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Problème with basic lighting

Hi everyone!

I require help for my lighting learning.
I started a blank project with starter content.

I build a floor, with wall and roof… I’ve only a directional light source. And i’ve some strange effectes on lighting.

I try to adjust my lightmass, my light, the lighting quality … but nothing solve my problem.
Here is a capture from my UE viewport.

We can see difference in lighting on my slabs or walls, or a white lighting in wall corners.

Have you rebuilt your lighting?

Yes, i rebuilt the entire solution like the lighting!

Don’t build your walls/floor that way, make them one object

Hum ok, but, that’s not what it did in this tutorial?!

It look like a quite strange to have this lighting problem!

That problem could be caused by my hardware?!

If you look at the screenshots, it has the same issues (it’s due to how each object is processed for lighting individually)
You can hide it in some cases like they did by putting a pillar over the seams or by using a different material.

OK just a total guess here. I would expect this kind of result if you are using mixed lightmap resolutions. Lets say object A has a lightmap resolution 1024 and a connecting object B has a resolution of 32 your definitely going to have a density problem.

A workflow tip, when I’m setting up lighting, I’ll usually set my in scene resolution to something crazy as to per frame rendering. Average map object = 512 Building surface = 1024 Singe plane ground 2048. Over time I’ll back down the resolution

Due to the way lightmass works, each mesh is processed in parallel, so indirect lighting can look different in adjacent meshes like that. Like @darthviper107 said, it’s better to make contiguous surfaces a single static mesh. You can even use the “merge actors” functionality in the editor if you don’t want to re-export anything.

If you really can’t avoid using multiple meshes, you can reduce the differences by increasing “indirect lighting quality” to 20+, reducing “lighting smoothing” to 0.5~0.7 and rebuilding lighting with “medium” quality or higher (“preview” ignores most of those settings). If you still get artifacts, you can then try to reduce “static lighting level scale”. Also, check your lightmap resolution using the lightmap density view mode.

Okay guys, i’ll test all of that! I’ve download the sample scene from koola’s work, I’ve many habits from 3dsmax and Vray … so i’ve a lot of this to learn before have a conclusive result!
Thanks ! :slight_smile:

I’m sorry but this is totally wrong!! 20+ quality!? :smiley:

So Uohcnam if you want to keep your modular pieces: no problem!
All you have to do is set your indirect scale to 0.1 under world/lightmass and set smoothness to 0.6 and voila the differences will disappear! :wink:

However, you will improve performance by reducing the number of objects, in this case since the objects are so simple there isn’t much reason to make them modular.