Overview

BP_WorldManager Blueprint Class icon
Runtime + streaming manager

World Manager

Cache biomes, handle Runtime Generation, spawn HLODs, and clean up generated world data

BP_WorldManager collects and maintains the biome cache, manages Runtime Generation, and spawns HLOD content for more efficient streaming and performance. It also provides cleanup tools for removing temporary biome data after the cache has been built.

Runtime Cache Runtime Generation HLOD Simulation World Cleanup
EasyBiomes forest environment managed by BP_WorldManager
BP_WorldManager · runtime biome management
Advanced workflow

Runtime Generation in a Regular Level

Use Runtime Generation when you need to avoid loading all Nanite foliage up front. It spawns meshes around the player as needed and despawns them again at distance.

Advanced workflow. Use Runtime Generation only when you have a clear reason to. The documentation specifically presents it as a solution for long load times caused by heavy Nanite foliage.
01

Enable Runtime Generation on a Biome or SubBiome

Enable Runtime Generation on at least one Biome or SubBiome. Runtime and non-runtime biomes can be mixed in the same level.

Press Spawn, then wait for PCG generation to finish. You can monitor progress in the bottom-right PCG Tasks indicator.

BP_WorldManager is spawned automatically. You should not expect an immediate visual change in the level.

02

Build the Runtime Cache

After PCG generation has finished, select BP_WorldManager and press Runtime Cache → Build.

Runtime Generation should start once the cache is ready. If it does not, press Runtime Generation → Resume. Use Pause whenever you need to stop it temporarily.

Cache dependency. Runtime Generation also stops when the Runtime Cache is cleared.
03

Use HLOD Simulation when needed

Avoid combining Runtime Generation with the Cinematic Biome Quality preset. The source documentation notes that this defeats the purpose of the runtime workflow because Nanite foliage can become a performance bottleneck.

To use the built-in fake HLOD system, select BP_WorldManager and press HLOD Simulation → Spawn.

04

Clean up empty PCG Partition Grid Actors

After the Runtime Cache has been built, press World Cleanup → Cleanup Cached Biomes. The biome actors are no longer needed because their generated data is stored in the cache.

Then use the Unreal Editor menu:

Tools → PCG Framework → Delete → Unused PCG Partition Grid Actors

This cleanup is intended to reduce spikes caused by empty PCG Partition Grid Actors.

Editing tip. Changing a Biome requires you to respawn it and rebuild the Runtime Cache before the update appears. A practical workflow is to do most editing in a level without Runtime Generation, then enable Runtime Generation once the environment is finalized.
Manual World Partition workflow

Runtime Generation in World Partition

World Partition requires a different, manual setup. The packaged-project limitation below is important.

Packaged-project limitation. According to the current EasyBiomes documentation, BP_WorldManager does not work in packaged projects on World Partition levels. It may still spawn automatically, but the Runtime Generation workflow must be prepared manually before shipping.
01

Enable Runtime Generation on the biome

Repeat Step 1 from the regular-level workflow above: enable Runtime Generation on at least one Biome or SubBiome, press Spawn, and wait for PCG generation to finish.

02

Duplicate the runtime PCG graphs

Navigate to:

Content → EasyBiomes → PCG → Graph → Functions

Duplicate PCG_RuntimeCache, PCG_RuntimeSpawner, and PCG_HLODSpawner. Add the _WP suffix to each duplicate.

03

Modify PCG_RuntimeSpawner_WP

Open PCG_RuntimeSpawner_WP and add a Get PCG Component Data node.

Actor Selector Settings
Must Overlap Self

Enable this option.

Actor Selection

Set to By Tag.

Actor Selection Tag

Set to Cache.

Expected Pins
Index [0]

RTree

Index [1]

RActor

Index [2]

RMesh

Index [3]

RHLOD

04

Replace the Get Actor Data connections

Reconnect every output that previously came from Get Actor Data to the matching output of the new Get PCG Component Data node.

Copy this node, save the graph, and close it.

05

Modify PCG_HLODSpawner_WP

Open PCG_HLODSpawner_WP and paste the Get PCG Component Data node you copied.

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

06

Place and configure the three World Partition actors

Place PCG_RuntimeCache_WP, PCG_HLODSpawner_WP, and PCG_RuntimeSpawner_WP in the level. Scale them so they fully cover the Landscape.

PCG_RuntimeCache_WP
Generation Trigger

Generate on Demand

Is Partitioned

Enabled

Regenerate PCG Volume in Editor

Disabled

Actor → Advanced → Tags

Add the tag Cache.

PCG_RuntimeSpawner_WP
Generation Trigger

Generate at Runtime

Is Partitioned

Enabled

Regenerate PCG Volume in Editor

Disabled

PCG_HLODSpawner_WP
Generation Trigger

Generate on Demand

Is Partitioned

Enabled

Regenerate PCG Volume in Editor

Disabled

07

Generate the Runtime Cache and optional HLODs

Select PCG_RuntimeCache_WP and press Generate. Wait for generation to finish. Runtime Generation should then begin automatically.

If you need HLODs, select PCG_HLODSpawner_WP and press Generate. Build the HLODs, then clear PCG_HLODSpawner_WP.

08

Remove the runtime biome actors manually

Repeat the cleanup process from Step 4 of the regular-level workflow, but manually select the runtime biomes and press Remove.

Actor reference

Details Reference

BP_WorldManager exposes four groups of actions: cache management, Runtime Generation controls, HLOD simulation, and world cleanup.

BP_WorldManager Details panel in Unreal Engine
Runtime Cache
Build Button
Generates the Runtime Cache or updates the existing cached biome data.
Clear Button
Removes all cached biome data. Clearing the cache also stops Runtime Generation.
Runtime Generation
Pause Button
Temporarily stops Runtime Generation.
Resume Button
Starts or resumes Runtime Generation.
HLOD Simulation
Remove Button
Removes generated HLOD or proxy meshes.
Spawn Button
Generates HLOD or proxy meshes.
World Cleanup
Cleanup Cached Biomes Button
Clears cached biome instances from the world after their data has been stored in the Runtime Cache. This is intended to reduce empty chunk load/unload work and lower streaming spikes. After cleanup, remove unused PCG Partition Grid Actors through Tools → PCG Framework → Delete → Unused PCG Partition Grid Actors.