当我尝试将精灵添加到屏幕时，PyGame 滞后

Question

我正在尝试在 PyGame 中进行外星人入侵，当我 blit 飞船和子弹一切正常时，但当我尝试从精灵组中绘制外星人时，游戏突然卡住了。我尝试过使用 convert() 函数，但即使使用它仍然滞后。 主要：

 import sys
    import pygame
    from settings import Settings
    from ship import Ship
    from bullet import Bullet 
    from alien import Alien 
    
    
    class AlienInvasion:
        """Overall class to manage game assests and behavior"""
        def __init__(self):
            """Initialize the game and create resources"""
            pygame.init()
            self.settings = Settings()
            self.screen = pygame.display.set_mode((self.settings.screen_width, self.settings.screen_height))
    
            
            pygame.display.set_caption("Alien Invasion")
    
            self.ship = Ship(self)
            self.bullets = pygame.sprite.Group()
            self.aliens = pygame.sprite.Group()
    
    
        def run_game(self):
            """Start the main loop for the game"""
            while True:
                clock.tick(60)
                self._check_events()
                self.ship.update()
                self._update_bullets()
                self._create_fleet()
                self._update_aliens()
                self._update_screen()
    
        def _check_events(self):
            #watch for keyboard and mouse events
            for event in pygame.event.get():
                if event.type == pygame.QUIT:
                    sys.exit()
                elif event.type == pygame.KEYDOWN:
                    self._check_keydown_events(event)
    
                elif event.type == pygame.KEYUP:
                    self._check_keyup_events(event)
    
        def _check_keydown_events(self, event):
            """Respond to keypress"""
            if event.key == pygame.K_RIGHT:
                self.ship.moving_right = True
            elif event.key == pygame.K_LEFT:
                self.ship.moving_left = True
            elif event.key == pygame.K_UP:
                self.ship.moving_up = True
            elif event.key == pygame.K_DOWN:
                self.ship.moving_down = True 
            elif event.key == pygame.K_q:
                sys.exit()
            elif event.key == pygame.K_SPACE:
                self._fire_bullet()
                self.ship.firing = True
    
    
        def _check_keyup_events(self, event):
            if event.key == pygame.K_RIGHT:
                self.ship.moving_right = False
            elif event.key == pygame.K_LEFT:
                self.ship.moving_left = False
            
    
        def _fire_bullet(self):
            if len(self.bullets) < self.settings.bullets_allowed:
                new_bullet = Bullet(self)
                self.bullets.add(new_bullet)
    
        def _update_bullets(self):
            self.bullets.update()
            #delete bullets
            for bullet in self.bullets.copy():
                if bullet.rect.bottom <= 0:
                    self.bullets.remove(bullet)
    
        def _update_aliens(self):
            """Update position of aliens"""
            self.aliens.update()
    
        def _create_fleet(self):
            alien = Alien(self)
            alien_width,alien_height = alien.rect.size
            available_space_x = self.settings.screen_width - (2 * alien_width)
            number_aliens_x = available_space_x // (2 * alien_width)
            #determine number of rows that fit on the screen
            ship_height = self.ship.rect.height
            available_space_y = self.settings.screen_height - (3*alien_height) - ship_height
            number_aliens_y = available_space_y // (2* alien_height)
            for row_number in range(number_aliens_y):
                for alien_number in range(number_aliens_x):
                    self._create_alien(alien_number, row_number)
    
        def _create_alien(self,alien_number,row_number):
            """Create alien and place it in a row"""
            alien = Alien(self)
            alien_width, alien_height = alien.rect.size
            alien.x = alien_width + 2 * alien_width * alien_number
            alien.rect.y = alien_height + 2 * alien_width * row_number 
            alien.rect.x = alien.x
            self.aliens.add(alien)
            
    
                    
        def _update_screen(self):
            self.screen.fill(self.settings.bg_color)
            self.ship.blitme()
            for bullet in self.bullets.sprites():
                bullet.draw_bullet()
            self._create_fleet()
            self.aliens.draw(self.screen)
    
            pygame.display.flip()
            
    if __name__ == '__main__':
        ai = AlienInvasion()
        ai.run_game(

外星人文件 这是存储外星人的外星人类。我已经将我的图像转换为 .bmp 文件，并且我也尝试过使用 convert() 函数，但它仍然滞后。

import pygame 
from pygame.sprite import Sprite 

class Alien(Sprite):
    """class that represents a single alien in a fleet"""
    def __init__(self, ai_game):
        #intialize alien and set position
        super().__init__()
        self.screen = ai_game.screen
        self.settings = ai_game.settings

        #load alien image
        self.image = pygame.image.load('images/alien.bmp').convert()
        self.rect = self.image.get_rect()

        #start the alien at the top left of the screen
        self.rect.x = self.rect.width
        self.rect.y = self.rect.height

        #store alien exact horizontal position
        self.x = float(self.rect.x)

    def update(self):
        #move alien to the right 
        self.x += self.settings.alien_speed
        self.rect.x = self.x

 

Answer 1

您在每一帧都创建舰队的问题。因此，新的外星人会在每一帧中添加到 Group 中，并且您必须绘制比必要更多的外星人。更糟糕的是，'images/alien.bmp' 是在 Alien 类的构造函数中加载的，因此必须在每一帧中加载多个图像：

class AlienInvasion:
   # [...]

   def _update_screen(self):
       # [...]

       self._create_fleet() # <----
       self.aliens.draw(self.screen) 

---

我建议在构造第一个外星人时将图像加载一次，一次加载到类变量中：
（见Class and Instance Variables）

class Alien(Sprite):
    
    alienimage = None

    """class that represents a single alien in a fleet"""
    def __init__(self, ai_game):
        # [...]

        #load alien image
        if self.alienimage == None:
            self.alienimage = pygame.image.load('images/alien.bmp').convert()
        self.image = self.alienimage

        # [...]

在主应用循环之前创建队列：

class AlienInvasion:
    # [...]
    
    def run_game(self):
        
        self._create_fleet() # <---- ADD

        """Start the main loop for the game"""
        while True:
            clock.tick(60)
            self._check_events()
            self.ship.update()
            self._update_bullets()
            # self._create_fleet() <---- DELETE
            self._update_aliens()
            self._update_screen()

    # [...]

    def _update_screen(self):
       # [...]

       # self._create_fleet() <---- DELETE
       self.aliens.draw(self.screen)