Adjacent planes are lit differently

anonymous_user_389b5b1d · May 8, 2014, 10:01pm

I noticed when I put flat surfaces adjacent to eachother and built the lighting that the lighting is different for each object. Even when I move the objects the cached lighting has the same problem. I’ve used both the planes and cubes that come with the default content and got similar results.

Any idea what’s going on and how to fix it?

Michael_Boeni · May 9, 2014, 1:22pm

That could be quite a few things - have you tested this in a fresh scene from scratch or have you used a template and changed that?. I assume you have copied the meshes (i.e. they have the same lightmap resolutions)?

What type of lights are you using?

Cheers,
Michael

anonymous_user_389b5b1d · May 9, 2014, 1:56pm

This scene is from starting a blank template with the starter content checked (the one with the table and two chairs). The version I’m using is 4.1 from the source. I’m using copies of the same static mesh right from the Shapes folder. The lightmap resolution for each mesh was 32 I believe, but I did try changing it and it didn’t seem to make much difference.

Edit:
I just checked and it uses a directional light. There’s also a sphere reflection capture and sky sphere.

Thanks

Michael_Boeni · May 9, 2014, 2:05pm

Okay a few thoughts:

I assume you are baking at preview level (standard setting). Do you get the same issues with production level lighting?
Does changing the directional light properties (angles / intensity) resolve the issue?
Try to rule out material properties and reflections as potential sources (e.g. use a neutral grey material and kill the reflection sphere). If you solve it this way, try to reintroduce the components as you need them

Let me know how it goes

Cheers,
Michael

Michael_Boeni · May 9, 2014, 2:06pm

Oh, and do check the lightmap UVs! Do you get any lighting-related error/log entry?

anonymous_user_389b5b1d · May 9, 2014, 4:32pm

I’ve been using the production settings but they don’t seem to make a difference. I tried removing the reflection sphere and still got the error. Changing the material also doesn’t make a difference.

The problem is most apparent when the lighting is purely indirect lighting. When the light is facing the surface it’s much less noticeable. It seems like each mesh is getting an averaged color for the indirect lighting or something like that. Where there should be a gradient each mesh is colored distinctly it’s own color.

It’s pretty easy to set up to test, if it’s happening to anyone else. I’m just duplicating (alt+moving) a Shape_Plane (in the Shapes folder from the default content of a blank project) to make a wall. I turned them away from the light source so that they’re only getting indirect lighting when I build.

bigzer · May 9, 2014, 4:50pm

Have you tried with adjacent boxes (closed meshes)? I think ue4 has issues with meshes that are “open”.

anonymous_user_389b5b1d · May 9, 2014, 5:05pm

Yeah I’ve tried boxes as well and they produce a similar result.

TomShannon · May 9, 2014, 6:52pm

This is an ongoing issue and is currently being worked on. however, there’s no timeline for a solution:

Sorry for the bad news

anonymous_user_389b5b1d · May 9, 2014, 7:27pm

Thank you for the response. Does anyone know if there are any work-arounds to this? I know lpv is being added, maybe dynamic lighting would work better? Is there any way to bake the lighting externally currently?

Michael_Boeni · May 9, 2014, 9:39pm

You could try dynamic lighting. I’ve had a similar issue btw with indirect lighting for decals which I fixed with a workaround, but haven’t been able to reproduce your issue here :o

bigzer · May 10, 2014, 4:31am

That sux, we’ve got this issue on all our maps, not pretty at all and fully dynamic lights would be very heavy for our maps.

anonymous_user_698516071 · May 19, 2014, 7:01am

Hmm, Iam having the same issue… No matter what lightmass-settings I use :_(

Are there any updates on the work of a fix on that?
Or do you have any ideas for a good workaround? DynamicLighting would be too extensive in my map and I do not really want to break up the geometry by adding pillars and whatnot that would hide the seams…

anonymous_user_389b5b1d · May 19, 2014, 4:45pm

So far the solution I found that works is to not use lightmass at all and use LPV. I don’t have the issue at all with LPV and it works out well for more procedural setups (which I’d like for my own content). As of now lightmass seems completely broken and I’m not sure I would trust lighting with it for the time being. The performance for LPV isn’t too bad.

n00854180t · June 16, 2014, 6:20pm

LPV doesn’t work with the Rift plugin, though, sadly. For those making VR games this problem is going to get annoying fast.

Obihb · June 19, 2014, 7:51am

The way I get past this problem is to set the “Static Lighting Level Scale” setting inside Lightmass, to a smaller number. The default is “1” and I take it down as far as "0.3 or maybe even “0.2”. Doing this can impact build times quite a lot since you’re basically firing way more photons into the scene but the result is more accurate bounced light.

So, for testing purpose, I keep it at “1” but for quality builds I use the smaller values.

n00854180t · June 19, 2014, 8:48pm

Oh dang, nice. Thanks much for this, going to try it out later tonight and see if it fixes the ugly light bleed on static meshes.

Being used to compile times, I’m not too bothered by a long lighting build time.

ssandweiss · February 8, 2015, 10:32pm

Was just curious did a solution ever get presented for this problem?

I was able to do a combo of adjusting the static lighting level scale down to .2 or .3, and not using a solid texture. Seems like the simpler the material on the static mesh, the more prominent it becomes.