Trackball::Button QT2VCG(Qt::MouseButton qtbt,  Qt::KeyboardModifiers modifiers)
{

	int vcgbt=Trackball::BUTTON_NONE;
	if(qtbt & Qt::LeftButton		) vcgbt |= Trackball::BUTTON_LEFT;
	if(qtbt & Qt::RightButton		) vcgbt |= Trackball::BUTTON_RIGHT;
	if(qtbt & Qt::MidButton			) vcgbt |= Trackball::BUTTON_MIDDLE;
	if(modifiers & Qt::ShiftModifier   ) vcgbt |= Trackball::KEY_SHIFT;
	if(modifiers & Qt::ControlModifier ) vcgbt |= Trackball::KEY_CTRL;
	if(modifiers & Qt::AltModifier     ) vcgbt |= Trackball::KEY_ALT;
	return Trackball::Button(vcgbt);
}