I guess it has something to do with it being black but this is issue has been spotted in 2 separate sellers’s products on fab. Moreover, it’s definitely a material issue, not the mesh. Black dots and grain can be seen even on small previews in a content drawer:
i don’t know, i wonder if maybe the normals on the concrete are very grainy.
and when bumping the quality it uses a higher resolution for the normals leading to more contrast, making it more obvious or introducing those artifacts.
For some reason, this particular’s material blending was set to 12. The lower it is, the better it look up-close. Ideally if it’s turned off. I am new to UE and yet to learn what that is but the main question is why does it affect an unobstructed mesh in such way at all. Someone more experienced is more than welcome to shed a light on the cause but for everybody else struggling with it and finding this tread - kill that blending thing with fire.
congrats!
i have no idea really.
but that parameter seems like something specific to that material and not something “from ue”.
so there might be something weird on the setup of that material. that in turns trigger a side-effect on ue.
Hi, as far as I know lumen does not really support opacity blending using pixel depth offset or dither temporal aa (both are cheap ways to do such blending but lead to that black noise with lumen, especially if the mesh is in shadow). Had that exact same issue two days ago trying to create a cheap water material with dither temporal aa opacity blending, took me some searching to find the reason
And if you set global illumination to below high, then lumen is disabled.
If you need to blend the mesh with the landscape, you could use a runtime virtual texture instead.
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