更新 'game_functions.py'

game_functions.py

@@ -86,21 +86,176 @@ def check_play_button(ai_settings, screen, stats, sb, play_button, ship, aliens,
 
         # 创建一群新的外星人，并让飞船居中
         create_fleet(ai_settings, screen, ship, aliens)
+        ship.center_ship()
+
+def update_bullets(ai_settings, screen, stats, sb, ship, aliens, bullets):
+    """更新子弹的位置，并删除已消失的子弹"""
+    # 更新子弹的位置
+    bullets.update()
+
+    # 删除已消失的子弹
+    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):
+    """响应子弹和外星人的碰撞"""
+    # 删除发生碰撞的子弹和外星人
+    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:
+        # 如果整群外星人都被消灭，就提高一个等级
+        bullets.empty()
+        ai_settings.increase_speed()
+
+        # 提高等级
+        stats.level += 1
+        sb.prep_level()
+
+        create_fleet(ai_settings, screen, ship, aliens)
+
+def update_screen(ai_settings, screen, stats, sb, ship, aliens, bullets,
+                  play_button):
+    """更新屏幕上的图像，并切换到新屏幕"""
+    # 每次循环时都重绘屏幕
+    # 背景图片
+    bg_image = pygame.image.load('images/111.bmp')
+    screen.blit(bg_image, (0, 0))
+    # 在飞船和外星人后面重绘所有子弹
+    for bullet in bullets.sprites():
+        bullet.draw_bullet()
+    ship.blitme()
+    aliens.draw(screen)
+
+    # 显示得分
+    sb.show_score()
+
+    # 如果游戏处于非活动状态，就绘制Play按钮
+    if not stats.game_active:
+        play_button.draw_button()
+
+    # 让最近绘制的屏幕可见
+    pygame.display.flip()
+
+
+def get_number_aliens_x(ai_settings, alien_width):
+    """计算每行可容纳多少个外星人"""
+    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):
+    """计算屏幕可容纳多少行外星人"""
+    available_space_y = (ai_settings.screen_height -
+                         (3 * alien_height) - ship_height)
+    number_rows = int(available_space_y / (3 * alien_height))
+    return number_rows
+
+
+def create_alien(ai_settings, screen, aliens, alien_number, row_number):
+    """创建一个外星人并将其放在当前行"""
+    alien = Alien(ai_settings, screen)
+    alien_width = alien.rect.width
+    alien.x = alien_width + 2 * alien_width * alien_number
+    alien.rect.y = alien.rect.height + 2 * alien.rect.height * row_number
+    alien.rect.x = alien.x
+    aliens.add(alien)
+
+
+def create_fleet(ai_settings, screen, ship, aliens):
+    """创建外星人群"""
+    # 创建一个外星人，并计算每行可容纳多少个外星人
+    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)
+
+    # 创建外星人群
+    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):
+    """有外星人到达边缘时采取相应的措施"""
+    for alien in aliens.sprites():
+        if alien.check_edges():
+            change_fleet_direction(ai_settings, aliens)
+            break
+
+
+def change_fleet_direction(ai_settings, aliens):
+    """将整群外星人下移，并改变它们的方向"""
+    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, sb, ship, aliens, bullets):
+    """响应被外星人撞到的飞船"""
+    if stats.ships_left > 0:
+        # 将ships_left减1
+        stats.ships_left -= 1
+
+        # 更新记分牌
         sb.prep_ships()
 
         # 清空外星人列表和子弹列表
         aliens.empty()
         bullets.empty()
 
-        # 清空外星人列表和子弹列表
-        aliens.empty()
-        bullets.empty()
-
-        # 创建一群新的外星人，并让飞船居中
+        # 创建一群新的外星人，并将飞船放到屏幕底端中央
         create_fleet(ai_settings, screen, ship, aliens)
         ship.center_ship()
 
-def update_bullets(ai_settings, screen, stats, sb, ship, aliens, bullets):
-    """更新子弹的位置，并删除已消失的子弹"""
-    # 更新子弹的位置
-    bullets.update()
+        # 暂停
+        sleep(3)
+
+    else:
+        stats.game_active = False
+        pygame.mouse.set_visible(True)
+
+
+def check_aliens_bottom(ai_settings, stats, screen, sb, ship, aliens, bullets):
+    """检查是否有外星人到达了屏幕底端"""
+    screen_rect = screen.get_rect()
+    for alien in aliens.sprites():
+        if alien.rect.bottom >= screen_rect.bottom:
+            # 像飞船被撞到一样进行处理
+            ship_hit(ai_settings, stats, screen, sb, ship, aliens, bullets)
+            break
+
+
+def check_high_score(stats, sb):
+    """检查是否诞生了新的最高得分"""
+    if stats.score > stats.high_score:
+        stats.high_score = stats.score
+        sb.prep_high_score()
+
+
+def update_aliens(ai_settings, stats, screen, sb, ship, aliens, bullets):
+    """
+    检查是否有外星人位于屏幕边缘，并更新整群外星人的位置
+    """
+    check_fleet_edges(ai_settings, aliens)
+    aliens.update()
+
+    # 检测外星人和飞船之间的碰撞
+    if pygame.sprite.spritecollideany(ship, aliens):
+        ship_hit(ai_settings, stats, screen, sb, ship, aliens, bullets)
+
+    # 检查是否有外星人到达屏幕底端
+    check_aliens_bottom(ai_settings, stats, screen, sb, ship, aliens, bullets)