自己动手实现俄罗斯方块

曾经终败给现在 2023-01-08 03:29 191阅读 0赞

### 俄罗斯方块 ###

记得很小的时候，从邻居家的小朋友那里拿到一个游戏机(按现在的眼光已经算不上游戏机了)，开始了人生中第一个电子游戏-俄罗斯方块，我不知道多少人是从那古老的游戏机而知道俄罗斯方块的，但俄罗斯方块的大名想必都听说过。

一个小小的俄罗斯方块就就能为我们增加无限的乐趣。当然了，如果能自己开发出来，岂不是很有成就感。

### UI ###

最近在写Frida可视化相关的项目。在选择UI框架的时候使用了PythonQt5。本文通过编写俄罗斯方块来熟悉PythonQt5的基本操作。

为什么选择PythonQt5?

1.  跨平台。这一点是C\#、MFC所不具备的。笔者用MFC写过游戏改键程序，有兴趣可以下载相应的代码: https://download.csdn.net/download/helloworlddm/11712844
2.  简单。Qt是基于C++的，学过C++的想必都被那一眼望不到边的语法规则给折磨过，而python语言相比C++就简单多了，没有让人迷糊的指针、引用、模板。

### 手写俄罗斯方块 ###

#### 方块形状 ####

俄罗斯方块称为积木拼图游戏。在这个游戏中,有七种不同形状叫方块: 如下图所示。这些形状的形成有四个方格。俄罗斯方块游戏的对象是移动和旋转的形状使他们适合尽可能多。如果我们设法形成一个行,该行摧毁我们得分。

![在这里插入图片描述][20210119000721493.png_pic_center]

#### 游戏思想 ####

我们使用QtCore.QBasicTimer()来创建一个游戏循环。  
俄罗斯方块是绘制的。  
图形是一个方块一个方块移动的（不是像素）  
图形其实是一个简单的数字列表。

#### 简化版 ####

游戏简化一点,让它更容易理解。在比赛开始后立即启动。我们可以通过按**p**键暂停游戏。空格键将立即把俄罗斯方块块放到底部。游戏是在恒定速度,实现没有加速度。分数是我们已经删除的行数。

#### 代码主体 ####

代码包括四类: Tetris, Board, Tetrominoe 和Shape。Tetris 类用来存放游戏。Board是编写游戏逻辑的地方。Tetrominoe类包含所有俄罗斯方块的名称，Shape类包含一个俄罗斯方块的代码。

##### main函数 #####

if __name__ == '__main__':
        app = QApplication([])
        tetris = Tetris()
        sys.exit(app.exec_())

##### Tetris类 #####

class Tetris(QMainWindow):
        
        def __init__(self):
            super().__init__()
            
            self.initUI()
            
            
        def initUI(self):    
            '''initiates application UI'''
    
            self.tboard = Board(self)
            # 居中
            self.setCentralWidget(self.tboard)
            #创建一个状态栏将显示消息。我们将显示三种可能的消息:已删除的行数,停顿了一下消息,或游戏结束的消息
            self.statusbar = self.statusBar()        
            self.tboard.msg2Statusbar[str].connect(self.statusbar.showMessage)
            # 启动游戏
            self.tboard.start()
            
            self.resize(180, 380)
            self.center()
            self.setWindowTitle('Tetris')        
            self.show()
            
    
        def center(self):
            '''centers the window on the screen'''
            # 窗口居中
            screen = QDesktopWidget().screenGeometry()
            size = self.geometry()
            self.move((screen.width()-size.width())/2, 
                (screen.height()-size.height())/2)

> QMainWindow: 主窗口为构建应用程序的用户界面提供了一个框架。  
> A main window provides a framework for building an application’s user  
> interface. Qt has QMainWindow and its related classes for main window  
> management. QMainWindow has its own layout to which you can add  
> QToolBars, QDockWidgets, a QMenuBar, and a QStatusBar. The layout has  
> a center area that can be occupied by any kind of widget. You can see  
> an image of the layout below.  
> ![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2hlbGxvd29ybGRkbQ_size_16_color_FFFFFF_t_70_pic_center]  
> void QMainWindow::setCentralWidget(QWidget \*widget)  
> **Sets the given widget to be the main window’s central widget.**  
> Note: QMainWindow takes ownership of the widget pointer and deletes it at the appropriate time.

