python飞机大战11 玩家多条命

玩家爆炸

我们将使用不同的爆炸动画来制作玩家的死亡，同样来自同样的Kenny Game Art套装，称为“Sonic Explosion”。

我们只需像其他爆炸那样加载那些帧。我们将添加另一个名为的爆炸类型'player'并将其加载到同一个循环中，因为它与我们加载的另一个爆炸具有相同的帧数。现在我们的加载代码如下所示：

explosion_anim = {}
explosion_anim['lg'] = []
explosion_anim['sm'] = []
explosion_anim['player'] = []
for i in range(9):
    filename = 'regularExplosion0{}.png'.format(i)
    img = pygame.image.load(path.join(img_dir, filename)).convert()
    img.set_colorkey(BLACK)
    img_lg = pygame.transform.scale(img, (75, 75))
    explosion_anim['lg'].append(img_lg)
    img_sm = pygame.transform.scale(img, (32, 32))
    explosion_anim['sm'].append(img_sm)
    filename = 'sonicExplosion0{}.png'.format(i)
    img = pygame.image.load(path.join(img_dir, filename)).convert()
    img.set_colorkey(BLACK)
    explosion_anim['player'].append(img)

我们不需要更改Explosionsprite类中的任何内容，因此我们只需要在玩家的盾牌耗尽时创建玩家爆炸。我们可以在我们检查玩家与流星碰撞的游戏循环中添加：

# check to see if a mob hit the player
hits = pygame.sprite.spritecollide(player, mobs, True, pygame.sprite.collide_circle)
for hit in hits:
    player.shield -= hit.radius * 2
    expl = Explosion(hit.rect.center, 'sm')
    all_sprites.add(expl)
    newmob()
    if player.shield <= 0:
        death_explosion = Explosion(player.rect.center, 'player')
        all_sprites.add(death_explosion)
        running = False

但是，如果你运行程序，你会看到我们现在有一个问题：当玩家死亡时，我们设置running以False使游戏结束，我们有机会看到我们的漂亮爆炸之前！

要解决这个问题，我们需要在爆炸完成之前不要结束游戏。所以我们将删除播放器，但running在爆炸消失之前不会设置：

    if player.shield <= 0:
        death_explosion = Explosion(player.rect.center, 'player')
        all_sprites.add(death_explosion)
        player.kill()

# if the player died and the explosion has finished playing
if not player.alive() and not death_explosion.alive():
    running = False

该alive()函数只返回特定精灵是否存活。由于我们kill()在完成比赛时爆炸，我们现在可以在比赛结束时结束比赛。

生命

现在我们将为玩家提供多条生命。我们可以使用变量跟踪它，但我们也希望能够在屏幕上显示它。如果我们使用较小的玩家船只图像来表示剩下多少生命，那么它不会只显示一个数字，而是会更好看。首先，我们将创建较小的图像：

player_img = pygame.image.load(path.join(img_dir, "playerShip1_orange.png")).convert()
player_mini_img = pygame.transform.scale(player_img, (25, 19))
player_mini_img.set_colorkey(BLACK)

现在我们将在Player类中添加一些新参数__init__()：生命计数器，一个标记（可以是True或者变量False）隐藏/显示玩家，以及一个控制玩家隐藏时间的计时器：

self.lives = 3
self.hidden = False
self.hide_timer = pygame.time.get_ticks()

现在，当玩家死亡而不是使用时kill()，我们将隐藏玩家并从中减去1 lives。我们还为下一次生命重置盾牌：

if player.shield <= 0:
        death_explosion = Explosion(player.rect.center, 'player')
        all_sprites.add(death_explosion)
        player.hide()
        player.lives -= 1
        player.shield = 100

# if the player died and the explosion has finished playing
if player.lives == 0 and not death_explosion.alive():
    running = False

