// Daniel Shiffman

// http://natureofcode.com

//sketch NOC_6_02

​

​

// The "Vehicle" class

​

class Vehicle {

  constructor(x, y) {

    this.img = img;

    this.imgHeight = 1.5 * imgSize;

    this.imgWidth = 1 * imgSize;

​

    this.acceleration = createVector(0, 0);

    this.velocity = createVector(0, -2);

    this.position = createVector(x, y);

    this.r = 6;

    this.maxspeed = 5;

    this.maxforce = 5;

​

    this.system = new ParticleSystem();

​

​

  }

​

  // Method to update location

  update() {

    // Update velocity

    this.velocity.add(this.acceleration);

    // Limit speed

    this.velocity.limit(this.maxspeed);

    this.position.add(this.velocity);

    // Reset accelerationelertion to 0 each cycle

    this.acceleration.mult(0);

​

​

    // Should this code be in update?? Probably not.

    let gravity = createVector(0, 0.001);

    this.system.applyForce(gravity);

    this.system.run();

  }

​

  addParticle() {

​

​

    this.system.addParticle(this.position.x, this.position.y);

​

  }

​

  applyForce(force) {

    // We could add mass here if we want A = F / M

    this.acceleration.add(force);

  }

​

  // A method that calculates a steering force towards a target

  // STEER = DESIRED MINUS VELOCITY

  arrive(target) {

    var desired = p5.Vector.sub(target, this.position); // A vector pointing from the location to the target

    var d = desired.mag();

    // Scale with arbitrary damping within 100 pixels

    if (d < 100) {

      var m = map(d, 0, 100, 0, this.maxspeed);

      desired.setMag(m);

    } else {

      desired.setMag(this.maxspeed);

    }

​

    // Steering = Desired minus Velocity

    var steer = p5.Vector.sub(desired, this.velocity);

    steer.limit(this.maxforce); // Limit to maximum steering force

    this.applyForce(steer);

  }

​

  display() {

    // Draw an image rotated in the direction of velocity

    var theta = this.velocity.heading() + PI / 2;

    fill(127);

    stroke(200);

    strokeWeight(1);

    push();

    imageMode(CENTER);

    translate(this.position.x, this.position.y);

    rotate(theta);

    image(this.img, 0, 0, this.imgHeight, this.imgWidth);

    pop();

​

  }

}