okay this is sick as hell. when i decide to make a music mod i wanna try to incporporate this.

Pikmin 2 cave music in terraria!?

Here's a complete, but simple track: https://github.com/Tyfyter/OriginsMusic/blob/main/Music/Mildewy_Situation.json
Here's the different types of keyframes: https://github.com/Tyfyter/ProceduralMusicLib/blob/1fb6ed2a1fadd11908a597106d34a9a07d11e6de/JSONAudioTrack.cs#L106-L109
And these methods or the SetTrigger mod call can be used to make music dynamic: https://github.com/Tyfyter/ProceduralMusicLib/blob/1fb6ed2a1fadd11908a597106d34a9a07d11e6de/ProceduralMusicLib.cs#L411-L420

If you don't mind can you link an example, docs, or something?

finally, we can have accurate rain world music in (modded) terraria.