Rookie guard Coby White’s first Summer League in Las Vegas was a nightmare. His decision-making at level guard was questionable, and his three-point capturing was an atrocious 3-for-30. The response from White and the Bulls on the time? It’s simply the Summer League. White’s first NBA preseason was a showcase. His three-point capturing was a deadly 43.2 %, and the pace he confirmed at North Carolina was usually in proof. So what does White take into consideration his first preseason? ‘‘I mean, it’s simply preseason,’’ he stated after a 29-point efficiency within the Bulls’ victory Thursday towards the Hawks on the United Center. That’s what coach Jim Boylen loves about White: He’s by no means happy.