GPU Lightmass disabled

anonymous_user_e3b1e4d3 · February 16, 2021, 9:44am

I’m trying to set up GPU Lightmass baking for my architectural scene. I’ve enabled the GPU Lightmass plugin, along with Ray Tracing and Virtual Texture Support/Virtual Texture Lightmaps. I’ve got the RHX set to Directx 12.
But when I go to Bake > GPU Lightmass, the “Build Lighting” button is greyed out, with the text “SPU Lightmass requires ray tracing support which is disabled”.
Does anyone know why this is, and how I can enable it? I have the most up-to-date (Oct 2020) version of Windows 10, and I have a Nvidia Quadro k620 with the most up-to-date drivers installed. I’m hoping it’s not a graphics card issue and there’s just a checkbox somewhere I’ve missed.
Thanks!

olcaykayihan · February 28, 2021, 5:26pm

Yeah Same issue here

RobinsonUK · March 2, 2021, 2:04pm

I have this issue too. Enabled RT, set RHI to DirectX 12, enabled the plugin (I have a 2070 RTX). Anyone know?

Daluz · March 31, 2021, 4:33pm

Same here RTX 2060

anonymous_user_f9ef059a1 · April 10, 2021, 5:31pm

I had the same issue
I turned on RayTracing in Project settings, restarted, and then it got enabled.

anonymous_user_cf9df459 · May 5, 2021, 6:33pm

the same problem I have , after alot of search I discovered that I must have RTX card or GTX card with DXR support
this may help :-Hardware Ray Tracing Tips and Tricks in Unreal Engine | Unreal Engine 5.1 Documentation

Ayush.Agno3 · August 14, 2021, 10:41am

Hello Everyone,

Had the same Issue,

You Have to turn on “Virtual Texture Support” in project settings, it fixed mine.

Warner_V · August 16, 2021, 10:12am

So you need a couple of things (most mentioned above, but you need all of them):

A Ray Tracing Capable GPU, like an NVIDIA RTX card or latest gen AMD
In plugins, enable the GPU Lightmass plugin
In project settings, set RHI to DX12
In project settings, Enable Virtual Texture Support and Enable Virtual Texture Lightmaps (to show progress bars and enable ‘bake-what-you-see’ baking)
In project settings, Enable Ray Tracing
Restart the engine

Oh, and don’t forget to switch on “Use Irradiance Caching” for inside scenes for the best results

Psygel · August 30, 2021, 7:04pm

I wasn’t able to get this working with my Nvidia GTX 1060, Latest drivers. Can you confirm whether that card is compatible? I’ve been unable to get exactly which cards are not working. Same issue as OP.

Warner_V · August 31, 2021, 7:51am

Hi Psygel,

indeed, the GTX 1060 is not an RTX compatible GPU so GPU Lightmass will not work with that hardware. You might give Luoshuang’s lightmass a try <here>. As far as I understood it doesn’t have the same limitations.

Lorikaluni · September 4, 2021, 2:29am

Hi same Issue. I have a gtx 1070 and i couldn’t find anything, what should i do? Is the gtx 1070 compatible?

anonymous_user_6cf23fb3 · March 18, 2022, 3:49pm

Try disabling the RenderDoc plug-in if you have it enabled.

BizzFate · March 21, 2022, 3:07pm

saved my day!

mz121mz · March 24, 2022, 5:00pm

same issue

clarebearnz1 · May 25, 2022, 7:37am

I had the same issue, turns out it was just my graphics card driver (was 472.39) needed updating.
My current specs are:
myCompSpecs

DS-Waqas · August 6, 2022, 2:43am

Thanks for posting this. I did all this and it worked !

leej231 · January 22, 2023, 3:49pm

Has ue5 stopped you using a gtx card for gpu lightmass it worked fine in 4.27 but can’t enabled it on ue5

AmrSrour · August 16, 2024, 3:08pm

unreal engine gpu lightmass Debug: Visualize not work
in GPU Lightmass settings
anone have the same Issue ?