Is there a way to make small meshes work with lumen?

To my understanding, the problem I’m having here: Photo is due to the meshes being too small, and if I increase the size, it fixes them.

Seeing how the coins are meant to be small, I don’t want to do that. Any workarounds?

What is the problem exactly?

Hey there @Estrange! Since Lumen uses RT, small objects can easily be overlooked/underlit. So there’s one primary setting that helps out with smaller objects, but not sure how small it will help for. Lumen scene detail can help with smaller items, but be warned the GPU cost is exponential so incredibly high values will tank your FPS. Try it out and let me know if it helps!


I was just curious, but it’s working fine for me:

If you want, you can try with that static mesh (it’s 1cm radius!):
Cylinder_10BA5211.FBX (21.1 KB)

EDIT: Oh, my fault! I was using ray tracing shadows (you can too), but when only virtual shadow maps enabled, it’s also visible, even if less noticeably.

Sorry to resurrect an old thread, but is there a way to accomplish this on a per-mesh basis? Increasing the Lumen Scene Detail value seems to work, but is global and certainly impacts performance. Would be nice to be able to adjust this for only the meshes that are critical.

Try to increase the build scale, and modify the mesh scale to restore normal size

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I don’t know of a workaround for individual objects unfortunately, likely not easily without source edits as Lumen treats all objects with the same rules based on it’s size. Though if it is bounds based, Felsto’s suggestion might work

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Unless you have some specific need it’s really not a good idea to try to force Lumen to include small objects. They will be picked up by screen traces, which is good enough in most cases.

You can set the object to be tagged as ‘emissive’ in the editor, which just makes UE cull it much further out than normal, but that should be used very selectively- you’re essentially telling it to shoulder a memory cost outside of what lumen naturally wants to spend, and it’s only really meant for emissive objects that are actually contributing lighting to the scene.