外星人入侵 - Pygame - 外星人离开屏幕
Alien Invasion - Pygame - Aliens going off screen
我正在制作 Python 速成课程书中的外星人入侵游戏项目，并卡在了外星舰队应该向右行驶的部分，直到他们到达屏幕的右边缘，改变方向和往左走，依此类推。
问题是我的外星人确实改变了方向，但只有当方块中的第一个外星人（一直在左边的第一个）撞到屏幕的右边缘时才会改变方向。他右边的所有外星人都从右边缘过去。
它似乎不识别右边外星人的矩形应该首先击中右边缘但只能识别第一个外星人一直在左边的矩形...
1. Starting Position Image
2. The Problem Image
我正在严格按照书中的说明进行操作，现在我已经检查了 3 次问题所在。你能帮我找到问题吗？
alien_invasion.py
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 assets and behavior."""
def __init__(self):
"""Initialize the game, and create game resources."""
pygame.init()
self.settings = Settings()
self.screen = pygame.display.set_mode((0, 0), pygame.FULLSCREEN)
self.settings.screen_width = self.screen.get_rect().width
self.settings.screen_height = self.screen.get_rect().height
pygame.display.set_caption("Alien Invasion")
self.ship = Ship(self)
self.bullets = pygame.sprite.Group()
self.aliens = pygame.sprite.Group()
self._create_fleet()
# Set the background color.
self.bg_color = (230, 230, 230)
def run_game(self):
"""Start the main loop for the game."""
while True:
self._check_events()
self.ship.update()
self._update_bullets()
self._update_aliens()
self._update_screen()
def _check_events(self):
"""Respond to keypresses 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 keypresses."""
if event.key == pygame.K_RIGHT:
# Move the ship to the right.
self.ship.moving_right = True
elif event.key == pygame.K_LEFT:
# Move the ship to the left.
self.ship.moving_left = True
elif event.key == pygame.K_q:
# Exit the game after pressing Q:
sys.exit()
elif event.key == pygame.K_SPACE:
self._fire_bullet()
def _check_keyup_events(self, event):
"""Respond to keypresses."""
if event.key == pygame.K_RIGHT:
# Stop moving the ship to the right.
self.ship.moving_right = False
elif event.key == pygame.K_LEFT:
# Stop moving the ship to the left.
self.ship.moving_left = False
def _fire_bullet(self):
"""Create a new bullet and add it to the bullets group."""
if len(self.bullets) < self.settings.bullets_allowed:
new_bullet = Bullet(self)
self.bullets.add(new_bullet)
def _update_bullets(self):
"""Update position of bullets and get rid of old bullets."""
# Update bullets positions.
self.bullets.update()
# Get rid of bullets that have dissapeared.
for bullet in self.bullets.copy():
if bullet.rect.bottom <= 0:
self.bullets.remove(bullet)
def _update_aliens(self):
"""Check if the fleet is at an edge, then update the positions of all aliens in the fleet."""
self._check_fleet_edges()
"""Update the positios of all aliens in the fleet."""
self.aliens.update()
def _create_fleet(self):
"""Create a fleet of aliens."""
# Create an alien and find the number of aliens in a row.
# Spacing between each alien is equal to one alien width.
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 the number of rows of aliens that fit on the screen.
ship_height = self.ship.rect.height
available_space_y = (self.settings.screen_height - (3 * alien_height) - ship_height)
number_rows = available_space_y // (4 * alien_height)
# Create the full fleet of aliens.
for row_number in range(number_rows):
for alien_number in range(number_aliens_x):
self._create_alien(alien_number, row_number)
def _create_alien(self, alien_number, row_number):
# Create an alien and place it in the row.
alien = Alien(self)
alien_width, alien_height = alien.rect.size
alien.x = alien_width + 4 * alien_width * alien_number
alien.rect.x = alien.x
alien.rect.y = alien.rect.height + 3 * alien.rect.height * row_number
self.aliens.add(alien)
def _check_fleet_edges(self):
"""Respond appropriately if any aliens have reached an edge."""
for alien in self.aliens.sprites():
if alien.check_edges():
self._change_fleet_direction()
break
def _change_fleet_direction(self):
"""Drop the entire fleet and change the fleet's direction."""
for alien in self.aliens.sprites():
alien.rect.y += self.settings.fleet_drop_speed
self.settings.fleet_direction *= -1
def _update_screen(self):
"""Update images on the screen, and flip to the new screen."""
self.screen.fill(self.settings.bg_color)
self.ship.blitme()
for bullet in self.bullets.sprites():
bullet.draw_bullet()
self.aliens.draw(self.screen)
pygame.display.flip()
if __name__ == '__main__':
# Make a game instance, and run the game.
ai = AlienInvasion()
ai.run_game()
settings.py
class Settings:
"""A class to store all settings for Alien Invasion."""
def __init__(self):
"""Initialize the game's settings."""
