// A class to describe a group of Particles

// An ArrayList is used to manage the list of Particles

class ParticleSystem {

ArrayList particles; // An arraylist for all the particles

PVector origin; // An origin point for where particles are born

ParticleSystem(int num, PVector v) {

particles = new ArrayList(); // Initialize the arraylist

origin = v.get(); // Store the origin point

for (int i = 0; i < num; i++) {

particles.add(new Particle(origin)); // Add "num" amount of particles to the arraylist

}

}

void run() {

// Cycle through the ArrayList backwards b/c we are deleting

for (int i = particles.size()-1; i >= 0; i--) {

Particle p = (Particle) particles.get(i);

p.run();

if (p.dead()) {

particles.remove(i);

}

}

}

void addParticle() {

particles.add(new Particle(origin));

}

void addParticle(float x, float y, color c) {

particles.add(new Particle(new PVector(x,y), c));

}

void addParticle(float x, float y, float vx, float vy) {

particles.add(new Particle(new PVector(x,y)));

}

void addParticle(Particle p) {

particles.add(p);

}

// A method to test if the particle system still has particles

boolean dead() {

if (particles.isEmpty()) {

return true;

} else {

return false;

}

}

}