This issue has been closed as 'Won't Fix' due to an extended period of time without updates. If this issue is important to you please let us know by posting on the AnswerHub or UDN, and Epic will re-open the ticket for further review.
Currently, precomputed visibility volumes do not seem to alter occluded primitives, nor do they show visibility cells when r.ShowPrecomputedVisibilityCells 1 is entered.
Repro: [reproduced internally]
1. Open Editor (Any project)
2. Select Volumes in placement mode
3. Drag a pre-computed visibility volume into level
4. Place static meshes within bounds of volume (adjust bounds as necessary to compensate) - For the test SM_Rock, SM_Shelf, and MaterialSphere were all used
5. Build level
6. In the console commandline, type both stat initviews (enter) then r.ShowPrecomputedVisibilityCells 1 (enter)
Occluded primitives remains at 0
Visibility Cells are not rendered
Statically Occluded Primitives should show >0 and visibility cells should be rendering in viewport
There's no existing public thread on this issue, so head over toAnswerHub just mention UE-3634 in the post.