Hi Eric and fabianoberlim,
Thanks so much for the responses! I apologize I have been on vacation for the past week or so and have not been able to answer.
Eric–I would be willing to share my file with you. It’s about 2 gb. I can put it on Dropbox and share it with an email address of yours if you have one? I would like for it to stay private but at the same time getting to the bottom of this bug is very important as I can’t make final render videos without the black dots everywhere.
The materials in question are not using a LERP, but as for Math I think they might be. The materials were very similar to the ones that were set up in the U4 Quixel Sci-Fi Hallway example. I used a parent shader that allows up to 6 masks and there are Math nodes (such as Subtract, Power, Add, and more) that were added into the mix. I only have one normal map assigned in each shader so it should not be trying to blend 2 of those together. However it would be trying to blend the normal texture along with the Roughness Blend Mask texture, and a Specular Roughness texture.
My Radeon Driver version is: 14.100.0.0
I’m going to run the light test that you suggested earlier on July 17th. Let me know if you need more info? Thanks again for your time everyone!
I conducted the tests you suggested previously, and unfortunately results were the same with the marching black ants still present when Realtime is turned on afterwards. I’ve been trying Medium, Preview, and Production qualities for lighting:
Test 1: I selected all my lights and turned off Cast Shadows, rebuilt lighting.
Test 2: I deleted both sphere capture actors in my main hallway, still kept all lights with Cast Shadows turned OFF. Rebuilt lighting.
Test 3: Deleted sphere capture actors but kept original light settings (some with Cast Shadows on, some with off), rebaked lighting.
So after much experimentation and discussions here, we have narrowed down the issue to one related to a video card driver. We are in the process of setting up a test with a Radeon card and drivers. I will let you know as soon as I have the results.
I was finally able to reproduce the marching black ant lines on an Nvidia card with the Beta driver installed but switching down to the WHQL release driver clears the issue.
Thank you both for your help and I will keep you informed.