Quick lighting question

Development Rendering
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1

Hey guys, just a quick lighting question.

I’m working on a project with fully procedural rooms and fully dynamic lighting (lightmass is turned off). I would like some rooms to be well lit, and some rooms to be very very dark.

The problem seems to be I’m unable to have very very dark rooms if I use a skylight. (I was going to use light channels as a solution until I found out that you can’t use them with skylights, other people seem to have a similar problem with caves).
https://forums.unrealengine.com/unreal-engine/feedback-for-epic/112524-lighting-channels-for-sky-light

My options seem to be -

  1. Put point lights EVERYWHERE (if I have no skylight and no lightmass it seems very hard to get corners etc lit).
  2. Use streaming levels for the different rooms, which will be extremely fiddly to the point of unusable in my situation, seeing as there is a lot of rooms and they are all dynamically generated etc…
  3. Use VXGI, which I would love to and is perfect for my game (small dynamic rooms), but I’m on version 4.20 and it has no sign of being updated by NVidia for almost 6 months (assuming they have moved to to ray tracing).

Am I missing something? Is it really this hard to have different “base” light levels in a dynamic level? I’m open to any suggestions at this point have spent 20+ hours on this issue.

Thanks.

Edit: also looked into LPVs quite a bit, but apparently these haven’t been fully supported for years and seem to be buggy with newer materials etc.

2

Hi there , I think your first option might be the best try to keep the attenuation radius as low as possible as well as the intensity. I have used such a set up for my game but its not procedural generated though. Then there is LPV however it cant be used for interior scenes.

3

Hey there,

Thanks for your suggestion, the first option was sort of a joke. There’s no real way to light the entire place with point lights, we would be talking literally 1000s of lights just to light one level. And it would look terrible! (lots of light and reflections etc where there clearly shouldn’t be, just for the sake of lighting up an area that would other whys be pitch black).

Also I actually looked into LPV (and other GI options) quite a bit, it doesn’t look like LPVs have been properly supported for years (as apparently it was never actually the epic teams tech to begin with) and there’s plenty of people complaining it has bugs and issues with newer versions of UE4 on the forums.
The other GI options I looked into where either really expensive or quite low quality (there’s some “GI blueprints” on the marketplace that just use a bunch of point lights but they look pretty crappy and have some pretty serious limitations.).

I’ll update my question with this comment.