为什么我的pygame在添加记分板后在启动时显示空白屏幕？Python速成班。外来入侵
这里的初学者需要帮助 我一直在使用pygame关注Python速成课程项目“外星人入侵” 一切都进行得很顺利，直到我在游戏中添加了记分板，现在当我开始游戏时，只显示背景屏幕，屏幕上没有显示我的精灵或播放按钮 但是，如果我用鼠标点击游戏按钮所在的区域，游戏就会开始，一切正常 我已经试着回溯我的步骤，并且已经寻找了几个小时的问题！我的代码跟这本书没什么区别 任何帮助或建议都会很好！谢谢 主脚本为什么我的pygame在添加记分板后在启动时显示空白屏幕？Python速成班。外来入侵,python,python-3.x,pygame,Python,Python 3.x,Pygame,这里的初学者需要帮助 我一直在使用pygame关注Python速成课程项目“外星人入侵” 一切都进行得很顺利，直到我在游戏中添加了记分板，现在当我开始游戏时，只显示背景屏幕，屏幕上没有显示我的精灵或播放按钮 但是，如果我用鼠标点击游戏按钮所在的区域，游戏就会开始，一切正常 我已经试着回溯我的步骤，并且已经寻找了几个小时的问题！我的代码跟这本书没什么区别 任何帮助或建议都会很好！谢谢 主脚本 import pygame from pygame.sprite import Group from s
import pygame
from pygame.sprite import Group
from settings import Settings
from game_stats import GameStats
from scoreboard import Scoreboard
from button import Button
from ship import Ship
from alien import Alien
import game_functions as gf
def run_game():
# Initialize pygame, settings and screen object.
pygame.init()
ai_settings = Settings()
screen = pygame.display.set_mode(
(ai_settings.screen_width, ai_settings.screen_height))
pygame.display.set_caption("Alien Invasion")
# Make the Play button.
play_button = Button(ai_settings, screen, "Play")
# Create an instance to store game statistics and create a scoreboard.
stats = GameStats(ai_settings)
sb = Scoreboard(ai_settings, screen, stats)
# Make a ship, a group of bullets, and a group of aliens.
ship = Ship(ai_settings, screen)
bullets = Group()
aliens = Group()
# Create the fleet of aliens.
gf.create_fleet(ai_settings, screen, ship, aliens)
# Start the main loop for the game.
while True:
gf.check_events(ai_settings, screen, stats, play_button, ship,
aliens, bullets)
if stats.game_active:
ship.update()
gf.update_bullets(ai_settings, screen, stats, sb, ship, aliens,
bullets)
gf.update_aliens(ai_settings, stats, screen, ship, aliens, bullets)
gf.update_screen(ai_settings, screen, stats, sb, ship, aliens,
bullets, play_button)
run_game()
import pygame
from pygame.sprite import Sprite
class Bullet(Sprite):
"""A class to manage bullets fired from the ship"""
def __init__(self, ai_settings, screen, ship):
""" Create a bullet object from the ships current position"""
super(Bullet, self).__init__()
self.screen = screen
# Creat a bullet rect at (0, 0) and then set correct position.
self.rect = pygame.Rect(0, 0, ai_settings.bullet_width,
ai_settings.bullet_height)
self.rect.centerx = ship.rect.centerx
self.rect.top = ship.rect.top
# Store the bullets position as a decimal value
self.y = float(self.rect.y)
self.color = ai_settings.bullet_color
self.speed_factor = ai_settings.bullet_speed_factor
def update(self):
"""Move the bullet up the screen."""
# Update the decimal position of the bullet.
self.y -= self.speed_factor
# Update the rect position
self.rect.y = self.y
def draw_bullet(self):
""" Draw the bullet to the screen."""
pygame.draw.rect(self.screen, self.color, self.rect)
import sys
from time import sleep
import pygame
from bullet import Bullet
from alien import Alien
def check_keydown_events(event, ai_settings, screen, ship, bullets):
"""Respond to keypresses."""
if event.key == pygame.K_RIGHT:
ship.moving_right = True
elif event.key == pygame.K_LEFT:
ship.moving_left = True
elif event.key == pygame.K_SPACE:
fire_bullet(ai_settings, screen, ship, bullets)
elif event.key == pygame.K_q:
sys.exit()
def fire_bullet(ai_settings, screen, ship, bullets):
"""Fire a bullet if limit not reached yet."""
