LOS ANGELES — If you asked the auteur film director Gus Van Sant how long he has been painting, he might tell you about winning first prize at the annual art show in his hometown Darien, Conn., when he was 12. He might relate the influence of Jackson Pollock on his style as an 8-year-old. (It wasn’t such a big deal, he’d say. “It was really just because you could throw paint and that was a painting.”) He might even explain how, as a dual painting and film major at the Rhode Island School of Design, he dropped the art course because film “was harder, and I just didn’t know about it. I knew about painting.”