Python Crash Course Game 显示未正确显示图像

Question

我一直在尝试解决这个问题，即所有图像都完全混乱并且无法正常显示。

它不会弹出任何错误，因此很难追溯原因：Here is a more detailed image of the issue

代码如下：

主要代码（alien_invasion.py）：

import sys
import game_functions as gf
import pygame
from settings import Settings
from ship import Ship
from pygame.sprite import Group
from alien import Alien
from game_stats import GameStats
from button import Button

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")

    play_button = Button(ai_settings, screen, "Play")

    stats = GameStats(ai_settings)
    alien = Alien(ai_settings, screen)

    screen.fill(ai_settings.bg_color)
    # Make a ship.
    ship = Ship(ai_settings, screen)
    aliens = Group()
    bullets = Group()

    # Background color
    bg_color = (230, 230, 230)
    gf.create_fleet(ai_settings, screen, aliens, ship)


    while True:

        gf.check_events(ai_settings, screen, ship, bullets, stats, play_button)
        if stats.game_active:
            ship.update(ai_settings)
            gf.update_aliens(ai_settings, aliens, ship, stats, screen, bullets)
            gf.update_bullets(bullets, aliens, ai_settings, screen, ship)

        gf.update_screen(ai_settings, bullets, screen, ship, aliens, stats, play_button)

        if not stats.game_active:
            play_button.draw_button()

    screen.fill(ai_settings.bg_color)

    ship.blitme(screen)
    pygame.display.flip()




run_game()

外星人代码（alien.py）：

import pygame
from pygame.sprite import Sprite

class Alien(Sprite):

    def __init__(self, ai_settings, screen):
        super(Alien, self).__init__()

        self.screen = screen
        self.ai_settings = ai_settings
        self.image = pygame.image.load(r'C:\Users\user\Desktop\alien invasion\alien.bmp')
        #Load the alien image and set its rect attribute
        self.rect = self.image.get_rect()
        #Start each new alienn 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 blitme(self):
        #Draw the alien at its current location
        self.screen.blit(self.image, self.rect)

    def update(self):
        self.x += (self.ai_settings.alien_speed_factor * self.ai_settings.fleet_direction)
        self.rect.x = self.x

    def check_edges(self):
        screen_rect = self.screen.get_rect()
        if self.rect.right >= screen_rect.right:
            return True
        elif self.rect.left <= 0:
            return True

项目符号代码（bullet.py）：

import pygame
from pygame.sprite import Sprite

class Bullet(Sprite):

    def __init__(self, ai_settings, screen, ship):
        super().__init__()
        self.screen = screen
        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
        self.y = float(self.rect.y)
        self.color = ai_settings.bullet_color
        self.ship_speed_factor = ai_settings.bullet_speed_factor

    def update(self):
        self.y -= self.ship_speed_factor
        self.rect.y = self.y


    def draw_bullet(self):
        pygame.draw.rect(self.screen, self.color, self.rect)

按钮代码（button.py）：

import pygame.font

class Button():
    def __init__(self, ai_settings, screen, msg):
        self.screen = screen
        self.screen_rect = screen.get_rect()
        self.width, self.height = 200, 50
        self.button_color = (0, 250, 0)
        self.text_color = (255, 255, 255)
        self.font = pygame.font.SysFont(None, 48)
        self.rect = pygame.Rect(0, 0, self.width, self.height)
        self.rect.center = (self.screen_rect.center)
        self.prep_msg(msg)

    def prep_msg(self, msg):
        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):
        self.screen.fill(self.button_color, self.rect)
        self.screen.blit(self.msg_image, self.msg_image_rect)

游戏功能代码（game_functions.py）：

import sys
import pygame
from bullet import Bullet
from alien import Alien
from time import sleep

def check_events(ai_settings, screen, ship, bullets, stats, play_button):

    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            sys.exit()

        elif event.type == pygame.MOUSEBUTTONDOWN:
            mouse_x, mouse_y = pygame.mouse.get_pos()
            check_play_button(stats, play_button, mouse_x, mouse_y)

        elif event.type == pygame.KEYDOWN:
            check_keydown_events(event,ship, ai_settings, screen, bullets)

        elif event.type == pygame.KEYUP:
            check_keyup_events(event, ship)


def update_screen(ai_settings, bullets, screen, ship, aliens, stats, play_button):

    for bullet in bullets.sprites():
        bullet.draw_bullet()



    aliens.draw(screen)
    ship.blitme(screen)
    pygame.display.flip()

def check_keydown_events(event, ship, ai_settings, screen, 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:
        fire_bullet(ai_settings, screen, ship, bullets)
    elif event.key == pygame.K_q:
        sys.exit()

def fire_bullet(ai_settings, screen, ship, bullets):
        if len(bullets) < ai_settings.bullets_allowed:
            new_bullet =  Bullet(ai_settings, screen, ship)
            bullets.add(new_bullet)


