在Python中使用街机库显示降雪

在本文中，我们将使用街机Python包显示降雪。 Arcade库是一个现代Python模块，广泛用于开发具有引人入胜的图形和声音的 2D 视频游戏。它是一个面向对象的库，可以像任何其他Python包一样安装。

循序渐进的方法：

• 本系列的第一步也是最重要的一步是在您的Python IDE 中导入Arcade库。还要导入random和math模块，因为在屏幕上的随机位置显示降雪。

Python3

# Import required modules
import random
import math
import arcade

• 指定输出屏幕的屏幕宽度、高度和标题的值。

蟒蛇3

# Adjust window attributes
Width = 800
Height = 600
Title = "SnowFall"

• 定义一个由__init__方法和一个将降雪重置到屏幕上方随机位置的函数组成的类snow_fall 。

蟒蛇3

class snow_fall:
    def __init__(self):
        self.x = 0
        self.y = 0
  
    def reset_snow(self):
  
        # Reset flake to random position above screen
        self.y = random.randrange(Height, Height + 100)
        self.x = random.randrange(Width)

• 现在，定义另一个类snowfall()和函数来随机定位降雪。

蟒蛇3

class snowfall(arcade.Window):
    def __init__(self, width, height, title):
        
        # Calls "__init__" of parent class 
        # (arcade.Window) to setup screen
        super().__init__(width, height, title)
  
    def start_snowfall(self):
        
        # Set up snowfall and initialize variables.
        self.snowfall_list = []
  
        for i in range(50):
              
            # Create snowfall instance
            snowfall = snow_fall()
  
            # Randomly position snowfall
            snowfall.x = random.randrange(Width)
            snowfall.y = random.randrange(Height + 200)
  
            # Set other variables for the snowfall
            snowfall.size = random.randrange(8)
            snowfall.speed = random.randrange(20, 40)
            snowfall.angle = random.uniform(math.pi, math.pi * 2)
  
            # Add snowflake to snowfall list
            self.snowfall_list.append(snowfall)

• 设置背景颜色。

蟒蛇3

# Set the background color
arcade.set_background_color(arcade.color.BLUE)

• 现在，定义用于动画降雪和显示每个降雪的当前位置的函数。

蟒蛇3

def on_draw(self):
  
        # This command is necessary before drawing
        arcade.start_render()
  
        # Draw the current position of each snowfall
        for snowfall in self.snowfall_list:
            arcade.draw_circle_filled(snowfall.x, snowfall.y,
                                      snowfall.size, arcade.color.WHITE)
  
    def on_update(self, delta_time):
          
        # Animate all the snowfall falling
        for snowfall in self.snowfall_list:
            snowfall.y -= snowfall.speed * delta_time
  
            # Check if snowfall has fallen below screen
            if snowfall.y < 0:
                snowfall.reset_snow()
  
            # Some math to make the snowfall move side to side
            snowfall.x += snowfall.speed * \
                math.cos(snowfall.angle) * delta_time
            snowfall.angle += 1 * delta_time

• 最后一步是创建一个街机对象并调用所需的方法。

蟒蛇3

# Driver Code
if __name__ == "__main__":
    screen = snowfall(800, 600, "Snow")
    screen.start_snowfall()
    arcade.run()

以下是基于上述方法的完整程序：

蟒蛇3

# Import required modules
import random
import math
import arcade
  
  
  
# Adjust window attributes
Width = 800
Height = 600
Title = "SnowFall"
  
  
  
class snow_fall:
    def __init__(self):
        self.x = 0
        self.y = 0
  
    def reset_snow(self):
          
        # Reset flake to random position above screen
        self.y = random.randrange(Height, Height + 100)
        self.x = random.randrange(Width)
  
  
  
class snowfall(arcade.Window):
    def __init__(self, width, height, title):
        
        # Calls "__init__" of parent class 
        # (arcade.Window) to setup screen
        super().__init__(width, height, title)
  
    def start_snowfall(self):
        
        # Set up snowfall and initialize variables.
        self.snowfall_list = []
  
        for i in range(50):
              
            # Create snowfall instance
            snowfall = snow_fall()
  
            # Randomly position snowfall
            snowfall.x = random.randrange(Width)
            snowfall.y = random.randrange(Height + 200)
  
            # Set other variables for the snowfall
            snowfall.size = random.randrange(8)
            snowfall.speed = random.randrange(20, 40)
            snowfall.angle = random.uniform(math.pi, math.pi * 2)
  
            # Add snowflake to snowfall list
            self.snowfall_list.append(snowfall)
  
        # Set the background color
        arcade.set_background_color(arcade.color.BLUE)
  
    def on_draw(self):
          
        # This command is necessary before drawing
        arcade.start_render()
  
        # Draw the current position of each snowfall
        for snowfall in self.snowfall_list:
            arcade.draw_circle_filled(snowfall.x, snowfall.y,
                                      snowfall.size, arcade.color.WHITE)
  
    def on_update(self, delta_time):
          
        # Animate all the snowfall falling
        for snowfall in self.snowfall_list:
            snowfall.y -= snowfall.speed * delta_time
  
            # Check if snowfall has fallen below screen
            if snowfall.y < 0:
                snowfall.reset_snow()
  
            # Some math to make the snowfall move side to side
            snowfall.x += snowfall.speed * \
                math.cos(snowfall.angle) * delta_time
            snowfall.angle += 1 * delta_time
  
  
  
# Driver Code
if __name__ == "__main__":
    screen = snowfall(800, 600, "Snow")
    screen.start_snowfall()
    arcade.run()

输出：