add code

Author: itdoudoutech

doudou/2020-06-12-maze/maze.py

@@ -0,0 +1,221 @@
+import random
+import pyxel
+
+
+# Python 3.6.9+
+#
+# Win:
+# pip install -U pyxel
+# ************************
+# Mac
+# 1、brew install python3 sdl2 sdl2_image
+# 2、restart the terminal
+# 3、pip3 install -U pyxel
+# ************************
+# 「S」键开启游戏
+# https://github.com/kitao/pyxel/blob/master/README.cn.md
+
+class Maze:
+    def __init__(self, width, height):
+        self.width = width
+        self.height = height
+        self.map = [[0 if x % 2 == 1 and y % 2 == 1 else 1 for x in range(width)] for y in range(height)]
+        self.map[1][0] = 0  # 入口
+        self.map[height - 2][width - 1] = 0  # 出口
+        self.visited = []
+        # right up left down
+        self.dx = [1, 0, -1, 0]
+        self.dy = [0, -1, 0, 1]
+
+    def set_value(self, point, value):
+        self.map[point[1]][point[0]] = value
+
+    def get_value(self, point):
+        return self.map[point[1]][point[0]]
+
+    # 获取坐标（x,y） 的邻居 返回数据结构为：二维数组
+    def get_neighbor(self, x, y, value):
+        res = []
+        for i in range(4):
+            if 0 < x + self.dx[i] < self.width - 1 and 0 < y + self.dy[i] < self.height - 1 and \
+                    self.get_value([x + self.dx[i], y + self.dy[i]]) == value:
+                res.append([x + self.dx[i], y + self.dy[i]])
+        return res
+
+    # 获取坐标（x,y） 的邻墙
+    def get_neighbor_wall(self, point):
+        return self.get_neighbor(point[0], point[1], 1)
+
+    # 获取坐标（x,y） 的邻路
+    def get_neighbor_road(self, point):
+        return self.get_neighbor(point[0], point[1], 0)
+
+    def deal_with_not_visited(self, point, wall_position, wall_list):
+        if not [point[0], point[1]] in self.visited:
+            self.set_value(wall_position, 0)
+            self.visited.append(point)
+            wall_list += self.get_neighbor_wall(point)
+
+    # generate maze
+    # https://en.wikipedia.org/wiki/Maze_generation_algorithm
+    #
+    # 1、迷宫行和列必须为奇数。
+    # 2、奇数行和奇数列的交叉点为路，其余点为墙。迷宫四周全是墙。
+    # 3、选定一个为路的单元格（本例选 [1,1]），然后把它的邻墙放入列表 wall。
+    # 4、当列表 wall 里还有墙时：
+    #     4.1、从列表里随机选一面墙，如果这面墙分隔的两个单元格只有一个单元格被访问过
+    #         3.1.1、那就从列表里移除这面墙，同时把墙打通
+    #         3.1.2、将单元格标记为已访问
+    #         3.1.3、将未访问的单元格的的邻墙加入列表 wall
+    #     4.2、如果这面墙两面的单元格都已经被访问过，那就从列表里移除这面墙
+    def generate(self):
+        start = [1, 1]
+        self.visited.append(start)
+        wall_list = self.get_neighbor_wall(start)
+        while wall_list:
+            wall_position = random.choice(wall_list)
+            neighbor_road = self.get_neighbor_road(wall_position)
+            wall_list.remove(wall_position)
+            self.deal_with_not_visited(neighbor_road[0], wall_position, wall_list)
+            self.deal_with_not_visited(neighbor_road[1], wall_position, wall_list)
+
+    def is_out_of_index(self, x, y):
+        return x == 0 or x == self.width - 1 or y == 0 or y == self.height - 1
+
+    # dfs
+    def dfs(self, x, y, path, visited=[]):
+        # 越界
+        if self.is_out_of_index(x, y):
+            return False
+
+        # 访问过 or 撞墙
+        if [x, y] in visited or self.get_value([x, y]) == 1:
+            return False
+
+        visited.append([x, y])
+        path.append([x, y])
+
+        # over
+        if x == self.width - 2 and y == self.height - 2:
+            return True
+
+        # recursive
+        for i in range(4):
+            if 0 < x + self.dx[i] < self.width - 1 and 0 < y + self.dy[i] < self.height - 1 and \
+                    self.get_value([x + self.dx[i], y + self.dy[i]]) == 0:
+                if self.dfs(x + self.dx[i], y + self.dy[i], path, visited):
+                    return True
+                elif not self.is_out_of_index(x, y) and path[-1] != [x, y]:
+                    path.append([x, y])
+
+    # dfs
+    def dfs_route(self):
+        path = []
+        self.dfs(1, 1, path)
+
+        ans = [[0, 1]]
+        for i in range(len(path)):
+            ans.append(path[i])
+            if 0 < i < len(path) - 1 and path[i - 1] == path[i + 1]:
+                ans.append(path[i])
