/chess

A ruby command-line chess game.

Primary LanguageRuby

Ruby Chess Game

This game is the capstone project for The Odin Project's Ruby Programming curriculum.

Demo

demo gif of classic 1858 game of Paul Morphy vs Duke Karl

A short demonstration of The Opera Game, a famous 1858 match between Paul Morphy and Duke Karl.

How to Play

For best visual results, install locally and play around with fonts that look good with the chess board. The demo above uses Noto Mono Regular in 14pt font. To just get a sense of the gameplay, play online using link below.

Play Online

Play quickly and easily on this replit.com page. After page loads, click the green "run" button. After a few seconds of loading, you should be on the welcome screen.

Install Locally

Requirements

  • ruby >= 2.7.0
  • bundler >= 2.1.2

Installation

  • clone this repo
  • cd into cloned directory cd chess
  • run bundle install

Running the Tests

To run the tests

  • rspec spec/ from the chess directory.

How to Play

  • run ruby lib/main.rb
  • make a selection on the welcome screen

Gameplay

At the welcome screen, you'll be prompted to select a game mode. Your choices are

  1. play a friend
  2. play the computer (computer makes a random move or capture)
  3. play a saved game

During any player move, you have commands available to you.

commands: flip | save | load | help | quit | resign | draw

  • flip - switches the view to the opposite board perspective
  • save - saves game with filename of your choice. resumes progress after saving
  • load - exits current game and loads a selected saved game
  • help - shows the help screen
  • resign - current player forfeits the match
  • draw - current player can offer a draw. CPU will always decline (It's easy to beat!)
  • quit - terminates the program

How to move pieces

This game uses traditional algebraic notation to enter moves. Attack moves must preface destination square with an "x".

Every piece except the pawn is assigned a piece prefix:

King, Queen, Rook, Knight, Bishop == K, Q, R, N, B

  • pawns => e5, exd6, a5, axb6 . . .
  • others => Ke7, Kxe7, Nc3, Nxc6 . . .
  • castling => 0-0 (king-side). 0-0-0 (queen-side)
  • en passant => exd6 (attack as if enemy has just moved one square)

Moves are case sensitive.

Move Disambiguation
  • If disambiguation is required (two or more pieces of the same type can go to the same square), you'll be prompted to choose which piece you'd like to move.
Pawn Promotion
  • If one of your pawns reaches its final rank, you will be prompted to promote it to either a Queen, Rook, Knight, or Bishop
En Passant Attacks
  • Follows en passant rules. Only possible if most recent enemy move was a two-square pawn move
Castling

Castling is only possible if the following are true:

  • Your King is not currently in check
  • Neither your King nor your relevant Rook has moved previously
  • No opponent pieces can attack your King's castling path.
Checkmate and Stalemate
  • Checkmate => A player has no legal moves and their king is in check.
  • Stalemate => A player has no legal moves and their king is not in check.
  • Game will conclude upon either stalemate or checkmate

TODO

  • Learn more about OOP and design patterns.