Distance Field thin mesh issue for lumen

Hi, does anyone know how to properly manage the distance field meshes when they are thin, because I have some models like boards or sheet metal and they have holes in the mesh. I set the distance field detail in the settings, but it doesn’t help and costs more memory. The only thing I found on the internet is



from this
link https://advances.realtimerendering.com/s2022/SIGGRAPH2022-Advances-Lumen-Wright%20et%20al.pdf
but I don’t really know how to use it, maybe someone has another idea or knows how to solve this problem

Some options include thickening the mesh, enabling two sided distance fields sometimes helps, increasing the distance field resolution in project settings, or use a replacement mesh for distance field generation - I’m sure there are others.

thanks for your answer, but unfortunately two sided distance fields will not help, there are still large holes
increasing the resolution of the distance field in the project is not the best option because it increases the requirements for each object.
replacement mesh is sometimes helpful and sometimes not.
In general these options are sufficient but not in this case.
Too bad there are no clear options on how to manipulate exactly:(

Hi!
I just had a very similar issue and stumbled upon this topic, I found the console command which controls the distance field thickness:

r.DistanceFields.SurfaceBiasExpand

The default is around 0.01 you can try increasing it but for me the solution was to set it to 0

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Hi!
Thank you for your answer, is very helpful. Can you give me the source from where you found this command? I would like to read more about it and what the exact difolt value is.

Hi, sorry for the late repply!

The default value is 0.25
I found the command by brwoswing trough console commands in engine, the only resource I can found about it is on this site: UE5 Console Variables and Commands

“Fraction of a Mesh SDF voxel to expand the surface during intersection. Expanding the surface improves representation quality, at the cost of over-occlusion.”

thank you very much :slight_smile: