Gary Whitta, writer of Rogue One, is always dropping little nuggets for Star Wars fans on his Twitter account. Today, Gary showed off the drawing that inspired the scene in Rogue One when the Death Star sheers off the top of the Scarif transmission tower and kills all of our heroes (and Director Krennic).
I would agree with Gary when he says that ILM did a much better job than he did on the whiteboard in his office. It goes to show that visual effects artists are truly magicians.