# Create a new bullet and add it to the bullets group.
if len(bullets) < ai_settings.bullets_allowed:
new_bullet = Bullet(ai_settings, screen, ship)
bullets.add(new_bullet)
def check_keyup_events(event, ship):
"""Respond to key releases.)"""
if event.key == pygame.K_RIGHT:
ship.moving_right = False
elif event.key == pygame.K_LEFT:
ship.moving_left = False
def check_events(ai_settings, screen, stats, play_button, ship, aliens,
bullets):
"""Respond to keypresses and mouse events."""
for event in pygame.event.get():
if event.type == pygame.QUIT:
sys.exit()
elif event.type == pygame.KEYDOWN:
check_keydown_events(event, ai_settings, screen, ship, bullets)
elif event.type == pygame.KEYUP:
check_keyup_events(event, ship)
elif event.type == pygame.MOUSEBUTTONDOWN:
mouse_x, mouse_y = pygame.mouse.get_pos()
check_play_button(ai_settings, screen, stats, play_button, ship,
aliens, bullets, mouse_x, mouse_y)
def check_play_button(ai_settings, screen, stats, play_button, ship, aliens,
bullets, mouse_x, mouse_y):
"""Start new game when the player clicks Play."""
button_clicked = play_button.rect.collidepoint(mouse_x, mouse_y)
if button_clicked and not stats.game_active:
# Reset the game statistics
ai_settings.initialize_dynamic_settings()
# Hide the mouse cursor.
pygame.mouse.set_visible(False)
# Reset the game statistics.
stats.reset_stats()
stats.game_active = True
# Empty the list of aliens and bullets.
aliens.empty()
bullets.empty()
# Create a new fleet and center the ship.
create_fleet(ai_settings, screen, ship, aliens)
ship.center_ship()
def update_screen(ai_settings, screen, stats, sb, ship, aliens, bullets,
play_button):
"""Update images on the screen and flip to the new screen"""
# Redraw the screen through each pass through the loop.
screen.fill(ai_settings.bg_color)
# Redraw all bullets behind ship and aliens.
for bullet in bullets.sprites():
bullet.draw_bullet()
ship.blitme()
aliens.draw(screen)
# Draw the score information.
sb.show_score()
# Draw the play button if the game is inactive.
if not stats.game_active:
play_button.draw_button()
# Make the most recently drawn screen visible.
pygame.display.flip()
def update_bullets(ai_settings, screen, stats, sb, ship, aliens, bullets):
"""Update the position bullets and get rid of old bullets."""
# Update bullet positions.
bullets.update()
# Get rid of bullets that have disapeared.
for bullet in bullets.copy():
if bullet.rect.bottom <= 0:
bullets.remove(bullet)
check_bullet_alien_collisions(ai_settings, screen, stats, sb, ship,
aliens, bullets)
def check_bullet_alien_collisions(ai_settings, screen, stats, sb, ship,
aliens, bullets):
"""Respond to bullet-alien collisions."""
# Remove any bullets and aliens that have collided.
collisions = pygame.sprite.groupcollide(bullets, aliens, True, True)
if collisions:
stats.score += ai_settings.alien_points
sb.prep_score()
if len(aliens) == 0:
# Destroy existing bullets, speed up game, and create new fleet.
bullets.empty()
ai_settings.increase_speed()
create_fleet(ai_settings, screen, ship, aliens)
def get_number_aliens_x(ai_settings, alien_width):
"""Determine the number of aliens that fit in a row."""
available_space_x = ai_settings.screen_width - 2 * alien_width
number_aliens_x = int(available_space_x / (2 * alien_width))
return number_aliens_x
def get_number_rows(ai_settings, ship_height, alien_height):
"""Determine the number of rows of aliens that fit across the screen."""
available_space_y = (ai_settings.screen_height -
(3 * alien_height) - ship_height)
number_rows = int(available_space_y / (2 * alien_height))
return number_rows
def create_alien(ai_settings, screen, aliens, alien_number, row_number):
"""Create an alien and place it in the row."""
