使用PyQt6构建一个snake game

from PyQt6.QtCore import Qt, QTimer
from PyQt6.QtGui import QColor, QPainter
from PyQt6.QtWidgets import QApplication, QMainWindow

CELL_SIZE = 30
GRID_SIZE = 20
SNAKE_INITIAL_LENGTH = 3
SNAKE_INITIAL_POSITION = (GRID_SIZE // 2, GRID_SIZE // 2)
SNAKE_INITIAL_DIRECTION = Qt.Key.Key_Right
FOOD_COLOR = QColor(0, 255, 0)  ## Green color

class SnakeGame(QMainWindow):
    def __init__(self):
        super().__init__()
        self.setWindowTitle("Snake Game")
        self.setFixedSize(CELL_SIZE * GRID_SIZE, CELL_SIZE * GRID_SIZE)
        
        self.snake = [(SNAKE_INITIAL_POSITION[0], SNAKE_INITIAL_POSITION[1] + i) for i in range(SNAKE_INITIAL_LENGTH)]
        self.direction = SNAKE_INITIAL_DIRECTION
        self.food = self.generate_food()

        self.timer = QTimer()
        self.timer.timeout.connect(self.move_snake)
        self.timer.start(200)  ## Snake movement speed
        
    def paintEvent(self, event):
        painter = QPainter(self)
        painter.setRenderHint(QPainter.RenderHint.Antialiasing)
        
        ## Draw snake
        for x, y in self.snake:
            painter.fillRect(x * CELL_SIZE, y * CELL_SIZE, CELL_SIZE, CELL_SIZE, Qt.GlobalColor.black)
        
        ## Draw food
        painter.fillRect(self.food[0] * CELL_SIZE, self.food[1] * CELL_SIZE, CELL_SIZE, CELL_SIZE, FOOD_COLOR)
    
    def keyPressEvent(self, event):
        if event.key() == Qt.Key.Key_Up:
            if self.direction != Qt.Key.Key_Down:
                self.direction = Qt.Key.Key_Up
        elif event.key() == Qt.Key.Key_Down:
            if self.direction != Qt.Key.Key_Up:
                self.direction = Qt.Key.Key_Down
        elif event.key() == Qt.Key.Key_Left:
            if self.direction != Qt.Key.Key_Right:
                self.direction = Qt.Key.Key_Left
        elif event.key() == Qt.Key.Key_Right:
            if self.direction != Qt.Key.Key_Left:
                self.direction = Qt.Key.Key_Right

    
    def move_snake(self):
        x, y = self.snake[0]
        
        if self.direction == Qt.Key.Key_Up:
            y -= 1
        elif self.direction == Qt.Key.Key_Down:
            y += 1
        elif self.direction == Qt.Key.Key_Left:
            x -= 1
        elif self.direction == Qt.Key.Key_Right:
            x += 1
        
        if not self.is_valid_move(x, y):
            self.timer.stop()
            return
        
        self.snake.insert(0, (x, y))
        
        if (x, y) == self.food:
            self.food = self.generate_food()
        else:
            self.snake.pop()
        
        self.update()
    
    def is_valid_move(self, x, y):
        if x < 0 or x >= GRID_SIZE or y < 0 or y >= GRID_SIZE:
            return False
        
        if (x, y) in self.snake[1:]:
            return False
        
        return True
    
    def generate_food(self):
        import random
        while True:
            x = random.randint(0, GRID_SIZE - 1)
            y = random.randint(0, GRID_SIZE - 1)
            if (x, y) not in self.snake:
                return x, y

if __name__ == '__main__':
    app = QApplication([])
    game = SnakeGame()
    game.show()
    app.exec()

代码注释

这是一个使用PyQt6库实现的贪吃蛇游戏的程序。下面是对程序的解释和注释：

from PyQt6.QtCore import Qt, QTimer
from PyQt6.QtGui import QColor, QPainter
from PyQt6.QtWidgets import QApplication, QMainWindow

导入了PyQt6库的核心模块Qt、定时器模块QTimer，图形模块QColor和QPainter，以及窗口模块QApplication和QMainWindow。

CELL_SIZE = 30
GRID_SIZE = 20
SNAKE_INITIAL_LENGTH = 3
SNAKE_INITIAL_POSITION = (GRID_SIZE // 2, GRID_SIZE // 2)
SNAKE_INITIAL_DIRECTION = Qt.Key.Key_Right
FOOD_COLOR = QColor(0, 255, 0)  ## 绿色
定义了一些常量，包括单元格大小CELL_SIZE，网格大小GRID_SIZE，蛇的初始长度SNAKE_INITIAL_LENGTH，蛇的初始位置SNAKE_INITIAL_POSITION，蛇的初始移动方向SNAKE_INITIAL_DIRECTION，以及食物的颜色FOOD_COLOR。

class SnakeGame(QMainWindow):
    def __init__(self):
        super().__init__()
        self.setWindowTitle("Snake Game")
        self.setFixedSize(CELL_SIZE * GRID_SIZE, CELL_SIZE * GRID_SIZE)
        
        self.snake = [(SNAKE_INITIAL_POSITION[0], SNAKE_INITIAL_POSITION[1] + i) for i in range(SNAKE_INITIAL_LENGTH)]
        self.direction = SNAKE_INITIAL_DIRECTION
        self.food = self.generate_food()

        self.timer = QTimer()
        self.timer.timeout.connect(self.move_snake)
        self.timer.start(200)  ## 蛇的移动速度
        
    def paintEvent(self, event):
        painter = QPainter(self)
        painter.setRenderHint(QPainter.RenderHint.Antialiasing)
        
