Having trouble creating a class based implementation of OpenCV's mouseCallback function

Question

As the title suggest, I\'m having some trouble implementing OpenCV\'s mouseCallback function in a class based C++ structure. Allow me to explain. I have defined a class called B

Answer 1

Since a member function takes a this pointer, you will need a static wrapper function. Typically, you use the param parameter to be the address of the object that the member function belongs to, so you end up with something like this:

...
static void mouseCallback(int event, int x, int y, int flags, void *param);

void doMouseCallback(int event, int x, int y, int flags);

And then inside the mouseCallback:

void BriskMatching::mouseCallback(int event, int x, int y, int flags, void *param)
{
    BriskMatching *self = static_cast(param);
    self->doMouseCallback(event, x, y, flags);
}