SUGGESTION : Adding cv::moveWindowfunctionality

[KalanaRatnayake]

i was using your header file and needed to use cv::moveWindow() as well. So to make things easy, i created a cvui::init() and cvui::watch() respectively. i have attached the modified cvui.h for inspection. hope it was at least a help to develop this further. cvui.zip

[Dovyski]

Thank you for your contribution! I will take a look at it and see if it can be integrated into the next release.