        ##绘制蛇
        for x, y in self.snake:
            painter.fillRect(x * CELL_SIZE, y * CELL_SIZE, CELL_SIZE, CELL_SIZE, Qt.GlobalColor.black)
        
        ## 绘制食物
        painter.fillRect(self.food[0] * CELL_SIZE, self.food[1] * CELL_SIZE, CELL_SIZE, CELL_SIZE, FOOD_COLOR)

SnakeGame是一个继承自QMainWindow的类，表示整个游戏窗口。在初始化方法__init__中，设置了窗口标题和固定的窗口大小。初始化了蛇的初始位置、移动方向和食物，并创建了一个QTimer定时器，设置定时器的超时信号连接到move_snake方法上，并开始定时器。在paintEvent方法中，使用QPainter对象进行绘制，首先绘制蛇，然后绘制食物。

def keyPressEvent(self, event):
        if event.key() == Qt.Key.Key_Up:
            if self.direction != Qt.Key.Key_Down:
                self.direction = Qt.Key.Key_Up
        elif event.key() == Qt.Key.Key_Down:
            if self.direction != Qt.Key.Key_Up:
                self.direction = Qt.Key.Key_Down
        elif event.key() == Qt.Key.Key_Left:
            if self.direction != Qt.Key.Key_Right:
                self.direction = Qt.Key.Key_Left
        elif event.key() == Qt.Key.Key_Right:
            if self.direction != Qt.Key.Key_Left:
                self.direction = Qt.Key.Key_Right

在按键事件keyPressEvent中，根据按下的键盘按键修改蛇的移动方向。如果按下的是向上键并且当前方向不是向下，则将方向设为向上。类似地，如果按下的是向下、向左或向右键，并且当前方向不是相反方向，则更新蛇的移动方向。

def move_snake(self):
        x, y = self.snake[0]
        
        if self.direction == Qt.Key.Key_Up:
            y -= 1
        elif self.direction == Qt.Key.Key_Down:
            y += 1
        elif self.direction == Qt.Key.Key_Left:
            x -= 1
        elif self.direction == Qt.Key.Key_Right:
            x += 1
        
        if not self.is_valid_move(x, y):
            self.timer.stop()
            return
        
        self.snake.insert(0, (x, y))
        
        if (x, y) == self.food:
            self.food = self.generate_food()
        else:
            self.snake.pop()
        
        self.update()

move_snake方法用于更新蛇的位置。根据当前的移动方向，计算出蛇头的新坐标(x,
y)。然后检查新的坐标是否是有效的移动，如果无效，则停止定时器并返回。如果新坐标与食物的坐标相同，则表示蛇吃到了食物，将食物位置更新为新的随机位置，否则从蛇的尾部移除一个坐标。最后，调用update方法触发窗口的重绘。

def is_valid_move(self, x, y):
        if x < 0 or x >= GRID_SIZE or y < 0 or y >= GRID_SIZE:
            return False
        
        if (x, y) in self.snake[1:]:
            return False
        
        return True

is_valid_move方法用于检查给定的坐标是否是有效的蛇的移动。如果坐标超出了网格范围，或者坐标在蛇的身体中已经存在，则返回False，否则返回True。

def generate_food(self):
        import random
        while True:
            x = random.randint(0, GRID_SIZE - 1)
            y = random.randint(0, GRID_SIZE - 1)
            if (x, y) not in self.snake:
                return x, y

generate_food方法用于生成食物的随机位置。使用random模块生成一个随机的x和y坐标，并检查该坐标是否在蛇的身体中。如果不在，则返回该坐标作为食物的位置。

if __name__ == '__main__':
    app = QApplication([])
    game = SnakeGame()
    game.show()
    app.exec()

在主程序中，创建一个QApplication对象app和SnakeGame对象game，然后显示游戏窗口，并开始应用程序的事件循环，以使窗口能够接收和处理事件。

增加背景音乐，网格，计分

from PyQt6.QtCore import Qt, QTimer, QUrl
from PyQt6.QtGui import QColor, QPainter
from PyQt6.QtWidgets import QApplication, QMainWindow, QLabel
from PyQt6.QtMultimedia import QMediaPlayer, QAudio, QAudioOutput
from PyQt6.QtMultimedia import QSoundEffect


