In a movie the scene is locked. When somebody says we want to build this music logic system and we don't know if the character's going to go here or there, or support or betray this person, how do you wrap your head around composing flexible music?
TL;DRZanelli writes music in pieces that can transition at any point, so the engine can switch between versions such as grim, heroic or ambient depending on what is happening to the player.
Well, and it is different, right? Because there isn't a version of E.T. where he doesn't go home and no one had to write that music, right? But in this case, we know certain things most likely will happen, but we also don't know when they're going to happen. That's another thing. But what I did really was with the music logic systems, let's say you're flying a ship. And you're in combat, right? But that can mean a lot of different things. There can be two enemies, there can be ten, there can be none, they can be right around the corner. So those are all different pieces of music, but they're written in such a way that they can transition at any point from one to the next, and the game engine can keep track of what's happening to the player. Did the bad guy come out? Are you outnumbered? Are you injured? Are you winning? Are you losing? And it can switch into and out of a grim version of the same music, a heroic version, a more ambient version. And this exists for all sorts of different levels, game states. Is it a more epic scene? Is it more intimate? Is it hand-to-hand combat? Is it EVA?