How to optimize a very large imported heightmap landscape for streaming?

Hey guys. I’m working my way through the documentation and watching videos, but I’m having some trouble finding the right settings for a heightmap I’m importing. The map itself is large. By large I mean, it will take the player 1 hour to cross the map vertically and 45-50 mins to cross horizontally. in real time. So its large. About 135 square miles based in UE5 standards.

So my problem is trying to find the correct settings during import. I’m in a world partition enabled level, and the last time I tried to load, UE5 crashed saying it ran out of memory. So I’m not exactly sure what settings to use as far as section, components, grid sizes, etc.. or if there are other settings that I need to tweak.

The game itself is more stylized (think fortnite) and not photorealistic so higher quality isn’t the upmost of importance. I’m looking for better performance for streaming different parts of the level in.

Any help would be greatly appreciated, even if its just pointing me to a good tutorial, video or article.

Thanks for reading!

Hi @Goldenfiz!

Yeah, running out of memory is a very common issue with large open worlds, and not always the easiest to diagnose. Is your level empty other than the landscape?

Firstly, I would check your HLODs and make sure your landscapes are excluded from any HLOD layers, as they are not supported and are a common cause of memory crashes.

Here’s some documentation on World Partition HLODs and how to use them properly:
https://dev.epicgames.com/documentation/en-us/unreal-engine/world-partition---hierarchical-level-of-detail-in-unreal-engine?application_version=5.1