python飞机大战12-血条恢复

让玩家变得更强，增加2种道具：

• 盾牌：一种能够恢复血条的物体
• 枪：一个会增加火力的物体

1 pow精灵

   首先，需要定义另一个Sprite，这次代表powerup（力量加强）对象。为了简单起见，可以复制 Bullet() 的类型定义，然后进行一些更改，因为它们行为类似：对于它的图片形象，将随机选择 'gun' 和之间 'shield' ，这将是两种力量加强。

class Pow(pygame.sprite.Sprite):
    def __init__(self,center):
        pygame.sprite.Sprite.__init__(self)
        self.type = random.choice(['shield', 'gun'])
        self.image = pygame.transform.scale(powerup_images[self.type], (30, 30))
        self.image.set_colorkey(BLACK)
        self.rect = self.image.get_rect()
        self.rect.center = center
        self.speedy = 3

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

需要在资源加载部分加载新图像，使用字典来保存图像：

powerup_images = {}
powerup_images['shield'] = pygame.image.load(path.join(img_dir,'shield.png')).convert()
powerup_images['gun'] = pygame.image.load(path.join(img_dir,'gun.png')).convert()

2 生产道具

   为了产生它们，需要一个组来保存它们（用于碰撞）：

powerups = pygame.sprite.Group()

然后，当子弹摧毁一个怪物时，想要一个（小）随机的机会，生成一个力量加强对象：

# check to see if a bullet hit a mob
hits = pygame.sprite.groupcollide(mobs, bullets, True, True, pygame.sprite.collide_rect_ratio(0.6))
for hit in hits:
    score += 100 - hit.leng
    random.choice(expl_sounds).play()
    expl = Explosion(hit.rect.center, 'lg')
    all_sprites.add(expl)
    if random.random() > 0.9:
        pow = Pow(hit.rect.center)
        all_sprites.add(pow)
        powerups.add(pow)
    newmob()

在这里， random.random() 选择一个介于0和1之间的随机十进制数，因此只有当数字大于0.9时才产生，这意味着有10％的几率从被毁坏的流星上掉下奖励。

3 与玩家碰撞

现在，需要另一次碰撞检查，这次是在玩家和道具组之间。

# check to see if player hit a powerup
hits = pygame.sprite.spritecollide(player,powerups,True,pygame.sprite.collide_rect_ratio(0.6))
for hit in hits:
    if hit.type == 'shield':
        player.shield += random.randrange(10, 30)
        if player.shield >= 100:
            player.shield = 100
        if hit.type == 'gun':
            pass

整合到一起

# Shmup game - part 12
# shmup.py
# 血条恢复
import pygame
import random
from os import path


img_dir = path.join(path.dirname(__file__), 'img')
mp3_dir = path.join(path.dirname(__file__), 'mp3')


WIDTH = 512  # width of our game window
HEIGHT = 768  # height of our game window
FPS = 60  # 60 frames per second


# Colors(R,G,B),define color
BLACK = (0, 0, 0)
WHITE = (255, 255, 255)
RED = (255, 0, 0)
GREEN = (0, 255, 0)
BLUE = (0, 0, 255)
YELLOW = (255, 255, 0)


# initialize pygame and create windw
pygame.init()  # 启动pygame并初始化
pygame.mixer.init()  # 声音初始化
screen = pygame.display.set_mode((WIDTH, HEIGHT))  # 游戏屏幕，按照在配置常量中设置的大小创建
pygame.display.set_caption("Shmup!")
icon = pygame.image.load("img/alien.ico")
pygame.display.set_icon(icon)
clock = pygame.time.Clock()  # 创建一个时钟以便于确保游戏能以指定的FPS运行


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)  # 第4个参数默认值为0，表示填充矩形内部

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, (60, 40))
        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.speedy = 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

        # any code here will happen every time the game loop updates
        self.speedx = 0
        self.speedy = 0
        keystate = pygame.key.get_pressed()
        if keystate[pygame.K_LEFT]:
            self.speedx = -5
        if keystate[pygame.K_RIGHT]:
            self.speedx = 5
        self.rect.x += self.speedx

        if keystate[pygame.K_UP]:
            self.speedy = -5
        if keystate[pygame.K_DOWN]:
            self.speedy = 5
        self.rect.y += self.speedy

        if keystate[pygame.K_SPACE]:
            self.shoot()

        if self.rect.right > WIDTH:
            self.rect.right = WIDTH
        if self.rect.left < 0:
            self.rect.left = 0

        if self.rect.bottom > HEIGHT:
            self.rect.bottom = HEIGHT
        if self.rect.top < 0:
            self.rect.top = 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-10)


class Mob(pygame.sprite.Sprite):
    def __init__(self):
        pygame.sprite.Sprite.__init__(self)
        self.leng = random.randrange(30, 70, 10)
        self.image_orig = pygame.transform.scale(random.choice(meteor_img), (self.leng, self.leng))
        self.image_orig.set_colorkey(BLACK)
        self.image = self.image_orig.copy()
        self.rect = self.image.get_rect()
        self.radius = int(self.rect.width / 2)
        # pygame.draw.circle(self.image, RED, self.rect.center, self.radius)
        self.rect.x = random.randrange(WIDTH - self.rect.width)
        self.rect.y = random.randrange(-150, -100)
        self.speedx = random.randrange(-3, 3)
        self.speedy = random.randrange(1, 5)
        self.rot = 0
        self.rot_speed = random.randrange(-8, 8)
        self.last_update = pygame.time.get_ticks()

