game-development-unreal-engine-unreal-world-builder

World Partition cell size should match your streaming budget and content density: 64m cells for dense urban areas, 128m for open terrain, and 256m or more for sparse desert or ocean. Configure the runtime hash grid before populating the world, since changing it later requires a full level re-save.

Use a PCG graph with a surface sampler, biome mask filtering, exclusion zones for roads and water, Poisson disk distribution, and weighted Nanite-enabled mesh assignment. Pre-bake PCG output for areas larger than 1km² to keep streaming compatible and avoid runtime generation hitches.

HLOD should be built for all areas visible beyond 500m camera distance, but Nanite-enabled meshes are excluded because Nanite handles its own LOD. HLOD also does not support skeletal meshes, so it applies only to static mesh actors in the coverage area.

Yes, enabling One File Per Actor (OFPA) on World Partition levels lets multiple users check out individual actors from source control instead of the entire level file. Large levels generate thousands of files, so file count budgets should be established.

Streaming hitches usually come from oversized cells loading too much content at once, a streaming source range the player can outrun at sprint speed, or runtime PCG generation in large zones. Profile with Unreal Insights and validate that no hitch exceeds 16ms at maximum movement speed.

A maximum of 4 active Landscape layers should be visible in a single region, since more layers cause material permutation explosions. Enable Runtime Virtual Texturing on any Landscape material with more than 2 layers to eliminate per-pixel layer blending cost.