# create an alien and place it in the row.
alien = Alien(ai_settings, screen)
alien_width = alien.rect.width
alien.x = alien_width + 2 * alien_width * alien_number
alien.rect.x = alien.x
alien.rect.y = alien.rect.height + 2 * alien.rect.height * row_number
aliens.add(alien)
def create_fleet(ai_settings, screen, ship, aliens):
"""Create full fleet of aliens."""
# Create an alien and find the number of aliens in a row.
alien = Alien(ai_settings, screen)
number_aliens_x = get_number_aliens_x(ai_settings, alien.rect.width)
number_rows = get_number_rows(ai_settings, ship.rect.height,
alien.rect.height)
# Create the fleet of aliens.
for row_number in range(number_rows):
for alien_number in range(number_aliens_x):
create_alien(ai_settings, screen, aliens, alien_number,
row_number)
def check_fleet_edges(ai_settings, aliens):
"""Respond appropriatly if any aliens have reached an edge."""
for alien in aliens.sprites():
if alien.check_edges():
change_fleet_direction(ai_settings, aliens)
break
def change_fleet_direction(ai_settings, aliens):
"""Drop the entire fleet and change the fleet's direction."""
for alien in aliens.sprites():
alien.rect.y += ai_settings.fleet_drop_speed
ai_settings.fleet_direction *= -1
def ship_hit(ai_settings, stats, screen, ship, aliens, bullets):
"""Respond to ship being hit by alien."""
if stats.ships_left > 0:
# Decrement ships_left.
stats.ships_left -= 1
# Empty the list of aliens and bullets.
aliens.empty()
bullets.empty()
# Create a new fleet and center the ship.
create_fleet(ai_settings, screen, ship, aliens)
ship.center_ship()
# Pause
sleep(0.5)
else:
stats.game_active = False
pygame.mouse.set_visible(True)
def check_aliens_bottom(ai_settings, stats, screen, ship, aliens, bullets):
"""Check if any aliens have reached the bottom of the screen."""
screen_rect = screen.get_rect()
for alien in aliens.sprites():
if alien.rect.bottom >= screen_rect.bottom:
# Treat this the same as if the ship got hit.
# Treat this the same as if the ship got hit.
ship_hit(ai_settings, stats, screen, ship, aliens, bullets)
break
def update_aliens(ai_settings, stats, screen, ship, aliens, bullets):
"""
Check if the fleet is at an edge,
and then update the position of all the aliens in the fleet.
"""
check_fleet_edges(ai_settings, aliens)
aliens.update()
# Look for alien-ship collisions.
if pygame.sprite.spritecollideany(ship, aliens):
ship_hit(ai_settings, stats, screen, ship, aliens, bullets)
# Look for aliens hitting the bottom of the screen.
check_aliens_bottom(ai_settings, stats, screen, ship, aliens, bullets)
class Settings():
"""A class to store all settings for Alien Invasion."""
def __init__(self):
"""Initialize the game's static settings."""
# Screen Settings
self.screen_width = 1200
self.screen_height = 600
self.bg_color = (230, 230, 230)
# Ship Settings
self.ship_limit = 3
# Bullet Settings
self.bullet_width = 3
self.bullet_height = 15
self.bullet_color = 60, 60, 60
self.bullets_allowed = 3
# Alien settings
self.fleet_drop_speed = 10
# How quickly the game speeds up
self.speedup_scale = 1.1
# fleet_direction of 1 represents right; -1 represents left.
self.fleet_direction = 1
self.initialize_dynamic_settings()
def initialize_dynamic_settings(self):
"""Initialize settings that change throuhout the game."""
self.ship_speed_factor = 1.5
self.bullet_speed_factor = 3
self.alien_speed_factor = 1
# Fleet_direction of 1 represents right; -1 represents left.
self.fleet_direction = 1
# Scoring
self.alien_points = 50
def increase_speed(self):
"""Increase speed settings."""
self.ship_speed_factor *= self.speedup_scale
self.bullet_speed_factor *= self.speedup_scale
self.alien_speed_factor *= self.speedup_scale
class GameStats():
"""Track statistics for Alien Invasion."""