+        ans.append([width - 1, height - 2])
+        return ans
+
+    # bfs
+    def bfs_route(self):
+        start = {'x': 0, 'y': 1, 'prev': None}
+        now = start
+        q = [start]
+        visited = [[start['x'], start['y']]]
+        # 1、从起点出发，获取起点周围所有连通的路
+        # 2、如果该路没有走过，则加入队列 Q，否则跳过 同时记录其前驱节点
+        while q:
+            now = q.pop(0)
+            # 结束
+            if now['x'] == self.width - 2 and now['y'] == self.height - 2:
+                break
+            roads = my_maze.get_neighbor_road([now['x'], now['y']])
+            for road in roads:
+                if not road in visited:
+                    visited.append(road)
+                    q.append({'x': road[0], 'y': road[1], 'prev': now})
+
+        ans = []
+        while now:
+            ans.insert(0, [now['x'], now['y']])
+            now = now['prev']
+        ans.append([width - 1, height - 2])
+        return ans
+
+
+pixel = 5
+width, height = 37, 21
+road_color, wall_color = 7, 13
+start_point_color, end_point_color, = 11, 11
+head_color, route_color, backtrack_color = 9, 11, 8
+
+my_maze = Maze(width, height)
+my_maze.generate()
+
+
+class App:
+    def __init__(self):
+        #pyxel.init(width * pixel, height * pixel, caption='maze', border_width=10, border_color=0xFFFFFF)
+        pyxel.init(width * pixel, height * pixel)
+        self.death = True
+        self.index = 0
+        self.route = []
+        self.step = 1  # 步长，数值越小速度越快，1：每次一格； 10：每次 1/10 格
+        self.color = start_point_color
+        self.bfs_route = my_maze.bfs_route()
+        self.dfs_route = my_maze.dfs_route()
+        self.dfs_model = True
+        pyxel.run(self.update, self.draw)
+
+    def update(self):
+        if pyxel.btn(pyxel.KEY_Q):
+            pyxel.quit()
+
+        if pyxel.btn(pyxel.KEY_S):
+            self.death = False
+
+        if not self.death:
+            self.check_death()
+            self.update_route()
+
+    def draw(self):
+        # draw maze
+        for x in range(height):
+            for y in range(width):
+                color = road_color if my_maze.map[x][y] is 0 else wall_color
+                pyxel.rect(y * pixel, x * pixel, pixel, pixel, color)
+        pyxel.rect(0, pixel, pixel, pixel, start_point_color)
+        pyxel.rect((width - 1) * pixel, (height - 2) * pixel, pixel, pixel, end_point_color)
+
+        if self.index > 0:
+            # draw route
+            offset = pixel / 2
+            for i in range(len(self.route) - 1):
+                curr = self.route[i]
+                next = self.route[i + 1]
+                self.color = backtrack_color if curr in self.route[:i] and next in self.route[:i] else route_color
+                pyxel.line(curr[0] + offset, (curr[1] + offset), next[0] + offset, next[1] + offset, self.color)
+            pyxel.circ(self.route[-1][0] + 2, self.route[-1][1] + 2, 1, head_color)
+
+    def check_death(self):
+        if self.dfs_model and len(self.route) == len(self.dfs_route) - 1:
+            self.death = True
+        elif not self.dfs_model and len(self.route) == len(self.bfs_route) - 1:
+            self.death = True
+
+    def update_route(self):
+        index = int(self.index / self.step)
+        self.index += 1
+        if index == len(self.route):  # move
+            if self.dfs_model:
+                self.route.append([pixel * self.dfs_route[index][0], pixel * self.dfs_route[index][1]])
+            else:
+                self.route.append([pixel * self.bfs_route[index][0], pixel * self.bfs_route[index][1]])
+
+
+App()

doudou/README.md

@@ -17,10 +17,12 @@ Python技术 公众号文章代码库
 + [520](https://github.com/JustDoPython/python-examples/tree/master/doudou/2020-05-17-520)：Python 教你花式表白小姐姐
 
 + [字符画](https://github.com/JustDoPython/python-examples/tree/master/doudou/2020-05-17-character-drawing)：字符画
+
++ [迷宫](https://github.com/JustDoPython/python-examples/tree/master/doudou/2020-06-12-maze)：迷宫
 ---
 
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+关注公众号：python 技术，回复「python」一起学习交流。
 
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