twang-mp/TWANG32/Particle.h

#include "Arduino.h"
#define FRICTION 1

class Particle
{
  public:
    void Spawn(int pos, int life, int aging_speed, const int color[3]);
    void Tick(int USE_GRAVITY);
    void Kill();
    bool Alive();
    int _pos;
    int _power;
    int _color[3];
  private:
    int _life;
    int _alive;
    int _sp;
    int _aging;
};

void Particle::Spawn(int pos, int life, int aging_speed, const int color[3]){
    _pos = pos;
    _sp = random(-life, life);
    _power = 255;
    _alive = 1;
    _life = life - abs(_sp);
    _aging = aging_speed;

    for (int i = 0; i< 3; i++) _color[i] = color[i];
}

void Particle::Tick(int USE_GRAVITY){
    if(_alive){
        _life ++;
        if(_sp > 0){
            _sp -= _life/10;
        }else{
            _sp += _life/10;
        }
        if(USE_GRAVITY && _pos > 500) _sp -= 10;
        _power = 100 - _aging*_life;
        if(_power <= 0){
            Kill(); 
        }else{
            _pos += _sp/7.0;
            if(_pos > 1000){
                _pos = 1000;
                _sp = 0-(_sp/2);
            }
            else if(_pos < 0){
                _pos = 0;
                _sp = 0-(_sp/2);
            }
        }
    }
}

bool Particle::Alive(){
    return _alive;
}

void Particle::Kill(){
    _alive = 0;
}