Interactive music system

The interactive music system is a dynamic engine implemented by Retro Studios in Metroid Prime 3: Corruption. Scott Petersen described it as "simple in design" but "very complex in implementation" in an interview with Music4Games. All musical arrangements are defined in a spreadsheet, and this is interpreted at runtime. Every room in the game is assigned a default piece of music, such as the theme of the area, and ten music slots. However, the music is scripted by hand to change or transition based on events that are triggered in the room, or the state that Samus is in, according to Petersen. He cites as an example, a mini-boss encounter that occurs after Samus obtains the Ship Grapple Beam and returns to a previous room. Some rooms are simpler to script music for, while others that are the site of events are more complex. An option to adjust the in-game music's volume based on static multipliers or a spine was added, allowing the volume of music and sound effects to temporarily dim when speaking to a non-player character, or at the beginning or end of a cutscene.