opencv Python学习笔记（三）调色板加跟随鼠标绘图

import cv2
import numpy as np


drawing=False
ix,iy=-1,-1
modes=True

def nothing(x):
    pass


def draw_cricle(event,x,y,flags,param):
    global ix,iy,drawing,mode
    r=cv2.getTrackbarPos('R','image')
    g=cv2.getTrackbarPos('G','image')
    b=cv2.getTrackbarPos('B','image')
    color=[b,g,r]
    if event==cv2.EVENT_LBUTTONDOWN:
        drawing=True
        ix,iy=x,y
    elif event==cv2.EVENT_MOUSEMOVE and flags==cv2.EVENT_FLAG_LBUTTON:
        if drawing==True:
            if modes==True:
                cv2.rectangle(img,(ix,iy),(x,y),color,0)
            else:
                cv2.circle(img,(x,y),100,color,1)
    elif event==cv2.EVENT_LBUTTONUP:
        drawing=False




img=np.zeros((500,500,3),np.uint8)
cv2.namedWindow('image')

cv2.createTrackbar('R','image',0,255,nothing)
cv2.createTrackbar('G','image',0,255,nothing)
cv2.createTrackbar('B','image',0,255,nothing)
cv2.setMouseCallback('image',draw_cricle)
while(1):
    cv2.imshow('image',img)
    k=cv2.waitKey(1)&0xFF
    if k==ord('m'):
        modes=not modes
    elif k==27:
        break