distance field meshes flickering on a big level [5.3.2]

Hello,

since may 6th my distance field shadows have started flickering crazy strong, like “epilepsy warning” strong.
I checked around, learned a bit more about the whole thing, saw other similar/very same questions, but I still don’t have a solution for mine.

To note is that I have a big level with many actors (almost 5000) and a lot of foliage. On this level, as I place around some ivy to test an area I notice flickering start.
on another empty level the flickering does not happen.
Since then, all the distance field meshes are flickering as described above.

I deleted the meshes I had just placed, sort of a rollback to see if I had “surpassed” a limit, flickering is still there.
I manually removed “affect distance field lighting” on all meshes except one, but it still flicker.
I even ended up toggling off the “generate distance field meshes” in the editor settings, but I need it for some of my foliages that otherwise look terrible.

Both in PIE and in packaged, both with and without lumen, it keeps on flickering.

In the picture I uploaded it show the two “statuses”, it flicker from one to another every 0.05 seconds. (this is just one example).

I have an NVIDIA 2070 (rtx i think) but the latest drivers are from 16th of april (while the issue appeared on 6th of may).

It’s driving me crazy not knowing what is causing it.

2 Likes

Answering in case anyone else will end up with the same issue.

I did not fix it, but I was able to find a work-around by removing the distance field mesh from all of my meshes except the trees (because they needed the extra depth of light to look nicer).
Eventually as I added more stuff to the level the problem reappeared: since I had not deactivated the “create mesh distance fields” any new item had the mesh distance field, so I went to remove it/tick the “affect distance field lighting” in each static mesh and the flickering disappeared.

I eventually moved off lumen, distance field meshes and virtual shadow maps to move onto using cascaded shadow maps as for now it seems much simpler and easier to set up, while also being much less performance heavy.