# Badminton

> A true 3D singles badminton match in the browser, played under the BWF Laws of Badminton,
> with a shuttlecock modelled as what it actually is: a high-drag, self-orienting body that
> flips cork-first within a fifth of a metre of the racket and then stalls.

URL: https://badminton.skillsafe.ai/

## What it is
Singles badminton, best of three games to 21, rally scoring. Hand-written WebGL2, no
libraries, no network calls, no accounts. The engine is pure, deterministic and seeded.

## What is faithful
- Court, net and every line at BWF Diagram A dimensions: 13.400 m x 6.100 m (5.180 m singles),
  40 mm lines, net 1.524 m at the centre and 1.550 m at the posts, 760 mm deep.
- Law 1.3: all lines form part of the area they define, so touching a line is IN.
- Laws 10.1.1/10.1.2: the service court follows the SERVER's own score parity.
- Laws 7.2/7.4/7.5: 21, two clear at 20-all, hard cap at 30.
- Law 8.1: ends change after each game and at 11 in the third.
- Law 9.1.6: service contact below 1.15 m.
- Law 3: the shuttle speed test reproduces, landing 760 mm short of the far back boundary line.

## The physics
The shuttle's position, velocity, body axis and angular velocity are integrated together by a
single RK4 over the whole 12-dimensional state; the measured convergence order is 3.91, and a
control that splits the orientation off the step measures 1.33. The drag area is derived from
the Law 3 band rather than chosen, and the band pins terminal velocity to 6.63-6.79 m/s.

## Files
- /            the game
- /CREDITS.txt sources, what is reconstructed, and what differs from the sport
- /LICENSE.txt MIT

## Not affiliated
Badminton is a sport; nobody owns it. The Laws are the Badminton World Federation's. This is an
independent implementation and is not endorsed by the BWF.