Will Blender have the option of saving a sculpt mask, as some form of delimitation of the sculpt mesh, for the purpose of doing easy hiding and masking of complex mesh structures ?
Like Polygroups in Zbrush.
I’m thinking of creating a new BKE_pbvh_bmesh_update_topology that can preserve arbitrary markings for verts/edges, but its so hard . . . (should I do something else ?)
I don’t know of any plans to add it.
PBVH bmesh is only for dynamic topology, so it’s not the only place that would need to be updated, but yes BKE_pbvh_bmesh_update_topology would need to preserve custom data in some way.
I think there’s other sculpt features that are requested much more often though, so I’m not sure if making the code more complicated in this direction is the most useful thing.
OK bit to much, found another thing to (attempt) work on
Blender 2.8 has face-maps which are intended for rigging but could be used for any kind of face-grouping.
Unlike vertex groups each face can only be part of a single face-map, so I’m not sure if this fits you’re use case well.
Can we hire facempas in sculpt mode with multires mod?
Zbrush polygroups definitely only have 1 polygroup per 1 face, though. So in that sense that could work for it.