Duplicate of UE-20645
While testing another fix I noticed HISM LOD transitions are not working in Main or 4.9 branch. There is no screen-door effect and multiple LODs seem to be rendering simultaneously compared to 4.8.
1. Open KiteDemo in the editor
2. Load Forest_and_Lake and Starting_Shot sublevels
3. Press the #4 shortcut key and look at some of the trees near the waters edge
4. Multiple LODs are rendering simultaneously and there is no transition between them.
Viewing in Lighting Only makes it easier to see what's going on.
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-20297 in the post.