Very dark shadows of custom Terrain

Hi,

currently i struggle to find a solution or cause of this dark shadows and strange lighting.

i found some topics about dark shadows.
i already changed the directional light to dynamic, when i add a sky light nothing happens.
i think the problem is that the terrain is a 1000km radius planet so the sky light needs to scaled or something?

raytraced shadows create strange shadows when used with dynamic shadows.

in this screenshot i use ddx, ddy to calculate the normals. so i think it’s not an issue with normals

As with all lighting issues, It is still most likely the normals. You might consider reducing the strength of the calculated normals by reducing the intensity of the RG channels and see if that resolves the issue.

i tried you suggestion and it helped. :slight_smile:
by any chance do you know how to scale the sky light to work with spherical worlds?

Glad it helped - but sorry, I haven’t worked on spherical worlds.

well… the skylight is basicly an hdri/cubemap. to get uniform lighting you gotta use a uniform color. like a white hdri/cubemap and adjust the single color you have underneath.

about those shadow artefacts: it’s probably a precision issue. you are not using a real 1000km sphere? do you? if you go that big you gotta lower your “world scale” to a range that is acceptable for rendering. like 1 unit is like 10km. that’s how space rendering metrics work.

hi,
thanks for this hint. but one question. isn’t the newest version of ue5 using double precision?

it’s using double precision for the world positioning. most gpus uses normal precision tho. on 10 and 20 series or amd gpus you can even use half precision for a compute speedup of roughly 2x, theoretical. the 30 and 40 series do not support that.