Why im getting this problem " invalid argument "
Have you tried with the CPU lightmass too? So, if it still happens, it should be an unwrapping issue.
Maybe they are two sided materials?
Maybe this helps watch?v=GJPHKiShliM&t=861s
I installed this but when lightmass starts it gives me “Invalid device symbol”, is NVIDIA 770 no longer supported? I have been using Unreal Engine 4.19 using GPU lightmass without problems…
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Hey all,
I cant get the GPU lightmass to build with anything but default world settings. I set the indirect lighting bounces to 20 but it will only ever do 3. This happened after i split the level into two separate levels to use level streaming. It was working well before I did this. Has anyone had this problem and know a fix? See the image below. The radiosity pass used to do 20 passes now it will only ever do 3.
Also i’m building the light using this command to save memory if this might be the cause?
You can use command line to launch the editor and bake lighting to save GPU resources for GPULightmass, especially video memory.
- Engine/Binaries/Win64/UE4Editor-Cmd.exe “path o\your\project\yourproject.uproject” -run=resavepackages -buildlighting -allowcommandletrendering -map=/Game/Maps/MyMap.umap
- Remember to replace Content with Game in the umap path
Does GPU lightmass support bouncing/indirect lightning from light sources other than Skylight/Directional light? I can’t get light bounced from areas directly lit by Spot/Point/Area light sources, Lightning view mode shows only direct lightning. Using 4.25, I think I had problem in 4.24.3 as well.
EDIT: I think I might have a clue - disabling Inverse Falloff from Spotlight seems to disable bouncing/indirect lightning (or possibly make it so weak you can’t see in Lightning viewport mode). Could anyone verify it?
Hello! my first time writing in this beatiful place in the world. Thank you guys for all this time working on this proyect!
I`m working on 4.25 and got this really bad quality shadows but only from spotlights… all the assests are with big resolution maps, and my lightmass congif is good i think…
VisibilityNormalOffsetSampleRadiusScale=.5
[DevOptions.StaticLightingProductionQuality]
NumShadowRaysScale=32
NumPenumbraShadowRaysScale=64
[DevOptions.GPULightmass]
NumPrimaryGISamples=128
NumSecondaryGISamples=64
FireflyClampingThreshold=10000.0
any ideas?
For the Realtime Lightmap Progross, you have to enable Virtual Texturing in Project Settings. It looks Correct after Lightbuild, you have a red floor and the Color is bouncing on to the walls.
Your table’s lightmap resolution is too low! /you can see the size of the texels!/
The same with your scene too:
Your floor’s lightmap resolution is too low! /you can see the size of the texels!/
Your lightmap UVs is not ideal: too many seamscuts where you see the black pathes! Those are the edges of the given lightmap uv!
You should try to create your own lightmap, keeping the full fabric (visible part) as one island!
Since it creates the same volumetric samples in the world I’m assuming it works the same: you’ll need to turn on the use of static lighting on those movable meshes and tune the sample placement under lightmass (Volumetric Lightmap Detail Cell size…)!
Thank you Makigirl… the lightmap resolutions are very hight, but yes i need more! i dont undersatand why i used to work with that definition and it was fine, and now is not.
but now im working with all the walls exploded, each side a different object, and 1024 lightmaps… and is really better, but not good enough.
i will continue testing…
thank you!
hello … why I’m getting this problem and the GPU lightmass crash and it stop the light building …!!
I’m using the 4.24.3 and 4.25.1 version and its the same problem :eek::mad:
ps: I copied the engine file to the installation directory file.
anyone have a proper installation guide I’ll be thankful … 
Try to clean and then validate the cache in swarm agent!
is 4.25.1 supported? i accidentally updated to 4.25.1 and now every time i try to bake lighting with gpu lightmass it throws an error after completing building BVH (the error says invalid argument)
i did that but the problem still there look what it says on the swarm agent log
" GPULightmass Kernel: Line 106: cudaCheckError: invalid argument"