在Python中使用 Arcade 创建雷达扫描动画

雷达扫描用于显示雷达数据的单级扫描，它们的显示出现在主显示窗口中。借助Python的街机模块，可以执行雷达扫描动画。在开始之前，强烈建议修改街机库的概念。

要执行雷达扫描动画，请按照以下步骤操作：-

第 1 步：在您各自的 Ide 中导入街机和数学模块。

import arcade
import math

步骤 2：指定输出窗口的参数。

# Set up the constants
WIDTH = 800
_HEIGHT = 600
TITLE = "Radar Sweep"

第 3 步：这些常数控制有关雷达的细节。

CENTER_X = SCREEN_WIDTH // 2
CENTER_Y = SCREEN_HEIGHT // 2
RADIANS_PER_FRAME = 0.02
SWEEP_LENGTH = 250

第 4 步：定义一个 on_draw函数，在该函数下移动扫描的角度并使用 math 计算我们的雷达扫描的终点。最后画出雷达的轮廓。

def on_draw(_delta_time):
   # Move the angle of the sweep.
   on_draw.angle += RADIANS_PER_FRAME
   
   # Calculate the end point of our radar sweep. 
   x = SWEEP_LENGTH * math.sin(on_draw.angle) + CENTER_X
   y = SWEEP_LENGTH * math.cos(on_draw.angle) + CENTER_Y
   
   # Start the render. 
   arcade.start_render()
   
   # Draw the radar line
   arcade.draw_line(CENTER_X, CENTER_Y, x, y,
    arcade.color.OLIVE, 4)
   
   # Draw the outline of the radar
   arcade.draw_circle_outline(CENTER_X, CENTER_Y, 
   SWEEP_LENGTH, arcade.color.DARK_GREEN, 10)

# This is a function-specific variable i.e  
# we need to give them initial
# values.
on_draw.angle = 0  

第五步：定义主函数。

def main():

   # Open up our window
   arcade.open_window(SCREEN_WIDTH, SCREEN_HEIGHT,
    SCREEN_TITLE)
   arcade.set_background_color(arcade.color.BLACK)
   
   # Tell the computer to call the draw command at
   # the specified interval.
   arcade.schedule(on_draw, 1 / 80)
   
   # Run the program
   arcade.run()
   
   #  close the window.
   arcade.close_window()
  main()

雷达扫描看起来像这样——

完整的源代码：

Python3

import arcade
import math
  
# Set up the constants
SCREEN_WIDTH = 800
SCREEN_HEIGHT = 600
SCREEN_TITLE = "Radar Sweep Example"
  
# These constants control the particulars 
# about the radar
CENTER_X = SCREEN_WIDTH // 2
CENTER_Y = SCREEN_HEIGHT // 2
RADIANS_PER_FRAME = 0.02
SWEEP_LENGTH = 250
  
  
def on_draw(_delta_time):
  
    # Move the angle of the sweep.
    on_draw.angle += RADIANS_PER_FRAME
  
    # Calculate the end point of our radar sweep. Using math.
    x = SWEEP_LENGTH * math.sin(on_draw.angle) + CENTER_X
    y = SWEEP_LENGTH * math.cos(on_draw.angle) + CENTER_Y
  
    # Start the render.
    arcade.start_render()
  
    # Draw the radar line
    arcade.draw_line(CENTER_X, CENTER_Y, x, y, arcade.color.OLIVE, 4)
  
    # Draw the outline of the radar
    arcade.draw_circle_outline(CENTER_X, CENTER_Y, SWEEP_LENGTH,
                               arcade.color.DARK_GREEN, 10)
  
  
on_draw.angle = 0
  
  
def main():
  
    # Open up our window
    arcade.open_window(SCREEN_WIDTH, SCREEN_HEIGHT, SCREEN_TITLE)
    arcade.set_background_color(arcade.color.BLACK)
  
    # Tell the computer to call the draw command at the specified interval.
    arcade.schedule(on_draw, 1 / 80)
  
    # Run the program
    arcade.run()
  
    # close the window.
    arcade.close_window()
  
main()

输出：