The intention was to give an idea of what the most common velocity of
the beatmap is, but in hindsight, because the "base" velocity is being
set elsewhere this doesn't make sense. It will/should be 1.0x.
Showing this range is still valuable, though.
This fixes two issues the previous algorithm had:
1. A half-turn rotation used to show up as -180°.
2. Rotating more than 180° in one drag event would overwhelm it
and cause the value to go outside its range.
This comes at the cost of a negligible performance hit,
since a division (modulo) is performed instead of just addition/subtraction.