https://github.com/greenlucid/chess-cairo

A Cairo contract to play chess in Starknet.
https://github.com/greenlucid/chess-cairo

cairo cairo-lang chess starknet

Last synced: 4 months ago
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A Cairo contract to play chess in Starknet.

• Host: GitHub
• URL: https://github.com/greenlucid/chess-cairo
• Owner: greenlucid
• Created: 2021-12-26T18:13:58.000Z (over 2 years ago)
• Default Branch: master
• Last Pushed: 2022-12-26T18:54:26.000Z (over 1 year ago)
• Last Synced: 2023-03-06T20:35:43.562Z (over 1 year ago)
• Topics: cairo, cairo-lang, chess, starknet
• Language: Cairo
• Homepage:
• Size: 319 KB
• Stars: 35
• Watchers: 3
• Forks: 4
• Open Issues: 1
• Metadata Files:
  • Readme: README.md

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• awesome-zero-knowledge-proofs - chess-cairo - A Cairo contract to play chess in Starknet

README

        
# chess.cairo

A Cairo contract to play chess, with composability in mind.

##  How it works

Every game of chess will be deployed in a single contract. Each contract has who plays as white, as black, who is the governor, and the initial fen state.

## State of chess

Because of threefold repetition, the full state of chess requires the full history of moves, so that any of the players can force a draw if a board state is reached three times. A **board state** is what is commonly referred to as the "state" of chess. That is, whatever can be represented with [Forsyth–Edwards Notation](https://en.wikipedia.org/wiki/Forsyth%E2%80%93Edwards_Notation), except the fullmove clock and the **halfmove clock** (count of plys since last irreversible action).

### Glossary of *states*

- **board state**: positions, active color, castling rights, passant.

- **fen state**: board state & halfmove clock & fullmove clock.

- **full state**: board state & halfmove clock & move history.

## How the state is stored

In chess.cairo, the contract keeps `initial_state`, an encoded fen state, and `moves`, the array of moves. That means, the contract effectively holds the full state. You can reach the current fen state by iterating through the move history, advancing move by move.

# Installation

This project uses [nile](https://github.com/OpenZeppelin/nile). Refer to it if you're lost. You'll also need pyenv, to use python3.7.

- `python3.7 -m venv env`

- `source env/bin/activate`

- `pip install git+https://github.com/OpenZeppelin/nile.git#egg=cairo-nile`

- `echo "WHITE=1234" > .env`

## Running it

Go to notes/useful_commands.txt to find some stuff. `{}` means you paste an address or a big hex.

- `source env/bin/activate` (do this in 2 terminals)

- `nile node`

- `nile setup WHITE`

- `nile compile contracts/chess.cairo`

- `nile deploy chess {white} {white} {white} {initial_fen}`

- `nile send WHITE {chess} make_move 13456 0`

If you got here you can figure out the rest yourself