Built Lighting Ruined my Level

NOTE: Before is on the right-hand side. After is on the left.

I finished my scene and level a few days ago.

I had previously tried to build the lighting at 500 object intervals, but each time it crashed. So without giving it a second thought, I finished the level with 8,000 unbuilt objects. As you can see in the photos, everything was rendering fine as is.

The final day came. The only thing to do was build the lighting. I’d hoped doing so would help increase the performance of the scene. So I ran the DumpUnbuiltLightInteractions turned on the color debug and hit build. The Lighting Build finished and crashed on reflections, so I spent a day researching how to increase my PC’s performance.

I changed some NVIDIA control panel settings, Increased the r.streaming.poolsize limit to 7000, went into the settings of the project, changed the PoolVRAMPercentage to 0, and installed NVIDIA DLSS.

Then I came back to the editor and hit build lighting.

The lighting built fine, and it even completed the full process. Now, however, since building the lighting on my project I have large black patches on the walls of my buildings and within my scene. If I re-drag the lights, it seems to fix the issue, but doing so prompts me to rebuild the lighting on any of the objects the light touches. Rebuilding the lighting to clear the prompt then results in the shadows and black patches inside and outside the buildings of my scene coming back.

I have 3D assets I’ve downloaded from CG Trader, The Unreal Engine Store, and A23D. Some of the assets have a UV Channel 0. Some of the assets have a UV Channel 0, 1. Some assets have a UV Channel 0, 1, 2, etc.

I’ve used Unreals UV Editor to fix a large portion of the assets, using the Auto UV or changing the UV Channel of the assets that do have more than Channel 0. I’ve even rebuilt the materials from scratch that came with the downloads from CG Trader, Unreal Engine Store, and A23D. But the only thing that seems to work is re-draging the point lights down and not rebuilding the lighting. Most of the errors involve overlapping UVs, but I don’t have access to the build data. It may be worth noting I imported the objects as FBX files. With the Default settings on in addition to “combine meshes,” but that is the only additional setting I changed in imports.

There also seems to be some issue with my glass and mirror materials as the glass is now reflecting the sky and the mirrors refuse to reflect anything.

The photos really don’t do justice to how horrendous it actually looks on my screen.

This has been extremely frustrating. I am also a complete newbie when it comes to lighting. I just want my level back to what it was two days ago :joy:

First question right up front, which may be dumb: Do you actually want to use static lighting?

I’m assuming you do, but somehow a lot of people end up building light when they don’t actually care is the lighting is moveable or not…

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That’s a good question.

I’ve been trying to understand the use of static or stationary light in regard to nanite. It seems that nanite can only utilize some forms of lighting.

Really, the biggest thing for me is the performance of my editor and the resulting game. That is priority number one.

I can’t seem to find any clear or concise articles or tutorials on how to properly use nanite within a level to both increase performance and fidelity without being constrained to a specific type of lighting.

So to answer your question, I don’t know enough about lighting, in general, to really answer that question.

I’d like to use nanite to increase performance and the lighting it requires :man_shrugging: I hope that makes sense.


To add. I currently don’t have Nanite enabled on any of my assets within my level. I removed them all with the Nanite management tool yesterday. And moving the lights no longer fixes the issue or the weird blurring of the textures as it did before. So I removed the blueprint lights and recreated them with static meshes and point lights.

I don’t really know that much about Nanite, but I don’t think it supports static lighting. [ I was just sitting here re-reading that, and I don’t think actually it makes any difference, because Nanite is dealing with the poly structure, and static lighting is embedded in the lightmap ]

Nanite does seem to be getting better, but one of the main reasons you might want to increase efficiency is for those with older machines. They will not be able to Nanite anyway, as I don’t think, it works with DX11.

Static light does help a lot, but again, you’d really need to be targeting very old, or very modern, limited, platforms, like VR.

At the moment, probably one of the best things you can do for efficiency, is to turn off Lumen, and use low poly assets. IE game assets, not the absurd high density assets that are appearing on the marketplace, just because they can use Nanite.

Someone might come along and correct this, as I don’t really want to spend hours leafing though release notes, but I hope it’s broadly correct.

So it all boils down to, what is your target platform?

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Target platform would be PC.

PC as the first release and beta testing and then game consoles waaaay down the line. If game consoles are even conceivable.

I imagine the steam marketplace to be one of the early places I approach in release.

I’ve been working on correcting the UV maps of all the assets turning off static and making them stationary. But even after correcting the UV maps, which in some cases destroys the asset :smiling_face_with_tear:, it still hasn’t fixed the blurry, smudged texturing or the differences in the walls and black marks. Specifically, in one of the pictures above I circled on the floor where the wood textures is half perfect and half horrible.

The “overlapping” UVs is the only warning on the message log (there are a lot of them) usually only after I turn stationary objects back to static and there are no red errors presenting.

You think turning off lumen is best for quality of picture and performance and will fix the issue?

I can always change the quality of what people get to play during the export and rendering correct?

Can I turn off lumen on a level-to-level instance?

I have an entirely different level that is much more important than the one I’m working on which I’m hoping to not effect, as I’ve spent months getting that where I want it to be and i doubt i could rebuild that as easily as this level.

You can turn Lumen on and off with a console command.

However, going down the static light route, is a world of pain you’ll never get away from. That’s why I’m bringing it up. You don’t really need it unless you’re targeting old hardware.

