import pygame
from random import randint, choice

screen_length = 700
screen_width = 500
# 模拟彩带飘落的类，掉落的词作为彩带
class Word_drop(pygame.sprite.Sprite):

    # 设置属性：包括字体、下落速度、彩带来源、彩带框的属性
    def __init__(self):
        pygame.sprite.Sprite.__init__(self)
        self.font = pygame.font.SysFont(name=‘幼圆‘, size=10, bold=True, italic=True)
        self.speed = randint(15, 30)
        self.word = self.getWord()
        self.image = self.font.render(self.word, True,
                                      (randint(0, 255), randint(0, 255), randint(0, 255)))
        self.image = pygame.transform.rotate(self.image, randint(87, 93))
        self.rect = self.image.get_rect()
        self.rect.topleft = (randint(0, screen_length), -20)

    # 获取掉落的词
    def getWord(self):
        length = randint(1, 8)
        word = ‘‘
        for i in range(length):
            word += choice(‘qwertyuiopasdfghjklzxcvbnm1234567890QWERTYUIOPASDFGHJKLZXCVBNM‘)
        return word

    # 设置彩带更新的条件
    def update(self, *args):
        self.rect = self.rect.move(0, self.speed)
        if self.rect.top > screen_length:
            self.kill()

# 实现"跑马灯"效果的函数
def word_translate(jx, ztw1, ztw2, screen_length, text):
    max_ztw = max(ztw1, ztw2)
    jx.x -= 5
    if jx.x < 0 - max_ztw:
        jx.x = (screen_length + 10)
    screen.blit(text, [jx.x, jx.y])

if __name__ == ‘__main__‘:

    # 初始化工作
    pygame.init()
    pygame.font.init()

    # 渲染字体，两行字
    a = pygame.font.SysFont(name=‘幼圆‘, size=50, bold=True, italic=True)

    word1 = "   中国"
    text1 = a.render(word1, True, (255, 0, 0), (0, 0, 0))

    word2 = "我超级爱你"
    text2 = a.render(word2, True, (255, 0, 0), (0, 0, 0))

    # "跑马场"字体框的属性
    _, _, ztw1, zth1 = text1.get_rect()
    jx1 = pygame.Rect(screen_length, (screen_width / 2 - zth1), ztw1, zth1)

    _, _, ztw2, zth2 = text2.get_rect()
    jx2 = pygame.Rect(screen_length, (screen_width / 2), ztw2, zth2)

    # 其他相关设置
    screen = pygame.display.set_mode((screen_length, screen_width))
    clock = pygame.time.Clock()
    wordGroup = pygame.sprite.Group()

    while True:

        clock.tick(30)
        screen.fill((0, 0, 0))

        # 设置退出的条件
        for event in pygame.event.get():
            if event.type == pygame.QUIT:
                pygame.quit()
                exit(0)

        # 彩带飘落
        word_object = Word_drop()
        wordGroup.add(word_object)
        wordGroup.update()
        wordGroup.draw(screen)

        # "跑马场"
        word_translate(jx1, ztw1, ztw2, screen_length, text1)
        word_translate(jx2, ztw1, ztw2, screen_length, text2)

        pygame.display.update()