wglMakeCurrent() can be called concurrently from any thread, as long as you don’t attempt to make a context current in thread2 that is already current in thread1. A context can only be current to one thread at any time.
Apart from this, your scenario (rendering into the same HDC concurrently via two threads) is most probably not possible and will result in an error.
I use the same hdc. Since I use the function getDC to get the hdc, i thought there was no need to create 2 hdc, one per thread.
Actually, this works nice… How would you create the second hdc ? Calling getDC in the second thread ?