Python : PyQt5を使えばテトリスが作れるらしい

環境
・Windows 10
・Python

blogはこちら
https://toypool.hatenablog.com/entry/2019/01/23/14094

## PyQt5とは

>PyQt5 is a module that can be used to create graphical user interfaces (GUI). PyQt5 is not backwards compatible with PyQt4.

>You will need Python 2.6+ or newer. To test your Python version try one of these commands:

https://pythonspot.com/pyqt5/

要するに、Pythonでいい感じのGUIをつくれるモジュールってことですね

## チュートリアル
かなり整理されているチュートリアルがあります
PyQt5 tutorial
http://zetcode.com/gui/pyqt5/

全部やりましたが、

「あ、exeでインストールした時のあれってこうやって作るのね！」

と感動することが多かったです。

## Tetris in PyQt5
テトリスまで作っていました。

![tet.png](https://qiita-image-store.s3.amazonaws.com/0/346819/50b19987-d022-7e13-3480-c607818b2c37.png)

ソースコードはこちら

20190128_追記:こちらに元コードと詳しい解説が載っています。
http://zetcode.com/gui/pyqt5/tetris/

```python:tetris.py
#!/usr/bin/python3
# -*- coding: utf-8 -*-

"""
ZetCode PyQt5 tutorial

This is a Tetris game clone.

Author: Jan Bodnar
Website: zetcode.com
Last edited: August 2017
"""

from PyQt5.QtWidgets import QMainWindow, QFrame, QDesktopWidget, QApplication
from PyQt5.QtCore import Qt, QBasicTimer, pyqtSignal
from PyQt5.QtGui import QPainter, QColor
import sys, random

class Tetris(QMainWindow):

    def __init__(self):
        super().__init__()

        self.initUI()


    def initUI(self):
        '''initiates application UI'''

        self.tboard = Board(self)
        self.setCentralWidget(self.tboard)

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

        self.tboard.start()

        self.resize(180, 380)
        self.center()
        self.setWindowTitle('Tetris')
        self.show()


    def center(self):
        '''centers the window on the screen'''

        screen = QDesktopWidget().screenGeometry()
        size = self.geometry()
        self.move((screen.width()-size.width())/2,
            (screen.height()-size.height())/2)


class Board(QFrame):

    msg2Statusbar = pyqtSignal(str)

    BoardWidth = 10
    BoardHeight = 22
    Speed = 300

    def __init__(self, parent):
        super().__init__(parent)

        self.initBoard()


    def initBoard(self):
        '''initiates board'''

        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):
        '''determines shape at the board position'''

        return self.board[(y * Board.BoardWidth) + x]


    def setShapeAt(self, x, y, shape):
        '''sets a shape at the board'''

        self.board[(y * Board.BoardWidth) + x] = shape


    def squareWidth(self):
        '''returns the width of one square'''

        return self.contentsRect().width() // Board.BoardWidth


    def squareHeight(self):
        '''returns the height of one square'''

        return self.contentsRect().height() // Board.BoardHeight


    def start(self):
        '''starts game'''

        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):
        '''pauses game'''

        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):
        '''paints all shapes of the game'''

        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):
        '''processes key press events'''

        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):
        '''handles timer 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):
        '''clears shapes from the board'''

        for i in range(Board.BoardHeight * Board.BoardWidth):
            self.board.append(Tetrominoe.NoShape)


    def dropDown(self):
        '''drops down a shape'''

        newY = self.curY

        while newY > 0:

            if not self.tryMove(self.curPiece, self.curX, newY - 1):
                break

            newY -= 1

        self.pieceDropped()


    def oneLineDown(self):
        '''goes one line down with a shape'''

        if not self.tryMove(self.curPiece, self.curX, self.curY - 1):
            self.pieceDropped()


    def pieceDropped(self):
        '''after dropping shape, remove full lines and create new shape'''

        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):
        '''removes all full lines from the board'''

        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):
        '''creates a new shape'''

        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):
        '''tries to move a shape'''

        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):
        '''draws a square of a 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)


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):
        '''returns shape'''

        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


if __name__ == '__main__':

    app = QApplication([])
    tetris = Tetris()
    sys.exit(app.exec_())

```

## 実行方法

```
python tetris.py
```
実行はとても簡単です。

## おわりに
最近は小さなアプリケーションを作ることが増えたので特にオフラインのアプリを作る際に重宝しそうです。