Even if you try and include it as an option, it will dominate your entire development experience, and you won’t be able to focus on what really matters.

Just having correct UV maps isn’t the answer, you also have the resolution of the lightmap that’s made on import from that. How modular the assets are, and many other things.

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So what exactly is my solution?

Step 1: Turn off lumen.

Step 2: Change all assets from Static to Stationary?

Step 3: Turn off Nanite?

So. I’ve done the following.

  1. I’ve turned Nanite off of all objects.
  2. I’ve turned the Global Illumination settings to Standalone Ray Traced
  3. I’ve turned all assets from Static to Stationary (that I could)
  4. I’ve redone all the UV maps for the (3345) actors in my scene.
  5. I’ve changed my Shadow Map Method to “Shadow Maps”
  6. I’ve added (28) Lightmass Importance Volumes to the every room of the main house and the houses players will be able to approach.
  7. I’ve rebuilt the Lighting.

Good news. All errors have been eliminated.

Bad news. All the Dark Squares, Terrible Texturing, Poor Image Quality, etc, etc, is still present in my Level.

There’s also some kind of fuzzy pixelation whenever I get close to any asset and I’m navigating via the viewport. Fast Camera movement seems to make it worse.

You see this big fat red error that’s in all your pictures?


That’s why you’ve got fuzzy textures.

This console command is the solution

r.Streaming.PoolSize 6000

That’s 6GB, you can set your own.

At the moment, your texture streaming buffer is way too small, I can see that from here. After you fix that, I think everything will look better, apart from reflections. That’s a problem with Lumen.

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Thank you for reaching back out!

I appreciate your time and your help and i apologize if my frustration is bleeding into my reaponses. I’m trying not to throw my computer through the wall :joy:

Each time I get that error I set and reset the streaming pool size :cry: I think im currently at 7000 but I’ll bump it up to 10 and see if that helps.

I’ll keep you updated!

Thanks again for your help and patience :pray: I do sincerely appreciate it

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No worries :slight_smile: If you have to keep upping the streaming pool, quit the editor and restart. Then set the streaming pool to your amount of VRAM, then load the offending level again. If it still goes over, then you’re just using too many textures.

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Here’s the thing.

Upping the texture streaming pool, also did not correct the issue.

Everything in this level was perfect and how I wanted it. Everything was working 100% fine with the factory default settings.

I had just completed the final item I was placing in my scene, and the ONLY thing I had to do was “rebuild the lighting” according to the error messaging at the top.

I ran the commands I was prompted to do. “DumpUnbuiltLightInteractions”, “Use Error Coloring,” and from the 1st successful lighting rebuild, my scene has been ruined.

I’ve made all these changes, and it hasn’t corrected the issue. It’s only made things arguably worse.

I think at this point, I’m going to try to revert all the settings in UE5 back to the default. Delete and Re-import all of the materials I’ve used to build the level and just start over…

It should have been such a simple fix. The only thing I did was run “DumpUnbuiltLightInteractions” and rebuild the lighting, and, poof, all of these problems, and now a finished, totally happy project is ruined.

It’s been 3-4 days of troubleshooting, and I’m tired lol.

Thank you for the help :pray:and for your patience. But I’m calling this a loss. I can’t spend any more time correcting it.

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You only get the error about building light, because you have one or more lights in the scene which you have not set to moveable.

By default, the sun, skylight etc are movable. But if you start adding point lights to the scene, they will come in by default as static ( or stationary ). Hence the message. Just make sure they’re moveable.

If you still have fuzzy texture after increasing the pool, it means you just have too many textures loaded. Then the only solution is to use less ( that basically means less materials ).

What GPU do you have, incidentally?

I have an NVIDIA 2070 RTX SUPER

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How much VRAM?

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8 Gigabites VRAM

It’s quite possible to run over that with a lot of high res textures. You might need to just cut down on the number of material variations.

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So I’m still relatively new to Unreal Engine.

By Material Variations do you mean the total amount of unique assets in my level? Like the props?

Or do you mean the materials/material instances themselves?

How do i reduce the number?

By downloading a similar material from Unreal and using that material for all of the materials that are basically the same? Like a wood table, wood floor, wood desk, wood bookshelf, wood fence?

How would i vary the colors and tints with those? Would creating seperate material instances eventually give me the same problem? Or would creating materual instances prevent that fr9m happening again?

Thank you.

It’s textures.

If you have 15 different wood types in your level, unless they are obviously using the same texture, you’ve used at least 15*3=45 textures. ( albedo, normal and roughness etc ).

On disk, at least, a 2k texture is about 8MB, a 4K texture is about 80MB :slight_smile: ( very roughly, it depends on what the texture is )

If those textures are 4K, which they probably are ( because everyone supplies this without thinking ), then that’s much worse than 45 2K textures.

Textures use up your GPU memory.

If you have a lot of different assets from various sources, I know it can be tempting to drop lots of different things in the map, to make it look great. But you can just as easily get great looking levels using only a very small number of assets. You just have to know how to repurpose them in the right way.

This, a pic from a level I’m working on

uses ONE rock and ONE tree.

I know it’s not arch viz, the point is economy of textures.

If you want to just make beautiful renders of apartments, no problem! Just get a GPU with more memory, and off you go.

But if you want to make an end user experience, ( a program people can run on normal PCs ) you have to economize.

Is it starting to make sense yet? :slight_smile:

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