ChessEngine

ChessEngine is a modular chess application designed for playing and experimenting with chess. It includes a graphical user interface (GUI), a logic-based chessboard implementation using bitboards, and an evolving chess bot for computer play.

Features

• Chess GUI: A visually appealing interface for playing chess, built using SDL2 and SDL2_image.
• Chess Logic: Implements chess game mechanics using an efficient bitboard representation.
• Chess Bot: An AI player (under development) to play against the user.
• SOLID Principles: The project design adheres to SOLID principles for maintainable, scalable, and modular code.

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Project Structure

The project is organized into the following directories:

1. chessBoard

Contains the core logic of the chess game, utilizing bitboards for efficient representation and computation of moves. It includes:

• Move validation
• Game state management
• Board representation

2. chessGUI

Handles the graphical user interface for the chess game. Built using:

• SDL2: For rendering the chessboard and pieces.
• SDL2_image: For managing images of chess pieces.
• It includes a CMakeLists.txt file for building the GUI component.

3. chessBot

An AI opponent that plays against the user. Implemented with:

• Negamax alpha-beta search with iterative deepening, quiescence, MVV-LVA move ordering, and a transposition table
• Heuristic evaluation: material, tapered piece-square tables, mobility, king safety, and pawn structure
• A bot CLI (bot "<fen>" --ms 1000) and a bot_suite test target
• Playable in the GUI (keys 1/2/3 choose human-vs-human or which side the AI plays)

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Design Philosophy

This project adheres to the SOLID principles to ensure:

• Single Responsibility: Each module handles a distinct responsibility (e.g., GUI, logic, AI).
• Open/Closed: Components are designed to allow extension without modifying existing code.
• Liskov Substitution: Abstract interfaces are used to enable interchangeability between components.
• Interface Segregation: Components interact through minimal, role-specific interfaces.
• Dependency Inversion: High-level modules depend on abstractions, not low-level implementations.

By following these principles, the project aims to remain maintainable, scalable, and testable as it evolves.

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Requirements

To build and run ChessEngine, ensure the following dependencies are installed:

General

• CMake: For building the project.

GUI Requirements

• SDL2
• SDL2_image
• SDL2_ttf (for the on-board result banner)

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Building the Project

1. Clone the repository:

   git clone https://github.com/subarnasaikia/ChessEngine.git
   cd ChessEngine

2. Build the chessGUI module:

   cd chessGUI
   mkdir build
   cd build
   cmake ..
   make

3. Run the GUI executable:

   ./ChessGUI

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Usage

• Launch the GUI to start a new game.
• Press 1 for human-vs-human, 2 to play White against the AI, or 3 to play Black against the AI. F5 starts a new game.
• Move by clicking a piece then its destination, or by dragging.

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Roadmap

• Run the bot's search on a background thread so the GUI stays responsive while it thinks.
• Strengthen the bot (opening book, deeper/smarter search, evaluation tuning).
• Improve GUI visuals and responsiveness.

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License

This project is licensed under the MIT License.