A Framework for Board Games - Part I

This post provides a framework which can implement various turn based (human Vs computer) board games such as Tic-Tac-Tao and Connect 4. In this Part I, a structure of the overall logic for a game is given. The program can ask for move from human, and will get its moves by random, it also knows whether the game is ended or not by checking a set of ending rules. In Part II, a tree searching algorithm for determining the moves of the computer is presented. With that intelligence, the computer will act like an expert player and can beat all human in theory.

1. The game Tic-Tac-Tao is choosen for demonstration.
2. The game is run in console mode, only a minimal graphics composed by text is included.
3. Two Python classes are used to represent the players' states and the game itself.
4. The set operations provided by Python are employed to determine whether the game is ended.

Source Code

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# Title : Tic-Tac-Tao # : computer choose move by random # Date : 10/08/2019 # Version : 0.1 # # Remarks: # 1. Positions for the slots on # the board # 1 | 2 | 3 # ---|---|---- # 4 | 5 | 6 # ---|---|---- # 7 | 8 | 9 # 2. human(O), computer(X), free( ) # 3. Rules for wining: # [1,2,3],[4,5,6],[7,8,9],[1,4,7], # [2,5,8],[3,6,9],[1,5,9],[3,5,7] # import random class players: def __init__(self): self.freeSlots = range(1,10) self.human = [] self.computer = [] self.turn = 'c' def humanMove(self,pMove): if pMove in self.freeSlots: self.freeSlots.remove(pMove) self.human.append(pMove) self.turn = 'c' def computerMove(self,pMove): if pMove in self.freeSlots: self.freeSlots.remove(pMove) self.computer.append(pMove) self.turn = 'h' class boardgame: def __init__(self): self.icons = [' ','O','X'] self.players = players() def printBoard(self): mBoard = [] for mi in range(1,10): if mi in self.players.freeSlots: mBoard.append(self.icons[0]) elif mi in self.players.human: mBoard.append(self.icons[1]) else: mBoard.append(self.icons[2]) mr = '' mbar = ' ---|---|---\n' mr = ' %s | %s | %s\n' % tuple(mBoard[0:3]) mr += mbar mr += ' %s | %s | %s\n' % tuple(mBoard[3:6]) mr += mbar mr += ' %s | %s | %s\n' % tuple(mBoard[6:9]) print print mr # determine whether the game # is ended or not # return # d - draw # h - human win # c - computer win # n - not yet ended def endGame(self): mrules = [[1,2,3],[4,5,6],[7,8,9],[1,4,7], [2,5,8],[3,6,9],[1,5,9],[3,5,7]] mret = 'n' # determine who win for mi in mrules: # computer win? mrs = set(mi) if mrs.issubset( set(self.players.computer)): mret = 'c' break if mret == 'n': # human win? for mi in mrules: mrs = set(mi) if mrs.issubset( set(self.players.human)): mret = 'h' break if mret == 'n': # draw? if len(self.players.freeSlots)==0: mret = 'd' return mret # determine the next move # return the position of the next move # x - 1, 2, ... 9 def nextMove(pGame): # random move mpos = random.choice(pGame.players.freeSlots) return mpos # main mgame = boardgame() mgame.players.turn = random.choice(['c','h']) if mgame.players.turn=='h': mgame.printBoard() # the turn based game loop while mgame.endGame() == 'n': if mgame.players.turn=='h': # human's turn mfree = mgame.players.freeSlots ms = 'Your turn [' for mi in mfree: ms += str(mi) + ', ' ms = ms[:-2]+'] ? ' mpos = input(ms) if not mpos in mfree: continue mgame.players.humanMove(mpos) else: # computer's turn # next move mpos = nextMove(mgame) # random move print 'Computer chooses %s' % (mpos) mgame.players.computerMove(mpos) mgame.printBoard() print # print result print mgame.printBoard() if mgame.endGame() == 'h': print 'Human wins!' elif mgame.endGame() == 'c': print 'Computer wins!' elif mgame.endGame() == 'd': print 'Draw!'

Test Run

Computer chooses 8

     |   |  
  ---|---|---
     |   |  
  ---|---|---
     | X |  


Your turn [1, 2, 3, 4, 5, 6, 7, 9] ? 2

     | O |  
  ---|---|---
     |   |  
  ---|---|---
     | X |  


Computer chooses 5

     | O |  
  ---|---|---
     | X |  
  ---|---|---
     | X |  


Your turn [1, 3, 4, 6, 7, 9] ? 1

   O | O |  
  ---|---|---
     | X |  
  ---|---|---
     | X |  


Computer chooses 3

   O | O | X
  ---|---|---
     | X |  
  ---|---|---
     | X |  


Your turn [4, 6, 7, 9] ? 7

   O | O | X
  ---|---|---
     | X |  
  ---|---|---
   O | X |  


Computer chooses 9

   O | O | X
  ---|---|---
     | X |  
  ---|---|---
   O | X | X


Your turn [4, 6] ? 4

   O | O | X
  ---|---|---
   O | X |  
  ---|---|---
   O | X | X




   O | O | X
  ---|---|---
   O | X |  
  ---|---|---
   O | X | X

Human wins!