For all the countless ways that J.K. Rowling’s evocative writing has determined the look and tone of the “Harry Potter’’ films, the directors who’ve adapted the books have certainly also significantly influenced the screen franchise’s development. Some of their choices have been made very deliberately, and reflect each filmmaker’s sensibility and vision. Other choices seem to have involved leaps of faith that simply worked out. And still others have been dictated by, as ever, budgets, or scheduling constraints, or the effects technology of the moment. (Ever notice how much more elaborately iconic the gothic sprawl of Hogwarts has grown over the span of a decade? So has the films’ production designer, Stuart Craig, who’s still sort of bugged by having had to go with the starter-home version on “Sorcerer’s Stone.’’)