What’s the legacy of Tron: Legacy? When it opened on Dec. 17, 2010, the big-budget Disney sequel was hypnotically watchable and maligned as a throwaway vehicle for a new Daft Punk record. But like the original 1982 Tron, a landmark of digital effects, it feels equally experimental in retrospect. Tron: Legacy is the peculiar and perhaps unwitting precursor to several practices that have come to define mainstream filmmaking up until now. And based on Disney’s current plans for the future, the blockbuster industry has no sign of slowing down. Set 28 years after the events of the first film, Tron: Legacy follows Sam (Garrett Hedlund), who discovers his father, Kevin Flynn (Jeff Bridges, returning from