity e, Position& p){ (void)e;std::cout << p.x << std::endl;});
lua_close(L);
}
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