Particle3D[] tracers;
Attractor attractor;
Repulsor[] repulsors;
Vec3D light;

float MAX_STEER=.1f;
float MAX_VEL=1.0f;
int NUM_REPULSORS = 100;
int NUM_TRACERS = 100;

void setup(){
  size(800,800);
  background(120);
  noStroke();
  randomTracers();
  Vec3D target = new Vec3D(0,0,0);
  attractor = new Attractor(target,20f,1f);
  randomRepulsors();
  light = randomLight();
  smooth();

}

void draw(){

  translate(400,400); 
  rotate(HALF_PI);
  /*for(int i=0;i<NUM_REPULSORS;i++){
    ellipse(repulsors[i].pos.x,repulsors[i].pos.y,4,4);
  }*/
 
  for (int t=0;t<NUM_TRACERS;t++){

    Vec3D steer = new Vec3D();
    steer = steer.add(attractor.steeringForce(tracers[t], tracers[t].initPos.scale(-1f,1f,1f)));
    for(int i=0;i<NUM_REPULSORS;i++){

      steer = steer.add(repulsors[i].steeringForce(tracers[t]));

    }

    if (steer.size > MAX_STEER) steer = steer.mul(MAX_STEER / steer.size);
    tracers[t].update(steer); 
    stroke((int)random(120.0f),(int)random(40.0f),(int)random(40.0f),20);
    float s = random(40.0f);
    if (tracers[t].vel.size>.5f) line(tracers[t].pos.x+s*tracers[t].vel.y+random(-4f,4f),tracers[t].pos.y-s*tracers[t].vel.x+random(-4f,4f),tracers[t].pos.x-s*tracers[t].vel.y+random(-4f,4f),tracers[t].pos.y+s*tracers[t].vel.x+random(-4f,4f));
    noStroke();
    fill(255,120);
    //ellipse(tracers[t].pos.x+light.x,tracers[t].pos.y+light.y,4,4);
    ellipse(tracers[t].pos.x,tracers[t].pos.y,4,4);
    fill(0,120);
    ellipse(tracers[t].pos.x,tracers[t].pos.y,2,2);
    if(tracers[t].pos.x>tracers[t].age) tracers[t] = randomTracer();
    if ((tracers[t].vel.size<.5f)&&(random(100f)<5f)) tracers[t] = randomTracer();
  }





}


Particle3D randomTracer(){
  Vec3D pos = new Vec3D(-420f,random(-400f,400f),0);
  Vec3D vel = new Vec3D(1f,0f,0f);
  vel = vel.mul(MAX_VEL);
  return new Particle3D(pos, vel); 

}

Vec3D randomLight(){
  Vec3D pos = new Vec3D(random(-1f,1f),random(-1f,1f),0);
  pos = pos.normalize();  
  return pos; 

}

void randomRepulsors(){
  repulsors = new Repulsor[NUM_REPULSORS];
  for(int i=0;i<NUM_REPULSORS;i++){
    Vec3D pos = new Vec3D(random(-380f,380f),random(-380f,380f),0);
    repulsors[i] = new Repulsor(pos,10f,1f);

  }


}

void randomTracers(){
  tracers = new Particle3D[NUM_TRACERS];
  for(int i=0;i<NUM_TRACERS;i++){
    tracers[i] = randomTracer();
  }


}

void mousePressed(){
  background(150);
  randomTracers();
  randomRepulsors();
  light = randomLight();

}