We are developing a user interface toolkit (buttons, labels, entries, etc) on top of OpenTK. Since our goals include custom appearance and a touchscreen friendly user interface we use today a NativeWindow with hidden borders and provide custom title bar and border.
Performing move and resize using the regular mouse events is not suitable since the mouse easily gets outside the window during these operations. In order to solve this it would probably be good to have specialized functions that start a move or resize operation and hand over it to the window manager to complete. In windows this is done by some calls to functions in "user32.dll". These require the native window handle as argument. This handle is for architectural reasons not available for applications that use OpenTK. So right now we face the issue of adding functionality to start move and resize operations to OpenTK. Is this of more general interest? Are there other preferable methods? Will an API like this be implementable on the other supported platforms as well?