    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 < -50 or self.rect.right > WIDTH + 50:
            self.rect.x = random.randrange(WIDTH - self.rect.width)
            self.rect.y = random.randrange(-100, -40)
            self.speedy = random.randrange(1, 5)

    def rotate(self):
        now = pygame.time.get_ticks()
        if now - self.last_update > 50:
            self.last_update = now
            # do rotate here
            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


class Bullet(pygame.sprite.Sprite):
    def __init__(self, x, y):
        pygame.sprite.Sprite.__init__(self)
        self.image = pygame.transform.scale(bullet_img, (48, 48))
        self.image.set_colorkey(BLACK)
        self.rect = self.image.get_rect()
        self.rect.bottom = y
        self.rect.centerx = x
        self.speedy = -8

    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 Pow(pygame.sprite.Sprite):
    def __init__(self, center):
        pygame.sprite.Sprite.__init__(self)
        self.type = random.choice(['shield', 'gun'])
        self.image = pygame.transform.scale(powerup_images[self.type], (30, 30))
        self.image.set_colorkey(BLACK)
        self.rect = self.image.get_rect()
        self.rect.center = center
        self.speedy = 3

    def update(self):
        self.rect.y += self.speedy
        # kill if it moves off the bottom of the screen
        if self.rect.top > HEIGHT:
            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 = 50

    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, 'background2.jpg')).convert()
background_rect = background.get_rect()
player_img = pygame.image.load(path.join(img_dir, 'my_plane.png')).convert()
player_mini_img = pygame.transform.scale(player_img,(24,16))
player_mini_img.set_colorkey(BLACK)
bullet_img = pygame.image.load(path.join(img_dir, 'bullet.png')).convert()
meteor_img = []
meteor_list = ['enemy1.png']
for img in meteor_list:
    meteor_img.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(1,6):
    filename = 'e{}.png'.format(i)
    img = pygame.image.load(path.join(img_dir, filename)).convert()
    img.set_colorkey(BLACK)
    img_lg = pygame.transform.scale(img, (Mob().leng + 5, Mob().leng + 5))
    explosion_anim['lg'].append(img_lg)
    img_sm = pygame.transform.scale(img, (16, 16))
    explosion_anim['sm'].append(img_sm)

    filename = 'e{}.png'.format(i)
    img = pygame.image.load(path.join(img_dir, filename)).convert()
    img.set_colorkey(BLACK)
    img_player = pygame.transform.scale(img, (50, 50))
    explosion_anim['player'].append(img_player)
powerup_images = {}
powerup_images['shield'] = pygame.image.load(path.join(img_dir,'shield.PNG')).convert()
powerup_images['gun'] = pygame.image.load(path.join(img_dir,'gun.PNG')).convert()


# load all game sound
shoot_sound = pygame.mixer.Sound(path.join(mp3_dir, 'hero_fire.wav'))
expl_sounds = []
for expl in ['explosion2.wav','explosion3.wav']:
    expl_sounds.append(pygame.mixer.Sound(path.join(mp3_dir, expl)))
pygame.mixer.music.load(path.join(mp3_dir, 'bgm.mp3'))
pygame.mixer.music.set_volume(0.2)


all_sprites = pygame.sprite.Group()
mobs = pygame.sprite.Group()
bullets = pygame.sprite.Group()
powerups = 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)    # 这是游戏主循环，通过变量running控制，如果需要
    for event in pygame.event.get():
        # check for closing window
        if event.type == pygame.QUIT:
            running = False


    # Update                   # 游戏结束的话直接将running设为False即可
    all_sprites.update()

    # check to see if a bullet hit a mob
    hits = pygame.sprite.groupcollide(mobs, bullets, True, True, pygame.sprite.collide_rect_ratio(0.6))
    for hit in hits:
        score += 100 - hit.leng
        random.choice(expl_sounds).play()
        expl = Explosion(hit.rect.center, 'lg')
        all_sprites.add(expl)
        if True:
            pow = Pow(hit.rect.center)
            all_sprites.add(pow)
            powerups.add(pow)
        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.leng/5
        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)
            player.hide()  # 效果不明显，因为之前已经定义了飞机不能超出屏幕
            player.lives -= 1
            player.shield = 100

    # check to see if player hit a powerup
    hits = pygame.sprite.spritecollide(player,powerups,True,pygame.sprite.collide_rect_ratio(0.6))
    for hit in hits:
        if hit.type == 'shield':
            player.shield += random.randrange(10, 30)
            if player.shield >= 100:
                player.shield = 100
            if hit.type == 'gun':
                pass

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

    # Render(draw)             # 现在还没有确定具体的代码，先用一些基本代码填充，后续再补充
    screen.fill(BLACK)
    screen.blit(background, background_rect)
    all_sprites.draw(screen)
    draw_text(screen, str(score), 18, WIDTH/2, 10)
    draw_text(screen, str(player.shield), 15, 20, 20)
    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()

项目代码可以查看我的github，网址为
alien-invasion