Problem with lightmaps

RobinThormann

Hi there, 

once again a thread about lightmaps in UE4 (4.14). I cant get rid of the seams:


(rendered with preview, but the seams are also in the production renders)


I created a simple box: 400*400*40. I created a second uv channel for the lightmap, with snapping and spacing.



Here are also the settings:



There is a lightmass importance volume, a directional and sky light (both stationary). Even a 1024 lightmap resolution.

Im simply dont get it.

This floor is 4*12 meters. Should i do for this a single mesh? But this modular pipeline should also work.

Link for the Mesh:
https://www.dropbox.com/s/cptgwyjyj5omxw3/SM_ARCH_Block_400x400x40_a_01.FBX?dl=0

Fwap

I'm probably a bit late and you may have figured this out already, but this issue is due to the way Unreal 4 processes meshes for light bake.
Basically what is happening is your meshes are baked on different threads which results in inconsistent lighting.

And from what i've been able to gather in my searches is, there's not really a way to solve this, except for maybe tweaking some settings, but it's pretty hit or miss, and it's just a constraint with the way lightmass light bakes are done. 

musashidan

Lightmaps are a pain in the arse. If your project can afford it performance wise just whack all the lights to dynamic(moveable) and f**k the lightmaps off altogether!

Obscura

https://forums.unrealengine.com/showthread.php?46269-Modular-Asset-Lighting-Problem

Though setting the static lighting level scale to something low solves this problem for me in the 90% of cases...

Quack!

The solution is to combine those meshes into 1 mesh. It will bake perfectly then.

In the menu: Window > Developer Tools > Merge Actors

This is far from ideal, but is how you have to resolve it in some cases.