接下来，我们需要定义隐藏的工作原理。回到课堂上，Player()我们将添加一个hide方法，该方法将hidden标志设置为True并启动计时器。我们还需要确保在玩家被隐藏时，它不会被流星击中。我们有几种方法可以做到这一点，但是一个不需要添加/删除组等的简单方法就是暂时将玩家从屏幕底部移开：

def hide(self):
    # hide the player temporarily
    self.hidden = True
    self.hide_timer = pygame.time.get_ticks()
    self.rect.center = (WIDTH / 2, HEIGHT + 200)

在玩家的update()方法中，我们需要取消隐藏是否已经过了足够的时间（我们现在使用1秒）：

def update(self):
    # unhide if hidden
    if self.hidden and pygame.time.get_ticks() - self.hide_timer > 1000:
        self.hidden = False
        self.rect.centerx = WIDTH / 2
        self.rect.bottom = HEIGHT - 10

生命计数器显示

为了显示生命，我们将创建一个类似于我们的功能draw_shield_bar()，这将让我们将生命计数器放在给定的位置：

def draw_lives(surf, x, y, lives, img):
    for i in range(lives):
        img_rect = img.get_rect()
        img_rect.x = x + 30 * i
        img_rect.y = y
        surf.blit(img, img_rect)

我们只是循环次数等于生命的数量，然后将每个图像间隔30个像素（player_mini_img宽度为25像素，这样它们之间会留下一个小空间）。

然后，在我们的游戏循环的绘图部分添加对此函数的调用：

draw_lives(screen, WIDTH - 100, 5, player.lives,
       player_mini_img)

现在我们可以看到最终结果：

image.png

import pygame
import random
from os import path

img_dir = path.join(path.dirname(__file__), 'img')
snd_dir = path.join(path.dirname(__file__), 'snd')

WIDTH = 480
HEIGHT = 600
FPS = 60

# define colors
WHITE = (255, 255, 255)
BLACK = (0, 0, 0)
RED = (255, 0, 0)
GREEN = (0, 255, 0)
BLUE = (0, 0, 255)
YELLOW = (255, 255, 0)

# initialize pygame and create window
pygame.init()
pygame.mixer.init()
screen = pygame.display.set_mode((WIDTH, HEIGHT))
pygame.display.set_caption("Shmup!")
clock = pygame.time.Clock()

font_name = pygame.font.match_font('arial')
def draw_text(surf, text, size, x, y):
    font = pygame.font.Font(font_name, size)
    text_surface = font.render(text, True, WHITE)
    text_rect = text_surface.get_rect()
    text_rect.midtop = (x, y)
    surf.blit(text_surface, text_rect)

def newmob():
    m = Mob()
    all_sprites.add(m)
    mobs.add(m)

def draw_shield_bar(surf, x, y, pct):
    if pct < 0:
        pct = 0
    BAR_LENGTH = 100
    BAR_HEIGHT = 10
    fill = (pct / 100) * BAR_LENGTH
    outline_rect = pygame.Rect(x, y, BAR_LENGTH, BAR_HEIGHT)
    fill_rect = pygame.Rect(x, y, fill, BAR_HEIGHT)
    pygame.draw.rect(surf, GREEN, fill_rect)
    pygame.draw.rect(surf, WHITE, outline_rect, 2)

def draw_lives(surf, x, y, lives, img):
    for i in range(lives):
        img_rect = img.get_rect()
        img_rect.x = x + 30 * i
        img_rect.y = y
        surf.blit(img, img_rect)

class Player(pygame.sprite.Sprite):
    def __init__(self):
        pygame.sprite.Sprite.__init__(self)
        self.image = pygame.transform.scale(player_img, (50, 38))
        self.image.set_colorkey(BLACK)
        self.rect = self.image.get_rect()
        self.radius = 20
        # pygame.draw.circle(self.image, RED, self.rect.center, self.radius)
        self.rect.centerx = WIDTH / 2
        self.rect.bottom = HEIGHT - 10
        self.speedx = 0
        self.shield = 100
        self.shoot_delay = 250
        self.last_shot = pygame.time.get_ticks()
        self.lives = 3
        self.hidden = False
        self.hide_timer = pygame.time.get_ticks()

