Lightmap Issue


when i use a grass mesh and place maybe 1000+ meshes, lightmap says it´s to big and render time exceeded.
Anybody can tell me why? The Kite Demo is also full of grass meshes and there it work fine.

Thanks a lot for your help.

Best regards


Have you tried lowering the lightmap resolution in the Foliage tool settings for that particular grass mesh? Anything above 8 is probably going to throw a warning like this.

As for the Kite Demo content this content was originally built with the intent of being used with Dynamic Lighting. The Kite Demo has also been optimized by using cull distances for the grass mesh so that it’s not all rendered far out on the screen as well. It’s only around the player within a few or more meters out.

You may want to also try looking at profiling your scene and seeing where the bottle necks are happening. You can read more about that in our documentation here: Testing and Optimizing Your Content | Unreal Engine 5.2 Documentation

Hello Tim,

thank you so far that helps to lower the Lightmap resolution.
But there is another issue which occured:

whem i´m using static Meshes and drag them to the edit point the loading time exceeds.
This happens with Boulder, Tree and Rock meshes which size is between 2-6 Megabyte. They are all from the Kite Demo.
After reinstalling UE the meshes loads and freeze in UE most between 70-98%. Nothing works and i´ve to shut down UE via Task Manager.

Thanks a lot for your answers.

Kite demo assets are not just the static meshes but the materials as well which are 8k resolution. When you load these for the first time this has to be written to the DerivedDataCache so that they can open more quickly next time. The initial loads of any of these assets will take some time, mostly dependent upon your systems specs. Even on our machines here in Support, which are high-end, it can take a few minutes or more depending for the assets to open the first time.

Thanks a lot for your help, Tim.

Which values are the best for the cull distance in a 15x15quad level?
I cant manage the right amount of the instances cause when i have 61k grass mehes and turn down lightning value
it freezes while rendering. Nothing works and this is for hours.