python+pygame实现五子棋人机对战之三

上回讲过：

python+pygame实现五子棋人机对战之一

python+pygame实现五子棋人机对战之二

界面已经有了，并且可以支持鼠标操作选择菜单和人机对战开始下棋了，那电脑是如何应手落子呢？以下内容是通用的类，全部放在utils.py中

四、

最常见的基本棋型大体有以下几种：连五，活四，冲四，活三，眠三，活二，眠二了，下面简要讲解一下：

4.1 连五：五颗同色棋子连在一起

4.2 活四：由4枚同色棋子形成的两端没有对方棋子的四枚棋子

4.3 冲四一（连四）：由4枚同色棋子形成的一端有对方棋子的四枚棋子

4.4 冲四二（跳四）：由4枚同色棋子形成的中间没有对方棋子的四枚棋子。

4.5 眠四：由4枚同色棋子形成的两端有对方棋子的4枚棋子。不能成五的四连。

相对比活四来说，冲四的威胁性就小了很多，此时，防守方只要跟着防守在那个唯一的连五点上，冲四就没法形成连五。

4.6 活三一（连三）：由3枚同色棋子形成连三、跳三。再走一着可以形成活四的三。两端都是威胁的活三。简称“连三”。

4.7 活三二（跳三）：由3枚同色棋子形成的中间没有对方棋子的三枚棋子。中间夹有一个威胁的活三。简称“跳三”。

4.8 眠三：由3枚同色棋子形成的两端有对方棋子的3枚棋子。即再走一着可以形成冲四的三。眠三的形状是很丰富的。眠三的棋型与活三的棋型相比，危险系数下降不少，因为眠三棋型即使不去防守，下一手它也只能形成冲四，而对于单纯的冲四棋型，我们是可以防守住的。

活三可以形成眠三，但也能够形成活四。眠三只能够形成冲四。

4.9 活二：由2枚同色棋子形成的连二（由2枚同色棋子连在一起形成的两头没有对方棋子的2枚棋子。）、跳二（由2枚同色棋子形成的中间没有对方棋子的2枚棋子。）、大跳二（中间有两个空白位置的跳二）。

4.10 眠二：由2枚同色棋子形成的两端有对方棋子的2枚棋子。是能够形成眠三的二。

对于棋盘上每一个交叉点，会有8个方向连成五子的可能性，那么我们就利用算法算出所有的可能性，并根据它成五的概率给它打分，这样，得分最高的就是最好的落子点。

如何去实现呢？首先我们在8个方向上将其抽象成坐标的加减，例如水平向右，那么x+1，y不变，向右上，则x+1，y+1 .按正下方开始，逆时针8个方向就形成下面的数据结构：

directions = [[0, 1], [1, 1], [1, 0], [1, -1], [0, -1], [-1, -1], [-1, 0], [-1, 1]]

获取当前坐标的各个方向上棋子属性，返回1代表白棋，返回2代表黑棋，返回0代表没有棋，返回5表示在棋盘外。

from params import Paramsrows = int(Params.get('ROWS'))
blocksize = int(Params.get('blockSize'))
width = int(Params.get('WIDTH'))
height = int(Params.get('HEIGHT'))# 获取当前坐标的各个方向上棋子属性，返回1代表白棋，返回2代表黑棋，返回0代表没有棋，返回5表示在棋盘外
def getpointpiece(_mapchess,pos, src, offset):# 8个方向directions = [[0, 1], [1, 1], [1, 0], [1, -1], [0, -1], [-1, -1], [-1, 0], [-1, 1]]x1, y1 = posx1 = x1 + directions[src - 1][0] * offset * blocksizey1 = y1 + directions[src - 1][1] * offset * blocksizeif x1 > 588 or y1 > 588 or x1 < 28 or y1 < 28:return 5else:return _mapchess[str(x1) + ',' + str(y1)]

