The shadow of the HairGroom asset is flickering.

I’m using the HairGroom feature.
I’ve attached to the skeletal mesh and the Groom shadows appear to flicker in and out.
It seems to be happening from a certain point in the local Y coordinate, and is stable at the top.
Changing the scale of the actor seems to have reduced the flicker, but I could be mistaken.
Also, the reason I thought it was a shadow is because the flickering can be reduced by reducing the value of Hair Shadow Density.
How can I get rid of the flickering here?
Please help me.

Hope this can be answered soon, I have the same issue and although decreasing the hair shadow density can partially solve the problem, it is still flickering a bit, and the render time goes way up pretty high.

It has resolved itself.
I used this video as a reference.


I haven’t figured out the details yet either, but it looks like a voxel shadow setting.
I was able to suppress it by entering the following ConsoleCommand.

“r.HairStrands.Voxelization.Virtual.VoxelWorldSize 1”

The video says the default is 1, but is the default value different in UE4.25?
Anyway, that solves the problem I was having.

Also, if you want this to be the default value, you’ll need to put it in your ini file. FYI.

Thanks! Worked like a charm

Thanks so much! In my case, which was just using a relatively short groom for a Metahuman character, I only needed to enable Deep Shadow on the lights to get rid of the noisy shadow on the hair. This seemed to give far more performance than tweaking the other settings shown in the video. However, I also disabled “Cast Shadow” for the Eyebrows, Eyelashes, Moustache, Beard, and Fuzz groom components, since the hair was so thin here a shadow would not be needed (Fuzz shadows should really be “off” by default for Metahumans).

It happens still in 5.1, these settings together with hair shadow density seems to have fixed that shadow flickering issue.

Thanks for posting a solution! Where did you get the setting from your screenshot?