def __init__(self, ai_settings):
"""Initialize statistics."""
self.ai_settings = ai_settings
self.reset_stats()
# Start the game in an inactive state.
self.game_active = False
# High score should never be reset.
self.high_score = 0
def reset_stats(self):
"""Initialize statistics that can change during the game."""
self.ships_left = self.ai_settings.ship_limit
self.score = 0
import pygame.font
class Scoreboard():
"""A class to report scoring information."""
def __init__(self, ai_settings, screen, stats):
"""Initialize scorekeeping attributes."""
self.screen = screen
self.screen_rect = screen.get_rect()
self.ai_settings = ai_settings
self.stats = stats
# Font settings for the scoring information.
self.text_color = (30, 30, 30)
self.font = pygame.font.SysFont(None, 48)
# Prepare the initial score image.
self.prep_score()
def prep_score(self):
"""Turn the score into a rendered image."""
score_str = str(self.stats.score)
self.score_image = self.font.render(score_str, True, self.text_color,
self.ai_settings.bg_color)
# Display the score at the top of the screen.
self.score_rect = self.score_image.get_rect()
self.score_rect.right = self.screen_rect.right - 20
self.score_rect.top = 20
def show_score(self):
"""Draw score to the screen."""
self.screen.blit(self.score_image, self.score_rect)
import sys
from time import sleep
import pygame
from bullet import Bullet
from alien import Alien
def check_keydown_events(event, ai_settings, screen, ship, bullets):
"""Respond to keypresses."""
if event.key == pygame.K_RIGHT:
ship.moving_right = True
elif event.key == pygame.K_LEFT:
ship.moving_left = True
elif event.key == pygame.K_SPACE:
fire_bullet(ai_settings, screen, ship, bullets)
elif event.key == pygame.K_q:
sys.exit()
def fire_bullet(ai_settings, screen, ship, bullets):
"""Fire a bullet if limit not reached yet."""
# Create a new bullet and add it to the bullets group.
if len(bullets) < ai_settings.bullets_allowed:
new_bullet = Bullet(ai_settings, screen, ship)
bullets.add(new_bullet)
def check_keyup_events(event, ship):
"""Respond to key releases.)"""
if event.key == pygame.K_RIGHT:
ship.moving_right = False
elif event.key == pygame.K_LEFT:
ship.moving_left = False
def check_events(ai_settings, screen, stats, play_button, ship, aliens,
bullets):
"""Respond to keypresses and mouse events."""
for event in pygame.event.get():
if event.type == pygame.QUIT:
sys.exit()
elif event.type == pygame.KEYDOWN:
check_keydown_events(event, ai_settings, screen, ship, bullets)
elif event.type == pygame.KEYUP:
check_keyup_events(event, ship)
elif event.type == pygame.MOUSEBUTTONDOWN:
mouse_x, mouse_y = pygame.mouse.get_pos()
check_play_button(ai_settings, screen, stats, play_button, ship,
aliens, bullets, mouse_x, mouse_y)
def check_play_button(ai_settings, screen, stats, play_button, ship, aliens,
bullets, mouse_x, mouse_y):
"""Start new game when the player clicks Play."""
button_clicked = play_button.rect.collidepoint(mouse_x, mouse_y)
if button_clicked and not stats.game_active:
# Reset the game statistics
ai_settings.initialize_dynamic_settings()
# Hide the mouse cursor.
pygame.mouse.set_visible(False)
# Reset the game statistics.
stats.reset_stats()
stats.game_active = True
# Empty the list of aliens and bullets.
aliens.empty()
bullets.empty()
# Create a new fleet and center the ship.
create_fleet(ai_settings, screen, ship, aliens)
ship.center_ship()
def update_screen(ai_settings, screen, stats, sb, ship, aliens, bullets,
play_button):
"""Update images on the screen and flip to the new screen"""
# Redraw the screen through each pass through the loop.
screen.fill(ai_settings.bg_color)
# Redraw all bullets behind ship and aliens.
for bullet in bullets.sprites():
bullet.draw_bullet()
ship.blitme()
aliens.draw(screen)
# Draw the score information.
sb.show_score()
# Draw the play button if the game is inactive.
if not stats.game_active:
play_button.draw_button()
# Make the most recently drawn screen visible.
pygame.display.flip()
def update_bullets(ai_settings, screen, stats, sb, ship, aliens, bullets):
"""Update the position bullets and get rid of old bullets."""
