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#include "components/point.hpp"
#include "components/player.hpp"
#include "components/solid.hpp"
#include "components/texture.hpp"
#include "components/velocity.hpp"
#include "window.hpp"
#include <chrono>
#include <fstream>
#include <iostream>
#include <ranges>
#include <thread>
#include <entt/entt.hpp>
#include <sol/sol.hpp>
#include <SDL2/SDL.h>
constexpr std::chrono::duration<double> FRAME_TIME (1.0 / 60.0);
static bool handleInputs(entt::registry& registry);
int main(int argc, const char *argv[])
{
entt::registry registry;
sol::state lua;
if (auto err = sdl2Initialize(); err)
return err;
for (auto file : std::views::counted(argv + 1, argc - 1))
lua.script_file(file);
if (auto entities = lua.get<sol::optional<sol::table>>("entities"); entities) {
entities->for_each([®istry](sol::object _, sol::object val) {
const auto ent = registry.create();
auto tbl = val.as<sol::table>();
if (auto solid = tbl.get<sol::optional<std::string>>("solid"); solid)
registry.emplace<Solid>(ent, *solid);
if (auto tex = tbl.get<sol::optional<std::string>>("texture"); tex)
registry.emplace<Texture>(ent, *tex);
if (auto point = tbl.get<sol::optional<sol::table>>("point"); point)
registry.emplace<Point>(ent, point->get<float, float>("x", "y"));
if (auto vel = tbl.get<sol::optional<sol::table>>("velocity"); vel)
registry.emplace<Velocity>(ent, vel->get<float, float>("x", "y"));
if (auto player = tbl.get<sol::optional<sol::table>>("player"); player)
registry.emplace<Player>(ent);
});
} else {
std::cout << "No entities defined..." << std::endl;
}
do {
const auto now = std::chrono::high_resolution_clock::now();
SDL_RenderClear(renderer);
registry.view<Texture, Point>().each([](auto& tex, auto& p) { tex(renderer, p); });
SDL_RenderPresent(renderer);
registry.view<Velocity, Point>().each([](auto& v, auto& p) { p += v; });
registry.view<Solid, Point>().each(
[®istry](auto& s, auto& p) {
registry.view<Player, Point, Velocity, Texture>().each(
[&s, &p](auto& _, auto& pp, auto& pv, auto& pt) {
if (const auto c = s.collision(pp + pt.dim()); c) {
pv.y = (std::abs(c) > 1.f) ? c * 0.25f : 0.f;
} else {
pv.y += 0.1f;
}
});
});
std::this_thread::sleep_until(now + FRAME_TIME);
} while (handleInputs(registry));
}
bool handleInputs(entt::registry& registry)
{
bool quit = false;
for (SDL_Event e; SDL_PollEvent(&e);) {
if (e.type == SDL_QUIT) {
quit = true;
} else if (e.type == SDL_KEYDOWN && !e.key.repeat) {
auto view = registry.view<Player, Velocity>();
switch (e.key.keysym.sym) {
case SDLK_d:
view.each([](Player& p, Velocity& v) { v.x += 1.5f; });
break;
case SDLK_a:
view.each([](Player& p, Velocity& v) { v.x -= 1.5f; });
break;
case SDLK_SPACE:
view.each([](Player& p, Velocity& v) { if (v.y <= 0.f) v.y -= 3.f; });
break;
}
} else if (e.type == SDL_KEYUP && !e.key.repeat) {
auto view = registry.view<Player, Velocity>();
switch (e.key.keysym.sym) {
case SDLK_d:
view.each([](Player& p, Velocity& v) { v.x -= 1.5f; });
break;
case SDLK_a:
view.each([](Player& p, Velocity& v) { v.x += 1.5f; });
break;
}
}
}
return !quit;
}
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