- tetromino swapping
- sound effects
- level files & music timings
- fix thumbsticks
- scorekeeping/display
- victory (+animation)
- alternate clear animations

later:
- menu system
	- options (music/sfx volume)
- controller re-binding
- custom piece designs
- local multiplayer
- online multiplayer
- game modes:
	- survival (timed to music)
	- goal (lines cleared)
	- endless
	- fixed seed
- high scores (local, online)
- CRT shader?

https://tetris.fandom.com/wiki/Tetris_Guideline
https://tetris.fandom.com/wiki/SRS
https://tetris.fandom.com/wiki/TGM_Rotation

music sources:
	loops:
	https://opengameart.org/content/a-journey-awaits
	https://opengameart.org/content/snowfall
	https://opengameart.org/content/funny-chase-8-bit-chiptune
	https://opengameart.org/content/raining-beat-loop-8-bit-cyber-style-0
	https://opengameart.org/content/menu-music

	themes:
	https://opengameart.org/content/rise-of-spirit
	https://opengameart.org/content/menu-music
	https://opengameart.org/content/erdreich-des-h%C3%BCnchenvolk
	https://opengameart.org/content/acoustic-jazz

animation for concert opening:
- dark screen, one falling piece as the clarinet solo comes in
- when the rest of the band comes in, the rest of the level fades in