Gpu Light Mass Error

Development Rendering
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1

Hello Everyone ,

I’m using UE 5.5 and whenever i start baking the light with gpu lightmass it crashes .
it gives me this error always .

Assertion failed: GeometrySegmentIndex == RayTracingMeshCommand.GeometrySegmentIndex [File:D:\build++UE5\Sync\Engine\Plugins\Experimental\GPULightmass\Source\GPULightmass\Private\Scene\Scene.h] [Line: 50]

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2

Hey Souls-Taker! Let me help you with this. I discovered that this type of error usually happens for several reasons; I am providing you with the sources.

Check your meshes:

  • Make sure all meshes in your scene have “Support Ray Tracing” enabled.
  • Try temporarily removing recently imported meshes and test again.

https://www.reddit.com/r/unrealengine/comments/1fjfgu6/im_desperately_trying_to_get_lighting_to_function/

Clean and validate Swarm Agent cache:

-Open Swarm Agent, go to the Cache menu, and choose Clean and Validate.

https://www.reddit.com/r/unrealengine/comments/14xi3a4/lightmass_crashed_error_solved/

If you’re still facing challenges or have new questions, feel free to share.

3

Thank you for reply , I did check my geometry and all set to ray tracing .
and I did clear the cache of swarm but I believe it has nothing to do since it’s gpu baking .

Unfortunately , the problem still persists
.

4

Hello Everyone , please anyone has an idea how to solve this .
Project was imported from 3ds max using unreal datasmith .