# Screen settings
self.screen_width = 1200
self.screen_height = 800
self.bg_color = (230, 230, 230)
self.ship_speed = 1.5
# Bullet settings
self.bullet_speed = 1.0
self.bullet_width = 3
self.bullet_height = 15
self.bullet_color = (60, 60, 60)
self.bullets_allowed = 3
# Alien settings
self.alien_speed = 1.0
self.fleet_drop_speed = 10
# fleet_direction of 1 represents right; -1 represents left.
self.fleet_direction = 1
alien.py
import pygame
from pygame.sprite import Sprite
class Alien(Sprite):
"""A class to represent a single alien in the fleet."""
def __init__(self, ai_game):
"""Initialize the alien and set its starting postion."""
super().__init__()
self.screen = ai_game.screen
self.settings = ai_game.settings
# Load the alien image and set its rect attribute.
self.image = pygame.image.load('images/alien.bmp')
self.rect = self.image.get_rect()
# Start each new alien near the top left of the screen.
self.rect.x = self.rect.width
self.rect.y = self.rect.height
# Store the alien's exact horizontal position.
self.x = float(self.rect.x)
def check_edges(self):
"""Return True if an alien is at edge of screen."""
screen_rect = self.screen.get_rect()
if self.rect.right >= screen_rect.right or self.rect.left <= 0:
return True
def update(self):
"""Move the alien right or left."""
self.x += self.settings.alien_speed * self.settings.fleet_direction
self.rect.x = self.x
这是Indentation的事情。您需要找到第一个碰到边缘的外星人，然后打破循环。实际上，你总是在列表中的第一个敌人之后打破循环：
class AlienInvasion:
# [...]
def _check_fleet_edges(self):
"""Respond appropriately if any aliens have reached an edge."""
for alien in self.aliens.sprites():
if alien.check_edges():
self._change_fleet_direction()
#-->| INDENTATION
break
# break <-- DELETE
我正在制作 Python 速成课程书中的外星人入侵游戏项目，并卡在了外星舰队应该向右行驶的部分，直到他们到达屏幕的右边缘，改变方向和往左走，依此类推。
问题是我的外星人确实改变了方向，但只有当方块中的第一个外星人（一直在左边的第一个）撞到屏幕的右边缘时才会改变方向。他右边的所有外星人都从右边缘过去。
它似乎不识别右边外星人的矩形应该首先击中右边缘但只能识别第一个外星人一直在左边的矩形...
1. Starting Position Image
2. The Problem Image
我正在严格按照书中的说明进行操作，现在我已经检查了 3 次问题所在。你能帮我找到问题吗？
alien_invasion.py
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 assets and behavior."""
def __init__(self):
"""Initialize the game, and create game resources."""
pygame.init()
self.settings = Settings()
self.screen = pygame.display.set_mode((0, 0), pygame.FULLSCREEN)
self.settings.screen_width = self.screen.get_rect().width
self.settings.screen_height = self.screen.get_rect().height
pygame.display.set_caption("Alien Invasion")
self.ship = Ship(self)
self.bullets = pygame.sprite.Group()
self.aliens = pygame.sprite.Group()
self._create_fleet()
# Set the background color.
self.bg_color = (230, 230, 230)
def run_game(self):
"""Start the main loop for the game."""
while True:
self._check_events()
self.ship.update()
self._update_bullets()
self._update_aliens()
self._update_screen()
def _check_events(self):
"""Respond to keypresses 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 keypresses."""
if event.key == pygame.K_RIGHT:
# Move the ship to the right.
self.ship.moving_right = True
elif event.key == pygame.K_LEFT:
# Move the ship to the left.
self.ship.moving_left = True
elif event.key == pygame.K_q:
# Exit the game after pressing Q:
sys.exit()
elif event.key == pygame.K_SPACE:
self._fire_bullet()
def _check_keyup_events(self, event):
"""Respond to keypresses."""
if event.key == pygame.K_RIGHT:
# Stop moving the ship to the right.
self.ship.moving_right = False
elif event.key == pygame.K_LEFT:
# Stop moving the ship to the left.
self.ship.moving_left = False
def _fire_bullet(self):
"""Create a new bullet and add it to the bullets group."""
if len(self.bullets) < self.settings.bullets_allowed:
new_bullet = Bullet(self)
self.bullets.add(new_bullet)
def _update_bullets(self):
"""Update position of bullets and get rid of old bullets."""