这里涉及到信号机制。在后面会专门讲解。

self.tboard.msg2Statusbar[str].connect(self.statusbar.showMessage)

class Board(QFrame):
        # 创建一个signal
        msg2Statusbar = pyqtSignal(str)
    
        BoardWidth = 10
        BoardHeight = 22
        Speed = 300
    
        def __init__(self, parent):
            super().__init__(parent)
    
            self.initBoard()
    
        def initBoard(self):
    
            self.timer = QBasicTimer()
            self.isWaitingAfterLine = False
    
            self.curX = 0
            self.curY = 0
            self.numLinesRemoved = 0
            self.board = []
    
            self.setFocusPolicy(Qt.StrongFocus)
            self.isStarted = False
            self.isPaused = False
            self.clearBoard()
    
        def shapeAt(self, x, y):
            return self.board[(y * Board.BoardWidth) + x]
    
        def setShapeAt(self, x, y, shape):
            self.board[(y * Board.BoardWidth) + x] = shape
    
        def squareWidth(self):
            return self.contentsRect().width() // Board.BoardWidth
    
        def squareHeight(self):
            return self.contentsRect().height() // Board.BoardHeight
    
        def start(self):
    
            if self.isPaused:
                return
    
            self.isStarted = True
            self.isWaitingAfterLine = False
            self.numLinesRemoved = 0
            self.clearBoard()
    
            self.msg2Statusbar.emit(str(self.numLinesRemoved))
    
            self.newPiece()
            self.timer.start(Board.Speed, self)
    
        def pause(self):
    
            if not self.isStarted:
                return
    
            self.isPaused = not self.isPaused
    
            if self.isPaused:
                self.timer.stop()
                self.msg2Statusbar.emit("paused")
    
            else:
                self.timer.start(Board.Speed, self)
                self.msg2Statusbar.emit(str(self.numLinesRemoved))
    
            self.update()
    
        def paintEvent(self, event):
    
            painter = QPainter(self)
            rect = self.contentsRect()
    
            boardTop = rect.bottom() - Board.BoardHeight * self.squareHeight()
    
            for i in range(Board.BoardHeight):
                for j in range(Board.BoardWidth):
                    shape = self.shapeAt(j, Board.BoardHeight - i - 1)
    
                    if shape != Tetrominoe.NoShape:
                        self.drawSquare(painter,
                                        rect.left() + j * self.squareWidth(),
                                        boardTop + i * self.squareHeight(), shape)
    
            if self.curPiece.shape() != Tetrominoe.NoShape:
    
                for i in range(4):
                    x = self.curX + self.curPiece.x(i)
                    y = self.curY - self.curPiece.y(i)
                    self.drawSquare(painter, rect.left() + x * self.squareWidth(),
                                    boardTop + (Board.BoardHeight - y - 1) * self.squareHeight(),
                                    self.curPiece.shape())
    
        def keyPressEvent(self, event):
    
            if not self.isStarted or self.curPiece.shape() == Tetrominoe.NoShape:
                super(Board, self).keyPressEvent(event)
                return
    
            key = event.key()
    
            if key == Qt.Key_P:
                self.pause()
                return
    
            if self.isPaused:
                return
    
            elif key == Qt.Key_Left:
                self.tryMove(self.curPiece, self.curX - 1, self.curY)
    
            elif key == Qt.Key_Right:
                self.tryMove(self.curPiece, self.curX + 1, self.curY)
    
            elif key == Qt.Key_Down:
                self.tryMove(self.curPiece.rotateRight(), self.curX, self.curY)
    
            elif key == Qt.Key_Up:
                self.tryMove(self.curPiece.rotateLeft(), self.curX, self.curY)
    
            elif key == Qt.Key_Space:
                self.dropDown()
    
            elif key == Qt.Key_D:
                self.oneLineDown()
    
            else:
                super(Board, self).keyPressEvent(event)
    
        def timerEvent(self, event):
    
            if event.timerId() == self.timer.timerId():
    
                if self.isWaitingAfterLine:
                    self.isWaitingAfterLine = False
                    self.newPiece()
                else:
                    self.oneLineDown()
    
            else:
                super(Board, self).timerEvent(event)
    
        def clearBoard(self):
    
            for i in range(Board.BoardHeight * Board.BoardWidth):
                self.board.append(Tetrominoe.NoShape)
    
