If true, the node's Z index is relative to its parent's Z index. If this node's Z index is 2 and its parent's effective Z index is 3, then this node's effective Z index will be 2 + 3 = 5.
See Implementation
If true, the node's Z index is relative to its parent's Z index. If this node's Z index is 2 and its parent's effective Z index is 3, then this node's effective Z index will be 2 + 3 = 5.