Games that dig and build
Players raise, lower, smooth and flatten the ground, and undo it stroke by stroke.
Brass Orrery · plugins for Unreal Engine
Unreal Engine plugins for worlds that change while the game runs
Each plugin ships with its C++ source, a guide that matches the code, and a page that lists what it does not do. The first is Orrery Terrain, for Unreal Engine 5.8.
Who it is for
What you can build with it
Four ways studios use a ground that changes while the game runs. Each links to the part of the guide that shows it.
City builders and colony sims
Level a site for each building with a plate, and keep the changed ground in the player's save.
Transport and infrastructure
Cut and fill roads, rail beds and canal banks along a spline, with the cut and fill volumes before you commit.
Real-world terrain from elevation data
Import GeoTIFF elevation models and heightmaps once in the editor. The Alpine_Hero sample is 64 by 64 km of Switzerland.
Version 1.0 has no caves or overhangs, because the ground is a heightfield, and no Nanite terrain. What 1.0 does not do
Products
One plugin today, more of the Orrery family later
Each Orrery plugin is its own Fab product and works on its own. They are designed to work together.
Orrery Terrain
Version 1.0, coming to FabA heightfield terrain you sculpt, paint and build on while the game runs. Every edit can be undone and saved, and a listen server replicates it to everyone who joins.
Orrery Rail
Coming laterTrack, junctions and trains, built on the same ground model as the terrain. No release date yet.
Later Orrery plugins
Road and other transport modes are planned. Each gets its own page, guide and limits page when it is ready to be used.
Published openly
Checkable before you buy
- A figure comes with its conditions
- The machine, the build and the date, or it is not on the site. For example, a 64 km world with edits loads and verifies in 1.54 s on an i7-12700H laptop with an RTX 3060 Laptop GPU (2026-10-21).
- Every product has a limits page
- It is linked from the product page, the guide and the Fab listing. Orrery Terrain's limits.
- The source is included
- Fab code plugins ship with their C++ source. You can read it, step through it and patch it.
- Bugs get a reply time
- Every report gets a first reply from a person within two business days. Orrery Terrain's support.
The studio
A one-person studio in Belgium
Brass Orrery is an independent studio of one developer in Belgium. The publisher's details are in the legal notice.