game_functions.py

import sys

import pygame
from alien import Alien
from bullet import Bullet


def check_keydown_events(event, ai_settings, screen, ship, bullets):
    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:
        if len(bullets) < ai_settings.bullets_allowed:
            new_bullet = Bullet(ai_settings, screen, ship)
            bullets.add(new_bullet)
    elif event.key == pygame.K_q:
        sys.exit()


def check_keyup_events(event, ship):
    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, ship, bullets):
    # respond to keypress and mouse
    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)


def update_screen(ai_settings, screen, ship, alien, bullets):
    screen.fill((ai_settings.bg_color))
    for bullet in bullets.sprites():
        bullet.draw_bullet()
    ship.blitme()
    alien.blitme()
    # Make the most recently drawn screen visible
    pygame.display.flip()


def update_bullets(bullets):
    bullets.update()
    for bullet in bullets.copy():
        if bullet.rect.bottom <= 0:
            bullets.remove(bullet)
    print(len(bullets))