virtual void LeftDown(Point pos, dword flags) {
    if(pos.x >= someCtrl.GetPos().x.GetA() && pos.x <= someCtrl.GetPos().x.GetA() &&
       pos.y >= someCtrl.GetPos().y.GetA() && pos.y <= someCtrl.GetPos().y.GetA()) {

                PromptOK("clicked inside");
    }
}