World Manager

Cache Biomes, Spawn HLODs, and Handle Runtime Generation

BP_WorldManager — Collects and maintains the biome cache, manages runtime generation, and spawns HLOD content for efficient streaming and performance. It also performs post-generation level cleanup, removing temporary data and keeping the world state tidy after setup.

RuletheWorld

How To

Manage Runtime Generation in regular level

Runtime Generation was added specifically to address long load times when using Nanite foliage. Instead of loading everything up front, it spawns meshes on the fly around the player as needed and despawns them when the player moves far away. This also lets you use regular levels instead of World Partition. In fact, it often works better in regular levels.

Disclaimer:

This is an advanced workflow. Use it only if you have a clear reason to do so.

Step 1

Enable Runtime Generation on at least one Biome or SubBiome. You can mix runtime and non-runtime biomes in the same level. Press Spawn, then wait for PCG generation to finish (bottom-right corner → PCG Tasks). BP_WorldManager will be spawned automatically. You won’t see any changes in the level immediately.

Step 2

After generation completes, select BP_WorldManager and press Runtime Cache → Build Once the cache is built, Runtime Generation should start. If it doesn’t, press Runtime Generation → Resume You can pause it at any time with Pause. Note: Runtime Generation will also stop if the cache is cleared.

Step 3

Avoid using the Cinematic Quality Preset in Biome settings together with Runtime Generation — it defeats the purpose of using it. Nanite foliage can quickly become a performance bottleneck, which is why we added fake HLODs. To use them with Runtime Generation, select BP_WorldManager and press HLOD Simulation → Spawn

Step 4

Empty PCG Partition Grid Actors spawned by biomes can cause performance spikes. To reduce them significantly, clean them up after the cache is built. Press World Cleanup → Cleanup Biomes — this should despawn them because they’re no longer needed (all biome data is stored in the cache). After the biomes have been despawned, run Tools → PCG Framework → Delete → Unused PCG Partition Grid Actors from the editor’s menu.

Useful tip

When you change a Biome, you need to respawn it and rebuild the cache to see the update, which can be inconvenient. A practical workaround is to do your editing in a level without Runtime Generation, then enable Runtime Generation only once everything is finalized and you’re ready to ship.

How To

Manage Runtime Generation in World Partition Levels

Although World Partition can cause performance drops and spikes during chunk loading/unloading, some projects still rely on it for various reasons.

                
                Disclaimer:
              
                BP_WorldManager does not work in packaged projects on World Partition levels. It may still spawn automatically, but you can ignore it or use it while editing the world. To use Runtime Generation on World Partition levels, the entire workflow must be done manually before shipping.

                Step 1
              
                Repeat Step 1 from the How To Manage Runtime Generation section above.

                Step 2
              
                Navigate to Content → EasyBiomes → PCG → Graph → Functions where you will find PCG_RuntimeCache, PCG_RuntimeSpawner, and PCG_HLODSpawner. Dublicate them and add "_WP" suffix.

                Step 3
              
                Open PCG_RuntimeSpawner_WP and add a Get PCG Component Data node.

                Set the following settings:

                ●  Actor Selector Settings → Must Overlap Self

                ●  Actor Selector Settings → Actor Selection → By Tag

                ●  Actor Selector Settings → Actor Selection Tag → Cache

                Create following expected Pins:

                ●  Data Retrieval Settings → Expected Pins → +

                ●  Index [0] → RTree

                ●  Index [1] → RActor

                ●  Index [2] → RMesh

                ●  Index [3] → RHLOD

                Step 4
              
                Rewire all connections from the Get Actor Data node to the matching outputs of the Get PCG Component Data node. Copy this Node, save graph and clode.

                Step 5
              
                Open PCG_HLODSpawner_WP and paste Get PCG Component Data node.

                Rewire RHLOD connection from the Get Actor Data node to the RHLOD output of the Get PCG Component Data node. Save and close.

                Step 6
              
                Place PCG_RuntimeCache_WP, PCG_HLODSpawner_WP and PCG_RuntimeSpawner_WP in the level and scale them so they fully cover your Landscape.

                Set the following settings:

                PCG_RuntimeCache:

                ●  PCG Component → Settings → Generation Trigger → Generate on Demand

                ●  PCG Component → Settings → Is Partitioned → Enabled

                ●  PCG Component → Editing Settings → Regenerate PCG Volume in Editor → Disabled

                ●  Actor → Advanced → Tags → + → Cache

                PCG_RuntimeSpawner:

                ●  PCG Component → Settings → Generation Trigger → Generate at Runtime

                ●  PCG Component → Settings → Is Partitioned → Enabled

                ●  PCG Component → Editing Settings → Regenerate PCG Volume in Editor → Disabled

                PCG_HLODSpawner:

                ●  PCG Component → Settings → Generation Trigger → Generate on Demand

                ●  PCG Component → Settings → Is Partitioned → Enabled

                ●  PCG Component → Editing Settings → Regenerate PCG Volume in Editor → Disabled

                Step 7
              
                Select PCG_RuntimeCache_WP and press Generate, then wait until it finishes.

                Runtime Generation should start working immediately.

                If you need HLODs, select PCG_HLODSpawner_WP and press Generate

                After that, build HLODs, then clear PCG_HLODSpawner_WP.

                Step 8
              
                Repeat Step 4 from the How To Manage Runtime Generation section above, except you need to manually select runtime biomes and press Remove

Runtime Cache

Build

Generates or updates cached biome data.

Clear

Removes all cached biome data.

Runtime Generation

Pause

Temporarily stops runtime biome generation.

Resume

Runs Runtime Generation.

HLOD Simulation

Remove

Removes HLOD or Proxie Meshes.

Spawn

Generates HLOD or Proxie Meshes.

World Cleanup

Cleanup Cached Biomes

Clears cached biome instances from the world to avoid empty chunks loads/unloads. Helps with lowering spikes in streamed levels. Remove all unused PCG partition grid actors after this. Tools -> PCG Framework -> Delete -> Unused PCG Partition Grid Actors.