Ue5 Level Design

World Partition (UE5 preferred)

For open worlds, use World Partition instead of manual level streaming:

• Data Layers: Organize actors into logical layers (Gameplay, Environment, Audio)
• Runtime Grid: Controls streaming granularity (cell size, loading range)
• One File Per Actor (OFPA): Each actor is its own file -- enables parallel work
• HLODs: Hierarchical LODs for distant rendering
• Minimap: World Partition generates a grid-based minimap for the editor

Sub-levels (classic approach)

For linear or contained levels:

• Use Level Streaming Volumes for automatic loading
• Use ULevelStreamingDynamic for code-driven streaming
• Keep persistent level minimal (only always-loaded actors)

Actor placement

Via Remote Control API

# Spawn an actor at a location
PUT http://localhost:8080/remote/object/call
{
  "objectPath": "/Script/Engine.Default__GameplayStatics",
  "functionName": "BeginDeferredActorSpawnFromClass",
  "parameters": {
    "WorldContextObject": "/Game/Maps/MainLevel.MainLevel",
    "ActorClass": "/Game/Blueprints/BP_Torch.BP_Torch_C",
    "SpawnTransform": {
      "Translation": { "X": 1000, "Y": 500, "Z": 0 },
      "Rotation": { "X": 0, "Y": 0, "Z": 45, "W": 1 },
      "Scale3D": { "X": 1, "Y": 1, "Z": 1 }
    }
  }
}

Via Python bridge

import unreal

editor = unreal.EditorLevelLibrary()

# Spawn from Blueprint class
bp_class = unreal.EditorAssetLibrary.load_blueprint_class("/Game/Blueprints/BP_Torch")
location = unreal.Vector(1000, 500, 0)
rotation = unreal.Rotator(0, 45, 0)
actor = editor.spawn_actor_from_class(bp_class, location, rotation)

# Batch place actors along a path
import math
for i in range(20):
    angle = (i / 20) * 2 * math.pi
    x = math.cos(angle) * 2000
    y = math.sin(angle) * 2000
    loc = unreal.Vector(x, y, 0)
    editor.spawn_actor_from_class(bp_class, loc, unreal.Rotator(0, 0, 0))

Via MCP (ChiR24/Unreal_mcp)

The MCP server provides higher-level actor management:

• Create actors by type (cube, sphere, light, camera, custom Blueprint)
• Set transforms (position, rotation, scale)
• Query and find actors by name or class
• Delete actors
• Manage actor hierarchies

Landscape

Landscape setup

• Component size: 63x63 or 127x127 quads (63 for smaller levels, 127 for large)
• Sections per component: 1x1 (small) or 2x2 (large worlds)
• Scale: Default 100x100x256 (X/Y/Z). For realistic terrain, Z scale of 51200 = ~500m height range
• Material: Use landscape-specific material with layer blending

Landscape layers

import unreal

# Create landscape material layers via Python
landscape = unreal.EditorLevelLibrary.get_all_level_actors_of_class(unreal.Landscape)[0]

# Sculpt operations use the Landscape Editor mode
# For automation, modify heightmap data directly:
# Export: Right-click landscape > Export to file (.r16 or .png)
# Import: Landscape > Import heightmap

Foliage

• Use Procedural Foliage Volume for large-area automatic placement
• Use Foliage Painting for manual detail placement
• Use Nanite for high-poly foliage (UE5.1+): enable Nanite on foliage static meshes
• Grass types: Use Landscape Grass Type for lightweight ground cover (rendered per-component)

Lighting

Light types and when to use them

Lumen (UE5 default GI)

• Lumen Global Illumination: Real-time indirect lighting. No lightmap baking needed.
• Lumen Reflections: Real-time reflections replacing SSR + planar reflections.
• Hardware Ray Tracing: Enable for higher quality (requires RTX GPU).
• Software Ray Tracing: Fallback that works without RTX. Lower quality but no hardware requirement.

