Blender Git Loki

Sculpt: Preserve Mesh visibility from edit mode using the Face Sets

Before this change, when users switch from edit mode to sculpt mode, the
entire mesh would be visible. Even if in the edit mesh mode part of it was
set to invisible.

With this change the visibility is preserved, by creating a separate face set
for the visible and invisible parts of the mesh and setting their initial visibility.

Implementation details: This adds a function to initialize a new Face Set
datalayer taking the current mesh visibility into account which is stored
in the ME_HIDE flag of the vertices.

Reviewed By: sergey

Differential Revision: https://developer.blender.org/D8901