A face-masked appearance replaces one owner's items with several items that
together carry exactly the same triangle corners (#4404): the textured face
set and the retained face set of an evaluated occurrence. Both sides name
every ordinal of one reference surface exactly once, so the same record
inverted describes the join that Undo performs.
A face-masked appearance replaces one owner's items with several items that together carry exactly the same triangle corners (#4404): the textured face set and the retained face set of an evaluated occurrence. Both sides name every ordinal of one reference surface exactly once, so the same record inverted describes the join that Undo performs.