Lighting via Remote Control

# Adjust directional light intensity
PUT http://localhost:8080/remote/object/property
{
  "objectPath": "/Game/Maps/MainLevel.MainLevel:PersistentLevel.DirectionalLight_0.LightComponent0",
  "propertyName": "Intensity",
  "propertyValue": { "Intensity": 8.0 }
}

# Change light color
PUT http://localhost:8080/remote/object/property
{
  "objectPath": "/Game/Maps/MainLevel.MainLevel:PersistentLevel.PointLight_0.LightComponent0",
  "propertyName": "LightColor",
  "propertyValue": { "LightColor": { "R": 255, "G": 180, "B": 100, "A": 255 } }
}

Lighting via Python

import unreal

editor = unreal.EditorLevelLibrary()

# Spawn a point light
light = editor.spawn_actor_from_class(
    unreal.PointLight,
    unreal.Vector(500, 0, 300),
    unreal.Rotator(0, 0, 0)
)
light_comp = light.get_component_by_class(unreal.PointLightComponent)
light_comp.set_intensity(5000)
light_comp.set_light_color(unreal.LinearColor(1.0, 0.7, 0.4, 1.0))
light_comp.set_attenuation_radius(1000)

Post-processing

Post Process Volume settings

Key properties to control via Remote Control or Python:

• Exposure: Min/Max EV100, metering mode, exposure compensation
• Bloom: Intensity, threshold, size
• Color grading: Temperature, tint, saturation, contrast, gamma, gain (per shadows/midtones/highlights)
• Ambient occlusion: Intensity, radius, bias
• Depth of field: Focal distance, aperture (f-stop), near/far transition
• Motion blur: Amount, max velocity
• Tone mapping: Film slope, toe, shoulder

Environment

• Sky Atmosphere: Realistic atmospheric scattering. One per level.
• Volumetric Clouds: GPU-driven cloud rendering. Configure coverage, density, shape.
• Exponential Height Fog: Distance fog with directional inscattering.
• Ultra Dynamic Sky (marketplace): Popular all-in-one sky/weather solution.

Performance guidelines

• Draw calls: Keep under 2000 for 60fps. Use instanced static meshes for repeated geometry.
• Nanite: Enable for complex static meshes. Automatic LOD with virtualized geometry.
• Virtual Shadow Maps: UE5 default. Handles large worlds well but costs VRAM.
• Occlusion: Use precomputed visibility volumes in indoor areas.
• LODs: Auto-generate via mesh editor for non-Nanite meshes.
• Texture streaming: Use virtual textures for large landscapes.
• Profiling: Use stat unit, stat gpu, stat scenerendering console commands. ProfileGPU (Ctrl+Shift+,) for per-pass timings.

Collision and navigation

• Collision: Use simple collision (boxes, spheres, capsules) over complex collision where possible
• NavMesh: Place a NavMeshBoundsVolume to enable AI pathfinding. Configure agent radius/height.
• Navigation modifiers: Use NavModifierVolume to mark areas (avoid, prefer, custom)
• RecastNavMesh: Default navmesh system. Configure cell size, agent parameters.

File and asset conventions

/Game/
  Maps/              -- Level files
  Blueprints/        -- Blueprint actors
  Environment/
    Meshes/          -- Static meshes
    Materials/       -- Material instances
    Textures/        -- Texture assets
  Lighting/
    LightProfiles/   -- IES profiles
    HDRIs/           -- Sky/environment maps
  FX/                -- Niagara particle systems
  Audio/
    Ambient/         -- Environmental audio
    SFX/             -- Sound effects

Workflow

1. Block out: Place BSP brushes or simple meshes to define spaces
2. Gameplay test: Verify scale, sightlines, flow with placeholder actors
3. Art pass: Replace blockout with final meshes and materials
4. Lighting pass: Set up lights, sky, post-processing
5. Polish: Foliage, decals, particles, audio
6. Optimize: Profile, add LODs, configure streaming, set culling distances