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I want to create a Paint application with adjustable colors and brush radi.

I have written the code for this as follows:

import cv2

import numpy as np

def nothing(x): pass

drawing = False # true if mouse is pressed

mode = True # if True, draw rectangle. Press 'm' to toggle to curve

ix,iy = -1,-1

def draw_circle(event,x,y,flags,param): global ix,iy,drawing,mode

if event == cv2.EVENT_LBUTTONDOWN:
    drawing = True
    ix,iy = x,y

elif event == cv2.EVENT_MOUSEMOVE:

    if drawing == True:
        if mode == True:
            cv2.rectangle(img,(ix,iy),(x,y),(0,255,0),-1)
        else:
            cv2.circle(img,(x,y),ra,(0,0,255),-1)

elif event == cv2.EVENT_LBUTTONUP:
    drawing = False
    if mode == True:
        cv2.rectangle(img,(ix,iy),(x,y),(0,255,0),-1)
    else:
        cv2.circle(img,(x,y),ra,(0,0,255),-1)

img = np.zeros((1024,1024,3), np.uint8)

cv2.namedWindow('trackbar')

cv2.createTrackbar('Red','trackbar',0,255,nothing)

cv2.createTrackbar('Green','trackbar',0,255,nothing)

cv2.createTrackbar('Blue','trackbar',0,255,nothing)

cv2.createTrackbar('Radius','trackbar',10,200,nothing)

ra = 0

switch = '0 : OFF\n1 : ON'

cv2.createTrackbar(switch,'trackbar',0,1,nothing)

while(1):

cv2.imshow('trackbar', img)
ra = cv2.getTrackbarPos('Radius', 'trackbar')
cv2.setMouseCallback('trackbar', draw_circle)
k = cv2.waitKey(1) & 0xFF
if k == ord('m'):
    mode = not mode
elif k == 27:
    break

r = cv2.getTrackbarPos('Red','trackbar')
g = cv2.getTrackbarPos('Green', 'trackbar')
b = cv2.getTrackbarPos('Blue', 'trackbar')
s = cv2.getTrackbarPos(switch, 'trackbar')

if s==0:
    img[:] = 0
else:
    img[:] = [b,g,r]

cv2.destroyAllWindows()

But it is not working properly. Trackbar for changing RBG color is working but the circle and rectangle are not drawn on mouse click. Anyone can tell me what i am doing wrong in this code?

I want to create a Paint application with adjustable colors and brush radi.radius using Trackbars.

I have written the code for this as follows:

import cv2 cv2 import numpy as np np def nothing(x): pass pass drawing = False # true if mouse is pressed pressed mode = True # if True, draw rectangle. Press 'm' to toggle to curve curve ix,iy = -1,-1 -1,-1 def draw_circle(event,x,y,flags,param): global ix,iy,drawing,mode ix,iy,drawing,mode if event == cv2.EVENT_LBUTTONDOWN: drawing = True ix,iy = x,y elif event == cv2.EVENT_MOUSEMOVE: if drawing == True: if mode == True: cv2.rectangle(img,(ix,iy),(x,y),(0,255,0),-1) else: cv2.circle(img,(x,y),ra,(0,0,255),-1) elif event == cv2.EVENT_LBUTTONUP: drawing = False if mode == True: cv2.rectangle(img,(ix,iy),(x,y),(0,255,0),-1) else: cv2.circle(img,(x,y),ra,(0,0,255),-1) img = np.zeros((1024,1024,3), np.uint8) cv2.namedWindow('trackbar') cv2.createTrackbar('Red','trackbar',0,255,nothing) cv2.createTrackbar('Green','trackbar',0,255,nothing) cv2.createTrackbar('Blue','trackbar',0,255,nothing) cv2.createTrackbar('Radius','trackbar',10,200,nothing) np.uint8) cv2.namedWindow('trackbar') cv2.createTrackbar('Red','trackbar',0,255,nothing) cv2.createTrackbar('Green','trackbar',0,255,nothing) cv2.createTrackbar('Blue','trackbar',0,255,nothing) cv2.createTrackbar('Radius','trackbar',10,200,nothing) ra = 0 0 switch = '0 : OFF\n1 : ON' cv2.createTrackbar(switch,'trackbar',0,1,nothing) while(1): ON' cv2.createTrackbar(switch,'trackbar',0,1,nothing) while(1): cv2.imshow('trackbar', img) ra = cv2.getTrackbarPos('Radius', 'trackbar') cv2.setMouseCallback('trackbar', draw_circle) k = cv2.waitKey(1) & 0xFF if k == ord('m'): mode = not mode elif k == 27: break r = cv2.getTrackbarPos('Red','trackbar') g = cv2.getTrackbarPos('Green', 'trackbar') b = cv2.getTrackbarPos('Blue', 'trackbar') s = cv2.getTrackbarPos(switch, 'trackbar') if s==0: img[:] = 0 else: img[:] = [b,g,r] cv2.destroyAllWindows() cv2.destroyAllWindows() But it is not working properly. Trackbar for changing RBG color is working but the circle and rectangle are not drawn on mouse click. Anyone can tell me what i am doing wrong in this code?