Scoring system

Timing windows

Provided that a frame is 16.73322954 ms long, these are the timing windows the game use:

• [0, 3] frames: PERFECT
• [3, 5] frames: GOOD
• [5, 7] frames: BAD
• [7, 9] frames: MISS

The windows are the same if the player presses a note before or after its time.

Combo

• Each note adds 1 to the current combo.
• Notes with more than one arrow (e.g. doubles) only count by 1.
• GOODs doesn't add combo.
• BADs and MISSes break combo.
• Hold notes create only PERFECTs or MISSes, one per tick.
  • The amount of ticks depends on the song part, specifically in the TICKCOUNTS segment.
  • There's always one tick at the arrow's head and one tick at the arrow's tail.

Points

Base points per note:

• PERFECT: 1000
• GREAT: 500
• GOOD: 100
• BAD: -200
• MISS: -500

If your combo is > 50 and you got a perfect or great, add 1000.

Dance grade

percent = (
  perfects * 1.2
  + greats * 0.9
  + goods * 0.6
  - bads * 0.45
  - misses * 0.9
  - longNotes * 0.2
  + maxCombo * 0.05
) / totalNotes

if (percent >= 0.95 && good + bad + miss == 0)
  "SS"
else if (percent >= 0.95 && miss == 0)
  "S"
else if (percent >= 0.95)
  "A"
else if (percent >= 0.90)
  "B"
else if (percent >= 0.85)
  "C"
else if (percent >= 0.75)
  "D"
else
  "F"