您可以在第56行看到我的game_functions.py。它说“ stats.reset_stats”对吗？但是游戏开始时并未重置比分。怎么会发生？（代码很长，但是请耐心等待。）
我正在遵循《 Python Crash Course》这本书的第14章。我将其与源代码进行了比较。除了提交和之后的内容之外，我没有发现其他不同之处。
import sys
import pygame
from settings import Settings
from ship import Ship
import game_functions as gf
from pygame.sprite import Group
from game_stats import GameStats
from button import Button
from scoreboard import Scoreboard
def run_game():
#create the game
pygame.init()
ai_settings = Settings()
screen = pygame.display.set_mode(
(ai_settings.screen_width,ai_settings.screen_height))
pygame.display.set_caption("Alien Invasion")
#create a ship
ship = Ship(ai_settings, screen)
#create the bullets
bullets = Group()
#create the Aliens
aliens = Group()
#create alien Group
gf.create_fleet(ai_settings, screen,ship , aliens)
#Create a instance to store game statistics and create a scoreboard.
stats = GameStats(ai_settings)
sb = Scoreboard(ai_settings, screen, stats)
#Make the Play button.
play_button = Button(ai_settings, screen, "Play")
#Start the main loop for the game.
while True:
gf.check_events(ai_settings ,screen, stats,play_button,ship,aliens,
bullets)
if stats.game_activate == True:
ship.update()
bullets.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()
class Settings():
"""Store all the settings in Alien Invasion"""
def __init__(self):
"""Initialize the game's static settings"""
#Screen settings
self.screen_width = 850
self.screen_height = 570
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
self.fleet_direction = 1
#How quickly the alien value increase.
self.score_scale = 1.5
#How quickly the game speeds up
self.speedup_scale = 1.1
self.initialize_dynamic_settings()
def initialize_dynamic_settings(self):
"""Initialize settings that change throughout 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 and alien point values."""
self.ship_speed_factor *= self.speedup_scale
self.bullet_speed_factor *= self.speedup_scale
self.alien_speed_factor *= self.speedup_scale
self.alien_points = int(self.alien_points * self.score_scale)
import sys
import pygame
from bullet import Bullet
from alien import Alien
from time import sleep
def check_keydown_events(event ,stats,ai_settings ,screen, ship, bullets):
"""Respond to key presses."""
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()
elif event.key == pygame.K_p:
stats.game_activate = True
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 key presses 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,stats,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 a new game when the player clicks Play"""
button_clicked = play_button.rect.collidepoint(mouse_x,mouse_y)
if button_clicked and not stats.game_activate:
#Reset the game settings.
ai_settings.initialize_dynamic_settings()
#Hide the mouse cursor.
pygame.mouse.set_visible(False)
#Reset the game statistics
stats.reset_stats()
stats.game_activate = 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 the images on the screen, and flip to new screen"""
#Redraw the screen, 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 inactivate.
if not stats.game_activate:
play_button.draw_button()
#make the current surface visible
pygame.display.flip()
def update_bullets(ai_settings,screen,stats,sb,ship,aliens,bullets):
"""update the position of the bullet and delete invisible bullets"""
bullets.update()
#delete invisible bullets
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):
"""check bullet alien collisions"""
collisions = pygame.sprite.groupcollide(bullets,aliens, True , True)
if collisions:
for aliens in collisions.values():
stats.score += ai_settings.alien_points * len(aliens)
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 fire_bullet(ai_settings, screen, ship, bullets):
"""if it doesn't touch the limit ,shoot a bullet"""
#create a bullet and join it to group 'bullets'
if len(bullets) < ai_settings.bullets_allowed:
new_bullet = Bullet(ai_settings, screen, ship)
bullets.add(new_bullet)
def get_aliens_x(ai_settings, alien_width):
"""calculate how many aliens can be included in one line"""
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):
"""calculate how many lines can be included on 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 put it in the current line"""
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 alien group """
alien = Alien(ai_settings, screen)
number_aliens_x = get_aliens_x(ai_settings, alien.rect.width)
number_rows = get_number_rows(ai_settings, ship.rect.height,
alien.rect.height)
#create alien group
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):
"""if aliens touch edge then ... """
for alien in aliens.sprites():
if alien.check_edges():
change_fleet_direction(ai_settings, aliens)
break
def change_fleet_direction(ai_settings, aliens):
"""move the aliens down and change their 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 the ship that are hit"""
if stats.ships_left > 0:
#change ships_left by -1
stats.ships_left -= 1
else:
stats.game_activate = False
pygame.mouse.set_visible(True)
#clear Alien group and Bullet group
aliens.empty()
bullets.empty()
#create a new group of alien, and put the ship BOTTOM-MIDDLE.
create_fleet(ai_settings, screen, ship, aliens)
ship.center_ship()
#pause
sleep(0.5)
def check_aliens_bottom(ai_settings, stats, screen, ship, aliens, bullets):
"""check if any aliens touches the edge"""
screen_rect = screen.get_rect()
for alien in aliens.sprites():
if alien.rect.bottom > screen_rect.bottom:
#do as ship-alien collisions
ship_hit(ai_settings,stats,screen,ship,aliens,bullets)
break
def update_aliens(ai_settings,stats,screen,ship,aliens,bullets):
"""update the position of alien groups """
check_fleet_edges(ai_settings, aliens)
aliens.update()
#check alien-ship collisions
if pygame.sprite.spritecollideany(ship, aliens):
ship_hit(ai_settings,stats,screen,ship,aliens,bullets)
check_aliens_bottom(ai_settings, stats, screen, ship, aliens, bullets)
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 scoring information.
self.text_color = (30,30,30)
self.font = pygame.font.SysFont(None, 48)
#Prepare the inital score image.
self.prep_score()
def prep_score(self):
"""Turn the score into a rendered image."""
rounded_score = int(round(self.stats.score, -1))
score_str = "{:,}".format(rounded_score)
self.score_image = self.font.render(score_str,True, self.text_color,
self.ai_settings.bg_color)
#Display the score at the top right 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)
class GameStats():
"""Track statistics for Alien Invasion."""
def __init__(self, ai_settings):
"""Initialize statistics"""
self.ai_settings = ai_settings
self.reset_stats()
#Start game in an inactivate state
self.game_activate = False
def reset_stats(self):
"""initialize changeable statistics during the game"""
self.ships_left = self.ai_settings.ship_limit
self.score = 0