再加上刚才分析的五子棋的基本棋型，可以设计出一个打分算法：

from params import Paramsrows = int(Params.get('ROWS'))
blocksize = int(Params.get('blockSize'))
width = int(Params.get('WIDTH'))
height = int(Params.get('HEIGHT'))# 判断每个点的value，用来排序该点下棋的可行性
def pointvalue(_mapchess, pos, flag1, flag2):value = 0    #加权值for i in range(1, 9):  #8个方向# 11111   连五if getpointpiece(_mapchess,pos, i, 1) == flag1 and \getpointpiece(_mapchess,pos, i, 2) == flag1 and \getpointpiece(_mapchess,pos, i, 3) == flag1 and \getpointpiece(_mapchess,pos, i, 4) == flag1 and \getpointpiece(_mapchess,pos, i, 5) == flag1:value += 1000000# *1111_ 活四if getpointpiece(_mapchess, pos, i, 1) == flag1 and \getpointpiece(_mapchess, pos, i, 2) == flag1 and \getpointpiece(_mapchess, pos, i, 3) == flag1 and \getpointpiece(_mapchess, pos, i, 4) == flag1 and \getpointpiece(_mapchess, pos, i, 5) == 0:value += 50000# *11112 冲四1，冲四指加一个点就是连五，比活四威力小得多if getpointpiece(_mapchess, pos, i, 1) == flag1 and \getpointpiece(_mapchess, pos, i, 2) == flag1 and \getpointpiece(_mapchess, pos, i, 3) == flag1 and \getpointpiece(_mapchess, pos, i, 4) == flag1 and \getpointpiece(_mapchess, pos, i, 5) == flag2:value += 30000# 1*111 冲四2if getpointpiece(_mapchess, pos, i, -1) == flag1 and \getpointpiece(_mapchess, pos, i, 1) == flag1 and \getpointpiece(_mapchess, pos, i, 2) == flag1 and \getpointpiece(_mapchess, pos, i, 3) == flag1:value += 30000# 11*11 冲四3if getpointpiece(_mapchess, pos, i, -2) == flag1 and \getpointpiece(_mapchess, pos, i, -1) == flag1 and \getpointpiece(_mapchess, pos, i, 1) == flag1 and \getpointpiece(_mapchess, pos, i, 2) == flag1:value += 30000# *111_ 活三1，活三可以形成活四的三if getpointpiece(_mapchess, pos, i, 1) == flag1 and \getpointpiece(_mapchess, pos, i, 2) == flag1 and \getpointpiece(_mapchess, pos, i, 3) == flag1 and \getpointpiece(_mapchess, pos, i, 4) == 0:value += 20000# *1_11_ 活三2if getpointpiece(_mapchess, pos, i, 1) == flag1 and \getpointpiece(_mapchess, pos, i, 2) == 0 and \getpointpiece(_mapchess, pos, i, 3) == flag1 and \getpointpiece(_mapchess, pos, i, 4) == flag1 and \getpointpiece(_mapchess, pos, i, 5) == 0:value += 20000# *1112 眠三1  眠三是只能形成冲四的三if getpointpiece(_mapchess, pos, i, 1) == flag1 and \getpointpiece(_mapchess, pos, i, 2) == flag1 and \getpointpiece(_mapchess, pos, i, 3) == flag1 and \getpointpiece(_mapchess, pos, i, 4) == flag2:value += 15000# _1_112 眠三2if getpointpiece(_mapchess, pos, i, 1) == flag1 and \getpointpiece(_mapchess, pos, i, 2) == 0 and \getpointpiece(_mapchess, pos, i, 3) == flag1 and \getpointpiece(_mapchess, pos, i, 4) == flag1 and \getpointpiece(_mapchess, pos, i, 5) == flag2:value += 15000# _11_12 眠三3if getpointpiece(_mapchess, pos, i, 1) == flag1 and \getpointpiece(_mapchess, pos, i, 2) == flag1 and \getpointpiece(_mapchess, pos, i, 3) == 0 and \getpointpiece(_mapchess, pos, i, 4) == flag1 and \getpointpiece(_mapchess, pos, i, 5) == flag2:value += 15000# 1__11 眠三4if getpointpiece(_mapchess, pos, i, -1) == flag1 and \getpointpiece(_mapchess, pos, i, 1) == 0 and \getpointpiece(_mapchess, pos, i, 2) == flag1 and \getpointpiece(_mapchess, pos, i, 3) == flag1:value += 15000# 1_1_1 眠三5if