#define OLC_PGE_APPLICATION
#include "olcPixelGameEngine.h"
#include <iostream>
#include <vector>
#include <algorithm>
struct Particle
{
    float x, y;
    float dx, dy;

    Particle(float ix, float iy, float idx, float idy) : x(ix), y(iy), dx(idx), dy(idy)
    {};
};
class GameExample : public olc::PixelGameEngine

{
public:
    std::vector <Particle> particles;
    static const int N = 150;
    static const int SPEED = 150;
    GameExample()
    {
        sAppName = "GameExample";

    }

    bool OnUserCreate() override
    {
        for (int i=0;i<N;i++)
        {
            particles.push_back({ ScreenWidth() / 2.0f,ScreenHeight() / 2.0f,rand() % SPEED -SPEED / 2.0f,-rand() % SPEED*1.0f  });
        }
        return true;
    }

    bool OnUserUpdate(float fElapsedTime) override
    {
        int count = std::count_if (particles.begin(), particles.end(), [this](Particle p) {return (p.x<0 || p.y<0 || p.x>ScreenWidth() || p.y>ScreenHeight()); });
        particles.erase(std::remove_if(particles.begin(), particles.end(), [this](Particle p) {return (p.x<0 || p.y<0 || p.x>ScreenWidth() || p.y>ScreenHeight()); }), particles.end());
        FillRect(0, 0, ScreenWidth(), ScreenHeight(), olc::BLACK);
        std::cout << count << std::endl;

        for (auto p:particles)
        {
            Draw(p.x, p.y, olc::RED);
        }
        for (auto &p : particles)
        {

            p.x += p.dx;
            p.y += p.dy;
            p.dy += 0.1;
        };
        for (int i = 0; i< count; i++)
        {
            particles.push_back({ ScreenWidth() / 2.0f,ScreenHeight() / 2.0f,rand() % SPEED - SPEED / 2.0f,-rand() % SPEED*1.0f });
        }

        return true;
    }

};


int main()
{
    GameExample game;
    if (game.Construct(800, 600, 1, 1))
    {
        game.Start();
    }

    return 0;
}