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Bullseye Rivals

Darts with 501, checkout and practice modes against three CPU levels.

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Games: 501 with a double out, checkout, practice
CPU: Amateur, Club, Pro
Controls: Pull and release, or flick
Engine: three.js, custom throw model

About the game

Single-player
Versus AI

Bullseye Rivals is darts in the browser: 501 with a double out, a checkout challenge and a practice mode. Play the computer at Amateur, Club or Pro level.

Throws use our own throw model. On desktop you pull back and release, on a touch screen you flick. An announcer and crowd call the game, with replays for the big scores.

A throw model, not a random number

The engineering

A dart does not land where a random number says it should. Bullseye Rivals has its own throw model, and your pull-back and release (or your flick, on a touch screen) become the dart's flight. The CPU opponents miss in the same way you do, with aim and speed noise that grows from Pro down to Amateur.

The code is organised with a pure core (the board, the 501 rules, checkouts, the throw model, physics and the AI) kept apart from the client, with 96 automated tests around it. three.js is vendored with no bundler. The core is kept free of browser code, and a test enforces that, so the same code could run on a server one day. There is no server today: scoring happens in the browser.

The look and feel

A dartboard on the wall of a green-walled room, with a scoreboard that keeps you honest and a crowd that reacts. The checkout challenge and the practice mode give you something to do when you want to improve rather than just play.

It is a single-player game against the computer: no online play and no accounts.

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