# Update bullets positions.
self.bullets.update()
# Get rid of bullets that have dissapeared.
for bullet in self.bullets.copy():
if bullet.rect.bottom <= 0:
self.bullets.remove(bullet)
def _update_aliens(self):
"""Check if the fleet is at an edge, then update the positions of all aliens in the fleet."""
self._check_fleet_edges()
"""Update the positios of all aliens in the fleet."""
self.aliens.update()
def _create_fleet(self):
"""Create a fleet of aliens."""
# Create an alien and find the number of aliens in a row.
# Spacing between each alien is equal to one alien width.
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 the number of rows of aliens that fit on the screen.
ship_height = self.ship.rect.height
available_space_y = (self.settings.screen_height - (3 * alien_height) - ship_height)
number_rows = available_space_y // (4 * alien_height)
# Create the full fleet of aliens.
for row_number in range(number_rows):
for alien_number in range(number_aliens_x):
self._create_alien(alien_number, row_number)
def _create_alien(self, alien_number, row_number):
# Create an alien and place it in the row.
alien = Alien(self)
alien_width, alien_height = alien.rect.size
alien.x = alien_width + 4 * alien_width * alien_number
alien.rect.x = alien.x
alien.rect.y = alien.rect.height + 3 * alien.rect.height * row_number
self.aliens.add(alien)
def _check_fleet_edges(self):
"""Respond appropriately if any aliens have reached an edge."""
for alien in self.aliens.sprites():
if alien.check_edges():
self._change_fleet_direction()
break
def _change_fleet_direction(self):
"""Drop the entire fleet and change the fleet's direction."""
for alien in self.aliens.sprites():
alien.rect.y += self.settings.fleet_drop_speed
self.settings.fleet_direction *= -1
def _update_screen(self):
"""Update images on the screen, and flip to the new screen."""
self.screen.fill(self.settings.bg_color)
self.ship.blitme()
for bullet in self.bullets.sprites():
bullet.draw_bullet()
self.aliens.draw(self.screen)
pygame.display.flip()
if __name__ == '__main__':
# Make a game instance, and run the game.
ai = AlienInvasion()
ai.run_game()
settings.py
class Settings:
"""A class to store all settings for Alien Invasion."""
def __init__(self):
"""Initialize the game's settings."""
# Screen settings
self.screen_width = 1200
self.screen_height = 800
self.bg_color = (230, 230, 230)
self.ship_speed = 1.5
# Bullet settings
self.bullet_speed = 1.0
self.bullet_width = 3
self.bullet_height = 15
self.bullet_color = (60, 60, 60)
self.bullets_allowed = 3
# Alien settings
self.alien_speed = 1.0
self.fleet_drop_speed = 10
# fleet_direction of 1 represents right; -1 represents left.
self.fleet_direction = 1
alien.py
import pygame
from pygame.sprite import Sprite
class Alien(Sprite):
"""A class to represent a single alien in the fleet."""
def __init__(self, ai_game):
"""Initialize the alien and set its starting postion."""
super().__init__()
self.screen = ai_game.screen
self.settings = ai_game.settings
# Load the alien image and set its rect attribute.
self.image = pygame.image.load('images/alien.bmp')
self.rect = self.image.get_rect()
# Start each new alien near the top left of the screen.
self.rect.x = self.rect.width
self.rect.y = self.rect.height
# Store the alien's exact horizontal position.
self.x = float(self.rect.x)
def check_edges(self):
"""Return True if an alien is at edge of screen."""
screen_rect = self.screen.get_rect()
if self.rect.right >= screen_rect.right or self.rect.left <= 0:
return True
def update(self):
"""Move the alien right or left."""
self.x += self.settings.alien_speed * self.settings.fleet_direction
self.rect.x = self.x
这是Indentation的事情。您需要找到第一个碰到边缘的外星人，然后打破循环。实际上，你总是在列表中的第一个敌人之后打破循环：
class AlienInvasion:
# [...]
def _check_fleet_edges(self):
"""Respond appropriately if any aliens have reached an edge."""
for alien in self.aliens.sprites():
if alien.check_edges():
self._change_fleet_direction()
#-->| INDENTATION
break
# break <-- DELETE