CELL_SIZE = 30
GRID_SIZE = 20
SNAKE_INITIAL_LENGTH = 3
SNAKE_INITIAL_POSITION = (GRID_SIZE // 2, GRID_SIZE // 2)
SNAKE_INITIAL_DIRECTION = Qt.Key.Key_Right
FOOD_COLOR = QColor(0, 255, 0)  ## Green color

class SnakeGame(QMainWindow):
    def __init__(self):
        super().__init__()
        self.setWindowTitle("Snake Game")
        self.setFixedSize(CELL_SIZE * GRID_SIZE, CELL_SIZE * GRID_SIZE)
        
        self.snake = [(SNAKE_INITIAL_POSITION[0], SNAKE_INITIAL_POSITION[1] + i) for i in range(SNAKE_INITIAL_LENGTH)]
        self.direction = SNAKE_INITIAL_DIRECTION
        self.food = self.generate_food()
        
        self.score = 0
        
        self.score_label = QLabel(self)
        self.score_label.setGeometry(10, 10, 100, 30)
        self.score_label.setText("Score: 0")

        self.timer = QTimer()
        self.timer.timeout.connect(self.move_snake)
        self.timer.start(200)  ## Snake movement speed

        
        

        

        self.filename = "bg_music.mp3"
        self.player = QMediaPlayer()
        self.audio_output = QAudioOutput()
        self.player.setAudioOutput(self.audio_output)
        self.player.setSource(QUrl.fromLocalFile(self.filename))
        self.audio_output.setVolume(50)
        
        ## 在音乐播放结束时重新开始播放
        self.player.mediaStatusChanged.connect(self.on_music_status_changed)
        
        ## 开始播放背景音乐
        self.player.play()
        
    def on_music_status_changed(self, status):
        if status == QMediaPlayer.MediaStatus.EndOfMedia:
            self.player.setPosition(0)  # 将音乐位置重置为0
            self.player.play()  # 重新播放背景音乐
    
    def paintEvent(self, event):
        painter = QPainter(self)
        painter.setRenderHint(QPainter.RenderHint.Antialiasing)
        
        ## 绘制网格
        painter.setPen(Qt.GlobalColor.blue)  # 设置线条颜色为蓝色
        for i in range(GRID_SIZE):
            painter.drawLine(0, i * CELL_SIZE, self.width(), i * CELL_SIZE)  ## 绘制水平线
            painter.drawLine(i * CELL_SIZE, 0, i * CELL_SIZE, self.height())  ## 绘制垂直线
        
        ## 绘制蛇
        for x, y in self.snake:
            painter.fillRect(x * CELL_SIZE, y * CELL_SIZE, CELL_SIZE, CELL_SIZE, Qt.GlobalColor.black)
        
        ## 绘制食物
        painter.fillRect(self.food[0] * CELL_SIZE, self.food[1] * CELL_SIZE, CELL_SIZE, CELL_SIZE, FOOD_COLOR)
    
    def keyPressEvent(self, event):
        if event.key() == Qt.Key.Key_Up:
            if self.direction != Qt.Key.Key_Down:
                self.direction = Qt.Key.Key_Up
        elif event.key() == Qt.Key.Key_Down:
            if self.direction != Qt.Key.Key_Up:
                self.direction = Qt.Key.Key_Down
        elif event.key() == Qt.Key.Key_Left:
            if self.direction != Qt.Key.Key_Right:
                self.direction = Qt.Key.Key_Left
        elif event.key() == Qt.Key.Key_Right:
            if self.direction != Qt.Key.Key_Left:
                self.direction = Qt.Key.Key_Right

    
    def move_snake(self):
        x, y = self.snake[0]
        
        if self.direction == Qt.Key.Key_Up:
            y -= 1
        elif self.direction == Qt.Key.Key_Down:
            y += 1
        elif self.direction == Qt.Key.Key_Left:
            x -= 1
        elif self.direction == Qt.Key.Key_Right:
            x += 1
        
        if not self.is_valid_move(x, y):
            self.timer.stop()
            return
        
        self.snake.insert(0, (x, y))
        
        if (x, y) == self.food:
            self.score += 1
            self.score_label.setText("Score: {}".format(self.score))
            self.food = self.generate_food()
        else:
            self.snake.pop()
        
        self.update()
    
    def is_valid_move(self, x, y):
        if x < 0 or x >= GRID_SIZE or y < 0 or y >= GRID_SIZE:
            return False
        
        if (x, y) in self.snake[1:]:
            return False
        
        return True
    
    def generate_food(self):
        import random
        while True:
            x = random.randint(0, GRID_SIZE - 1)
            y = random.randint(0, GRID_SIZE - 1)
            if (x, y) not in self.snake:
                return x, y

if __name__ == '__main__':
    app = QApplication([])
    app.setStyle("fusion")  # 使用Fusion样式，确保网格线条显示正常
    game = SnakeGame()
    game.show()
    app.exec()