Pygame开发太空射击游戏时，松开空格键子弹无法持续飞行还跟随玩家移动如何解决

• 子弹松开空格就停止飞行：你仅在检测到空格键被按住时才更新子弹Y轴坐标，松开按键后更新逻辑终止，子弹自然停止移动
• 子弹跟随玩家横向偏移：你在玩家左右移动的逻辑中同步修改了子弹的X轴坐标，相当于把子弹和玩家做了位置绑定，飞行过程中也会跟着玩家移动

1. 新增bullet_fired状态变量，标记当前是否有子弹处于飞行状态，初始值为False
2. 删除玩家左右移动逻辑中修改playerBulletX的代码，子弹射出后X轴坐标固定不再变化
3. 调整空格键触发逻辑：按下空格且当前无子弹飞行时，初始化子弹坐标并标记为已发射
4. 新增独立的子弹飞行更新逻辑：只要子弹处于发射状态，每帧都自动更新Y轴坐标，飞出屏幕顶部后重置发射状态

import pygame
# initialize the pygame
pygame.init()

# create the screen
screen = pygame.display.set_mode((800, 600))

# Title and icon
pygame.display.set_caption("Space Invaders")
icon = pygame.image.load('Invader2.xcf')
pygame.display.set_icon(icon)

# Player
playerImg = pygame.image.load('Player.xcf')
player_big = pygame.transform.scale(playerImg, (48, 48))
playerX = 370
playerY = 480
vel = 0.15

# Player Bullets
playerBulletImg = pygame.image.load('Player_bullet.xcf')
playerBulletX = 0
playerBulletY = 0
bulletVel = 0.5
# 新增子弹发射状态
bullet_fired = False


def player(x, y):
    screen.blit(player_big, (x, y))


def bullet(x, y):
    screen.blit(playerBulletImg, (x, y))


# Game Loop
running = True

while running:

    # RGB 注：pygame RGB取值范围为0-255，已将原小数参数转换为对应整数
    screen.fill((48, 213, 200))

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

    keys = pygame.key.get_pressed()

    # 玩家移动逻辑，不再修改子弹X坐标
    if keys[pygame.K_LEFT] and playerX > 0:
        playerX -= vel
    if keys[pygame.K_RIGHT] and playerX < 800 - 48:
        playerX += vel
    
    # 空格发射逻辑：只有未发射状态才触发
    if keys[pygame.K_SPACE] and not bullet_fired:
        playerBulletX = playerX + 16
        playerBulletY = playerY + 10
        bullet_fired = True
    
    # 子弹独立飞行逻辑，和按键状态无关
    if bullet_fired:
        playerBulletY -= bulletVel
        # 子弹飞出屏幕顶部就重置状态
        if playerBulletY <= 0:
            bullet_fired = False
        else:
            bullet(playerBulletX, playerBulletY)
    
    player(playerX, playerY)

    pygame.display.update()

内容的提问来源于stack exchange，提问作者Elijah Abdella