getpointpiece(_mapchess, pos, i, -1) == flag1 and \getpointpiece(_mapchess, pos, i, 1) == flag1 and \getpointpiece(_mapchess, pos, i, 2) == 0 and \getpointpiece(_mapchess, pos, i, 3) == flag1:value += 15000# 2_111_2 眠三6if getpointpiece(_mapchess, pos, i, -1) == flag2 and \getpointpiece(_mapchess, pos, i, 1) == flag1 and \getpointpiece(_mapchess, pos, i, 2) == flag1 and \getpointpiece(_mapchess, pos, i, 3) == flag1 and \getpointpiece(_mapchess, pos, i, 4) == 0 and \getpointpiece(_mapchess, pos, i, 5) == flag2:value += 15000# __11__ 活二1  活二能够形成活三的二if getpointpiece(_mapchess, pos, i, -1) == 0 and \getpointpiece(_mapchess, pos, i, 1) == flag1 and \getpointpiece(_mapchess, pos, i, 2) == flag1 and \getpointpiece(_mapchess, pos, i, 3) == 0 and \getpointpiece(_mapchess, pos, i, 4) == 0:value += 10000# _1_1_ 活二2if getpointpiece(_mapchess, pos, i, 1) == flag1 and \getpointpiece(_mapchess, pos, i, 2) == 0 and \getpointpiece(_mapchess, pos, i, 3) == flag1 and \getpointpiece(_mapchess, pos, i, 4) == 0:value += 10000# 211__ 眠二1 ，能够形成眠三的二if getpointpiece(_mapchess, pos, i, -1) == flag2 and \getpointpiece(_mapchess, pos, i, 1) == flag1 and \getpointpiece(_mapchess, pos, i, 2) == flag1 and \getpointpiece(_mapchess, pos, i, 3) == 0 and \getpointpiece(_mapchess, pos, i, 4) == 0 and \getpointpiece(_mapchess, pos, i, 5) == 0:value += 1000#21_1__ 眠二2if getpointpiece(_mapchess, pos, i, -1) == flag2 and \getpointpiece(_mapchess, pos, i, 1) == flag1 and \getpointpiece(_mapchess, pos, i, 2) == 0 and \getpointpiece(_mapchess, pos, i, 3) == flag1 and \getpointpiece(_mapchess, pos, i, 4) == 0 and \getpointpiece(_mapchess, pos, i, 5) == 0:value += 1000#21__1_ 眠二3if getpointpiece(_mapchess, pos, i, -1) == flag2 and \getpointpiece(_mapchess, pos, i, 1) == flag1 and \getpointpiece(_mapchess, pos, i, 2) == 0 and \getpointpiece(_mapchess, pos, i, 3) == 0 and \getpointpiece(_mapchess, pos, i, 4) == flag1 and \getpointpiece(_mapchess, pos, i, 5) == 0:value += 1000#*1___1 眠二4if getpointpiece(_mapchess, pos, i, 1) == flag1 and \getpointpiece(_mapchess, pos, i, 2) == 0 and \getpointpiece(_mapchess, pos, i, 3) == 0 and \getpointpiece(_mapchess, pos, i, 4) == 0 and \getpointpiece(_mapchess, pos, i, 5) == flag1:value += 1000# *1__if getpointpiece(_mapchess, pos, i, 1) == flag1 and \getpointpiece(_mapchess, pos, i, 2) == 0 and \getpointpiece(_mapchess, pos, i, 3) == 0:value += 30# *1_if getpointpiece(_mapchess, pos, i, 1) == flag1 and \getpointpiece(_mapchess, pos, i, 2) == 0:value += 20# *1if getpointpiece(_mapchess, pos, i, 1) == flag1:value += 10return value# 获取当前坐标的各个方向上棋子属性，返回1代表白棋，返回2代表黑棋，返回0代表没有棋，返回5表示在棋盘外
def getpointpiece(_mapchess,pos, src, offset):# 8个方向directions = [[0, 1], [1, 1], [1, 0], [1, -1], [0, -1], [-1, -1], [-1, 0], [-1, 1]]x1, y1 = posx1 = x1 + directions[src - 1][0] * offset * blocksizey1 = y1 + directions[src - 1][1] * offset * blocksizeif x1 > 588 or y1 > 588 or x1 < 28 or y1 < 28:return 5else:return _mapchess[str(x1) + ',' + str(y1)]

这样就可以实现：当人下了棋后，电脑通过这个算法找出最有利的落子点，然后就在那里下棋。

注：本程序只是提供一个思路而已，并不是最优解。代码中value值可以自行修改，算法可以自己再设计，例如可以假如双活三之类的必须防御的应手。

如何判断胜负呢？待续。。。

python+pygame实现五子棋人机对战之四