The code can be built and works, but it does not work as I want. I want to use the mouse to draw a rectangle in a window. When the button is pressed, it starts to draw. When the button is released, the final rectangle should be filled and kept in the window.
I examined the code carefully and I really do not know why it does not work in that way. Please tell me.
**PS: I succeed to realize the functionality by small modification. What I want is just to know what is the problem in this program.**
using namespace std;
bool g_press = false;
void my_mouse_callback(int event, int x, int y, int flags, void* param);
IplImage *img = cvCreateImage(cvSize(500, 500), 8, 3);
cvAddS(img, cvScalarAll(255), img);
IplImage *temp = cvCloneImage(img);
cvSetMouseCallback("FUN", my_mouse_callback, (void*) temp);
以上就是I want to hold a filled rectangle in a window, but failed. Please tell me why.的详细内容，更多请关注web前端其它相关文章！