# Update bullet positions.
bullets.update()
# Get rid of bullets that have disapeared.
for bullet in bullets.copy():
if bullet.rect.bottom <= 0:
bullets.remove(bullet)
check_bullet_alien_collisions(ai_settings, screen, stats, sb, ship,
aliens, bullets)
def check_bullet_alien_collisions(ai_settings, screen, stats, sb, ship,
aliens, bullets):
"""Respond to bullet-alien collisions."""
# Remove any bullets and aliens that have collided.
collisions = pygame.sprite.groupcollide(bullets, aliens, True, True)
if collisions:
stats.score += ai_settings.alien_points
sb.prep_score()
if len(aliens) == 0:
# Destroy existing bullets, speed up game, and create new fleet.
bullets.empty()
ai_settings.increase_speed()
create_fleet(ai_settings, screen, ship, aliens)
def get_number_aliens_x(ai_settings, alien_width):
"""Determine the number of aliens that fit in a row."""
available_space_x = ai_settings.screen_width - 2 * alien_width
number_aliens_x = int(available_space_x / (2 * alien_width))
return number_aliens_x
def get_number_rows(ai_settings, ship_height, alien_height):
"""Determine the number of rows of aliens that fit across the screen."""
available_space_y = (ai_settings.screen_height -
(3 * alien_height) - ship_height)
number_rows = int(available_space_y / (2 * alien_height))
return number_rows
def create_alien(ai_settings, screen, aliens, alien_number, row_number):
"""Create an alien and place it in the row."""
# create an alien and place it in the row.
alien = Alien(ai_settings, screen)
alien_width = alien.rect.width
alien.x = alien_width + 2 * alien_width * alien_number
alien.rect.x = alien.x
alien.rect.y = alien.rect.height + 2 * alien.rect.height * row_number
aliens.add(alien)
def create_fleet(ai_settings, screen, ship, aliens):
"""Create full fleet of aliens."""
# Create an alien and find the number of aliens in a row.
alien = Alien(ai_settings, screen)
number_aliens_x = get_number_aliens_x(ai_settings, alien.rect.width)
number_rows = get_number_rows(ai_settings, ship.rect.height,
alien.rect.height)
# Create the fleet of aliens.
for row_number in range(number_rows):
for alien_number in range(number_aliens_x):
create_alien(ai_settings, screen, aliens, alien_number,
row_number)
def check_fleet_edges(ai_settings, aliens):
"""Respond appropriatly if any aliens have reached an edge."""
for alien in aliens.sprites():
if alien.check_edges():
change_fleet_direction(ai_settings, aliens)
break
def change_fleet_direction(ai_settings, aliens):
"""Drop the entire fleet and change the fleet's direction."""
for alien in aliens.sprites():
alien.rect.y += ai_settings.fleet_drop_speed
ai_settings.fleet_direction *= -1
def ship_hit(ai_settings, stats, screen, ship, aliens, bullets):
"""Respond to ship being hit by alien."""
if stats.ships_left > 0:
# Decrement ships_left.
stats.ships_left -= 1
# Empty the list of aliens and bullets.
aliens.empty()
bullets.empty()
# Create a new fleet and center the ship.
create_fleet(ai_settings, screen, ship, aliens)
ship.center_ship()
# Pause
sleep(0.5)
else:
stats.game_active = False
pygame.mouse.set_visible(True)
def check_aliens_bottom(ai_settings, stats, screen, ship, aliens, bullets):
"""Check if any aliens have reached the bottom of the screen."""
screen_rect = screen.get_rect()
for alien in aliens.sprites():
if alien.rect.bottom >= screen_rect.bottom:
# Treat this the same as if the ship got hit.
# Treat this the same as if the ship got hit.
ship_hit(ai_settings, stats, screen, ship, aliens, bullets)
break
def update_aliens(ai_settings, stats, screen, ship, aliens, bullets):
"""
Check if the fleet is at an edge,
and then update the position of all the aliens in the fleet.
