Renju Library (五子棋/连珠棋盘库)

English | 中文

English

A simple, lightweight Python library for representing, managing, and visualizing a Renju / Gomoku (五子棋) game board, verifying game state rules, performing symmetry transformations, and detecting symmetric candidate moves.

Features

• Rules & Forbidden Moves (Renju, Standard, Freestyle): Full referee rules logic integrated. Automatically checks for win conditions and Black forbidden moves (Double-three, Double-four, Overline) according to rule sets.
• Win Reason Reporting: Returns both the BoardStatus and the specific WinReason (e.g. five-in-a-row, double-three forbid) after every move.
• Candidate Symmetry Grouping: Evaluates whether any candidate coordinates, when added to the existing board layout, result in symmetric layouts. The algorithm is translation-invariant (ignores distance to board boundaries), rotation-invariant, and reflection-invariant. Essential for validating five-hand N-point plays (五手N打).
• Pass Move Support: Supports passing a turn (skipping placement) represented internally as coordinate [-1, -1] and string format as "pass". Consecutive passes by both players results in a draw.
• Bespoke Board Coordinates: Easily convert between 0-based integer coordinates (x, y) and standard Excel-style string coordinates (e.g. (7, 7) $\leftrightarrow$ "h8").
• Flexible Parser: Parse move sequences from clean strings (e.g., "h8i9g7", "h8passi9") or separator-formatted sequences as well as coordinate lists.
• Interactive Play & Undo: Dynamically play moves with play_move or play_str, check the current turn player, and undo moves (which recalculates the rules state).
• Symmetry Transformations: Dihedral group of 8 square board transformations (copy, flip_x, flip_y, flip_diagonal, flip_anti_diagonal, rotate_90, rotate_90_ccw, rotate_180) returning new transformed RenjuBoard instances.
• Equivalence & Isomorphism Check: Check exact equality of two boards (==) or whether two boards are isomorphic/equivalent under any of the 8 symmetries (is_symmetric_to).
• Terminal Board Visualization: High fidelity board printing representation (__str__ / display()) showing current black (X) and white (O) positions with custom grids.
• SGF Import & Export: Serializes and parses game logs to/from standard SGF (Smart Game Format, GM[4]), correctly preserving player names, dates, results, rules, and pass moves.

Installation

pip install renju

Quick Start

from renju import RenjuBoard, Rule, BoardStatus, WinReason

# 1. Initialize board (size 15x15) with Renju rule set
board = RenjuBoard(board_size=15, rule=Rule.RENJU)

# 2. Dynamic plays & rules checking (returns status, reason)
status, reason = board.play_move(7, 7) # play h8
print(status)  # Output: BoardStatus.ONGOING

# 3. Find symmetric candidate moves (useful for N-point plays validation)
# Existing configuration: vertical line (h8, h9, h7, h6)
board_line = RenjuBoard(pos="h8h9h7h6")
# Candidates: i8(8,7) and i7(8,6)
candidates = [(8, 7), (8, 6), (9, 9)]
symmetric_groups, all_groups = board_line.find_symmetric_candidates(candidates)

print(symmetric_groups) # Output: [[(8, 7), (8, 6)]] -> i8 and i7 are symmetric configurations!
print(all_groups)       # Output: [[(8, 7), (8, 6)], [(9, 9)]]

# 4. Pass support
status, reason = board.play_move(-1, -1) # B passes

# 5. Undo restores board and recalculates game state
board.undo()

# 6. Display the board in terminal
board.display()

# 7. SGF Export & Import
sgf_string = board.to_sgf(black_name="Alice", white_name="Bob", date="2026-06-07")
imported_board = RenjuBoard.from_sgf(sgf_string)

中文

一个轻量级的 Python 库，用于表示、管理和可视化连珠/五子棋（Renju / Gomoku）的棋盘状态和落子序列，并支持游戏规则校验、对称变换及候选等价点查找。

主要功能

• 规则与禁手校验（连珠、标准、自由规则）：内置裁判规则引擎，自动判定胜负以及黑棋禁手（三三禁手、四四禁手、长连禁手）。五连与禁手同时出现时，优先判定五连获胜。
• 返回获胜原因：每次落子后都会返回包含当前棋局状态 BoardStatus 和具体原因 WinReason 的元组。
• 打点对称等价性判定（平移、旋转、翻转无关）：输入多个坐标，判断这些点与棋盘已有棋局组合后是否有部分对称（同构）。算法消除了棋形到盘端距离的差异（平移无关），且支持 8 个角度的翻转/旋转检测。此算法特别适用于五手N打（五手多打）的非法对称打点校验。
• Pass（过牌/不落子）支持：支持略过一手棋。在坐标序列中以 [-1, -1] 表示，字符串表示为 "pass"。若双方连续过牌，判定为和棋。
• 优雅的坐标转换：轻松在从 0 开始的整型坐标 (x, y) 与标准的字母数字棋盘坐标之间进行双向转换。
• 灵活的落子序列解析：支持直接通过连贯的字符串（如 "h8i9g7"、"h8passi9"）、带分隔符的文本或坐标对列表来初始化棋盘。
• 交互式对弈与悔棋：提供 play_move、play_str 与 undo 方法。悔棋时会自动重新计算并恢复到历史棋局对应的正确规则状态。
• 对称变换：内置 8 种棋盘对称与旋转操作，且能正确处理过牌步。
• 等价性与同构性检查：支持直接通过 == 检查两棋盘是否完全一致，或使用 is_symmetric_to 检查两棋盘在旋转/镜像变换后是否等价（同构）。
• 棋盘可视化：能够在终端直接绘制出直观的棋盘（黑棋为 X，白棋为 O，空位为 .，自动跳过过牌步）。
• SGF 棋谱导入与导出：支持标准 SGF（Smart Game Format）棋谱格式的读取与保存，支持记录对局信息（如棋手名字、对局日期、胜负结果及具体原因等），完美支持过牌（Pass）步骤的解析与还原。

安装方式

pip install renju

快速上手

from renju import RenjuBoard, Rule, BoardStatus, WinReason

# 1. 初始化一个 15x15 的连珠规则棋盘
board = RenjuBoard(board_size=15, rule=Rule.RENJU)

# 2. 动态落子与规则状态获取
status, reason = board.play_move(7, 7) # 在 h8 落子
print(status)  # 输出: BoardStatus.ONGOING

# 3. 查找对称打点（五手N打校验）
# 现有棋局：垂直的一条四连线：h8(7,7), h9(7,8), h7(7,6), h6(7,5)
board_line = RenjuBoard(pos="h8h9h7h6")
# 给定打点坐标：i8(8,7)、i7(8,6) 和 j10(9,9)
candidates = [(8, 7), (8, 6), (9, 9)]
symmetric_groups, all_groups = board_line.find_symmetric_candidates(candidates)

print(symmetric_groups) # 输出: [[(8, 7), (8, 6)]] -> i8 和 i7 生成的棋形对称！
print(all_groups)       # 输出: [[(8, 7), (8, 6)], [(9, 9)]]

# 4. Pass 过牌支持
status, reason = board.play_move(-1, -1) # 黑棋过牌

# 5. 悔棋将自动重新计算并恢复棋局状态
board.undo()

# 6. 在控制台打印可视化棋盘
board.display()

# 7. SGF 棋谱导入与导出
sgf_string = board.to_sgf(black_name="Alice", white_name="Bob", date="2026-06-07")
imported_board = RenjuBoard.from_sgf(sgf_string)