_UnsetNeighbourCorner
_UnsetNeighbourCorner(fLeftTopCrossing->LeftBottomCorner(),
_UnsetNeighbourCorner(fLeftTopCrossing->RightTopCorner(),
_UnsetNeighbourCorner(fRightTopCrossing->LeftTopCorner(),
_UnsetNeighbourCorner(fRightTopCrossing->RightBottomCorner(),
_UnsetNeighbourCorner(fLeftBottomCrossing->LeftTopCorner(),
_UnsetNeighbourCorner(fLeftBottomCrossing->RightBottomCorner(),
_UnsetNeighbourCorner(fRightBottomCrossing->LeftBottomCorner(),
_UnsetNeighbourCorner(fRightBottomCrossing->RightTopCorner(),
inline void _UnsetNeighbourCorner(Corner* neighbour,