Can anyone recommend videos or posts that explain how to set up HLOD layers for world partition projects? The documentation for this feature is pretty bad. I’m hoping to create an HLOD system that will reduce the video card memory and draw calls that my city model project uses. But at the moment, I can’t seem to get the HLOD layers to do anything at all. I’d love to hear how people decide how many layers to use and the best way to set up distances and cell sizes. And, I’m still confused by why there’s an HLOD layer in the project settings and in the actors. I’ve also read that there are CVars that affect how HLODs stream… It would be great if this information was all in one place.
Hello ! @DonaldNewlands
HLODs need to be built and have their own Data layers. You can then create multiple HLODs based on foliage, buildings etc… This is why there are HLODs settings everywhere. If it isn’t doing anything like in your project, make sure the World Partition and streaming is enable, virtual texture set and every tools working properly. I feel that if you use these tools you should all use them since they are interconnected.
The HLODs layer in the project settings and in the actors are made so you can assign it to data layers. In UE 5.1 you can make One file multiple actors or Package Meshes etc… that can then be attributed to a layer. With the HLODs settings in the data layers you can change things like Merge meshes to save memory indeed. (You need to create HLODs instances and build them like you would build lighting and then data layers + assign)
The best video in my opinion to understand all about the system (39:00 HLODS) :
Building Open Worlds in Unreal Engine 5 | Unreal Fest 2022 - YouTube
To best to set your HLODs distance and grid properly, in my opinion, is to use the same grid size as the Landscape and the Runtime Grid created. You can activate the Grid of your landscape and then activate the grid of the Runtime grid (Dont forget to name it and assign to the assets/player + make sure assets are set to Spatially Loaded = works properly) and superpose them until they align. This will give you a feel that the data layers load/unloaded at the same time of your landscape tiles, foliages, actors and buildings like in your case.
Hope I understood well and try to pass my information as best possible,
if you have more specific question about World Creation I will be glad to answer !
-Max, Indie Dev 
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