Populators

How to create, adjust, and customize populators in Build mode – the procedural environment generators that turn one prompt into a hundred placed assets.

Populators are procedural containers that distribute assets across an area. The conceptual page is Populators; this page is the build-side how-to. Create one, adjust its asset mix, change density, regenerate, convert specific instances into editable objects.

Asset library "Add an Object" panel open with the Populators category active, showing the Empty Populator template plus Generate 3D and Import Asset action buttons on the right

Watch

Active populator in Build mode with its cyan-blue trapezoidal footprint outline visible. The populator is filled with golden flowers and the contextual menu is hovering above it for adjustments

What it does

The asset library has individual assets and the AI Composer outputs populators. The Build-mode populators page is for everything you do to a populator after one exists in your scene: tune its mix, scale its footprint, swap layout style, override how it interacts with other geometry.

How to create one

Two pathways, in increasing manual control:

1. AI Composer prompt. Type "create a tropical forest" or "build a city block" in the AI Composer panel. The agent creates a populator with the asset mix and layout that match the prompt. Fastest path; results need refinement.

2. Library populator templates. The asset library has a category for ready-made populators – crowds, traffic, vegetation density variants. Drag one in and adjust.

How to adjust one

Click the populator's footprint to select. The contextual menu opens a populator panel with the controls below.

Shape

The populator's footprint shape. Change the shape and the footprint's edit handles change with it. Resizing or reshaping regenerates instances; the populator picks new positions, and existing instances within the new bounds are preserved where possible.

Size

Scales the populator's footprint as a whole.

Density

Controls how many instances are placed within the footprint. Increase for thicker forests and busier crowds; decrease for sparser layouts.

Falloff

Controls how density tapers toward the footprint's edges. A hard falloff produces a crisp boundary; a soft falloff blends the populator into its surroundings.

Rotation

Sets the rotation behavior for placed instances. Use to align placements with the footprint's orientation or to randomize per instance.

Scale

Sets the size behavior for placed instances. Use to introduce variation across the placed assets.

Asset types

Every asset type the populator distributes shows in the asset-types section. Drag a new asset from the asset library directly onto the populator panel to add it. Each entry can be removed or weighted within the populator's mix.

Common mistakes

Don't try to lock instances inside a populator. The lock will be silently overridden the next time the populator regenerates (which happens on density changes, layout switches, footprint resizes). For anything you need to lock, place a regular asset instead.

• Tweaking density before tweaking the asset mix. Density is a multiplier; the mix is the substance. Get the asset list right first, then adjust density.

• Stacking populators without culling. Two overlapping populators (a forest and a flower bed) will cross-spawn. Use the culling controls on each so they don't fight each other.

Related

• Populators (concept)

• AI Composer

• Asset library

• Scene Outliner