We experience the exact same issue, but in our project there isn’t even “flickering”. Changing the FOV simply turns off all lights completely. That means if you try to zoom with our sniper rifle, it suddenly gets dark in the level. We are on 4.8.3.
I can also confirm that the issue is depended on either the number of objects in the level or at least the amount and/or detail of all meshes (or their distance fields) in the world. If we remove some higher poly objects the issue doesn’t occur any more.
Is there anything we can do to further help in finding the cause of the issue?
[Edit] I opened up the Kite Demo to check if I can reproduce the issue there. Turns out all you need to do is set the FOV to random values (or lerp between two values with a sin function or so) in Tick to turn off all lights and shadows. Should (hopefully) be reproducible on any machine.
Hello FacePalm.exe,
After quite a bit of consulting on our end we have come to the conclusion that the issue does lie within the distance field shadows.
To that end I created a test within the project you linked second.
1.) I deleted one of the walls.
2.) I created a ton of meshes in the level. Yes, they are meshes and not painted with foliage.
3.) I then Played the game.
4.) I looked down a row of trees and noticed at the very extreme end of the row I noticed the flickering that you reported.
5.) I then went to the directional light and changed the distance of the shadows to something a little closer.
6.) This seemed to fix the issue.
7.) At a certain point the engine will have a hard time calculating shadows, especially those that are dynamic and will need to be calculated in real time.
8.) I created a video to reflect the steps I used to create this. At this point in time, this is a limitation of the calculation of shadows at certain distances.
9.) I realize that this may not be a viable solution because of the large open world dynamic you have for your game.
This is the youtube link: - YouTube
Let me know if this could possibly be a solution for you. If not you may want to consider baking your shadows on larger objects and then using dynamic lighting assigned through blueprints for your movable objects.
Thanks,