"""
check_fleet_edges(ai_settings, aliens)
aliens.update()
# Look for alien-ship collisions.
if pygame.sprite.spritecollideany(ship, aliens):
ship_hit(ai_settings, stats, screen, ship, aliens, bullets)
# Look for aliens hitting the bottom of the screen.
check_aliens_bottom(ai_settings, stats, screen, ship, aliens, bullets)
class Settings():
"""A class to store all settings for Alien Invasion."""
def __init__(self):
"""Initialize the game's static settings."""
# Screen Settings
self.screen_width = 1200
self.screen_height = 600
self.bg_color = (230, 230, 230)
# Ship Settings
self.ship_limit = 3
# Bullet Settings
self.bullet_width = 3
self.bullet_height = 15
self.bullet_color = 60, 60, 60
self.bullets_allowed = 3
# Alien settings
self.fleet_drop_speed = 10
# How quickly the game speeds up
self.speedup_scale = 1.1
# fleet_direction of 1 represents right; -1 represents left.
self.fleet_direction = 1
self.initialize_dynamic_settings()
def initialize_dynamic_settings(self):
"""Initialize settings that change throuhout the game."""
self.ship_speed_factor = 1.5
self.bullet_speed_factor = 3
self.alien_speed_factor = 1
# Fleet_direction of 1 represents right; -1 represents left.
self.fleet_direction = 1
# Scoring
self.alien_points = 50
def increase_speed(self):
"""Increase speed settings."""
self.ship_speed_factor *= self.speedup_scale
self.bullet_speed_factor *= self.speedup_scale
self.alien_speed_factor *= self.speedup_scale
class GameStats():
"""Track statistics for Alien Invasion."""
def __init__(self, ai_settings):
"""Initialize statistics."""
self.ai_settings = ai_settings
self.reset_stats()
# Start the game in an inactive state.
self.game_active = False
# High score should never be reset.
self.high_score = 0
def reset_stats(self):
"""Initialize statistics that can change during the game."""
self.ships_left = self.ai_settings.ship_limit
self.score = 0
class Button():
def __init__(self, ai_settings, screen, msg):
"""Initialize button attributes."""
self.screen = screen
self.screen_rect = screen.get_rect()
# Set the dimensions and properties of the button.
self.width, self.height = 200, 50
self.button_color = (0, 255, 0)
self.text_color = (255, 255, 255)
self.font = pygame.font.SysFont(None, 48)
# Build the button's rect object and center it.
self.rect = pygame.Rect(0, 0, self.width, self.height)
self.rect.center = self.screen_rect.center
# The button message needs to be prepped only once.
self.prep_msg(msg)
def prep_msg(self, msg):
"""Turn msg into a rendered image and center text on the button."""
self.msg_image = self.font.render(msg, True, self.text_color,
self.button_color)
self.msg_image_rect = self.msg_image.get_rect()
self.msg_image_rect.center = self.rect.center
def draw_button(self):
# Draw blank button then draw message.
self.screen.fill(self.button_color, self.rect)
self.screen.blit(self.msg_image, self.msg_image_rect)
import pygame
from pygame.sprite import Sprite
class Alien(Sprite):
""" A class to represent a single alien in the fleet."""
def __init__(self, ai_settings, screen):
"""Initialize the alien and set starting position."""
super(Alien, self).__init__()
self.screen = screen
self.ai_settings = ai_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 aliens exact position
self.x = float(self.rect.x)
def blitme(self):
"""Draw the alien in its current location."""
self.screen.blit(self.image, self.rect)
def check_edges(self):
"""Return True if the alien is at the edge of the screen."""
screen_rect = self.screen.get_rect()
if self.rect.right >= screen_rect.right:
return True
elif self.rect.left <= 0:
return True
def update(self):
"""Move the alien right or left."""
self.x += (self.ai_settings.alien_speed_factor *
self.ai_settings.fleet_direction)
self.rect.x = self.x
class Button():
def __init__(self, ai_settings, screen, msg):
"""Initialize button attributes."""
