python外星人入侵游戏

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