【Python】Python编程从入门到实践课后题 12-3

12-3火箭：编写一个游戏， 开始时屏幕中央有一个火箭， 而玩家可使用四个方向键上下左右移动火箭。 请务必确保火箭不会移到屏幕外面 。

费了老劲把它改成这样了，为了把它放到一个文件里，示例里的东西都挪到一起了，纪念下

import sys

import pygame

class Rocket(): 
    def __init__(self,screen):
        #初始化飞船并设置其初始位置
        self.screen = screen

        #加载飞船图像并获取其外接矩形
        self.image = pygame.image.load(images/rocket.jpg)
        self.rect = self.image.get_rect()
        self.screen_rect = screen.get_rect()

        #将图片放在屏幕中央
        self.rect.centerx = self.screen_rect.width/2
        self.rect.bottom = self.screen_rect.height/2 + self.image.get_height()/2

        #移动标志
        self.moving_right = False
        self.moving_left = False
        self.moving_up = False
        self.moving_down = False
    def update(self):
        """根据移动标志调整飞船的位置"""
        if self.moving_right and self.rect.right < self.screen_rect.right + 20:
            self.rect.centerx += 1

        if self.moving_left and self.rect.left > 0-20:
            self.rect.centerx -= 1

        if self.moving_up and self.rect.top > 0-10:
            self.rect.bottom -= 1

        if self.moving_down and self.rect.bottom < self.screen_rect.bottom + 10:
            self.rect.bottom += 1

    def blitme(self):
        #在指定位置绘制飞船
        self.screen.blit(self.image, self.rect)

def check_keydown_events(event, rocket):
    if event.key == pygame.K_RIGHT:
        #向右移动飞船
        # ship.rect.centerx  += 1
        rocket.moving_right = True
    if event.key == pygame.K_LEFT:
        rocket.moving_left = True
    if event.key == pygame.K_UP:
        rocket.moving_up = True
    if event.key == pygame.K_DOWN:
        rocket.moving_down = True

def check_keyup_events(event, rocket):
    if event.key == pygame.K_RIGHT:
        rocket.moving_right = False
    elif event.key == pygame.K_LEFT:
        rocket.moving_left = False
    elif event.key == pygame.K_UP:
        rocket.moving_up = False
    elif event.key == pygame.K_DOWN:
        rocket.moving_down = False


def check_events(rocket):
    #响应按键和鼠标事件
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            sys.exit()
        elif event.type == pygame.KEYDOWN:
            check_keydown_events(event, rocket)
        elif event.type == pygame.KEYUP:
            check_keyup_events(event, rocket)
            

def update_screen(screen, rocket):
    """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
    # screen.fill(ai_settings.bg_color)
    rocket.blitme()

    #让最近绘制的屏幕可见
    pygame.display.flip()


def run_game():
    #初始化游戏并创建一个屏幕对象
    pygame.init()
    screen = pygame.display.set_mode((1200, 800))
    pygame.display.set_caption("Rocket")

    #设置背景色
    bg_color = (252, 252, 252)

    #创建一艘飞船
    rocket = Rocket(screen)

    #开始游戏的主循环
    while True:

        #监视键盘和鼠标事件
        # for event in pygame.event.get():
        #     if event.type == pygame.QUIT:
        #         sys.exit()
        # gf.check_events()
        check_events(rocket)

        #每次循环时都重绘屏幕
        screen.fill(bg_color)
        # screen.fill(ai_settings.bg_color)
        rocket.blitme()
        # #让最近绘制的屏幕可见
        # pygame.display.flip()

        rocket.update()
        update_screen(screen, rocket)


run_game()