position.py

   1 # position.py
   2 # 1 Mar 2007
   3
   4 """
   5     This file is part of Arrocco, which is Copyright 2007 Thomas Plick
   6     (tomplick 'at' gmail.com).
   7
   8     Arrocco is free software; you can redistribute it and/or modify
   9     it under the terms of the GNU General Public License as published by
  10     the Free Software Foundation; either version 3 of the License, or
  11     (at your option) any later version.
  12
  13     Arrocco is distributed in the hope that it will be useful,
  14     but WITHOUT ANY WARRANTY; without even the implied warranty of
  15     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16     GNU General Public License for more details.
  17
  18     You should have received a copy of the GNU General Public License
  19     along with this program.  If not, see <http://www.gnu.org/licenses/>.
  20 """
  21
  22 import ctypes, time, threading, thread, copy, Queue
  23
  24 from lib import lib
  25 SIZE_OF_POSITION = lib.sizeOfPosition()
  26 c_int = ctypes.c_int
  27 c_short = ctypes.c_short
  28 int64 = ctypes.c_ulonglong
  29
  30 charForPiece = "  PpNnBbRrQqKk"
  31
  32 for r in range(8):
  33     for c in range(8):
  34         exec "%c%c = 8 * %d + %d" % ("abcdefgh"[c], "12345678"[r], r, c) in globals(), globals()
  35
  36
  37 class Position(ctypes.Structure):
  38     _fields_ = [("opaque", ctypes.c_byte * SIZE_OF_POSITION)]
  39
  40     def __init__(self):
  41         ctypes.Structure.__init__(self)
  42         self.offswitch = ctypes.c_int(0)
  43
  44     def getTurn(self): return lib.getTurn(ctypes.pointer(self))
  45     def setTurn(self, x): lib.setTurn(ctypes.pointer(self), x)
  46     turn = property(getTurn, setTurn)
  47
  48     def getValue(self): return lib.getValue(ctypes.pointer(self))
  49     def setValue(self, x): lib.setValue(ctypes.pointer(self), x)
  50     value = property(getValue, setValue)
  51
  52     def getBranch(self, i): return lib.getBranch(ctypes.byref(self), i)
  53
  54     def __getitem__(self, (r, c)):
  55         return lib.getPieceAt(ctypes.pointer(self), 8 * r + c)
  56
  57     def __setitem__(self, (r, c), v):
  58         lib.setPieceAt(ctypes.pointer(self), 8 * r + c, v)
  59         lib.calculatePositionValue(ctypes.byref(self))
  60
  61     def fen(self):
  62         def rowString(r):  return ''.join(charForPiece[self[r, c]] for c in range(8))
  63         boardString = '/'.join(rowString(r) for r in range(7, -1, -1)).replace(' ', '1')
  64         for i in range(8, 1, -1):  boardString = boardString.replace('1' * i, str(i))
  65         return "%s %s" % (boardString, ['w', 'b'][self.turn & 1])
  66
  67     def setFen(self, fen):
  68         parts = fen.split(" ") + ["w"]
  69         boardString, turn = parts[0:2]
  70
  71         boardString = boardString.replace('/', '') + (' ' * 64)
  72         for i in range(1, 9):  boardString = boardString.replace(str(i), ' ' * i)
  73         for n in range(64):
  74             r, c = divmod(n, 8)
  75             r = 7 - r
  76             piece = charForPiece.find(boardString[n])
  77             if piece < 0:  piece = 0
  78             self[r, c] = piece
  79
  80         lib.setTurn(ctypes.pointer(self), 0 if turn == 'w' else 1)
  81
  82     def __repr__(self):  return "position(%r)" % self.fen()
  83     def __str__(self):  return ''.join(self.display())
  84     def display(self):
  85         for r in reversed(range(8)):
  86             for c in range(8):
  87                 yield charForPiece[self[r, c]].replace(' ', '_')
  88             yield '\n'
  89
  90     def children(self):
  91         childArray = (Position * 512)()
  92         numberOfChildren = lib.makeChildren(ctypes.byref(self), ctypes.byref(childArray))
  93         return childArray[0:numberOfChildren]
  94     def legalChildren(self):
  95         return [child for child in self.children()
  96                     if not lib.inCheck(ctypes.byref(child), self.getTurn())]
  97
  98     def childrenGen(self):
  99         childArray = (Position * 512)()
 100         numberOfChildren = lib.makeChildren(ctypes.byref(self), ctypes.byref(childArray))
 101         i = 0
 102         for child in childArray:
 103             if i >= numberOfChildren:
 104                 break
 105             yield child
 106             i += 1
 107
 108
 109     def afterMove(self, sq1, sq2, promote=None):
 110         copy = Position()
 111         lib.afterMove(ctypes.byref(self), sq1, sq2, ctypes.byref(copy))
 112         return copy
 113
 114     def afterPass(self):
 115         copy = self.copy(); copy.turn ^= 1; return copy
 116
 117     def copy(self):
 118         copy = Position()
 119         ctypes.memmove(ctypes.byref(copy), ctypes.byref(self), SIZE_OF_POSITION)
 120         return copy
 121
 122     def __cmp__(self, other):  return cmp(self.fen(), other.fen())
 123     def __hash__(self): return hash(self.fen())
 124
 125     def unstop(self): self.offswitch.value = 0
 126     def stop(self):   self.offswitch.value = 1
 127
 128
 129 def position(s):
 130     pos = Position(); pos.setFen(s); return pos
 131
 132 allSquares = [(r, c) for r in range(8) for c in range(8)]
 133 def algebraicForPV(pv):
 134     def f((r, c)):  return "abcdefgh"[c] + "12345678"[r]
 135     def g(x):  return charForPiece[x].upper()
 136
 137     L = []
 138     while len(pv) > 1:
 139         parent, child = pv[:2]
 140         x = [sq for sq in allSquares if parent[sq] != child[sq]]
 141         try:
 142             if child[x[0]] > 0:
 143                 x.reverse()
 144             L.append(g(parent[x[0]]) + f(x[0]) + f(x[1]))
 145         except: break
 146
 147         pv = pv[1:]
 148     return L
 149
 150 ipos = position("rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq")
 151 pos12 = position("k7/8/KR")