python如何实现飞船大战

import pygame
from pygame.sprite import Sprite

class Ship(Sprite):

  def __init__(self, ai_settings, screen):
    """Initialize the ship, and set its starting position."""
    super(Ship, self).__init__()
    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 center of the screen.
    self.rect.centerx = self.screen_rect.centerx
    self.rect.bottom = self.screen_rect.bottom
    
    # Store a decimal value for the ship's center.
    self.center = float(self.rect.centerx)
    
    # Movement flags.
    self.moving_right = False
    self.moving_left = False
    
  def center_ship(self):
    """Center the ship on the screen."""
    self.center = self.screen_rect.centerx
    
  def update(self):
    """Update the ship's position, based on movement flags."""
    # Update the ship's 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)

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 = 800
    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
    # How quickly the alien point values increase.
    self.score_scale = 1.5
  
    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
    
    # Scoring.
    self.alien_points = 50
  
    # fleet_direction of 1 represents right, -1 represents left.
    self.fleet_direction = 1
    
  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 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, at the ship's current position."""
    super(Bullet, self).__init__()
    self.screen = screen

    # Create bullet rect at (0, 0), 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 a decimal value for the bullet's position.
    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 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, sb, 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, sb, play_button,
        ship, aliens, bullets, mouse_x, mouse_y)
      
def check_play_button(ai_settings, screen, stats, sb, 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_active:
    # 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_active = True
    
    # Reset the scoreboard images.
    sb.prep_score()
    sb.prep_high_score()
    sb.prep_level()
    sb.prep_ships()
    
    # 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 fire_bullet(ai_settings, screen, ship, bullets):
  """Fire a bullet, if limit not reached yet."""
  # Create a new bullet, add to bullets group.
  if len(bullets) < ai_settings.bullets_allowed:
    new_bullet = Bullet(ai_settings, screen, ship)
    bullets.add(new_bullet)

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, 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 position of bullets, and get rid of old bullets."""
  # Update bullet positions.
  bullets.update()

  # Get rid of bullets that have disappeared.
  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_high_score(stats, sb):
  """Check to see if there's a new high score."""
  if stats.score > stats.high_score:
    stats.high_score = stats.score
    sb.prep_high_score()
      
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:
    for aliens in collisions.values():
      stats.score += ai_settings.alien_points * len(aliens)
      sb.prep_score()
    check_high_score(stats, sb)
  
  if len(aliens) == 0:
    # If the entire fleet is destroyed, start a new level.
    bullets.empty()
    ai_settings.increase_speed()
    
    # Increase level.
    stats.level += 1
    sb.prep_level()
    
    create_fleet(ai_settings, screen, ship, aliens)
  
def check_fleet_edges(ai_settings, aliens):
  """Respond appropriately 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, screen, stats, sb, ship, aliens, bullets):
  """Respond to ship being hit by alien."""
  if stats.ships_left > 0:
    # Decrement ships_left.
    stats.ships_left -= 1
    
    # Update scoreboard.
    sb.prep_ships()
    
  else:
    stats.game_active = False
    pygame.mouse.set_visible(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()
  
  # Pause.
  sleep(0.5)
  
def check_aliens_bottom(ai_settings, screen, stats, sb, 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.
      ship_hit(ai_settings, screen, stats, sb, ship, aliens, bullets)
      break
      
def update_aliens(ai_settings, screen, stats, sb, ship, aliens, bullets):
  """
  Check if the fleet is at an edge,
   then update the postions of all 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, screen, stats, sb, ship, aliens, bullets)

  # Look for aliens hitting the bottom of the screen.
  check_aliens_bottom(ai_settings, screen, stats, sb, ship, aliens, bullets)
      
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 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 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 a full fleet of aliens."""
  # Create an alien, and find 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)

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
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 a scoreboard.
  stats = GameStats(ai_settings)
  sb = Scoreboard(ai_settings, screen, stats)
  
  # Set the background color.
  bg_color = (230, 230, 230)
  
  # 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, sb, 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, screen, stats, sb, 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 Alien(Sprite):
  """A class to represent a single alien in the fleet."""

  def __init__(self, ai_settings, screen):
    """Initialize the alien, and set its 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 alien's exact position.
    self.x = float(self.rect.x)
    
  def check_edges(self):
    """Return True if alien is at edge of 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

  def blitme(self):
    """Draw the alien at its current location."""
    self.screen.blit(self.image, self.rect)

import pygame.font

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 only needs to be prepped 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)

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 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
    self.level = 1

import pygame.font
from pygame.sprite import Group

from ship import Ship

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 initial score images.
    self.prep_score()
    self.prep_high_score()
    self.prep_level()
    self.prep_ships()

  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 prep_high_score(self):
    """Turn the high score into a rendered image."""
    high_score = int(round(self.stats.high_score, -1))
    high_score_str = "{:,}".format(high_score)
    self.high_score_image = self.font.render(high_score_str, True,
      self.text_color, self.ai_settings.bg_color)
        
    # Center the high score at the top of the screen.
    self.high_score_rect = self.high_score_image.get_rect()
    self.high_score_rect.centerx = self.screen_rect.centerx
    self.high_score_rect.top = self.score_rect.top
    
  def prep_level(self):
    """Turn the level into a rendered image."""
    self.level_image = self.font.render(str(self.stats.level), True,
        self.text_color, self.ai_settings.bg_color)
    
    # Position the level below the score.
    self.level_rect = self.level_image.get_rect()
    self.level_rect.right = self.score_rect.right
    self.level_rect.top = self.score_rect.bottom + 10
    
  def prep_ships(self):
    """Show how many ships are left."""
    self.ships = Group()
    for ship_number in range(self.stats.ships_left):
      ship = Ship(self.ai_settings, self.screen)
      ship.rect.x = 10 + ship_number * ship.rect.width
      ship.rect.y = 10
      self.ships.add(ship)
    
  def show_score(self):
    """Draw score to the screen."""
    self.screen.blit(self.score_image, self.score_rect)
    self.screen.blit(self.high_score_image, self.high_score_rect)
    self.screen.blit(self.level_image, self.level_rect)
    # Draw ships.
    self.ships.draw(self.screen)