Hi, after upgrading to 5.6, I’m noticing temporal artifacts in Volumetric Clouds. This seems to be related to changes made to Volumetric Render Target reconstruction and upsampling. Is this a known issue or do we need to adjust cvars to fix these artifacts? I’ve attached videos of demonstrating the issue in 5.6 and a comparison of 5.5 where it does not occur.
Steps to Reproduce
Start Editor -> Open level VolumetricCloud -> Create a sphere or other object to occlude the clouds and place it in front of the camera -> Shift the viewport camera left and right quickly
Hi David,
I took a quick look at your videos, but I cannot say right away why the volumetric cloud reconstruction is failing for you. According to our perforce history, there have also been a number of changes in that code between 5.5 and 5.6, so it will take some time for me to find the root cause of this. Would it be possible for you to also share the repro project with me to ensure we are on the same page? Lastly, as you know, we will be on a two-week summer break starting Monday. If this reconstruction issue urgently blocks you, please let me know, and I will try to look into escalating your case.
Hi again. I am just getting caught up with our cases here post-break. Just to keep things consistent, could you please send over the repro project as-is and your project configurations? I assume they will likely not have changed, but it would be good to have them anyway to ensure that there were no accidental changes made to the project that could have caused the artifacts in the videos.
Hi David,
Sorry for the long radio silence, but I have some positive news. I discovered that the VCC artifacts you are seeing were introduced as part of our work for the Witcher 4 tech demo at Unreal Fest. Two fixes were recently added to UE5-Main, but they have not been integrated into the 5.6 release yet. Can you please try backporting the following Changelists 44160343 and 44161482 into your build and report back if they end up fixing the reconstruction artifacts you are seeing?
Cheers,
Tim
Okay, I’m glad to hear that! I will go ahead and close out the ticket now, but if you have any further questions, do not hesitate to reach out again.
Hi, thanks for looking at this. The videos were made using a fresh copy of 5.6 without any changes, do you still need a repro project?
This is just a copy of 5.6 without any changes and using the default EngineTest project. If you absolutely need me to send a copy of EngineTest, it will take me some time to resync a copy of 5.6.
Hi thanks, I did check those out and they are looking great so far, thanks!