    def update(self):
        # unhide if hidden
        if self.hidden and pygame.time.get_ticks() - self.hide_timer > 1000:
            self.hidden = False
            self.rect.centerx = WIDTH / 2
            self.rect.bottom = HEIGHT - 10

        self.speedx = 0
        keystate = pygame.key.get_pressed()
        if keystate[pygame.K_LEFT]:
            self.speedx = -8
        if keystate[pygame.K_RIGHT]:
            self.speedx = 8
        if keystate[pygame.K_SPACE]:
            self.shoot()
        self.rect.x += self.speedx
        if self.rect.right > WIDTH:
            self.rect.right = WIDTH
        if self.rect.left < 0:
            self.rect.left = 0

    def shoot(self):
        now = pygame.time.get_ticks()
        if now - self.last_shot > self.shoot_delay:
            self.last_shot = now
            bullet = Bullet(self.rect.centerx, self.rect.top)
            all_sprites.add(bullet)
            bullets.add(bullet)
            shoot_sound.play()

    def hide(self):
        # hide the player temporarily
        self.hidden = True
        self.hide_timer = pygame.time.get_ticks()
        self.rect.center = (WIDTH / 2, HEIGHT + 200)

class Mob(pygame.sprite.Sprite):
    def __init__(self):
        pygame.sprite.Sprite.__init__(self)
        self.image_orig = random.choice(meteor_images)
        self.image_orig.set_colorkey(BLACK)
        self.image = self.image_orig.copy()
        self.rect = self.image.get_rect()
        self.radius = int(self.rect.width * .85 / 2)
        # pygame.draw.circle(self.image, RED, self.rect.center, self.radius)
        self.rect.x = random.randrange(WIDTH - self.rect.width)
        self.rect.bottom = random.randrange(-80, -20)
        self.speedy = random.randrange(1, 8)
        self.speedx = random.randrange(-3, 3)
        self.rot = 0
        self.rot_speed = random.randrange(-8, 8)
        self.last_update = pygame.time.get_ticks()

    def rotate(self):
        now = pygame.time.get_ticks()
        if now - self.last_update > 50:
            self.last_update = now
            self.rot = (self.rot + self.rot_speed) % 360
            new_image = pygame.transform.rotate(self.image_orig, self.rot)
            old_center = self.rect.center
            self.image = new_image
            self.rect = self.image.get_rect()
            self.rect.center = old_center

    def update(self):
        self.rotate()
        self.rect.x += self.speedx
        self.rect.y += self.speedy
        if self.rect.top > HEIGHT + 10 or self.rect.left < -100 or self.rect.right > WIDTH + 100:
            self.rect.x = random.randrange(WIDTH - self.rect.width)
            self.rect.y = random.randrange(-100, -40)
            self.speedy = random.randrange(1, 8)

class Bullet(pygame.sprite.Sprite):
    def __init__(self, x, y):
        pygame.sprite.Sprite.__init__(self)
        self.image = bullet_img
        self.image.set_colorkey(BLACK)
        self.rect = self.image.get_rect()
        self.rect.bottom = y
        self.rect.centerx = x
        self.speedy = -10

    def update(self):
        self.rect.y += self.speedy
        # kill if it moves off the top of the screen
        if self.rect.bottom < 0:
            self.kill()

class Explosion(pygame.sprite.Sprite):
    def __init__(self, center, size):
        pygame.sprite.Sprite.__init__(self)
        self.size = size
        self.image = explosion_anim[self.size][0]
        self.rect = self.image.get_rect()
        self.rect.center = center
        self.frame = 0
        self.last_update = pygame.time.get_ticks()
        self.frame_rate = 75

    def update(self):
        now = pygame.time.get_ticks()
        if now - self.last_update > self.frame_rate:
            self.last_update = now
            self.frame += 1
            if self.frame == len(explosion_anim[self.size]):
                self.kill()
            else:
                center = self.rect.center
                self.image = explosion_anim[self.size][self.frame]
                self.rect = self.image.get_rect()
                self.rect.center = center

