Procedural World Building

Prerequisites

This lesson uses 6 skills from the World Building cluster. Familiarity with the Unreal Editor viewport is helpful but not required.

What You'll Build

A large outdoor landscape with sculpted hills and valleys, grass and trees growing on appropriate slopes, a river winding through a valley, dynamic clouds and atmospheric fog, procedurally scattered rocks and debris, and streaming enabled for efficient loading. This is the foundation workflow for open-world games, architectural visualization, and environmental cinematics.

Step-by-Step Workflow

Step 1: Create the terrain

/skill landscape-management

Tell Claude:

"Create a Landscape with 4 components, 127 quads per section. Sculpt rolling hills in the center with a valley running east to west. The terrain should feel like temperate grassland."

What to expect: Claude creates a Landscape actor and applies heightmap sculpting to form gentle hills with a natural-looking valley. The terrain material will be set up with layer blending for grass and dirt based on slope angle.

Connection to next step: With terrain established, foliage needs appropriate surfaces to grow on.

Step 2: Add vegetation

/skill foliage-placement

Tell Claude:

"Paint grass across the flat and gentle slopes. Add clusters of deciduous trees on the hillsides but not in the valley floor. Use Landscape Grass Type for the grass layer so it is procedural."

What to expect: Claude configures foliage meshes with density, scale variation, and slope constraints. Grass appears across flatlands using the Landscape Grass Type system (procedural, no manual painting needed). Trees are placed on hillsides with natural clustering and randomized rotation.

Step 3: Add a river

/skill water-system

Tell Claude:

"Create a river that follows the valley from east to west. The river should be about 8 meters wide, with the landscape carving automatically where the water flows. Add gentle flow velocity."

What to expect: Claude spawns a Water Body River actor, places spline points along the valley, and enables landscape sculpting so the terrain automatically carves a riverbed. Flow velocity is set for visible current in the water material.

Step 4: Set up the sky and weather

/skill weather-system

Tell Claude:

"Set up a late afternoon sky with the sun at about 25 degrees above the horizon. Add volumetric clouds with moderate coverage. Include exponential height fog for atmospheric haze in the valley."

What to expect: Claude configures the Sky Atmosphere, sets the directional light angle for late afternoon warmth, adds volumetric clouds with realistic layering, and places height fog concentrated in the lower valley area. The scene now has atmospheric depth.

Step 5: Scatter objects with PCG

/skill pcg-basics

Tell Claude:

"Create a PCG graph that scatters rocks and fallen logs across the landscape. Rocks should cluster near the river banks and on steep slopes. Logs should appear randomly in forested areas. Use density filtering so objects do not overlap foliage."

What to expect: Claude creates a PCG graph with surface sampling, slope-based filtering, and density controls. Rocks concentrate near water and on rocky slopes while logs scatter among trees. The graph runs procedurally. Change the seed and you get a different but equally natural distribution.

Step 6: Enable world streaming

/skill level-streaming

Tell Claude:

"Enable World Partition for this level. Set grid size to 128m cells. Configure HLOD for distant terrain and foliage. Make sure the streaming setup handles the PCG-generated objects."

What to expect: Claude enables World Partition, divides the world into grid cells, and configures Hierarchical LOD so distant areas render simplified geometry. PCG objects and foliage are assigned to streaming cells for memory-efficient loading.

Tips & Best Practices

• Start big, refine small. Get the terrain silhouette right before adding details. The overall shape of hills and valleys matters more than surface texture.
• Let the landscape drive placement. Use slope, altitude, and proximity rules for foliage and rock placement rather than hand-painting everything. It is faster and more consistent.
• Water carves terrain, not the other way around. Place rivers after terrain and let the Water System carve the landscape. Fighting this order creates artifacts.
• Height fog sells scale. A little atmospheric fog in valleys makes distant terrain feel real. Without it, large landscapes look flat and artificial.
• Test streaming early. Enable World Partition before your level gets too complex. Retrofitting streaming into a finished level is painful.

Next Steps