        def dropDown(self):
    
            newY = self.curY
    
            while newY > 0:
    
                if not self.tryMove(self.curPiece, self.curX, newY - 1):
                    break
    
                newY -= 1
    
            self.pieceDropped()
    
        def oneLineDown(self):
    
            if not self.tryMove(self.curPiece, self.curX, self.curY - 1):
                self.pieceDropped()
    
        def pieceDropped(self):
    
            for i in range(4):
                x = self.curX + self.curPiece.x(i)
                y = self.curY - self.curPiece.y(i)
                self.setShapeAt(x, y, self.curPiece.shape())
    
            self.removeFullLines()
    
            if not self.isWaitingAfterLine:
                self.newPiece()
    
        def removeFullLines(self):
    
            numFullLines = 0
            rowsToRemove = []
    
            for i in range(Board.BoardHeight):
    
                n = 0
                for j in range(Board.BoardWidth):
                    if not self.shapeAt(j, i) == Tetrominoe.NoShape:
                        n = n + 1
    
                if n == 10:
                    rowsToRemove.append(i)
    
            rowsToRemove.reverse()
    
            for m in rowsToRemove:
    
                for k in range(m, Board.BoardHeight):
                    for l in range(Board.BoardWidth):
                        self.setShapeAt(l, k, self.shapeAt(l, k + 1))
    
            numFullLines = numFullLines + len(rowsToRemove)
    
            if numFullLines > 0:
                self.numLinesRemoved = self.numLinesRemoved + numFullLines
                self.msg2Statusbar.emit(str(self.numLinesRemoved))
    
                self.isWaitingAfterLine = True
                self.curPiece.setShape(Tetrominoe.NoShape)
                self.update()
    
        def newPiece(self):
    
            self.curPiece = Shape()
            self.curPiece.setRandomShape()
            self.curX = Board.BoardWidth // 2 + 1
            self.curY = Board.BoardHeight - 1 + self.curPiece.minY()
    
            if not self.tryMove(self.curPiece, self.curX, self.curY):
                self.curPiece.setShape(Tetrominoe.NoShape)
                self.timer.stop()
                self.isStarted = False
                self.msg2Statusbar.emit("Game over")
    
        def tryMove(self, newPiece, newX, newY):
    
            for i in range(4):
    
                x = newX + newPiece.x(i)
                y = newY - newPiece.y(i)
    
                if x < 0 or x >= Board.BoardWidth or y < 0 or y >= Board.BoardHeight:
                    return False
    
                if self.shapeAt(x, y) != Tetrominoe.NoShape:
                    return False
    
            self.curPiece = newPiece
            self.curX = newX
            self.curY = newY
            self.update()
    
            return True
    
        def drawSquare(self, painter, x, y, shape):
    
            colorTable = [0x000000, 0xCC6666, 0x66CC66, 0x6666CC,
                          0xCCCC66, 0xCC66CC, 0x66CCCC, 0xDAAA00]
    
            color = QColor(colorTable[shape])
            painter.fillRect(x + 1, y + 1, self.squareWidth() - 2,
                             self.squareHeight() - 2, color)
    
            painter.setPen(color.lighter())
            painter.drawLine(x, y + self.squareHeight() - 1, x, y)
            painter.drawLine(x, y, x + self.squareWidth() - 1, y)
    
            painter.setPen(color.darker())
            painter.drawLine(x + 1, y + self.squareHeight() - 1,
                             x + self.squareWidth() - 1, y + self.squareHeight() - 1)
            painter.drawLine(x + self.squareWidth() - 1,
                             y + self.squareHeight() - 1, x + self.squareWidth() - 1, y + 1)

> QBasicTimer: 为对象提供timer(计时器)事件。  
> This is a fast, lightweight, and low-level class used by Qt internally. We recommend using the higher-level QTimer class rather than this class if you want to use timers in your applications. **Note that this timer is a repeating timer that will send subsequent timer events unless the stop() function is called.**  
> void QBasicTimer::start(int msec, QObject \*object)  
> Starts (or restarts) the timer with a msec milliseconds timeout. The timer will be a Qt::CoarseTimer. See Qt::TimerType for information on the different timer types.