# Load all game graphics
background = pygame.image.load(path.join(img_dir, "starfield.png")).convert()
background_rect = background.get_rect()
player_img = pygame.image.load(path.join(img_dir, "playerShip1_orange.png")).convert()
player_mini_img = pygame.transform.scale(player_img, (25, 19))
player_mini_img.set_colorkey(BLACK)
bullet_img = pygame.image.load(path.join(img_dir, "laserRed16.png")).convert()
meteor_images = []
meteor_list = ['meteorBrown_big1.png', 'meteorBrown_med1.png', 'meteorBrown_med1.png',
               'meteorBrown_med3.png', 'meteorBrown_small1.png', 'meteorBrown_small2.png',
               'meteorBrown_tiny1.png']
for img in meteor_list:
    meteor_images.append(pygame.image.load(path.join(img_dir, img)).convert())
explosion_anim = {}
explosion_anim['lg'] = []
explosion_anim['sm'] = []
explosion_anim['player'] = []
for i in range(9):
    filename = 'regularExplosion0{}.png'.format(i)
    img = pygame.image.load(path.join(img_dir, filename)).convert()
    img.set_colorkey(BLACK)
    img_lg = pygame.transform.scale(img, (75, 75))
    explosion_anim['lg'].append(img_lg)
    img_sm = pygame.transform.scale(img, (32, 32))
    explosion_anim['sm'].append(img_sm)
    filename = 'sonicExplosion0{}.png'.format(i)
    img = pygame.image.load(path.join(img_dir, filename)).convert()
    img.set_colorkey(BLACK)
    explosion_anim['player'].append(img)

# Load all game sounds
shoot_sound = pygame.mixer.Sound(path.join(snd_dir, 'pew.wav'))
expl_sounds = []
for snd in ['expl3.wav', 'expl6.wav']:
    expl_sounds.append(pygame.mixer.Sound(path.join(snd_dir, snd)))
player_die_sound = pygame.mixer.Sound(path.join(snd_dir, 'rumble1.ogg'))
pygame.mixer.music.load(path.join(snd_dir, 'tgfcoder-FrozenJam-SeamlessLoop.ogg'))
pygame.mixer.music.set_volume(0.4)

all_sprites = pygame.sprite.Group()
mobs = pygame.sprite.Group()
bullets = pygame.sprite.Group()
player = Player()
all_sprites.add(player)
for i in range(8):
    newmob()

score = 0
pygame.mixer.music.play(loops=-1)
# Game loop
running = True
while running:
    # keep loop running at the right speed
    clock.tick(FPS)
    # Process input (events)
    for event in pygame.event.get():
        # check for closing window
        if event.type == pygame.QUIT:
            running = False

    # Update
    all_sprites.update()

    # check to see if a bullet hit a mob
    hits = pygame.sprite.groupcollide(mobs, bullets, True, True)
    for hit in hits:
        score += 50 - hit.radius
        random.choice(expl_sounds).play()
        expl = Explosion(hit.rect.center, 'lg')
        all_sprites.add(expl)
        newmob()

    # check to see if a mob hit the player
    hits = pygame.sprite.spritecollide(player, mobs, True, pygame.sprite.collide_circle)
    for hit in hits:
        player.shield -= hit.radius * 2
        expl = Explosion(hit.rect.center, 'sm')
        all_sprites.add(expl)
        newmob()
        if player.shield <= 0:
            player_die_sound.play()
            death_explosion = Explosion(player.rect.center, 'player')
            all_sprites.add(death_explosion)
            player.hide()
            player.lives -= 1
            player.shield = 100

    # if the player died and the explosion has finished playing
    if player.lives == 0 and not death_explosion.alive():
        running = False

    # Draw / render
    screen.fill(BLACK)
    screen.blit(background, background_rect)
    all_sprites.draw(screen)
    draw_text(screen, str(score), 18, WIDTH / 2, 10)
    draw_shield_bar(screen, 5, 5, player.shield)
    draw_lives(screen, WIDTH - 100, 5, player.lives, player_mini_img)
    # *after* drawing everything, flip the display
    pygame.display.flip()

pygame.quit()

在下一课中，我们将为游戏添加一些加电。