self.screen = screen
self.screen_rect = screen.get_rect()
# Set the dimensions and properties of the button.
self.width, self.height = 200, 50
self.button_color = (0, 255, 0)
self.text_color = (255, 255, 255)
self.font = pygame.font.SysFont(None, 48)
# Build the button's rect object and center it.
self.rect = pygame.Rect(0, 0, self.width, self.height)
self.rect.center = self.screen_rect.center
# The button message needs to be prepped only once.
self.prep_msg(msg)
def prep_msg(self, msg):
"""Turn msg into a rendered image and center text on the button."""
self.msg_image = self.font.render(msg, True, self.text_color,
self.button_color)
self.msg_image_rect = self.msg_image.get_rect()
self.msg_image_rect.center = self.rect.center
def draw_button(self):
# Draw blank button then draw message.
self.screen.fill(self.button_color, self.rect)
self.screen.blit(self.msg_image, self.msg_image_rect)
import pygame
from pygame.sprite import Sprite
class Alien(Sprite):
""" A class to represent a single alien in the fleet."""
def __init__(self, ai_settings, screen):
"""Initialize the alien and set starting position."""
super(Alien, self).__init__()
self.screen = screen
self.ai_settings = ai_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 aliens exact position
self.x = float(self.rect.x)
def blitme(self):
"""Draw the alien in its current location."""
self.screen.blit(self.image, self.rect)
def check_edges(self):
"""Return True if the alien is at the edge of the screen."""
screen_rect = self.screen.get_rect()
if self.rect.right >= screen_rect.right:
return True
elif self.rect.left <= 0:
return True
def update(self):
"""Move the alien right or left."""
self.x += (self.ai_settings.alien_speed_factor *
self.ai_settings.fleet_direction)
self.rect.x = self.x
import pygame
class Ship():
def __init__(self, ai_settings, screen):
"""Initialize the ship and set its starting position."""
self.screen = screen
self.ai_settings = ai_settings
# Load the ship image and get its rect.
self.image = pygame.image.load('images/ship.bmp')
self.rect = self.image.get_rect()
self.screen_rect = screen.get_rect()
# Start each new ship at the bottom of the screen.
self.rect.centerx = self.screen_rect.centerx
self.rect.bottom = self.screen_rect.bottom
# Store a decimal value for the ships center.
self.center = float(self.rect.centerx)
# Movement flag
self.moving_right = False
self.moving_left = False
def update(self):
"""Update the ships position based on the movement flags."""
# Update ships center value not the rect.
if self.moving_right and self.rect.right < self.screen_rect.right:
self.center += self.ai_settings.ship_speed_factor
if self.moving_left and self.rect.left > 0:
self.center -= self.ai_settings.ship_speed_factor
# Update rect object from self.center.
self.rect.centerx = self.center
def blitme(self):
"""Draw the ship at its current location."""
self.screen.blit(self.image, self.rect)
def center_ship(self):
"""Center the ship on the screen."""
self.center = self.screen_rect.centerx
导入pygame
船舶等级（）：
定义初始化（自我、ai设置、屏幕）：
“”“初始化船舶并设置其起始位置。”“”
self.screen=屏幕
self.ai_设置=ai_设置
#加载船舶图像并获取其rect。
self.image=pygame.image.load（'images/ship.bmp'）
self.rect=self.image.get_rect（）
self.screen\u rect=screen.get\u rect（）
#在屏幕底部启动每艘新船。
self.rect.centerx=self.screen\u rect.centerx
self.rect.bottom=self.screen\u rect.bottom
#存储船舶中心的十进制值。
self.center=float（self.rect.centerx）
#运动旗
self.moving_right=False
self.moving_left=False
def更新（自我）：
“”“根据移动标志更新船舶位置。”“”
#更新配送中心值而不是rect。
如果self.moving\u right和self.rect.right0：
self.center-=self.ai\u设置.发货速度\u系数
#从self.center更新rect对象。
self.rect.centerx=self.center
def blitme（自）：
“”“在当前位置绘制船舶。”“”
self.screen.blit（self.image，self.rect）
def中心装运（自）：
“”“将船放在屏幕中央。”“”
self.center=self.screen\u rect.centerx