Biome Generator
The Biome Generator is a Pro-only extension that produces full procedural environments from a single sentence. It plans biome layers, picks meshes from your project by name, writes a compilable PCG graph, and drops a drawable spline blueprint into the level.
Enable the extension
In a chat, click the + in the input bar and toggle Biome Generator. The toggle is per-chat, so you can have one chat using it and another not.
Your first biome
Type something like:
Dense pine forest with scattered rocks, thick ground cover, along a spline.
The agent will:
- Plan the biome (layers: canopy, understory, ground, accents).
- Scan your Content Browser for matching Static Meshes.
- Generate a PCG graph under
/Game/NwiroAssets/{ProjectName}/. - Create or reuse a spline blueprint
BP_{ProjectName}. - Show a PCG Graph Ready card with a Place in Scene button.
Click Place in Scene and the blueprint drops into your active viewport. Drag the spline points to reshape the area.
Iteration
Stay in the same chat and ask for modifications:
Make it denser.
Swap the pines for oaks.
Remove the rocks near the spline center.
The agent runs a delta update: it rewrites only the changed parts of the graph and re-uses the same spline blueprint. No re-spawn, no cleanup.
Constraint keywords
The generator understands spatial relationships in plain English:
| Keyword | Effect |
|---|---|
around <X> | Place elements encircling the reference |
near <X> | Place close to reference |
avoid <X> | Keep clear of reference |
clustered | Group in patches |
scattered | Spread evenly / randomly |
along the spline | Follow the spline you’ll edit afterwards |
Example:
Dense pine forest along the spline. Clustered bushes near the trees. Scatter mushrooms around the fallen logs. Avoid the center clearing.
Biome keywords
Use at least one biome word so the generator knows which mesh family to draw from.
| Biome | Prompt hints |
|---|---|
| Alpine | ”pine forest”, “mossy alpine”, “snowy slope” |
| Tropical | ”tropical island”, “palm grove”, “jungle floor” |
| Forest | ”autumn forest”, “birch grove”, “deciduous floor” |
| Grassland | ”lush meadow”, “wildflower field”, “oak savanna” |
| Desert | ”arid canyon”, “cacti plain”, “rocky desert” |
| Medieval | ”overgrown courtyard”, “abandoned garden”, “creeping ivy” |
Output locations
- PCG Graph lands at
/Game/NwiroAssets/{ProjectName}/PCG_{ProjectName}_vN.uasset. Each iteration bumps the version, so you can roll back. - Spline blueprint lands at
/Game/NwiroAssets/{ProjectName}/BP_{ProjectName}.uasset. Same blueprint across iterations; the generator just re-binds the newest graph. - Chat card: every generation shows up as a PCG card in the chat, with a Place in Scene button you can re-click later to respawn the same environment.
Naming matters
The generator matches prompt keywords to meshes by name. Generic names like Mesh_001 can’t be matched. See Asset Naming for the conventions that work.
No meshes? Use the demo pack
If your project is a fresh template with no foliage assets, click Download Demo Assets in the chat header. The Stylescape HD pack covers 6 biomes with 224 meshes and is ready for the Biome Generator immediately.
Limitations
- Pro-only. The Biome Generator pipeline runs on Nwiro’s backend; the Integration Kit doesn’t include it.
- Static Meshes only. The generator places Static Meshes along the spline. Skeletal meshes, blueprint actors with dynamic logic, etc. aren’t targeted by the pipeline yet.
- Asset library quality dominates output quality. With 3 tree meshes the forest will have 3 trees. Variety matters; aim for 4-8 meshes per layer.
- Large dense biomes can impact editor performance. If you see FPS drops, reduce density with “make it sparser” or split the biome across multiple shorter splines.
Next steps
- Asset Naming: make sure your meshes are pickable by the generator.
- Prompt Engineering: get reliably good results across different biomes.
- Demo Assets: one-click install the Stylescape HD pack.