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 update_bullets(bullets, aliens, ai_settings, screen, ship):
    bullets.update()
    collisions = pygame.sprite.groupcollide(bullets, aliens, True, True)
    if len(aliens) == 0:
        bullets.empty()
        create_fleet(ai_settings, screen, aliens, ship)
    for bullet in bullets.copy():
        if bullet.rect.bottom <= 0:
            bullets.remove(bullet)


def create_fleet(ai_settings, screen, aliens, ship):
    alien = Alien(ai_settings, screen)
    alien_width = alien.rect.width
    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)
    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 get_number_aliens_x(ai_settings, alien_width):
    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 create_alien(ai_settings, screen, aliens, alien_number, row_number):
    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 get_number_rows(ai_settings, ship_height, alien_height):
    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 update_aliens(ai_settings, aliens, ship, stats, screen, bullets):
    check_fleet_edges(ai_settings, aliens)
    aliens.update()
    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)

def check_fleet_edges(ai_settings, aliens):
    for alien in aliens.sprites():
        if alien.check_edges():
            change_fleet_direction(ai_settings, aliens)
            break

def change_fleet_direction(ai_settings, aliens):
    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):
    if stats.ships_left > 0:
        stats.ships_left -= 1
        aliens.empty()
        bullets.empty()
        create_fleet(ai_settings, screen, aliens, ship)
        ship.center_ship
        sleep(0.5)
    else:
        stats.game_active = False


def check_aliens_bottom(ai_settings, stats, screen, ship, aliens, bullets):
    screen_rect = screen.get_rect()
    for alien in aliens.sprites():
        if alien.rect.bottom >= screen_rect.bottom:
            ship_hit(ai_settings, stats, screen, ship, aliens, bullets)
            break

def check_play_button(stats, play_button, mouse_x, mouse_y):
    if play_button.rect.collidepoint(mouse_x, mouse_y):
        stats.game_active = True

游戏统计数据 (game_stats.py)：

class GameStats():
    def __init__(self, ai_settings):
        self.ai_settings = ai_settings
        self.reset_stats()
        self.game_active = True

    def reset_stats(self):
        self.ships_left = self.ai_settings.ship_limit

设置代码（settings.py）：

class Settings():
    def __init__(self):
        self.screen_width = 1200
        self.screen_height = 800
        self.bg_color = (230, 230, 230)
        self.ship_speed_factor = 10
        self.ship_limit = 3

        self.bullet_speed_factor = 3
        self.bullet_width = 3
        self.bullet_height = 12
        self.bullet_color = (60, 60, 60)
        self.bullets_allowed = 3

        self.alien_speed_factor = 1
        self.fleet_drop_speed = 10
        self.fleet_x_margin = 70
        self.fleet_y_margin = 70
        self.fleet_direction = -1

发货代码（ship.py）：

import pygame
from pygame.sprite import Sprite
class Ship(Sprite):
    def __init__(self, ai_settings, screen):
        super(Ship, self).__init__()
        self.screen = screen
        self.ai_settings = ai_settings
        self.image = pygame.image.load(r'C:\Users\user\Desktop\alien invasion\ship.bmp')
        self.rect = self.image.get_rect()
        self.screen_rect = screen.get_rect()
        self.rect.centerx = self.screen_rect.centerx
        self.rect.bottom = self.screen_rect.bottom
        self.moving_right = False
        self.moving_left = False
        self.center = float(self.rect.centerx)
        self.center += self.ai_settings.ship_speed_factor



    def update(self, ai_settings):
        self.ai_settings = ai_settings
        if self.moving_right and self.rect.right < self.screen_rect.right:
            self.rect.centerx += 1
            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
            self.rect.centerx -= 1


    def blitme(self, screen):
        self.screen.blit(self.image, self.rect)

    def center_ship(self):
        self.center = self.screen_rect.centerx

任何帮助将不胜感激！

Answer 1

需要简单的改变。在绘制外星人之前清除屏幕。

while True:

    screen.fill(ai_settings.bg_color)   #  <<<<<<<  clear screen first
    gf.check_events(ai_settings, screen, ship, bullets, stats, play_button)
    if stats.game_active:
        ship.update(ai_settings)
        gf.update_aliens(ai_settings, aliens, ship, stats, screen, bullets)
        gf.update_bullets(bullets, aliens, ai_settings, screen, ship)

    gf.update_screen(ai_settings, bullets, screen, ship, aliens, stats, play_button)

    if not stats.game_active:
        play_button.draw_button()