Hello,
I am making an open world game and I am absolutely struggling with HLODs and World Partition Streaming. There seems to be very little information online on how to set this up or how to fine tune it. I’ve been struggling with this for 9 months and still can’t work it out.
Could you please point me to resources on how to configure HLODS and world partition streaming and optimise it for performance. Alternatively can you point out anything I might have missed or be unaware of that would cause the below problems.
I currently have a 1000 sq km landscape surrounded by infinite ocean and smaller island landscapes but HLODS and the streaming just does not work. It is completely unplayable as a game and crashes or freezes within an hour every time. The problems get more frequent the more I add to the level.
These are the current problems and questions I have from most severe to least severe:
- HLODS for my landscapes do not work at all. My level was made in ue4 and then converted to ue5 World Partition. It seems to load a large world partition region around the player (likely the 120000 I defined in WP settings) and in the distance no land is displayed so cities float in the distance. I can’t tell if the HLODs are even working for cities, parts of the cities are missing until I get close so probably no. I’ve reconfigured and rebuilt HLODs so many times and no HLODs will display no matter what I do. LODs appear to be working fine.
- When I move across the level I get ‘slow world partition streaming’ and it turns into a slideshow while the next area loads, it gets worse the more regions I cross until it crashes after about 20min to an hour of play. I don’t even have that many assets. I can’t build anything like the matrix city because it would be a slide show and loading screen.
- Every time I move around my map I get shaders compiling and other things building. How do I just build them so I can play the game as it would work? Since 5.1 everything wants to build when playing the game.
- The game constantly throws up errors because the streaming doesn’t seem to load/unload blueprints correctly. I get errors for uninitialised objects that would normally work and the blueprints break in random ways. Every blueprint is affected, from AI to procedural buildings. The errors look like this: Blueprint Runtime Error: “Accessed None trying to read property Current Volume”. Node: Branch Graph: Apply Current / Local Weather Function: Apply Current / Local Weather Blueprint: Ultra_Dynamic_Weather - This example is from Ultra Dynamic Weather which should be bug-free. I’ve managed to fix some of my own blueprints with isValid checks but I feel there must be a streaming/blueprint setting I missed.
- The game constantly crashes either because of the above issue or because it runs out of video memory eventually. It seems like streaming does not unload things before it runs out of memory and has some kind of memory leak.
- The foliage loads in as large regions, very slowly and only if you are close and stare at it for a while and looks absolutely terrible because it’s all square edges. I assume HLODs would fix this if they were working? They should look like billboard LODs stretching to the horizon or fading out.
- Only recently I learnt that streaming doesn’t work in the editor window and only in standalone so I’m not sure how I missed that. But I’m still not clear on what exactly the difference is between the two. Also do HLODs work in the editor window or only in standalone?
- I don’t understand why certain islands/buildings persist in the editor/game and are visible from far away even when the region is unloaded but others have to be manually loaded or loaded by streaming. What is controlling this? Is it a setting? Does it mean HLODs are working for these specific assets?
Any help would be appreciated. I believe I’ve watched every major guide and read all the hlod/WP docs out there but I still am struggling to understand if I missed something, if it’s the ue4 to ue5 level conversion that didn’t work correctly, or if UE5 is hlods/streaming is just not very good right now.