pygame太空入侵者多重子弹

Question

我刚接触Python，正在尝试制作一个小的太空入侵者游戏。我的问题是，屏幕上不能同时出现超过一颗子弹。我希望能像原版游戏那样，至少发射三颗子弹。有什么好的方法可以做到这一点呢？

这是我的代码：

from pygame import *
import random

class Sprite:

        def __init__(self, xpos, ypos, filename):
                self.x = xpos
                self.y = ypos
                self.bitmap = image.load(filename)
                self.bitmap.set_colorkey((0,0,0))
        def set_position(self, xpos, ypos):
                self.x = xpos
                self.y = ypos
        def render(self):
                screen.blit(self.bitmap, (self.x, self.y))

def Intersect(s1_x, s1_y, s2_x, s2_y):
        if (s1_x > s2_x - 30) and (s1_x < s2_x + 30) and (s1_y > s2_y - 30) and (s1_y < s2_y + 30):
                return 1
        else:
                return 0

init()
screen = display.set_mode((640,480))
key.set_repeat(1, 1)
display.set_caption('PyInvaders')
backdrop = image.load('data/backdrop.bmp') 
enemies = []

x = 0
count = 0

for count in range(10):
    if count < 10:
        enemies.append(Sprite(50 * x + 50, 50, 'data/baddie.bmp'))
        x += 1
        count += 1
    else:
        x = 0
        enemies.append(Sprite(100 * x + 100, 50, 'data/baddie.bmp'))
        x += 1





hero = Sprite(20, 400, 'data/hero.bmp')
ourmissile = Sprite(0, 480, 'data/heromissile.bmp')
enemymissile = Sprite(0, 480, 'data/baddiemissile.bmp')
gameover = image.load('data/gameover.bmp')



quit = 0
enemyspeed = 4
timer = 0        


while quit == 0:

        heromid = hero.x + 16
        screen.blit(backdrop, (0, 0))

        for count in range(len(enemies)):
                enemies[count].x += enemyspeed
                enemies[count].render()

        if enemies[len(enemies)-1].x > 590:
                enemyspeed = -3
                for count in range(len(enemies)):
                        enemies[count].y += 5

        if enemies[0].x < 10:
                enemyspeed = 3
                for count in range(len(enemies)):
                        enemies[count].y += 5

        if ourmissile.y < 640 and ourmissile.y > 0:
            ourmissile.render()
            ourmissile.y += -5
            timer  = timer + 1

        if enemymissile.y >= 480 and len(enemies) > 0:
            enemymissile.x = enemies[random.randint(0, len(enemies) - 1)].x + 16
            enemymissile.y = enemies[0].y

        if Intersect(hero.x, hero.y, enemymissile.x, enemymissile.y):
           quit = 1

        for count in range(0, len(enemies)):
            if Intersect(ourmissile.x, ourmissile.y, enemies[count].x, enemies[count].y):
                    del enemies[count]
                    break

        if len(enemies) == 0:
            quit = 1

        for ourevent in event.get():
                if ourevent.type == QUIT:
                        quit = 1
                if ourevent.type == KEYDOWN:
                        if ourevent.key == K_RIGHT and hero.x < 590:
                                hero.x += 5
                        if ourevent.key == K_LEFT and hero.x > 10:
                                hero.x -= 5
                        if ourevent.key == K_SPACE:
                            if timer < 400:
                                timer = 0
                                ourmissile.x = heromid
                                ourmissile.y = hero.y

        enemymissile.render()
        enemymissile.y += 5

        hero.render()

        display.update()
        time.delay(10)


while quit == 1:
    screen.blit(gameover,(0,0))
    display.update()
    if ourevent.type == KEYDOWN:
        if ourevent.key == K_SPACE:
            quit == 0

Answer 1

好吧，直接说吧。你可能需要重新编写大部分代码。这里有个我怎么做的例子：

我创建了一个精灵组（它可以存放多个精灵）

bulletGroup = pygame.sprite.Group()

然后我为子弹做了一个类

# The pygame.sprite.Sprite is necessary
class Bullet(pygame.sprite.Sprite):

def __init__(self, x, y):
    self.x = x
    self.y = y
    # What this line means is that whenever a bullet is created it goes in the group "bulletGroup"
    pygame.sprite.Sprite.__init__(self, bulletGroup) 

现在来创建一个子弹：

# You can execute this same line as many times as you want and the bullets will be seperate
bullet = Bullet(x, y)

如果你需要关于如何移动它们的帮助，告诉我哦，希望这对你有帮助！

我不是想显得刻薄，但我现在真的想提高我的声望呢 :)

Answer 2

与其只用一个导弹，不如做一个导弹列表。这样就不是这样：

if ourevent.key == K_SPACE:
    if timer < 400:
        timer = 0
        ourmissile.x = heromid
        ourmissile.y = hero.y

创建一个新的导弹，并把它加到列表里：

if timer < 400:
    timer = 0
    missiles.append(Sprite(heromid, hero.y, 'data/heromissile.bmp')

添加循环来绘制和移动所有的导弹：

for m in missiles:
    if m.y < 640 and m.y > 0:
        m.render()
        m.y += -5