如何从其他函数接收更新的变量？

Question

所以在我的游戏中，我试图建立一个评分系统，每次击中敌人时，你的分数都会增加 1。但是，分数似乎没有更新，我不确定为什么以及如何解决它。如果可能的话，我不想使用全局变量，因为我的讲师鼓励我们反对它。

这里是所有相关代码（我已经标记了提到分数变量的位置）：

main():

def main():
    font = pygame.font.SysFont("28 Days Later", 35, True, False) # (Font name, Font size, Bold?, Italic?)
    board = player(225, 225, 64, 64, 0)
    DiArrow = enemy(100, 410, 48, 48, 410)
    score = 0 # <------------- SCORE
    bullets = []
    E_bullets = []
    while True:
        moveFunctions(board, DiArrow, bullets, E_bullets, score, font) # <------------- SCORE

移动函数：

def moveFunctions(board, DiArrow, bullets, E_bullets, score, font): # <------------- SCORE
    clock = pygame.time.Clock()
    run = True
    while run:
        clock.tick(15) # Frame rate per second (FPS)

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

        fireBullet(board, bullets, DiArrow, score) # <------------- SCORE
        E_fireBullet(board, E_bullets, DiArrow)

        arrowKeys = pygame.key.get_pressed()

        bulletDirection(arrowKeys, board, bullets)
        E_bulletDirection(DiArrow, E_bullets, board)
        playerControls(arrowKeys, board)
        enemyControls(DiArrow, board)
        redrawGameWindow(board, DiArrow, bullets, E_bullets, font, score) # <------------- SCORE

fireBullet():

def fireBullet(board, bullets, DiArrow, score): # <------------- SCORE
    if board.lastDirection == "left":
        for bullet in bullets:
            if bullet.y - bullet.radius < DiArrow.hitbox[1] + DiArrow.hitbox[3] and bullet.y + bullet.radius > \
                    DiArrow.hitbox[1]:
                if bullet.x + bullet.radius > DiArrow.hitbox[0] and bullet.x - bullet.radius < DiArrow.hitbox[0] + \
                        DiArrow.hitbox[2]:
                    DiArrow.getHit()
                    score += 1 # <------------- SCORE
                    bullets.pop(bullets.index(bullet))
            if bullet.x < 500 and bullet.x > 50:
                bullet.x += bullet.vel
            else:
                bullets.pop(bullets.index(bullet))
    elif board.lastDirection == "right":
        for bullet in bullets:
            if bullet.y - bullet.radius < DiArrow.hitbox[1] + DiArrow.hitbox[3] and bullet.y + bullet.radius > \
                    DiArrow.hitbox[1]:
                if bullet.x + bullet.radius > DiArrow.hitbox[0] and bullet.x - bullet.radius < DiArrow.hitbox[0] + \
                        DiArrow.hitbox[2]:
                    DiArrow.getHit()
                    score += 1 # <------------- SCORE
                    bullets.pop(bullets.index(bullet))
            if bullet.x < 450 and bullet.x > 0:
                bullet.x += bullet.vel
            else:
                bullets.pop(bullets.index(bullet))
    elif board.lastDirection == "up":
        for bullet in bullets:
            if bullet.y - bullet.radius < DiArrow.hitbox[1] + DiArrow.hitbox[3] and bullet.y + bullet.radius > \
                    DiArrow.hitbox[1]:
                if bullet.x + bullet.radius > DiArrow.hitbox[0] and bullet.x - bullet.radius < DiArrow.hitbox[0] + \
                        DiArrow.hitbox[2]:
                    DiArrow.getHit()
                    score += 1 # <------------- SCORE
                    bullets.pop(bullets.index(bullet))
            if 500 > bullet.y > 50:
                bullet.y += bullet.vel
            else:
                bullets.pop(bullets.index(bullet))
    else:
        for bullet in bullets:
            if bullet.y - bullet.radius < DiArrow.hitbox[1] + DiArrow.hitbox[3] and bullet.y + \
                bullet.radius > DiArrow.hitbox[1]:
                if bullet.x + bullet.radius > DiArrow.hitbox[0] and bullet.x - bullet.radius < \
                    DiArrow.hitbox[0] + DiArrow.hitbox[2]:
                    DiArrow.getHit()
                    score += 1 # <------------- SCORE
                    bullets.pop(bullets.index(bullet))
            if 450 > bullet.y > 0:
                bullet.y += bullet.vel
            else:
                bullets.pop(bullets.index(bullet))
    # return score <------------------ I tried using return here but to no avail

redrawGameWindow():

def redrawGameWindow(board, DiArrow, bullets, E_bullets, font, score): # <------------- SCORE
    window.blit(bg, (0,0))
    text = font.render("Score: " + str(score), 1, (255, 255, 255)) # <------------- SCORE
    window.blit(text, (380, 515))
    board.drawCharacter(window)
    DiArrow.drawEnemy(window)
    for bullet in bullets:
        bullet.draw(window)
    for bullet in E_bullets:
        bullet.draw(window)
    pygame.display.update()

我应该提到，除了分数之外，一切都在正常工作，并且我正在使用 Pygame 模块（尽管这里的问题与任何 Pygame 函数无关）。此外，棋盘代表玩家，而 DiArrow 代表敌人。

感谢任何可以帮助阐明我的问题的人，祝大家度过愉快的一天

Answer 1

事实上，如果您对每个使用score 的函数都执行此操作，那么您从函数返回score 的尝试应该可以工作，但是您还必须按顺序保存每次调用使用它的每个函数的返回值在函数调用之间传播更新的值。修改您的代码以满足以下格式，您应该会实现所需的行为。

def functionThatUsesScore(score):
    score += 1
    return score


def functionThatDoesNotUseScore():
    pass


def anotherFunctionThatUsesScore(score):
    score += 2
    return score


def main():
    score = 0
    while True:
        score = functionThatUsesScore(score)
        functionThatDoesNotUseScore()
        score = anotherFunctionThatUsesScore(score)