distancefield generated displacement shadow

[schweinerussel]

i am trying to shape a landscape via distancefields,
but i have the problem that the deformed geometry casts no or incorrectly positioned shadows (VSM).
i have already tried this in various unreal versions without success and therefore do not assume a bug.
generally the shadow casting of displaced geometry works, but as soon as distafields are addressed in the shader, errors occur.
maybe someone has an idea
thanks in advance

[ClockworkOcean]

I think that using the DF calculation to feed a lerp between min and max displacement would be the way?

I turned off DF and shadows on the green mesh. It looks the same with Nanite and displacement.

[schweinerussel]

Thanks for the Reply
but if i’m not mistaken
in your example only the cube casts shadows and not the “ground mesh”
i have tried the
lerp variant and for me the result looks the same

on the red area, there should be shadow

[ClockworkOcean]

If I turn ‘cast shadow’ back on for the plane, and use Nanite, it doesn’t help

and goes garbage up close

Is this even supposed to work? I know it didn’t a few months ago. Where did you get the info, is it a 5.6 thing etc?

[schweinerussel]

i dont know if its supposed to work.
but in ue4 it did
im checking it since 5.0 without luck, so its not 5.6 related.
i thought maybe its possible and im missing something.
i have also tried different shadow types without success
except contact shadows which had other issues

[ClockworkOcean]

I don’t think Nanite existed in UE4

[schweinerussel]

the issue is not nanite related (also wpo doesnt cast shadow )
and in ue4 there also was wpo and displacement

[ClockworkOcean]

Yes

I don’t think you can get good shadows from dynamically displaced meshes, at the moment… would love to hear otherwise.

[schweinerussel]

just for clarification, shadow casting in general working from displaced meshes
in this case from a generated noise.
afaik its just the distance to nearest surface which
doesn’t get recognized correctly

[ClockworkOcean]

Have you displaced that mesh permanently?

I mean if displacement casts a correct shadow, it would work no matter what basis you used ( texture or distance field ).

[schweinerussel]

thanks for your perseverance

@ClockworkOcean

Have you displaced that mesh permanently?

no, its a noise function in the material

@ClockworkOcean

I mean if displacement casts a correct shadow, it would work no matter what basis you used ( texture or distance field ).

I would like this to be true,
but based on what I have tested, I don’t think this is correct
see below

the hill, created by the cube should also cast shadows.

i assume something with the distance field calculation in the shader must be calculated differently
but i have no idea what

[ClockworkOcean]

Yes, bizarre