##### Tetrominoe(7种形状) #####

class Tetrominoe(object):
        NoShape = 0
        ZShape = 1
        SShape = 2
        LineShape = 3
        TShape = 4
        SquareShape = 5
        LShape = 6
        MirroredLShape = 7

#####  #####

class Shape(object):
        
        coordsTable = (
            ((0, 0),     (0, 0),     (0, 0),     (0, 0)),
            ((0, -1),    (0, 0),     (-1, 0),    (-1, 1)),
            ((0, -1),    (0, 0),     (1, 0),     (1, 1)),
            ((0, -1),    (0, 0),     (0, 1),     (0, 2)),
            ((-1, 0),    (0, 0),     (1, 0),     (0, 1)),
            ((0, 0),     (1, 0),     (0, 1),     (1, 1)),
            ((-1, -1),   (0, -1),    (0, 0),     (0, 1)),
            ((1, -1),    (0, -1),    (0, 0),     (0, 1))
        )
    
        def __init__(self):
            
            self.coords = [[0,0] for i in range(4)]
            self.pieceShape = Tetrominoe.NoShape
    
            self.setShape(Tetrominoe.NoShape)
            
    
        def shape(self):
            
            return self.pieceShape
            
    
        def setShape(self, shape):
            '''sets a shape'''
            
            table = Shape.coordsTable[shape]
            
            for i in range(4):
                for j in range(2):
                    self.coords[i][j] = table[i][j]
    
            self.pieceShape = shape
            
    
        def setRandomShape(self):
            '''chooses a random shape'''
            
            self.setShape(random.randint(1, 7))
    
            
        def x(self, index):
            '''returns x coordinate'''
            
            return self.coords[index][0]
    
            
        def y(self, index):
            '''returns y coordinate'''
            
            return self.coords[index][1]
    
            
        def setX(self, index, x):
            '''sets x coordinate'''
            
            self.coords[index][0] = x
    
            
        def setY(self, index, y):
            '''sets y coordinate'''
            
            self.coords[index][1] = y
    
            
        def minX(self):
            '''returns min x value'''
            
            m = self.coords[0][0]
            for i in range(4):
                m = min(m, self.coords[i][0])
    
            return m
    
            
        def maxX(self):
            '''returns max x value'''
            
            m = self.coords[0][0]
            for i in range(4):
                m = max(m, self.coords[i][0])
    
            return m
    
            
        def minY(self):
            '''returns min y value'''
            
            m = self.coords[0][1]
            for i in range(4):
                m = min(m, self.coords[i][1])
    
            return m
    
            
        def maxY(self):
            '''returns max y value'''
            
            m = self.coords[0][1]
            for i in range(4):
                m = max(m, self.coords[i][1])
    
            return m
    
            
        def rotateLeft(self):
            '''rotates shape to the left'''
            
            if self.pieceShape == Tetrominoe.SquareShape:
                return self
    
            result = Shape()
            result.pieceShape = self.pieceShape
            
            for i in range(4):
                
                result.setX(i, self.y(i))
                result.setY(i, -self.x(i))
    
            return result
    
            
        def rotateRight(self):
            '''rotates shape to the right'''
            
            if self.pieceShape == Tetrominoe.SquareShape:
                return self
    
            result = Shape()
            result.pieceShape = self.pieceShape
            
            for i in range(4):
                
                result.setX(i, -self.y(i))
                result.setY(i, self.x(i))
    
            return result

俄罗斯方块的坐标系:  
![在这里插入图片描述][20210119225513696.png_pic_center]

### 写在最后 ###

界面编程是一件很有成就感的事情。快过年了，可以用这个俄罗斯方块来炫以下技能。

### 公众号 ###

更多内容，欢迎关注我的微信公众号:无情剑客  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2hlbGxvd29ybGRkbQ_size_16_color_FFFFFF_t_70_pic_center 1]

[20210119000721493.png_pic_center]: /images/20221119/ad972ff8ddb4486ebcff1efa93144904.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2hlbGxvd29ybGRkbQ_size_16_color_FFFFFF_t_70_pic_center]: /images/20221119/3aa6210d8b864629b475514bddf7ad04.png
[20210119225513696.png_pic_center]: /images/20221119/24eefaec48164814935eadb45653f54a.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2hlbGxvd29ybGRkbQ_size_16_color_FFFFFF_t_70_pic_center 1]: /images/20221119/93bd06fc2f8547d2bde6727e6e48e21e.png