Pygame - 移动矩形中的中心文本

问题描述

我正在 pygame 中制作一个数字游戏，并且有一些方块会从屏幕顶部落到底部，同时有一个数值，并且该数字显示在每个方块上。我正在努力使文本以正方形为中心，当每个数字可以包含 1 - 4 位数字时，这会变得更加困难

class sqr:
    def __init__(self):
        self.colours = [(255,0),(0,255,255)]
        self.Xpositions = [0,125,245,365,485]
        self.OnScreen = False
        self.X = random.choice(self.Xpositions) 
        self.Y = 0
        self.colour = random.choice(self.colours)
        self.number = random.choice([20,40,80])
        self.numberFont =  pygame.font.Font("TitilliumWeb-Black.ttf",48)

    def drawSquare(self,colour,X,Y):
        pygame.draw.rect(screen,(X,Y,120,120))

    def numberTextFunc(self,Y):
        numberText = self.numberFont.render(f"{self.number}",True,(87,63,63))
        screen.blit(numberText,Y))

square = sqr()

gameRunning = True
while gameRunning:

    background = screen.fill((0,100,140))
    
    #draw lines for grid
    for i in range(5):
        pygame.draw.rect(screen,(line[i],5,800))

    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            gameRunning = False

    #square
    square.drawSquare(square.colour,square.X,square.Y)
    square.numberTextFunc(square.X,square.Y)
    square.OnScreen = True

    square.Y += 1

    if square.Y >= 680:
        square.Y = 680

    pygame.display.update()

解决方法

使用 pygame.Surface.get_rect 获取文本矩形。 pygame.Surface.get_rect.get_rect() 返回一个具有 Surface 对象大小的矩形，该矩形始终从 (0,0) 开始。将文本矩形的中心设置为正方形的中心。使用文本 reectnagle blit 文本。 blit 的第二个参数是元组 (x,y) 或矩形。对于矩形，只考虑矩形的左上角。因此，您可以将文本矩形直接传递给 blit:

class sqr:
    # [...]

    def numberTextFunc(self,X,Y):
        numberText = self.numberFont.render(f"{self.number}",True,(87,63,63))
        rect = pygame.Rect(X,Y,120,120)
        textRect = numberText.get_rect(center = rect.center)
        screen.blit(numberText,textRect)

---

您可以简化代码。 X 和 Y 是对象的属性。因此不需要将坐标传递给方法：

class sqr:
    def __init__(self):
        self.colours = [(255,0),(0,255,255)]
        self.Xpositions = [0,125,245,365,485]
        self.OnScreen = False
        self.X = random.choice(self.Xpositions) 
        self.Y = 0
        self.colour = random.choice(self.colours)
        self.number = random.choice([20,40,80])
        self.numberFont =  pygame.font.Font("TitilliumWeb-Black.ttf",48)

    def drawSquare(self,colour):
        pygame.draw.rect(screen,colour,(self.X,self.Y,120))

    def numberTextFunc(self):
        numberText = self.numberFont.render(f"{self.number}",63))
        rect = pygame.Rect(self.X,textRect)

gameRunning = True
while gameRunning:

    background = screen.fill((0,100,140))

    #draw lines for grid
    for i in range(5):
        pygame.draw.rect(screen,(line[i],5,800))

    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            gameRunning = False

    #square
    square.drawSquare(square.colour)
    square.numberTextFunc()
    square.OnScreen = True

    square.Y += 1
    if square.Y >= 680:
        square.Y = 680

    pygame.display.update()