this.x = random(windowWidth);

  this.y = random(windowHeight);

  this.lastX = this.x;

  this.lastY = this.y;

}

​

Agent.prototype.draw = function() {

  //fill(random(255), random(255), random(255));

    // ellipse(this.x, this.y, 40, 40);

  stroke(90, 50);

  line(this.lastX, this.lastY, this.x, this.y);

  this.lastX = this.x;

  this.lastY = this.y;

  this.x = this.x + random(10) - 5;

  this.y = this.y + random(10) - 5;

}