Python Programming - Stars: Find a star image and display a series of neatly arranged stars on the screen

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Note: This question is an exercise question from the book Python Programming from Introduction to Practice

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1. Flowchart

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2. Procedure

2.1 Screen parameters

import pygame

class StarSettings:
    def __init__(self):
        # 屏幕设置
        self.screen_width = 1000
        self.screen_height = 600
        self.bg_color = (255, 255, 255)

2.2 Image parameter settings

import pygame
from pygame.sprite import Sprite

class StarImages(Sprite):
    def __init__(self, image_attr):

        super().__init__()  #继承Sprite类

        self.screen = image_attr.screen
        self.settings = image_attr.settings
        self.screen_rect = image_attr.screen.get_rect() #屏幕尺寸

        self.image = pygame.image.load("images/star.bmp")

        self.rect = self.image.get_rect()   #图片尺寸
        self.rect.x = self.rect.width   #初始位置
        self.rect.y = self.rect.height
        # self.rect.x = 0
        # self.rect.y = 0

        # self.x = float(self.rect.x)

2.3 Display some parameter settings

import sys
import pygame
from star_settings import StarSettings
from star_figure import StarImages

class StarMain:
    def __init__(self):
        pygame.init()
        self.settings = StarSettings()

        self.screen = pygame.display.set_mode((self.settings.screen_width, self.settings.screen_height))
        pygame.display.set_caption("Star Display")

        self.star_images = pygame.sprite.Group()

        self._create_images()

    def star_display(self):
        while True:
            self._check_events()
            self._update_screen()

    def _check_events(self):  # 辅助方法
        for event in pygame.event.get():
            if event.type == pygame.QUIT:
                sys.exit()

            if event.type == pygame.KEYDOWN:
                if event.key == pygame.K_q:
                    sys.exit()

    def _update_screen(self):
        #每次循环都重绘屏幕
        self.screen.fill(self.settings.bg_color)    #填充颜色
        self.star_images.draw(self.screen)
        # 让最近绘制的屏幕可见
        pygame.display.flip()

    def _create_images(self):
        my_image = StarImages(self)
        image_width, image_height = my_image.rect.size

        available_space_x = self.settings.screen_width - (2 * image_width)
        number_image_x = available_space_x // (2 * image_width)
        available_space_y = self.settings.screen_height - (2 * image_height)
        number_rows = available_space_y // (2 * image_height)

        for all_row in range(number_rows):
            for num_image in range(number_image_x):
                self._create_one_image(num_image, all_row)

    def _create_one_image(self, image_num, row_num):
        image_attr = StarImages(self)
        image_width, image_height = image_attr.rect.size
        image_attr.x = image_width + 2 * image_width * image_num
        image_attr.rect.x = image_attr.x
        image_attr.rect.y = image_attr.rect.height + 2 * image_attr.rect.height * row_num
        self.star_images.add(image_attr)

if __name__ == '__main__':
    star = StarMain()
    star.star_display()

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3. Appendix

3.1 Pictures

Download link:Image download

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4. Summary

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Mainly learn the application of pygame and display neatly arranged stars through the Sprite module. Display a star first, then loop through to create an array of stars.

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