# Croquet

> Association Croquet played in the browser in true 3D, at the World Croquet Federation's own
> dimensions. The croquet stroke, four-ball break building, and hoops set with 0.8 mm of clearance.

https://croquet.skillsafe.ai/

## What it is

An independent reimplementation of Association Croquet — the codified two-ball-a-side game, not
garden croquet. Each side plays blue and black against red and yellow, and must make each of its
balls run twelve hoop points and hit the peg: 26 points a side (Law 1.1). It is single-player
against a computer opponent, runs entirely in the browser, makes no network requests after load,
and stores nothing but a preference for the hoop setting.

## What is faithful

The rules are the WCF *Laws of Association Croquet*, 7th Edition (24 January 2021), with the WCF
Equipment Regulations v6.4 and Sports Regulations v9.6. Every court dimension, the order and
direction of all twelve hoop points from Diagram 1, the roquet and croquet stroke, the continuation
stroke, the exact geometric definition of running a hoop, live and dead balls, the yard-line, the
wiring lift and the advanced-play lifts are implemented to the Law and cited by number in the
source. CREDITS.txt lists every one.

## The hoop, which is the point of the game

A ball is 92 mm across (Law 5.3.1). WCF Sports Regulation 8.1.2 requires a championship hoop to be
set so that the ball passes with "not less than 0.8 mm" of clearance in total — a quarter of the
1/8 inch that is usually quoted, which is a handicap-event setting rather than a championship one.
That fixes the largest angle at which a ball can run the hoop without touching, exactly:

    theta_max = arccos( rho / (rho + s) ),   rho = R + r,   s = c/2 - |d|

with R the ball's radius, r the upright's, c the clearance and d the offset at which the ball
crosses the hoop's plane. Dead centre that is 6.96 degrees at the championship setting and 13.73
degrees at a 3 3/4 inch club hoop. The app computes it live from wherever the ball lies, and the
setting is a player-chosen option across the whole range the Regulations allow.

## The croquet stroke

After a roquet the striker places their ball touching the roqueted ball and plays a stroke that must
move both (Laws 18.3, 18.5). The player chooses two destinations — one per ball — and the app
reports the split angle and distance ratio they demand and whether one stroke can deliver them. The
reachable band is calibrated to Don Gugan's published measurements of real strokes: a stop shot
sends the croqueted ball 5.64 times as far as the striker's, a drive 4.12, a full roll 1.24, a pass
roll 0.94.

## Files

- [Credits and sources](https://croquet.skillsafe.ai/CREDITS.txt): every Law cited, every published
  measurement used, and every number the app reconstructed because no source fixes it.
- [Licence](https://croquet.skillsafe.ai/LICENSE.txt): MIT.

## Not affiliated

This is an independent work built from public documents. It is not published by, endorsed by or
affiliated with the World Croquet Federation, Croquet England, or any other croquet body.