629-1830837-动画效果.sy.md

show	version	enable_checker
step	1.0	true

opencv

回忆

• 上次研究了写字效果
• 感觉可以做一个打字练习器
• 下次玩点什么呢？🤔

半径动画

import numpy as np                                                            
import cv2 
import time
width = height = 300 
x = y = 150 
r = 0 
while cv2.waitKey(1) == -1: 
    r = r + 1 
    img = np.ones((width, height, 3),np.uint8) * 255 
    cv2.circle(img, (x,y), r ,(255,0,0),-1)
    cv2.imshow("img",img)
    time.sleep(1/30)
cv2.destroyAllWindows()

• 半径从零到大

• 可以把具体参数输出出来吗？

尝试输出参数

import numpy as np        
import cv2             
import time            
width = height = 300   
x = y = 150            
r = 20                 
while cv2.waitKey(1) == -1: 
    img = np.ones((width, height, 3),np.uint8) * 255 
    y = y + 1          
    cv2.putText(img,"y="+str(y),(30,80),cv2.FONT_HERSHEY_TRIPLEX,2,(0,0,255),5)
    print("y=========",y)
    cv2.circle(img, (x,y), r ,(0,0,0),-1)
    cv2.imshow("img",img)
    time.sleep(1/30)   
cv2.destroyAllWindows()

• 圆心下移

• 并输出了参数
  • 画面
  • 控制台后台

大小缩放效果

import numpy as np 
import cv2         
import time        
width = height = 300
x = y = 150        
r = 0              
isBigger = True    
                   
while cv2.waitKey(1) == -1:
    if r == 100:   
        isBigger = False
    if r == 10:    
        isBigger = True
    if isBigger == True:
        r = r + 1  
    else:          
        r = r - 1  
    img = np.ones((width, height, 3),np.uint8) * 255
    cv2.circle(img, (x,y), r ,(0,0,255),-1)
    cv2.imshow("img",img)
    time.sleep(1/100)                                                          
cv2.destroyAllWindows()

• 可以控制圆形变化

• 凝视画面
  • 配合呼吸
• 可以做点更复杂点的吗？
  • 比如小球弹跳动画？？

随机游走的线段

import numpy as np
import cv2          
import time         
canvas = np.zeros((300,300,3), np.uint8)
cv2.imshow("Lines",canvas)
x = 150          
y = 150          
for num in range(0,30):
    point = (x,y)
    color = np.random.randint(0,256,size=(3,)).tolist()
    x = np.random.randint(0,300)
    y = np.random.randint(0,300)
    r = np.random.randint(1,5)
    print("num:",num,":color",color,":(x,y)",(x,y),":r",r)
    cv2.line(canvas,point,(x, y),color,r)
    cv2.imshow("Lines",canvas)
    time.sleep(1/6)
    cv2.waitKey(1)
cv2.destroyAllWindows()

• 具体效果

• 能做点更有规律性的吗？

地球和太阳动画

import numpy as np                       
import cv2                               
import time                              
import math                              
width = height = 300                     
sun_x = sun_y = 150                      
num = 0                                  
                                         
while cv2.waitKey(1) == -1:              
    num = (num + 1) % 360                
    radius = num / 360 * 2 * math.pi        
    img = np.zeros((width, height, 3),np.uint8)
    cv2.circle(img, (sun_x,sun_y), 15, (0,0,255),-1)
    earth_x = int(sun_x + math.cos(radius) * 100)
    earth_y = int(sun_y + math.sin(radius) * 100)
    cv2.circle(img, (earth_x,earth_y), 10, (255,255,0),-1)
    cv2.imshow("img",img)                
    time.sleep(1/100)                    
cv2.destroyAllWindows()

• 效果

• 能否在此基础上制作出月亮？

总结 🤔

• 这次设置了动画效果
• 感觉可以作为变量的因素
  • 颜色
  • 位置
  • 半径
  • 时间周期
• 可以做出一个钟表吗？🤔
• 下次再说👋