constructor(){

    this.position = createVector(random(-sizeX/2,sizeX/2), random(-sizeY/2, sizeY/2), random(-sizeZ/2,sizeZ/2));

    this.velocity = p5.Vector.random3D();

    this.velocity.setMag(random(2,4));

    this.acceleration = createVector();

    this.maxForce  = 0.02;

    this.maxSpeed = 2;

    this.coloring = p5.Vector.random3D().setMag(255);

    this.sizing = random(100,500);

  }

  align(boids){

    let perceptionRadius = 20;

    let steering = createVector();

    let total = 0;

    for(let other of boids){

      let d = dist(this.position.x, this.position.y, this.position.z, other.position.x, other.position.y,other.position.z);

      if(other != this && d < perceptionRadius){

      steering.add(other.velocity);

      total++;

      }

    }

    if(total > 0){

    steering.div(total);

    steering.setMag(this.maxSpeed);

    steering.sub(this.velocity);

    steering.limit(this.maxForce);

    }

        return steering;

  }

​

  cohesion(boids){

    let perceptionRadius = 100;

    let steering = createVector();

    let total = 0;

    for(let other of boids){

      let d = dist(this.position.x, this.position.y, this.position.z, other.position.x, other.position.y,other.position.z);

      if(other != this && d < perceptionRadius){

      steering.add(other.position);

      total++;

      }

    }

    if(total > 0){

    steering.div(total);

    steering.sub(this.position);

    steering.setMag(this.maxSpeed);

    steering.sub(this.velocity);  

    steering.limit(this.maxForce);

    }

        return steering;

  }  

​

  separation(boids){

    let perceptionRadius = 20;

    let steering = createVector();

    let total = 0;

    for(let other of boids){

      let d = dist(this.position.x, this.position.y, this.position.z, other.position.x, other.position.y,other.position.z);

      if(other != this && d < perceptionRadius){

      let diff = p5.Vector.sub(this.position, other.position);

      diff.div(d);

      steering.add(diff);

      total++;

      }

    }

    if(total > 0){

    steering.div(total);

    steering.setMag(this.maxSpeed);

    steering.sub(this.velocity);  

    steering.limit(this.maxForce);

    }

        return steering;

  }   

  flock(boids){

​

    let alignment = this.align(boids);

    let cohesion = this.cohesion(boids);  

    let separation = this.separation(boids);

    alignment.mult(alignSlider.value());

    cohesion.mult(cohesionSlider.value());

    separation.mult(separationSlider.value());    

    this.acceleration.add(alignment);

    this.acceleration.add(cohesion); 

    this.acceleration.add(separation);

  }

  update(){

    this.position.add(this.velocity);

    this.velocity.add(this.acceleration);

    this.velocity.limit(this.maxSpeed);

    this.acceleration.mult(0);    

  }

  border(){

    if(this.position.x > sizeX/2) this.position.x = -sizeX/2;

    if(this.position.x < -sizeX/2) this.position.x = sizeX/2;    

    if(this.position.y > sizeY/2) this.position.y = -sizeY/2;

    if(this.position.y < -sizeY/2) this.position.y = sizeY/2;

    if(this.position.z > sizeZ/2) this.position.z = -sizeZ/2;

    if(this.position.z < -sizeZ/2) this.position.z = sizeZ/2;     

  }

  show(){

    strokeWeight(this.sizing);

    stroke(this.coloring.x, this.coloring.y, this.coloring.z,200);

    point(this.position.x, this.position.y, this.position.z);

  }

}