Photo: Courtesy of 20th Century Studios “I only have three or four great ideas, and I just keep repackaging them,” James Cameron observes in Tech Noir: The Art of James Cameron, a fancy coffee-table book of the 68-year-old Academy Award–winning filmmaker’s sketches and paintings dating back to his tween years. On one page, we see an alien landscape of exotic and luminous vegetation Cameron drew in the late ’70s when he was trying to get funding for a feature-length version of his sci-fi short Xenogenesis. That project would go unrealized but clearly inspired both his 1986 sequel Aliens and the...