update method

void update ()

Updates all visible, newly visible and not-visible-anymore Entity's. Also checks for collisions.

Implementation 

void update() async {
  this.visibleEntities.forEach((id, e) => e.update());
  this.addNewlyVisibleEntities();
  this.removeInvisibleEntities();
  this.updateDozerTailInVisibleEntities();
  this.checkCollisions();
  this._dozer.update();
}