Rhythm Game

Make a chart that feels like the song, not a metronome.

What the user gets

Rules this entry enforces

• Track first, chart second. The chart is derived from the audio's onsets, never written before the music exists.
• Fixed BPM. Generated music is requested at a stated BPM; the file is checked; drift over 0.5 BPM is rejected.
• Density follows structure. Verse sparse, build rising, drop dense, outro release. A flat-density chart is a typing test.
• Notes on accents, not on every beat. The chart plays what the ear hears.
• Timing windows are stated in ms. perfect ±40 · good ±90 · miss beyond.
• Hit effects obey causality. The effect fires on the hit, in the lane, with the note's colour — same rule as vfx-effect.
• Difficulty tiers share the song. Easy is a subset of normal; normal a subset of hard.

Example

Track: 128 BPM, 90 s, "amber pulse" — intro 8 bars · verse 16 · build 8 ·
drop 16 · outro 8; instrumental, no vocals
Chart (normal): verse 1 note/beat on kick · build adds hats every half-beat ·
     drop 2–3 notes/beat with holds on the synth stabs · outro 1/2 beat
Lanes: 4 · notes as lantern sparks · hit = amber ring · miss = fog puff
Windows: ±40 / ±90 ms

Related entries

• film-generate-review (core) — music generation happens in its audio pass
• vfx-effect — hit effects
• pixel-art-sprite — note and lane sprites